Predictors of protective behaviors among American travelers to the 2009 Hajj.

BACKGROUND: Respiratory-borne infectious diseases can spread rapidly at mass gatherings. The 2009 Hajj took place during the influenza A (H1N1) pandemic. This study investigates factors associated with compliance with recommended influenza A (H1N1)-related health practices and behaviors among American pilgrims to the 2009 Hajj: receiving seasonal influenza vaccinations, receiving influenza A (H1N1) vaccinations, and behaviors intended to mitigate respiratory illness. METHODS: American residents from Minnesota and Michigan completed anonymous surveys prior to and following travel to the 2009 Hajj. Surveys assessed demographics; knowledge, attitudes and practices (KAP) related to influenza A (H1N1); seasonal and H1N1 vaccinations; health-seeking behaviors; sources of health information; and protective behaviors during the Hajj. RESULTS: Pre- and post-travel surveys were completed by 186 participants. Receiving seasonal influenza vaccination was reported by 138 (63%) respondents, and 80 (36%) reported receiving an influenza A (H1N1) vaccine. One hundred forty-four (79%) respondents reported engaging in protective behaviors during the Hajj to prevent illness. In multivariable models, greater perceived severity of influenza A (H1N1) before traveling was associated with: seasonal influenza vaccination (OR=1.74, 95% CI=1.14-2.62, p=.01), influenza A (H1N1) vaccination (OR=2.02, 95% CI=1.35-3.02, p=.001), and engaging in protective behaviors during the Hajj (OR=1.62, 95% CI=1.00-2.63, p=.003). CONCLUSIONS: This study found that accurate knowledge of influenza A (H1N1) symptoms, transmission, and prevention was associated with greater perceived severity of influenza A (H1N1); and perceived influenza A (H1N1) severity was associated with engaging in recommended protective health practices. Understanding the barriers to and facilitators of compliance with recommended behaviors can help guide the development of tailored outreach strategies to mitigate the impact and spread of respiratory disease.

Occurrence of Xanthomonas axonopodis pv. phaseoli, the causal agent of common bacterial blight disease, on seeds of common bean (Phaseolus vulgaris L.) in upper Egypt.

Common bean seed lots collected from different seed dealers and Malawii agriculture station were screened for the presence of Xanthomonas axonopodis pv. phaseoli. In the laboratory the pathogen was isolated following the routine laboratory assay method, i.e. direct plating method using yeast extract-dextrose-calcium carbonate agar medium (YDC). Yellow, convex, mucoid colonies of Xanthomonas were consistently isolated on YDC from seed samples. The presumptive pathogen was confirmed by isolation on semiselective medium, such as mTBM and MD5A. Further, the pathogen was confirmed by biochemical, physiological and, finally, the pathogenicity tests. Five samples out of seven were positive for Xanthomonas. The isolates were found to cause common blight of 3-week-old common bean plants by 7 d after inoculation. Bacteria with the same characteristics as those inoculated were re-isolated from the infected plants.

Thyroglossal Duct Cyst Imaging: Thyroid Scintigraphy Versus Ultrasound

The two imaging modalities most frequently used in thyroglossal duct cyst (TDC) are thyroid scintigraphy and ultrasound. The imaging is mainly used to exclude the cyst from being the only functioning ectopic thyroid tissue. The main objective of this study is to compare the results of scintigraphy and ultrasound. Methods: A total of 56 patients referred to the National Cancer Institute (NCI); University of Gezira in the period from Jan 2007 to Dec 2009 were included in this study; 30 females and 26 males patients; with median of 12.5 years. Data were analyzed by SPSS software. Results: Both thyroid scintigraphy and ultrasound reached the same imaging findings i.e. 53 patients with TDC and 3 patients with ectopic thyroid tissues. The Fisher exact test revealed no significant difference between the two modalities final results (P- value = 1). In addition; Pearson correlation showed complete correlation between the final ultrasound and scintigraphy results (R2 = 1; P-value 0.0001). Furthermore; ultrasound has provided detailed cyst characterization. Conclusion: Both modalities revealed almost identical results. Ultrasound has the additional advantages of being non-ionizing radiation and accurately localizes and characterizes the TDC

Diagnosis of invasive amebiasis by enzyme-linked immunosorbent assay of saliva to detect amebic lectin antigen and anti-lectin immunoglobulin G antibodies.

