Influenza is a highly contagious respiratory tract disease and is considered a serious community health problem. Influenza viruses possess multiple conserved epitopes which are used for designing ...universal vaccines. To this aim, the gene coding for N-terminal part of M2e (SLLTEVET) and HA2 (GLFGAIAGF), was synthesized, linked by a (Gly4Ser)4 peptide linker, and cloned into pGS-21a vector. Afterwards, the construct was transferred into E. coli BL21 (DE3) cells to produce the designed antigenic protein called M2e-HA2. Immunization of mice with these peptides significantly induced humoral immune responses against the influenza virus. Three weeks after the last booster, mice were inoculated intranasally with 1 × 106 EID50 of H9N2 virus. The results indicated that the recombinant M2e-HA2 fusion protein could protect mice against H9N2 virus.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Intra-intestinal pathogenic and antibiotic resistant strains of Escherichia coli are responsible for mild to severe gastrointestinal lesions mediated by various virulence and resistance factors. This ...study was undertaken to determine the genes related to the extended-spectrum β-lactamase producing and hybrid pathotypes of E. coli isolates from diarrheic human cases in southeast of Iran.
Totally, 467 gastrointestinal patients were considered to collect 467 fecal samples during four years (2016 to 2020). Four pathotypes of E. coli (EPEC, ETEC, EHEC, STEC) were screened for five virulence genes, including eae, stx1, stx2, st, and lt using the conventional PCR method. The detected E. coli pathotypes were subjected to determine phenotypic and genotypic β-lactam resistance properties using disc diffusion method and the conventional PCR, respectively.
The virulence profiling of E. coli isolates showed that from 467 (12.63%) isolates, 59 belonged to the four pathotypes of STEC (30/59; 50.8%), EPEC (11/59; 18.6%), ETEC (8/59; 13.5%), EHEC (5/59; 8.4%) and also three hybrid pathotypes of STEC/ETEC (3/59; 5%), EHEC/ETEC (1/59; 1.6%), and EPEC/ETEC (1/59; 1.6%). The phenotypic antibiotic susceptibility testing showed that from 59 isolates, 23 (38.9%) were identified as the ESBL-producing and 58/59 (98.3%) isolates were positive for at least one of the studied β-lactam genes.
This study showed considerable occurrence of the β-lactam resistant diarrheagenic E. coli strains in southeast of Iran. Presence of the hybrid pathotypes detected in this research might potentially lead to more severe intestinal infections. Therefore, there is a need to increase surveillance to reduce the spread of antibiotic-resistant E. coli pathotypes in this region.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Determination of snow characteristics in mountainous basins is difficult due to the complex spatial and temporal variability of snow cover. Accurate representation of snow cover variations in space ...and time is an important factor in snowmelt modeling, hydrological forecasts, water resources planning, and drought management. This study demonstrates how remotely sensed data can complement the measurements of ground hydro-meteorological data to simulate the spatial and temporal variations of snow cover characteristics in a mountainous basin. In this paper, we studied Karun basin, located in the south west of Iran, because of its importance in accumulating large snow reserves, and subsequently contributing snowmelt to the total runoff. Snow cover variability was simulated by extraction of maps of snow cover indices using remotely sensed data. Contribution of snowmelt to the runoff was determined using a seasonal water balance model as well as estimations based on indirect approaches by modeling variables such as critical temperature, which is an important variable in snow studies. Agreement between indirect approaches used in this paper is an encouraging result that shows the reliability of the procedure where snow data is scarce. The results of correlation analysis between topographic and meteorological variables with snow cover indices suggested that elevation is the single most important variable on large-scale snow variability.
To evaluate efficacy concepts of Poulvac
®
E
.
coli
live vaccine, five groups of day-old broilers were provided. Two groups were vaccinated, but challenged by different bacteria, one by
E
.
coli
O78 ...and the other with an untypable acute field
E
.
coli
isolate; the other two groups acted as positive control, not vaccinated, but challenged with the
E
.
coli
O78 and an untypable acute field isolate. The last group served as environmental control (not vaccinated, not challenged). The challenge was done intratracheally at day 28 and birds were necropsied and examined 1 week later to evaluate vaccine protection. A field trial was performed in 23,000-broiler farm containing two separate partitions with the same condition; one partition received the vaccine at 1-day age, but the other remained unvaccinated; both groups observed daily for 47 days to evaluate vaccine affection on growth, weight, and behavior. No unfavorable reaction, abnormal behavior, death, or gross lesion observed following administration of Poulvac
®
E
.
