11 research outputs found
Some ecological factors affecting the input and population level of total and faecal coliforms and salmonella in Twelve Mile Creek, Lake Ontario and sewage waters near St. Catharines, Ontario
Some Ecological Factors Affecting the Input and Population Levels of Total
and Faecal Coliforms and Salmonella in Twelve Mile Creek, Lake Ontario and
Sewage Waters Near St. Catharines, Ontario. Supervisor: Dr. M. Helder.
The present study was undertaken to investigate the role of some
ecological factors on sewage-Dorne bacteria in waters near St. Catharines,
Ontario. Total and faecal coliform levels and the presence of Salmonella
were monitored for a period of a year along with determination of temperature,
pH, dissolved oxygen, total dissolved solids, nitrate N, total phosphate
P and ammonium N. Bacteriological tests for coliform analysis were
done according to APHA Standard Methods by the membrane filtration technique.
The grab sampling technique was employed for all sampling.
Four sample sites were chosen in the Port Dalhousie beach area to
determine what bacteriological or physical relationship the sites had to
each other. The sample sites chosen were the sewage inflow to and the
effluent from the St. Catharines (Port Dalhousie) Pollution Control Plant,
Twelve Mile Creek below the sewage outfall and Lake Ontario at the Lakeside
Park beach. The sewage outfall was located in Twelve Mile Creek, approximately
80 meters from the creek junction with the beach and piers on Lake
Ontario. Twelve Mile Creek normally carried a large volume of water from
the WeIland Canal which was diverted through the DeCew Generating Station
located on the Niagara Escarpment. An additional sample site, which was
thought to be free of industrial wastes, was chosen at Twenty Mile Creek,
also in the Niagara Region of Ontarioo
3
There were marked variations in bacterial numbers at each site and
between each site, but trends to lower_numbers were noted from the sewage
inflow to Lake Ontario. Better correlations were noted between total
and faecal coliform population levels and total phosphate P and ammonium
N in Twenty Mile Creek. Other correlations were observed for other sample
stations, however, these results also appeared to be random in nature.
Salmonella isolations occurred more frequently during the winter and spring
months when water temperatures were minimal at all sample stations except
the sewage inflow. The frequency of Salmonella isolations appeared to be
related to increased levels of total and faecal coli forms in the sewage
effluent. However, no clear relationships were established in the other
sample stations. Due to the presence of Salmonella and high levels of
total and faecal coliform indicator organisms, the sanitary quality of Lake
Ontario and Twelve Mile Creek at the sample sites seemed to be impaired over
the major portion of the study period
Characterization and nutritional study of the heterotrophic bacteria from marine benthic algae.
Miu-kuen Kong.Thesis (M. Ph.)--Chinese University of Hong Kong.Bibliography: leaves 164-186
Studies on Campylobacter fetus subspecies jejuni
The work described in this thesis was principally directed at trying to develop a mouse model for human campylobacteriosis and also at defining the antigenic relationships between the human strains. Human diarrhoeal and normal stool specimens were examined for Campylobacter fetus ss, jejuni by culture on plates of Campylobacter selective medium, incubated at 4
Novel inhibitors of the bacterial de novo purine biosynthesis enzymes, n5-carboxyaminoimidazole ribonucleotide synthetase and mutase
Antibiotic resistance has seen a significant increase during the past decade. The increasing frequency of the drug-resistant bacterial infections has amplified the need for novel antimicrobial agents. De novo purine biosynthesis is one area that has great potential for antibacterial drug development because this pathway is different in microorganisms versus humans. The difference in the pathway is centered on the synthesis and utilization of the purine intermediate N5-carboxy-5-aminoimidazole ribonucleotide (N5-CAIR). Previous studies have shown that N5-CAIR is a key intermediate in purine biosynthesis in bacteria, yeast and fungi, but not in humans. N5-CAIR is synthesized from 5-aminoimidazole ribonucleotide (AIR) by the enzyme N5-CAIR synthetase and it is utilized by N5-CAIR mutase to produce the intermediate 4-carboxy-5-aminoimidazole ribonucleotide (CAIR). In our laboratory we explored both enzymes as potential targets for the design of novel de novo purine biosynthesis inhibitors. Previous studies suggested that the isatin-based inhibitors were promising low micromolar inhibitors of N5-CAIR synthetase. Here, the biological verification of the isatin compounds as potential hits and their kinetic analysis are presented. The second project involves the discovery, kinetic evaluation, molecular modeling, and exploratory synthesis of the first known, selective inhibitor of N5-CAIR mutase