Saliva from subjects with amebic liver abscess (ALA), acute amebic colitis, asymptomatic infection with Entamoeba histolytica or Entamoeba dispar, and uninfected controls was tested by enzyme-linked immunosorbent assay (ELISA) for the presence of E. histolytica galactose-inhibitable lectin antigen and salivary immunoglobulin (IgG) antibodies to a recombinant cysteine-rich lectin-derived protein (LC3). Salivary lectin antigen was found in 65.8% of subjects with acute colitis, compared to 22.2% of those convalescent from ALA, 10.0% with asymptomatic E. histolytica infection, 9.8% with E. dispar infection, and 2.6% of controls (subjects from the United States and study patients with nonamebic diarrhea) (P < 0.001 for each compared to values for subjects with colitis). Salivary anti-LC3 IgG antibodies were found in 92% of ALA patients regardless of duration of illness and in 83.3% of colitis patients who were symptomatic for at least 7 days (P < 0.001 compared to other study groups). Serum anti-LC3 IgG antibodies were detected in 56.3% of subjects with acute colitis, 100% of subjects with ALA or prolonged colitis, 45% of subjects with asymptomatic E. histolytica infection, 32.3% of subjects with E. dispar infection, and 23.4% of diarrhea controls. In comparison to ELISA for serum anti-LC3 IgG antibodies, the salivary lectin antigen assay is a more sensitive and specific test for acute amebic colitis. Detection of salivary anti-LC3 IgG antibodies by ELISA is an effective means for the diagnosis of ALA and prolonged cases of amebic colitis.

Physiological aspects of fungi isolated from root nodules of faba bean (Vicia faba L.).

The present study was made to isolate and assess some physiological characteristics of root nodule-colonizing fungi. During this study, 17 fungal species were isolated from root nodule samples taken from faba bean plants (Vicia faba L.) collected from different sites at Assiut area (Egypt). The growth of faba bean plants in pots was significantly promoted by soil inoculation with most fungi. Growth was checked in pots with inocula of Cladosporium cladosporioides, Fusarium moniliforme, F: oxysporium, F solani, Macrophominia phaseolina and Rhizoctonia solani which were added separately. All growth-promoting fungi were capable of producing cellulase, pectin lyase, polygalacturonase, protease, urease, amidase, acid phosphatase, alkaline phosphatase and arylsulfatase in growth medium supplemented with the corresponding substrates. Four fungal species, Aspergillus awamori, A. flavus, Penicillium chrysogenum and Trichoderma koningii showed the highest rates of enzyme formation. The effect of the addition of six trace elements to the growth media at 30 micromol/ml on enzyme production revealed some dependency on species, enzyme and metal ion. Cd2+, Hg2+ and Zn2+ generally inhibited enzyme activity. Cu(1+), Fe3+ and Al3+ showed a stimulatory effect. Fungicides (afugan and tilt) and herbicides (brominal and fusilade) at 50 ppm generally promoted enzyme activity, but insecticides (kelthane and fenvalerate) caused some inhibition to enzyme activities. Salinization of the growth media with NaCl strongly inhibited the enzymatic activity of all fungi at concentrations between 0.5 and 1.5%.

Comparison of antigen-capture ELISA to stool-culture methods for the detection of asymptomatic Entamoeba species infection in Kafer Daoud, Egypt.