coli
, Zoetis vaccine in vaccinated birds neither in efficacy survey, nor in field trial. Weighing data analysis before challenge implied that, in spite of a greater weighing number in vaccinated birds, there was no any significant difference between vaccinated and unvaccinated birds (
P
> 0.05). Following the challenge, vaccinated birds demonstrated milder signs; also, healthy carcasses increased in vaccinated birds (
P
= 0.000), which revealed that the vaccine can protect against both
E
.
coli
O78 and an acute field
E
.
coli
isolate. Altogether, factors which vaccine could cause significant difference were as follows: point prevalence, airsacculitis, pneumonia, peritonitis, final weight after challenge, and feed conversion ratio.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Shiga toxin-producing
Escherichia coli
(STEC) strains are responsible for outbreaks of human intestinal diseases worldwide. Pigeons are distributed in public areas and are potential reservoirs for ...pathogenic bacteria. One hundred fifty-four fresh fecal samples were obtained from trapped pigeons in southeast of Iran and were cultured for isolation of
E. coli
. The isolates were examined to determine the prevalence of
stx1, stx2
, and
eae
genes, antimicrobial resistance, and their phylotypes. The confirmed
E. coli
isolates (138) belong to four phylogenetic groups: A (54.34%), B1 (34.05%), B2 (3.62%), and D (7.79%). Thirteen (9.42%) isolates were positive for one of the examined genes. Eight isolates (5.79%) were positive for
eae
, four (2.89%) for
stx2
, and one isolate (1.44%) for
stx1
gene. Phylotyping assays showed that eight
eae
-positive isolates fall into three phylogroups; A (three isolates), B1 (three isolates), and D (two isolates), whereas four
stx2
-positive isolates belonged to the A (three isolates) and D (one isolate) groups. The
stx1
-positive isolate belonged to phylogroup A. One hundred six isolates (76.81%) showed resistance to at least one of the selected antibacterial agents. The maximum resistance rate was against oxytetracycline (73.91%), and the minimum was against flumequine (2.17%). Twenty different patterns of drug resistance were observed. According to the results, pigeons could be considered as carriers of STEC strains. However,
E. coli
isolates of pigeon feces increase the potential of these birds to act as a reservoir of multiple antibiotic resistant bacteria.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background: Escherichia coli (E. coli) is a major cause of urinary tract infection in children and women. Several virulence factors have been detected in uropathogenic Escherichia coli strains. P, S ...and Afa fimbria are the most important factors which are coding by pap, sfa and afa genes, respectively. This study aimed to determine the presence and prevalence of fimbrial virulence genes in Escherichia coli isolates from patients with urinary tract infection in Rafsanjan city, Iran. Methods: In this study, 145 urine samples were cultured for identification of Escherichia coli. The isolates were examined via standard biochemical tests. DNA extracts from the confirmed isolates were examined to determine papEF, afaBC and sfa / focDE genes using multiplex-polymerase chain reaction (PCR) method. Findings: Among the cultured samples, 122 Escherichia coli isolates were determined. Virulence genes genotyping of isolates showed that 38.50% of the isolates were possessed at least one of the three virulence genes. The papEF gene was the most prevalent (18.85%) and prevalences of sfa/focDE and afaBC were 2.45% and 0.81%, respectively. Twenty isolates (16.39%) contained both papEF and sfa/focDE genes. Conclusion: The results of this study in comparison with other researchers showed that papEF gene is in the high frequency, and then, afaBC and sfa/focDE fimbrial genes.
Karstic watersheds are one of the most important areas for water supply. Because the role of groundwater contribution to surface water flow in karst watersheds is not well understood, the commonly ...used hydrologic models in most regular basins do not provide satisfactory estimates of runoff in karstic regions. This paper uses time-series analysis to model karstic flow in the Sangsoorakh karst drainage basin in the Karkheh subbasin of southwest Iran. The comparison of model forecasting performance was conducted based upon graphical and numerical criteria. The results indicate that autoregressive integrated moving average (ARIMA) models perform better than deseasonalized autoregressive moving average (DARMA) models for weekly, monthly and bimonthly flow forecasting applications in the study area.
