Clostridium perfringens is the causative agent of a wide variety of diseases in animals and humans. C. perfringens can produce more than 15 toxins. However, individual strains produce a subset of these toxins. Although a small percentage of C. perfringens isolates (mostly belonging to type A) produce C. perfringens enterotoxin...
Clostridium perfringens type A is the causative agent of a variety of histotoxic and enteric diseases. The ability of C. perfringens spores to germinate in vivo might be due to the presence of nutrient germinants in the host tissue and blood. In the current study, we investigated the ability of...
Clostridium difficile is the causative agent of the majority of antibiotic associated diarrheas. C.
difficile spores are recognized as the morphotype of transmission, infection and persistence.
However, there is a lack of knowledge on how C. difficile spores interact with the host’s
epithelial surfaces. In this context, we have characterized...
High hydrostatic pressure (HHP) is the most-widely adopted novel non-thermal technology for the commercial pasteurization of foods. However, HHP-induced inactivation of bacterial spores remains a challenge due their resistance to the treatment limits of currently available industrial HHP units (i.e., ~650 MPa and 50°C). Several reports have demonstrated that high...
Clostridium difficile´s presence has been reported in meat products stored typically at low temperatures. This study evaluated the viability in phosphate buffer saline (PBS) of spores from epidemic C. difficile strain R20291 (4.6 log CFU/ml) and M120 (7.8 log CFU/ml). Viability was assessed during 4 months at -80°C, -20°C, 4°C...
English: Clostridium difficile is an emerging anaerobic, spore forming pathogen, recognized as the etiological agent of ~ 30% of antibiotic associated diarrheas. Clinical symptoms can fluctuate from mild to moderate diarrhea, pseudomembranous colitis and toxic megacolon. The incidence of C. difficile associated infections (CDAI) is ~ 1% of total hospitalized...
Consumer demand for improved-quality and fresh-like food products have led to the development of new non-thermal preservation methods. High pressure processing (HPP) is currently the novel non-thermal technology best established in the food processing industry. However, many potential HPP applications would require long treatment times to ensure an adequate inactivation...
Sporulation is an important strategy for certain bacterial species within the phylum Firmicutes to survive longer periods of time in adverse conditions. All spore-forming bacteria have two phases in their life; the vegetative form, where they can maintain all metabolic activities and replicate to increase numbers, and the spore form,...
Background: Clostridium difficile is the main cause of nosocomial infections including antibiotic associated diarrhea, pseudomembranous colitis and toxic megacolon. During the course of Clostridium difficile infections (CDI), C. difficile undergoes sporulation and releases spores to the colonic environment. The elevated relapse rates of CDI suggest that C. difficile spores has...
The most frequent cause of pseudomembranous colitis is Clostridium difficile (C. difficile) infection. This type of colitis is characterized by an endoscopic pattern of numerous small, yellowish or whitish plaques diffusely distributed, which typically compromises the rectum extending to proximal colon. Occasionally, the pseudomembranes compromise only the transverse or right...
A beta Poisson dose-response model for Vibrio vulnificus food poisoning cases leading to septicemia was used when evaluating the effect of 15°C depuration on the estimated risk of raw oyster consumption. Statistical variability sources included V. vulnificus load at harvest, time and temperature during harvest and transportation to processing plants,...
The increased severity of Clostridium difficile infection is primarily attributed to the appearance of an epidemic strain characterized as PCR ribotype 027. The only report that identified epidemic C. difficile ribotype 027 in an American country outside of North America comes from Costa Rica, raising the possibility that strains 027...
Clostridium difficile is an important nosocomial pathogen that has become a major cause of antibiotic-associated diarrhea.
There is a general consensus that C. difficile spores play an important role in C. difficile pathogenesis, contributing to infection,
persistence, and transmission. Evidence has demonstrated that C. difficile spores have an outermost layer,...
Phaseolus vulgaris, the common bean, is susceptible to many
bacterial, fungal and viral diseases. However, resistance to several
diseases has been identified in related Phaseolus species, P.
coccineus, P. acutifolius and P. lunatus. Thus, interspecific
hybridization could result in transfer of beneficial characteristics.
One of the problems encountered in interspecific...
Chlamydia trachomatis is an obligate intracellular bacterium that causes diseases of the eye and urogenital tract in humans. It is the cause of the sexual transmitted infection (STI) chlamydia, the most prevalent STI worldwide, and the ocular disease trachoma, the leading cause of infectious blindness. To date there is no...
This dissertation investigates the microbial diversity and factors influencing the assembly of microbial communities in kombucha production, using a combination of 1H Nuclear Magnetic Resonance Spectroscopy, 16S and ITS rRNA metabarcoding, and traditional culture-based microbiological methods. It also explores the diversity of kombucha starter cultures through shotgun sequencing and metabarcoding...
1. Foraging and migration often require different energetic and movement strategies. Though not readily apparent, constraints during one phase might influence the foraging strategies observed in another. For marine birds that fly and dive, body size constraints likely present a trade-off between foraging ability and migration as smaller bodies reduce...