We performed a prospective field study in the village of Kafer Daoud in Menofia, Egypt to compare the fecal culture method with enzyme linked immuno assay (ELISA) for detection of 170 kDa lectin antigen in feces for diagnosis of asymptomatic Entamoeba histolytica and Entamoeba dispar infection. All subjects with E. histolytica or E. dispar infection detected by culture also had positive ELISA for amebic antigen in their feces and an additional 57 Entameoba infections missed by culture were detected by ELISA (P < 0.001 compared to culture). The presence of fecal anti-lectin IgA antibodies and serum anti-LC3 (recombinant cysteine-rich lectin protein) IgG antibodies were positive predictors for E. histolytica infection (P < 0.03). Of interest, infection with Trichomonas hominis but not Blastocystis hominis was positively associated with E. histolytica infection (P < 0.05). In conclusion, ELISA for detection of fecal lectin antigen is a more sensitive method than fecal culture for detecting asymptomatic E. histolytica infection.

Serum IgM antibody response to the galactose-inhibitable adherence lectin of Entameoba histolytica.

An ELISA for detection of serum IgM antibodies to the galactose-inhibitable adherence lectin of Entamoeba histolytica revealed that 2.8% of uninfected controls, 0.0% of controls infected with other parasites, 13.4% of asymptomatic amebic infections, 55% of colitis patients, and 77% of amebic liver abscess patients from Cairo, Egypt and Durban, South Africa had serum anti-lectin IgM antibodies. Of acute amebic colitis patients with symptoms for less than one week, only 6% possessed serum IgG anti-lectin antibodies, yet 45% had serum IgM antibodies to the amebic lectin. This compares with 65% of sera in acute colitis patients positive for lectin antigen as determined by ELISA with anti-lectin monoclonal antibodies. In conclusion, an ELISA for serum anti-lectin IgM antibodies appears to have greater clinical utility in the setting of acute amebic colitis than an ELISA for anti-lectin IgG antibodies, but is no more sensitive than an ELISA for detection of lectin antigen in sera.

Effect ofLupinus seed diffusates onBradyrhizobium sp. growth and nodulation of lupine.

Seeds of three species of lupine (Lupinus termis, L. triticale andL. albus) were tested to determine if the seed contains diffusable substances toxic to bradyrhizobia.L. albus seeds were less toxic to bradyrhizobia, followed byL. triticale. Six strains ofBradyrhizobium were evaluated for their resistance to the toxic substances in lupine seeds. Zones of growth inhibition were determined on yeast-mannitol-agar medium surrounding surface-sterilized seed. The effect of surface sterilization of seeds by different chemical treatments on seed toxicity was assessed. Seeds soaked in water for 1 h before placing on agar surface significantly decreased the inhibition zone. Also, the effect of soaking seeds in water for 4 h before planting and inoculation on nodulation, nitrogen fixation and plant growth were investigated. Addition of seed diffusate to soaked seeds significantly decreased nodulation and plant growth. Autoclaving the seed diffusate had no effect on the toxicity of the seed diffusate. Addition of the absorbent polyvinylpolypyrrolidone (PVPP) to seed diffusates significantly decreased the inhibitory effect of seed diffusate on nodulation and plant growth. Seed diffusate substances were water-soluble, heat-stable and partially bound to PVPP.

A recombinant cysteine-rich section of the Entamoeba histolytica galactose-inhibitable lectin is efficacious as a subunit vaccine in the gerbil model of amebic liver abscess.

The 170-kDa subunit of the galactose-inhibitable adherence lectin of Entamoeba histolytica mediates attachment to colonic mucins and host cells. The DNA fragment encoding the 170-kDa subunit was produced by polymerase chain reaction (PCR) and divided into four sections by restriction endonucleases. The third section (designated LC3, base pairs 2273-3397) encodes a cysteine-rich fusion protein that was recognized by adherence-inhibitory anti-lectin monoclonal antibodies and serum antibodies from 95% of subjects with amebic liver abscess. Immunization of gerbils with purified recombinant LC3-encoded protein (10 micrograms) with Titermax adjuvant elicited a high-titer serum anti-LC3 IgG antibody response and protective immunity against intrahepatic challenge with 0.5 x 10(6) virulent axenic trophozoites (strain HM1:IMSS; 71% vaccine efficacy, P < .01). In summary, a recombinant cysteine-rich portion of the 170-kDa lectin subunit was highly antigenic, immunogenic, and effective as a subunit vaccine in an experimental animal model of amebic liver abscess.