Three hundred fifteen bacteriological samples were obtained from feces and both external and visceral cavity surfaces of carcasses of 105 healthy buffalo slaughtered in southwest of Iran. Confirmed
...Escherichia coli
isolates were examined for antimicrobial resistance phenotypically and were screened for
stx
1
,
stx
2
, and
eae
genes and their subtypes and assessment of antimicrobial resistance genes by regular PCR and RFLP techniques. One hundred forty-five
E. coli
were isolated from feces (96 isolates) and external (37) and internal (12) surfaces of carcasses. Results showed that the prevalence of STEC, EPEC, and EHEC pathotypes was 2.8%, 0.7%, and 0.7% respectively. Among 6 (4.13%) positive isolates for examined genes, 4 (2.8%) isolates were positive for
stx1
, 3 (2.1%) for
stx2
, and 2 (1.4%) for
eae
gene. The detected genes were classified into
stx
1
a
(4 isolates),
stx
2
a
,
stx
2
b
,
stx
2
c
,
eae
-β, and unknown subtypes. The most prevalent antibiotic resistance gene was
sulII
(11.03%). The
tetB
,
qnrB
,
floR
,
bla
TEM
,
bla
SHV
, and
aad
A
genes were found to a lesser extent, and all isolates were negative for
bla
CTX-15
,
bla
OXA
,
aac(3)-I
,
tetA
,
cat1
,
qnrA
,
sulI
,
dhfrI
, and
dhfrV
genes. Twelve combination patterns of antibiotic-resistant genes were observed. Maximum phenotypically resistance rate was against doxycycline (91.83%), and the minimum was against ceftazidime and florfenicol (2.75%).
E. coli
isolates from feces and carcasses of slaughtered buffalo can be considered a mild reservoir for
stx
and
eae
genes. However, healthy buffaloes could be considered a potential reservoir of multiple antibiotic resistance genes in
E. coli
isolates
.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To determine the phylogenetic groups and prevalence of diarrheagenic Escherichia coli (E. coli) (DEC) genes from children less than five years of age with diarrhea in southeast of Iran.
A total of ...142 E. coli isolates were isolated from diarrheic samples. The isolates were examined for detection of virulence determinants and their phylogenetic background by PCR technique.
The E. coli isolates fall into four phylogenetic groups: A (40.14%), B1 (18.31%), B2 (16.90%) and D (24.65%). Eighty isolates were positive for at least one of the examined DEC genes. E. coli isolates were classified in enterotoxigenic E. coli (52 isolates), enteroaggregative E. coli (23), atypical enteropathogenic E. coli (9), enteroinvasive E. coli (2).
This study demonstrated the importance of enterotoxigenic E. coli and enteroaggregative E. coli pathotypes in the childhood diarrhea. An epidemiologic surveillance especially for DEC, would be useful in control and prevention of infectious diarrhea in children.
Eighty-four
Escherichia coli
isolates from canine pyometra were examined to detect the antibiotic resistance profiles, phylogroup/subgroups and virulence genes. Twenty-seven (32.14%) ...antibiotic-resistant isolates were recovered, which were classified into 19 different antibiotic resistance patterns. The maximum resistance was against sulfadiazine and tetracycline. The antibiotic resistant isolates mostly belonged to A (40.74%) and D (29.62%) phylogroups. Among other examined isolates, 19.04% belonged to B1 phylogroup and remaining fell into six phylogenetic subgroups: A
0
(25.00%), A
1
(16.66%), B2
2
(10.77%), B2
3
(5.95%), D
1
(14.28%), and D
2
(8.33%). All isolates possessed at least one virulence gene and
fimH
was the most common gene. Frequency of other virulence genes were estimated as
sfa/focD-E
(58.33%),
papE-F
(44.04%)
, hlyA
(34.52%),
cnf1
(28.57%),
iutA
(17.85%), and
afaIB-C
and
cdt
genes (2.38%). Sixteen combinations of virulence genes were detected, with the combination
cnf1, fimH, hlyA, papE-F, sfa/focD-E
being the most prevalent pattern. None of the isolates contained the
cnf2
and
ipaH
genes.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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