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of thick-billed
murres in the Bering Sea
Orben, R. A., Paredes, R., Roby, D. D., Irons, D. B
1. Foraging and migration often require different energetic and movement strategies. Though not readily apparent, constraints during one phase might influence the foraging strategies observed in another. For marine birds that fly and dive, body size constraints likely present a trade-off between foraging ability and migration as smaller bodies reduce...
1. Foraging and migration often require different energetic and movement strategies. Though not readily apparent, constraints during one phase might influence the foraging strategies observed in another. For marine birds that fly and dive, body size constraints likely present a trade-off between foraging ability and migration as smaller bodies reduce...
Fluid-structure interaction (FSI) has been of significant research interest worldwide over the past several decades because of its variety of applications in both offshore and coastal engineering. Researchers analyzing FSI systems rely heavily on experimental tests in model scale in laboratories or large-scale sea trials. However, these tests are often...
Wheat stripe rust (WSR), also called yellow rust of wheat (Tricitum spp.), causal agent Puccinia striiformis f.sp. tritici (Pst), is a foliar disease of major economic importance on wheat, especially grown in temperate locations. WSR causes major losses of wheat yield, estimated at nearly $ 1 billion per year, and...
Clostridium perfringens type A strains are one of the main causative agents of gastrointestinal (GI) diseases in human and can cause both food poisoning (FP) and non-food-borne (NFB) diseases. Several factors contribute to the pathogenesis of C. perfringens type A strains including the wide presence of C. perfringens spores with...
C. perfringens type A isolates are the causative agents of C. perfringens type A food poisoning (FP) and non-food-borne (NFB) human gastrointestinal diseases. In this study, we evaluated the antimicrobial effect of essential oil constituents (cinnamaldehyde, eugenol, allyl isothiocyanate (AITC), and carvacrol) against C. perfringens FP and NFB isolates grown...
Water is an absolute necessity for life as we know it. It provides a useful medium in which chemical reactions take place that allowed for the development of single cellular organisms. When combined with the evolutionary accident that was pho- tosynthesis, water became not only a useful medium chemical reactions,...
The enterotoxin-producing Clostridium perfringens type A isolates are responsible for the third most common foodborne illness in the United States and can also cause non-foodborne human gastrointestinal (GI) diseases such as antibiotic- associated and sporadic diarrheas. Three important factors contribute to the ability of C. perfringens to cause GI diseases,...
C. perfringens is a Gram-positive, spore-forming, anaerobic pathogenic
bacterium capable of causing a wide variety of diseases in both humans and animals.
However, the two most common illnesses in humans are C. perfringens type A food
poisoning (FP) and non-food-borne (NFB) gastrointestinal (GI) illnesses . These two
major diseases are...
AIM: Species that breed sympatrically often occupy different foraging niches to
mitigate competition for prey. When resource availability declines at the end of
the breeding season, some animals migrate to regions with more favourable
environmental conditions. When these life-history traits combine, foraging
habitat preferences may continue to influence migration patterns...
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during their non-breeding migrations
Rachael A. Orben, David B. Irons, Rosana Paredes, Daniel D
AIM: Species that breed sympatrically often occupy different foraging niches to
mitigate competition for prey. When resource availability declines at the end of
the breeding season, some animals migrate to regions with more favourable
environmental conditions. When these life-history traits combine, foraging
habitat preferences may continue to influence migration patterns...
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migrations
Orben, R. A., Irons, D. B., Paredes, R., Roby, D. D., Phillips, R. A., & Shaffer, S.
A. (2015
AIM: Species that breed sympatrically often occupy different foraging niches to mitigate competition for prey. When resource availability declines at the end of the breeding season, some animals migrate to regions with more favourable environmental conditions. When these life-history traits combine, foraging habitat preferences may continue to influence migration patterns...
Clostridium perfringens is a spore-forming pathogenic bacterium that causes a variety of diseases in human and animals. C. perfringens type A isolates produce enterotoxin (CPE) causing food poisoning (FP) and non-food-borne (NFB) gastrointestinal (GI) diseases including antibiotic-associated diarrhea and sporadic diarrhea. C. perfringens type A food poisoning currently ranks as...
Clostridium perfringens is a spore-forming anaerobic organism that is commonly present in fresh meat and poultry. The organism's spores can survive a range of food processing methods. C. perfringens type F isolates are the causative agents of C. perfringens type F food poisoning (FP) and non-food borne (NFB) human gastrointestinal...
C. perfringens is a spore-forming, gram-positive, anaerobic pathogenic bacterium capable of causing a wide variety of diseases in both humans and animals. However, the two most common illnesses in humans are C. perfringens type A food poisoning (FP) and non-food-borne (NFB) gastrointestinal (GI) illnesses. Interestingly, these two major diseases are...
Clostridium perfringens is an anaerobic, gram-positive, rod-shaped, spore-forming bacterium that leads to a broad range of diseases in humans and animals [23, 27, 50]. Among seven C. perfringens types (type A-G), type F is known to be the most common bacteria that is responsible for causing human food-borne disease outbreaks...