Protection of gerbils from amebic liver abscess by immunization with recombinant Entamoeba histolytica 29-kilodalton antigen.

The goal of our study was to obtain a highly conserved Entamoeba histolytica recombinant antigen for study as a subunit amebiasis vaccine. We screened a Uni-Zap cDNA library of E. histolytica (strain HM1:IMSS) with human immune sera and isolated a dominant 804-bp cDNA clone. A 33-kDa fusion protein expressed from the cDNA clone was determined by monoclonal antibody binding, DNA hybridization, and nucleotide sequence to be the complete E. histolytica 29-kDa antigen. Serum antibodies to the recombinant protein were detected by enzyme-linked immunosorbent assay in 80% of subjects from Egypt and South Africa with amebic liver abscess. Similar results were found with the native 29-kDa protein. Native and recombinant 29-kDa antigens induced proliferation of lymphocytes harvested from patients with amebic liver abscess (P < 0.01 compared with controls). Intraperitoneal immunization of gerbils with the recombinant fusion protein (10 micrograms) with Titermax adjuvant elicited an antigen-specific serum immunoglobulin G antibody response and was partially protective (54%) against intrahepatic challenge with 5 x 10(5) virulent axenic trophozoites (strain HM1:IMSS). In summary, the recombinant form of the E. histolytica 29-kDa antigen demonstrated serologic specificity for amebic liver abscess, exhibited conserved T-cell epitopes, and was effective as a subunit vaccine in an experimental animal model of amebic liver abscess.

Phosphodiesterase and phosphotriesterase in Rhizobium and Bradyrhizobium strains and their roles in the degradation of organophosphorus pesticides.

Of 13 Rhizobium and Bradyrhizobium strains investigated for the production of cellular and extracellular phosphodiesterase and phosphotriesterase, all were found to produce both enzymes. Phosphodiesterase was produced at a much higher level than phosphotriesterase. Rhizobium meliloti TAL 1373 was the most productive. The extracellular enzymes were activated by inclusion in the assay mixture of Ca2+ or Mg2+. The enzymes were inhibited by Zn2+ but not significantly affected by Cu2+, Co2+ and Mn2+. Both hydrolases were inhibited by dithiothreitol but not by thiol-directed inhibitors, suggesting that sulphydryl groups are not directly involved in catalysis. The enzymes have the ability to hydrolyse some organophosphorus compounds, suggesting that Rhizobium and Bradyrhizobium strains play an important role in the degradation of organophosphorus pesticides.

Utilization of some phenolic compounds by Azotobacter chroococcum and their effect on growth and nitrogenase activity.

Azotobacter chroococcum MH1 was grown in a mannitol and nitrogen free medium supplemented with p-hydroxybenzoic acid, resorcinol, catechol or vanillic acid as a sole carbon source. Growth and nitrogenase activity of p-hydroxybenzoic acid were supported by 8, 6 and 4 mM of p-hydroxybenzoic acid, resorcinol and catechol, respectively. The generation time of 1.71 h in p-hydroxybenzoic acid did not differ from a generation time of 1.64 h, when grown in mannitol. The compound p-hydroxybenzoic acid was utilized rapidly. However, the decomposition of other phenolic compounds tested proceeded slowly. These results suggested that phenolic compounds released during biodegradation of plant wastes could be utilized as carbon sources for both growth and nitrogen fixation of Azotobacter chroococcum.

Differentiation of pathogenic Entamoeba histolytica infections from nonpathogenic infections by detection of galactose-inhibitable adherence protein antigen in sera and feces.

