1,177 research outputs found
Pseudomonas cichorii as the causal agent of midrib rot, an emerging disease of greenhouse-grown butterhead lettuce in Flanders
Experimental modulation of capsule size in Cryptococcus neoformans
Experimental modulation of capsule size is an important technique for the study of the virulence of the encapsulated pathogen Cryptococcus neoformans. In this paper, we summarize the techniques available for experimental modulation of capsule size in this yeast and describe improved methods to induce capsule size changes. The response of the yeast to the various stimuli is highly dependent on the cryptococcal strain. A high CO(2) atmosphere and a low iron concentration have been used classically to increase capsule size. Unfortunately, these stimuli are not reliable for inducing capsular enlargement in all strains. Recently we have identified new and simpler conditions for inducing capsule enlargement that consistently elicited this effect. Specifically, we noted that mammalian serum or diluted Sabouraud broth in MOPS buffer pH 7.3 efficiently induced capsule growth. Media that slowed the growth rate of the yeast correlated with an increase in capsule size. Finally, we summarize the most commonly used media that induce capsule growth in C. neoformans
A survey of bacteria and fungi associated with suspected cases of meningitis among children attending some selected hospitals in Kano
Bacterial meningitis is one of the most potentially serious infections occurring in the Children age group, with a high incidence of acute complications and risk of long-term morbidity and mortality. The aim of the research was to Survey the Bacteria and Fungi Associated with Suspected Cases of Meningitis among Children Attending Some Selected Hospitals in Kano State, hundred samples of cerebrospinal fluids (CSF) were collected through lumbar Children aged 0-12years suspected of having Meningitis. The samples were Nigeria. Three puncture from subjected to macroscopic examination, microscopic examination, culture tests. Bacterial and fungal isolates were confirmed by biochemical tests and serology. The isolates were subjected to antimicrobial sensitivity tests using standard techniques. The results obtained were analysed and a prevalence of 8.0% was obtained for bacteria while that of fungi was 0.33%. Analysis of the result according to age group showed that Children in the age group 0-2years had the highest percentage of Meningitis (7.7%:23/300) while those in the age group 3-4 years (0.3%:1/300) and 11-12 years had the lowest (0.3%:1/300). However there were no significant differences between the age group and the prevalence of Meningitis (0.1042). Analysis of the result according to occurrence of isolated organism showed that gram negative Bacteria Heamophilus influenzae type b had the highest frequency of occurrence (48:12/25) while the least were Neisseria meningitidis C/W135 (4%:1/25), Salmonella paratyphi C (4%:1/25), Streptococcus species (Viridans group) (4%:1/25), Candida famata (4%:1/25). Analysis of the result in relation to the study sites showed that the highest number of positive cases were obtained from Muhammad Specialist Hospital (MMSH) (52%:13/25) while the lowest from Aminu Kano Teaching Hospiatal (AKTH) (4%:1/25). However there was a significant difference between the study sites and the number of positive cases (0.004). Antibiogram of the bacterial isolates showed that ceftriaxone (91.7%:11/12) and ciprofloxacin (91.7%:11/12) were found to be most sensitive to Haemophilus influenzae type b and least sensitive to trimethoprim sulfamethoxazole (8.3%:1/12). The yeast, Candida famata was found to be (100%:1/1) sensitive to ketaconazole, fluconazole, itraconazole and amphotericin B. It can be concluded that the overall prevalence of Bacteria in the study sites was 8.0% while that of fungi was 0.33%. Gram negative bacteria Haemophilus influenzae type b were found to be the major cause of meningitis in the study sites which are most sensitive to cefriaxone (91.7%:11/12) and ciprofloxacin (91.7%:11/12) and least sensitive to trimethoprim-sulfamethoxazole (8.3%:1/12).Keywords: Cerebrospinal fluid, Hospitals, isolates, meningitis, occurrence, paediatrics, sensitivity
SCREENING BAKTERI PROTEOLITIK TERMOFILIK DARI SUMBER AIR PANAS SINGGAHAN TUBAN SCREENING PROTEOLYTIC THERMOPHILIC BACTERIA FROM HOT SPRINGS SINGGAHAN TUBAN
Abstrak. Penelitian ini bertujuan untuk melakukan screening bakteri proteolitik termofilik dari sumber air panas Singgahan Tuban. Isolasi dilakukan menggunakan media Luria Bertany dan screening dilakukan menggunakan media agar skim milk 6%. Indeks Proteolitik (IP) bakteri ditentukan dengan membandingkan diameter zona bening dan diameter zona pertumbuhan koloni. IP yang relatif besar dipilih untuk diproduksi dan ditentukan aktivitas proteolitiknya menggunakan media yang mengandung kasein 2%. Pengukuran aktivitas enzim protease menggunakan reagen Follin Ciocalteu, yang diukur dengan spektrofotometer UV-Vis pada panjang gelombang 750 nm. Hasil screening menunjukkan bahwa dari 76 isolat bakteri yang diperoleh, 28 isolat diantaranya mampu menghasilkan protease. Isolat dengan kode ST-57 memiliki IP dan aktivitas terbesar yaitu 7,0, dan 0,2489 Unit/mL.