As central-place foragers, seabirds from colonies located close to multiple and/or productive marine habitats might experience increased foraging opportunities and enhanced resilience to food shortages. We tested whether this hypothesis might explain divergent trends in 3 populations of black-legged kittiwakes Rissa tridactyla, a surface-feeding piscivore, in the eastern Bering Sea....
Central place foragers, such as breeding seabirds, need to commute between their nests and foraging grounds, thus close proximity of the breeding colony to productive oceanographic features might be beneficial for seabird reproduction. We tested this hypothesis by investigating the at-sea foraging and breeding behavior of thick-billed murres (Uria lomvia)...
Clostridium perfringens is a Gram-positive, anaerobic, spore-forming bacterium that can produce as many as 17 different toxins and are responsible to cause a wide array of gastrointestinal (GI) and histotoxic diseases in humans and animals. As individual strains produce a subset of these toxins, C. perfringens strains can be classified...
We hypothesized that changes in southeastern Bering Sea foraging conditions for black-legged kittiwakes (Rissa tridactyla)
have caused shifts in habitat use with direct implications for population trends. To test this, we compared at-sea
distribution, breeding performance, and nutritional stress of kittiwakes in three years (2008–2010) at two sites in the...
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no use of basin habitats given that this prey is only
obtained in the basin (Paredes et al. 2012
We hypothesized that changes in southeastern Bering Sea foraging conditions for black-legged kittiwakes (Rissa tridactyla)
have caused shifts in habitat use with direct implications for population trends. To test this, we compared at-sea
distribution, breeding performance, and nutritional stress of kittiwakes in three years (2008–2010) at two sites in the...
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-Legged Kittiwakes to Prolonged
Food-Shortages around Colonies on the Bering Sea Shelf
Paredes R, Orben
We hypothesized that changes in southeastern Bering Sea foraging conditions for black-legged kittiwakes (Rissa tridactyla)
have caused shifts in habitat use with direct implications for population trends. To test this, we compared at-sea
distribution, breeding performance, and nutritional stress of kittiwakes in three years (2008–2010) at two sites in the...
Clostridium perfringens is a pathogenic anaerobic bacterium able to produce more than 17 toxins, allowing C. perfringins to cause a wide variety of diseases in humans and animals. Beside toxins production, C. perfringens able to form a highly resistance spores can survive in the environments for years. These spores are...
Clostridium perfringens type A isolates produce the spore-specific enterotoxin, CPE, upon sporulation in the gastrointestinal tract of humans and animals. Spo0A is a response regulator representing the major transcription factor for sporulation initiation in C. perfringens. In Bacillus subtilis, a multicomponent phosphorelay involving five histidine kinases (KinA-KinE), the intermediate response...
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)
Acknowledgments
The Sarker Lab:
Dr. Mahfuzur Sarker
I-hsiu Huang
Dr. Deepa Raju
DanielParedes-Sabja
Nahid
About 48 million cases of Foodborne illnesses (FBIs) are estimated to occur every year in the US. These are diseases caused by contamination of foods with bacteria, viruses, protozoa, parasites and toxic chemicals. Clostridium difficile infections (CDIs) are an important health-care and community associated problem. Since C. difficile spores have...
Clostridium perfringens is the causative agent of gas gangrene and the 3rd most common cause of type A food borne disease in the United States. Critical to the pathogenicity of C. perfringens is the ability of this bacterium to produce highly resistant, metabolically dormant spores that can resume metabolic function...
Vibrio parahaemolyticus is a foodborne pathogen recognized as the leading cause of acute gastroenteritis associated with consumption of raw and undercooked seafood, particularly raw oysters, with major symptoms of nausea, vomiting, abdominal cramps and diarrhea. It is estimated that 45,000 cases of V. parahaemolyticus infection occur each year in the...
Clostridium perfringens type A isolates producing enterotoxin (CPE) are an
important cause of both food poisoning (FP) and non food borne gastrointestinal
diseases (NFBGID) in both humans and animals. C. perfringens type A food
poisoning is caused by isolates carrying the CPE encoding gene (cpe) on the
chromosome while the...
Clostridium perfringens type A isolates, an anaerobic enterotoxigenic spore forming bacterium, are the third leading cause of food-borne disease in the United States. Factors that contribute to the virulence of C. perfringens include the ability of the bacterium to form heat resistant spores and to produce an enterotoxin (CPE). Although...
This thesis synthesizes surficial structural data, a detailed analysis of an earthquake in 1944, and historical seismicity into a new model of crustal scale deformation in the eastern Precordillera in northwestern Argentina in the vicinity of San Juan. The eastern Precordillera was uplifted during previous thin-skinned deformation episodes, and is...
Understanding which factors motivate farmers to adopt certain practices is an important part of helping to solve many agri-environmental issues. This study uses 19 interviews with farmers along Oregon’s Willamette River, a statewide producer survey, and select interviews with organizations and agencies active in the farming community to examine the...