We determined whether epitope-specific monoclonal antibodies to the galactose-inhibitable adherence protein (GIAP) of Entamoeba histolytica could be used in an enzyme-linked immunosorbent assay (ELISA) to detect antigen in serum and feces and differentiate between nonpathogenic zymodemes and the potentially invasive pathogenic organisms that require treatment. Overall, 57% of subjects from Cairo, Egypt, with symptomatic intestinal amebiasis and 42% with asymptomatic infection possessed GIAP antigen in their sera, whereas 4% of uninfected controls or subjects with other parasitic infections possessed GIAP antigen in their sera (P < 0.001). In subjects from Durban, South Africa, only 6% of uninfected controls or those with nonpathogenic E. histolytica infection were positive for GIAP in serum, whereas 3 of 4 with asymptomatic pathogenic intestinal infection and 75% with amebic liver abscess were positive for GIAP in serum. Fifteen stool samples from patients with intestinal amebiasis were available for study; all had a positive ELISA result for fecal GIAP antigen. Epitope-specific monoclonal antibodies identified 8 of 15 subjects with fecal antigen from pathogenic strains. Seven of those eight subjects had adherence protein antigen in their sera, whereas none of seven with apparent nonpathogenic E. histolytica infection had adherence protein antigen in their sera. In summary, we were able to detect E. histolytica adherence protein antigen directly in serum and fecal samples by ELISA. The presence of amebic antigen in serum demonstrated 94% specificity for pathogenic E. histolytica infection, and amebic antigen is present during asymptomatic intestinal infection. In conjunction with antibody detection, this method should be very useful in the diagnosis and management of intestinal amebiasis.

Use of an enzyme-linked immunosorbent assay to detect anti-adherence protein antibodies in sera of patients with invasive amebiasis in Cairo, Egypt.

We used enzyme-linked immunosorbent assay (ELISA) to detect IgG antibodies to the Entamoeba histolytica galactose-inhibitable adherence protein in the sera of 50 uninfected controls, 50 cases with asymptomatic cyst passage, 100 patients with amebic colitis, and six patients with amebic liver abscess from Cairo, Egypt, and in 50 healthy controls from the United States. When the mean + 3 SD value above that of the controls from the United States was used as a criterion for a positive ELISA result, 100% of those with invasive amebiasis, 80% of those with asymptomatic infection, and 64% of the Egyptian controls had anti-adherence protein antibodies. However, when the mean + 2 SD value of Egyptian control sera (optical density = 0.094) was used as the criterion for positivity, 33 (89%) of 37 sera from individuals with invasive amebiasis having symptoms for at least one week were antibody positive, in contrast to only 12% of asymptomatic cyst passers (P < 0.01). In a highly endemic area such as Cairo, Egypt, detection of serum anti-adherence protein antibodies by ELISA may have greatest diagnostic use in patients with symptomatic invasive amebiasis of greater than one week duration.

Synthesis of some new 3-(2'-heterocyclicethyl)-2-methyl-3,4- dihydroquinazolin-4-one derivatives as antimicrobial agents.

3-(2'-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one was reacted with acetylacetone, ethyl acetoacetate and diethylmalonate in the presence of sodium ethoxide to afford the alkylation products IV, V and VI. Compounds IV, V and VI were reacted with hydrazine hydrate, phenylhydrazine, hydroxylamine hydrochloride, urea and thiourea to yield 3-(2'-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-on e derivatives VII-XV. The structures of the synthesized compounds were elucidated by elemental analyses and spectroscopic (IR and 1H-NMR) analyses. The prepared compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.

Synthesis and antibacterial activity of certain quinoline and quinazoline derivatives containing sulfide and sulfone moieties.

Some aryl and/or heterocyclic mercaptans were allowed to react with 8-quinolyl chloroacetate (II), 8-quinolinoxyacetyl chloride (IV) and 3-(2'-chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one (X) in dry benzene and/or sodium hydroxide in absolute ethanol to give corresponding 8-quinolyl-alpha-mercaptoacetate (V), 8-quinolinoxythioacetate (VI) and 3-(2'-arylmercaptoethyl)-2-methyl-4-(3H)quinazolin-4-ones or 3-(2'-heterocyclicmercaptoethyl)-2-methyl-4(3H)-quinazolin-4 -ones (XIa-h). The mercaptans V and XI were subjected to oxidation with hydrogen peroxide/acetic acid mixture (1:2) to afford the corresponding sulfones VII and XII. The structures of the synthesized compounds were elucidated by spectroscopic (IR and 1H-NMR) and elemental analyses. Some of these compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.