Studies on serological variation among bovine rotaviruses
All 12 field strains of rotavirus used initially to provide virus
stock and convalescent antisera were capable of multiplying in gnotobiotic
Lambs but without inducing diarrhoea. None grew on primary bovine and
ivine embryonic kidney cell cultures nor on MDBK, LLC-MK2 and Vero cell
Lines but all adapted well to growth in roller cultures of MA104 cells
ireated with lOpg/ml of trypsin. Pre-treatment of virus inocula was
essential for further propagation of the virus strains on MA104 cells.Because 4 of 12 original strains were found to contain more than one
rotavirus electrophoretype, the remaining 8 strains were selected for more
letailed serological investigations. Neutralisation tests using
convalescent lamb antisera and hyperimmune rabbit antisera against faecal
ind tissue culture viruses confirmed the presence of two distinct
serotypes; in that they showed more than a 20-fold reciprocal difference
Ln titre and an antigenic relatedness value of less than 5%. When samples
cf infected calf faeces were titrated in hyperimmune antisera to these two
serotypes, four untypable rotaviruses were isolated of which three
belonged to a hitherto unknown third serotype, while the fourth strain
showed a partial relationship to this new serotype.In summary of the 108 calf rotavirus strains examined, no fewer than
JO (74%) including the UK(Compton), Northern Ireland, and Lincoln strains
belonged to serotype 1, one was identified as serotype 2 and three as
serotype 3. Of the remainder, one had a partial relationship to serotype
J while 23 produced insufficient fluorescing foci to enable them to be
characterised fully. Attempts to develop ELISA and HAI tests for the
letection of rotaviruses of serotypes 1 and 2 in diagnostic faecal samples
croved unsuccessful.Examination of the electrophoretypes of rotavirus involved in 30
outbreaks of diarrhoea in calves revealed that one strain usually
predominated in each individual herd, although infection with multiple
strains occurred on 5 of the farms examined. There was no evidence that
jenomic and polypeptide variations exhibited by the calf rotaviruses were
related to their serotypic differences.In experimental calf, infection of ligated gut loops showed that
variations in virulence were obtained with different strains of rotavirus,
ilthough no correlation occurred between virulence and the serotypes used,
fhere was no appreciable difference between faecal and tissue culture
virus in the: ability to infect intestinal epithelial cells and most
rended to favour the ileal (middle and distal) rather than the jejunal
[proximal) parts of the small intestine for replication.The practical importance of indentifying rotavirus serotypes was
:onfirmed by passive cross-protection immunisation experiments in
jnotobiotic lambs. Thus lambs fed with antiserum for three successive
lays and challenged with rotavirus between the first and second feeds
showed good protection against the homologous virus; but there was no
pross-protection; affected lambs excreted the challenge virus at similar
:itres and over the same period as did unprotected control lambs
Biogenic Amines and Food Safety
Biogenic amines are bioactive compounds distributed in foods of all origins. Apart from their fundamental role in many bodily functions, there has recently been great interest in their toxicological potential, much research is being carried out to understand their occurrence related to both desired and undesired fermentative phenomena, chemical spoilage, low hygienic conditions, wrong handling, and criticism about technological factors of process and storage conditions. All these causes can contribute to a higher content of biogenic amines in food, particularly of those hazardous to human health. This book aims to collect scientific studies looking for new tools to limit the over-production of biogenic amines in food, search for new food sources of biogenic amines, and to spotlight the concept of safe food and bioactive amines content
CBRN