Kata kunci: Bakteri proteolitik termofilik, indeks proteolitik, aktivitas enzim protease
Abstract. This research aimed to screening proteolytic thermophilic bacteria from hot springs Singgahan Tuban. Isolation was done Luria Bertany medium and screening was done by using 6% skim milk agar medium. Proteolytic index (IP) bacteria determined by comparing the diameter of clear zone and colony growth diameter of the growth zone. The big IP was choosen for being produce and to determine the proteolytic activity using casein 2 % as a medium. Enzymes from proteolytic bacteria isolate then produced and measured it proteolytic activity used medium containing 2% casein. Enzyme activity test used Follin Ciocalteu reagent, measured with UV-Vis spectrophotometer at 750 nm. Screening yield from 76 isolates, 28 isolates able to produce proteases. Isolates with code ST-57 had an IP and the greatest activity 7.0, and 0.2489 Units/mL.
Keywords: Proteolytic thermophilic bacteria, proteolytic index, protease enzyme activit
Rapid molecular detection of salmonella from produce using real-time PCR
Recent outbreaks of Salmonella linked to fresh produce emphasize the need for rapid and sensitive assays to help control outbreaks. Reverse-transcriptase PCR (RT-PCR) detects the presence of mRNA (shorter half-life than DNA), with greater potential of detecting viable cells. Rapid real-time methods using fluorescent dyes and probes simultaneously detect and confirm the presence of target nucleic acid, eliminating the need for gel electrophoresis. The objective of this research was to rapidly detect Salmonella Typhimurium from spiked lettuce, tomatoes, and peppers using real-time RT-PCR. Washed and ultraviolet light treated lettuce (~25gram), tomato (~100g), and peppers (~130g) samples were inoculated with high (10âž to 10ⶠCFU) and low (10Âł to 10ÂčCFU) Salmonella Typhimurium overnight cultures. Samples were then rinsed or hand massaged with 225 ml 0.05 M glycine-saline buffer containing 0.05% Tween and 3% beef extract.Un-inoculated washed produce and sterile buffer were used as negative controls; with S. Typhimurium as a positive control. RNA was extracted from each sample using the Qiagen RNeasy Mini Kit. RT-PCR was carried out using a SYBR Green I RT-PCR kit with previously described Salmonella specific invA gene primers and an internal amplification control (IAC) to eliminate false negatives. Reaction conditions were RT at 50 degree Celsius/40min; PCR at 95 degree Celsius /45s, 58 degree Celsius /45s, 72 degree Celsius /45s for 40 cycles followed by melt temperature(Tm) analysis in a BioRad iCycler to determine specific invA product (~Tm=87.5 degree Celsius) and IAC (Tm=82 degree Celsius). To improve detection sensitivity of low inocula, spiked lettuce, tomatoes, and peppers were pre-enriched in buffered peptone water for 6 hours at 37 degree Celsius, followed by RNA extraction and RT-PCR detection. Each experiment was repeated twice.Real-time RT-PCR after 6-h pre-enrichment, Qiagen RNA extraction and the SYBR Green I kit gave Salmonella detection up to 10Âł CFU/25g from lettuce, 10⎠CFU/~130g from tomatoes, and 10⎠CFU/25g from peppers. Without enrichment, detection limits were 10ⶠCFU/25g for lettuce, 10â· CFU/25g for tomatoes, and 10â· CFU/25g for peppers. Sensitive and rapid detection of Salmonella from spiked lettuce, tomatoes, and peppers could still be obtained within one day (~2 working shifts)
AKTIVITAS BAKTERI PROTEOLITIK YANG DIISOLASI DARI SUMBER AIR PANASSINGGAHAN, TUBANPROTEOLYTIC MICROORGANISMS ACTIVITY ISOLATD FROM HOT SPRINGSINGGAHAN, TUBAN
Abstrak. Penelitian ini bertujuan untuk mendapatkan bakteri penghasil protease termostabil dari sumber airpanas Singgahan, Tuban (Jawa Timur) serta menentukan aktivitas protease isolat. Isolasi bakteri dilakukanmenggunakan media Luria Bertani (LB). Penapisan dilakukan menggunakan media skim milk agar.Pengujian aktivitas proteolitik secara kuantitatif dilakukan dengan metode kolorimetri menggunakan reagenFolin Ciocalteu. Diantara 75 isolat yang diperoleh dari hasil isolasi, 27 isolat bakteri mampu tumbuh padamedia skim milk agar pada suhu inkubasi 53â°C dan memiliki potensi sebagai penghasil protease denganindeks proteolitik (IP) 1.8-9. Isolat dengan nilai indeks proteolitik relatif besar kemudian diuji aktivitasproteolitik secara kuantitatif dengan metode kolorimetri. Aktivitas protease kasar tertinggi dimiliki oleh ST-30 yaitu sebesar 0.2520 U/mL dengan nilai IP 9 serta mampu bertahan sampai suhu 75â°C.Kata-kata kunci: Bakteri termofilik, indeks proteolitik, aktivitas proteolitikAbstract. This research aim to got thermostable bacteria producing protease from hot spring Singgahan,Tuban (Jawa Timur) and determined the protease activity. Isolation was carried out using Luria Bertany(LB) medium while the screening using skim milk agar medium. Proteolytic activity quantitatively done withcolorimetric method using Folin Ciocalteau. Total of 75 strains of thermophilic bacteria were isolated and27 isolate bacteria grew well at skim milk agar medium in high temperature (53â°C) and have potential asprotease producing bacteria with proteolytic index (PI) of 1.8-9. Isolate with high relative proteolytic indextested with colorimetric method. Crude protease ST-30 had the highest activity that was 0.2520 U/mL, PI 9and had ability to endure temperature until 75â°C.Keywords : Thermophile bacteria, proteolytic index, proteolytic activit
Evaluation of Prevalence, Transmission, and Prevention Methods of Salmonellosis from Pet Turtles in Michigan
The sale and distribution of turtles with a carapace smaller than four inches in diameter was banned by federal law in 1975 on the grounds that such animals were frequently associated with human Salmonella infections. However, the popularity of these small turtles as pets has resurfaced, and in many places in Michigan they are being sold illegally. This study was conducted in Michigan to determine the prevalence of Salmonella spp. in the most popular pet turtle species, Trachemys scripta elegans commonly known as red-eared sliders, and to evaluate the compliance of pet stores with laws concerning the sale of these animals. One hundred and fifty pet stores nearest to the center of five large cities in Michigan (30 each for Lansing, Detroit, Flint, Kalamazoo, and Grand Rapids) were contacted by phone. During this study, it was found that 41% (7/17) of the stores that indicated that they sold turtles also sold small turtles. Those seven stores were visited and sanitary conditions, animal housing, client education offered, and requirements for sale were observed. Each of these stores sold the authors a small turtle without asking any questions. One store required the authors to sign a form stating that they were buying the turtle for educational purposes, but did not require any verification. Each of the turtles bought was tested for Salmonella carriage. Six out of seven (86%) purchased turtles were positive for Salmonella spp. Among the positive turtles, the serotypes found were S. Litchfield (2/7), S. Norwich (1/7), and S. Welteverden (1/7), one was confirmed as Salmonella but untypable and another was contaminated upon arrival at NVSL and not serotyped. This study showed that the nationwide ban on the sale of turtles with carapaces smaller than four inches in diameter is not being adequately enforced in Michigan, and that the turtles being sold have a high prevalence of Salmonella carriage
Genetic Variability of AdeRS Two-Component System Associated with Tigecycline Resistance in XDR-Acinetobacter baumannii Isolates
The emergence of tigecycline resistance has increased in the last years. Although tigecycline-resistant Acinetobacter baumannii isolates were described all over the world, few reports regarding the molecular basis of this resistance are available. It has been recognized that the overexpression of AdeABC efflux pump is related to the tigecycline-resistant phenotype. In 37 clinical A. baumannii isolates we first determined the tigecycline-resistant phenotype and then, within a selected group, we analyzed the sequence of the adeRS operon, which is involved in the expression of the AdeABC efflux pump. Nucleotide sequence analysis of adeR and adeS showed the presence of 5 and 16 alleles, respectively. These results expose a high genetic variability in both genes, the adeS gene being more susceptible to genetic variation. The presence of 2 AdeR and 2 AdeS new variants were reported. Two of the new AdeRS variants were present in the intermediate and the resistant tigecycline A. baumannii isolates, suggesting a putative role in the development of the observed phenotype. More studies need to be addressed to determine the role of the genetic variability observed in the adeRS operon.Fil: Montaña, Sabrina Daiana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Vilacoba, Elisabet. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Traglia, German Matias. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Almuzara, Marisa. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos ; ArgentinaFil: Pennini, M.. Stamboulian Laboratorio. Unidad MicrobiologĂa; ArgentinaFil: FernĂĄndez, A.. Universidad Favaloro; Argentina. FundaciĂłn Favaloro; ArgentinaFil: Sucari, A.. Stamboulian Laboratorio. Unidad MicrobiologĂa; ArgentinaFil: Centron, Daniela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; ArgentinaFil: Ramirez, Maria Soledad. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en MicrobiologĂa y ParasitologĂa MĂ©dica; Argentin
THE USE OF \u3cem\u3eLACTOBACILLUS SALIVARIUS\u3c/em\u3e L28 AS A BIOPROTECTIVE CULTURE IN DRY FERMENTED SAUSAGES
A challenge study to validate a 5 log10 CFU/g reduction of non-O157 Shiga-toxin producing Escherichia coli (STEC) in dry fermented sausage (DFS) was performed. A 4.49 ± 0.474 log10 CFU/g was achieved over two trials. The results indicated that the process was not effective in reducing the pathogen to the level required of most pathogens by the USDA.
Lactobacillus salivarius L28 (L28) was screened in vitro for the ability to inhibit STEC utilizing the paper disk diffusion method. This strain is a known bacteriocin producer. The results revealed that L28 would be a good candidate for use as a protective culture as large zones of inhibition were noted against the STEC. No zones of inhibition were noted against the commercial starter culture; therefore, it would not adversely impact the quality of the DFS.
The supplementary L28 strain was added to a commercial starter culture to provide an additional hurdle in the protection against STEC. The sausage trial showed the additional strain did not offer a significant difference in reduction of the pathogen (p \u3e 0.05). Further study will be required before L28 could be considered for use as a bioprotective culture
FACTORS RELATED TO ORAL CANDIDIASIS IN ELDERLY USERS AND NON-USERS OF REMOVABLE DENTAL PROSTHESES
This study examined the association between oral candidiasis in elderly users and nonusers of prosthesis and its predisposing factors. To this end, we performed a cross-sectional study where saliva samples from 48 patients were collected they used prosthesis and 43 patients (control group) who did not use. Among the 91 patients, Candida spp were isolated in 40 (83.3%) who used prosthesis and in 23 (53.5%) in the control group. A statistically significant association was determined between the two groups, the isolation of yeasts and dental prosthesis (p < 0.05, OR = 4.3). The most common etiological agent was Candida albicans (37 isolates), with 23 (62.2%) in the denture group and 14 (37.8%) (control group). Among patients who presented clinical manifestations of oral candidiasis (n = 24), 83.3% (n = 20) belonged to the group that wore dentures, while only 16.7% (n = 4) belonged to the control group. Elderly patients with diabetes had 4.4 times higher estimated risk of developing oral candidiasis when compared with individuals without this condition. There was no statistically significant association between being user prostheses and have diabetes with the onset of candidiasis. No statistically significant association was determined between xerostomia, use of prosthesis and oral candidiasis. The use of prosthetics and poor oral hygiene in elderly patients predisposes to the development of oral candidiasis
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