"Since 2001, the U.S. Department of Health and Human Services (HHS), Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH) has established performance and design standards for respiratory protective devices (RPDs) to protect against chemical, biological, radiological, and nuclear (CBRN) hazards and toxic industrial chemicals. Prior to 2001, there were no standards for the use of RPDs by U.S. emergency response personnel that covered the full range of expected CBRN threats. Federal regulations require emergency response personnel to use respirators approved by NIOSH for the expected hazards. Equipment performance standards were needed to protect against CBRN threats. Neither industrial nor military respirators provided protection from all potential CBRN respiratory hazards. Several federal agencies partnered to provide research and testing to produce the necessary standards: Department of Justice (DOJ); Department of Homeland Security (DHS); Department of Defense (DoD), U.S. Army Research, Development and Engineering Command (RDECOMa); Department of Commerce (DOC), National Institute for Standards and Technology (NIST); and the Department of Labor (DOL), Occupational Safety and Health Administration (OSHA). The NIOSH RPD approval standards and tests developed for CBRN protections are highly specialized. The advanced CBRN respirators have unique characteristics related to selection, use, and maintenance compared to NIOSH-approved industrial respirators. Due to the enhanced protection afforded by NIOSH-approved CBRN respirators, it is likely that the respirators will also be used in industrial applications. Nationally prominent organizations have identified the need for advice and training on CBRN respirators. Among these are the RAND Corporation, Science and Technology Policy Institute, and the Federal InterAgency Board (IAB) for Equipment Standardization and Interoperability. Responders in several RAND studies clearly expressed the need for guidelines related to personal protective equipment (PPE), including respirators [Bartis et al. 2005; Jackson et al. 2002; Jackson et al. 2004; LaTourrette et al. 2003; Willis et al. 2006]. As early as 2002, RAND reported: One of the clear messages of the conference (December 10, 2001) was that most emergency workers do not believe that they are prepared with the necessary information, training, and equipment to cope with many of the challenges associated with the response to a major disaster such as the World Trade Center attack or for threats associated with anthrax, and similar agents [Jackson et al. 2002]. Another RAND study indicated: In sum, community representatives stressed that a greater amount of training and education must be part of any policy to improve the protection of emergency responders in the line of duty [LaTourrette et al. 2003]. An IAB annual report also underscored the need for guidance: The emergency responder community has a need for guidance and information on the selection, use, and maintenance of CBRN respirators to ultimately reduce incidences of respiratory related injury for nearly 4 million career and volunteer corrections, emergency medical services, firefighting, and law enforcement responders [IAB 2009]. This handbook fills the critical need for authoritative technical information on CBRN RPDs. The information presented will assist any user of CBRN respirators to improve selection, use, and maintenance, but it is particularly useful to those individuals responsible for administering respirator protection programs or developing training programs. The handbook is intended for organizations that use CBRN respirators in emergency response applications (e.g., fire service, law enforcement, emergency medical services, and corrections officers). It does not include information on how to conduct response activities. Others who use CBRN respirators in industrial, public works, construction, utility, and other non-emergency applications will also benefit from the information presented. The information in the following chapters can be used to develop a more effective CBRN respiratory protection program and establish effective training programs in support of other requirements such as relevant National Fire Protection Association (NFPA) and OSHA standards. Relevant NFPA standards include NFPA 472 (Standard for Competence of Responders to Hazardous Materials/ Weapons of Mass Destruction Incidents) and NFPA 473 (Standard for Competencies for EMS Personnel Responding to Hazardous Materials/Weapons of Mass Destruction Incidents). Relevant OSHA and EPA standards include Title 29 Code of Federal Regulations (CFR) 1910.134 (Respiratory Protection) and 1910.120 (Hazardous Waste Operations and Emergency Response), and Title 40 CFR Chapter 1, Part 311 (Worker Protection)." - NIOSHTIC-2NIOSHTIC no. 20052066Suggested citation: NIOSH [2018]. CBRN respiratory protection handbook. By Janssen L, Johnson AT, Johnson JS, Mansdorf SZ, Medici OR, Metzler RW, Rehak TR, Szalajda JV. Pittsburgh, PA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2018-166, https://doi.org/10.26616/NIOSHPUB2018166.Appendix A: CBRN Respirator Standards -- Appendix B: OSHA CBRN Fit Testing Interpretation Letter -- Appendix C: Respiratory Protection Program Samples2018https://doi.org/10.26616/NIOSHPUB201816