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Utilizing waste products from the food production and processing industries.

Waste in the food industry is characterized by a high ratio of product-specific waste. Not only does this mean that the generation of this waste is unavoidable, but also that the amount and kind of waste produced, which consists primarily of the organic residue of processed raw materials, can scarcely be altered if the quality of the finished product is to remain consistent. The utilization and disposal of product-specific waste is difficult, due to its inadequate biological stability, potentially pathogenic nature, high water content, potential for rapid autoxidation, and high level of enzymatic activity. The diverse types of waste generated by various branches of the food industry can be quantified based on each branches' respective level of production. Moreover; the origins of each type of waste and a tabulated overview of the traditional agricultural methods for reusing the waste are discussed. Additionally, alternative methods of waste management have emerged, which target the most important contents of the waste. In conclusion, new possibilities for the utilization of food industry waste are described.

Conservation of Natural Resources↗

Heat shock protein peptides reactive in patients with Behçet's disease are uveitogenic in Lewis rats.

Mycobacterial and homologous human heat shock protein T cell peptide epitopes specific for T lymphocytes in Behçet's disease were investigated for their pathogenicity in Lewis rats. The potential pathogenicity of eight peptides and two controls was assessed by administering the peptides in enriched Freund's adjuvant into the footpads of male Lewis rats. Anterior uveitis which is a major manifestation of Behçet's disease was induced with two out of the four mycobacterial and all four homologous human peptides. The most effective peptides inducing iridocyclitis in 64-75% of rats were peptides with amino acids 336-351 and 136-150, derived from the sequence of the human 60-kD heat shock protein. A few of the rats also showed evidence of focal loss of photoreceptors. These results suggest that selected peptides within heat shock protein 60 kD which function as T cell epitopes in Behçet's disease are capable of inducing uveitis in rats. This supports the view that the peptide T cell determinants may be involved in the pathogenesis of Behçet's disease.

Amino Acid Sequence↗

Location of bung bagging during beef slaughter influences the potential for spreading pathogen contamination on beef carcasses.

Preevisceration carcass washing prior to bung bagging during beef slaughter may allow pooling of wash water in the rectal area and consequent spread of potential pathogens. The objective of this study was to compare protocols for bung bagging after preevisceration washing with an alternative method for bung bagging before preevisceration washing for the potential to spread enterohemorrhagic Escherichia coli, E. coli O157:H7, and Salmonella on carcass surfaces. The study evaluated incidence rates of pathogens in preevisceration wash water (10 ml) samples (n = 120) and on surface (100 cm2) sponge samples (n = 120) in the immediate bung region when bagging occurred before (prewash bagging) and after (postwash bagging) preevisceration washing. Surface sampling from postwash bagging yielded incidence rates of 58.3, 5, and 8.3%, whereas wash water sampling yielded 28.3, 1.7, and 5% for enterohemorrhagic Escherichia coli, E. coli O157:H7, and Salmonella, respectively. Surface sampling from prewash bagging yielded incidence rates of 35, 1.7, and 0%, whereas wash water sampling yielded 18.3, 0, and 8.3% for enterohemorrhagic Escherichia coli, E. coli O157:H7, and Salmonella, respectively. Results of this research indicate that the rectal area is a significant source of pathogen contamination on carcasses and that wash water is an important mechanism for potential transfer of pathogen contamination from the rectal area. Results from this study suggest that bung bagging, as proposed in this study, before (prewash bagging) rather than after (postwash bagging) preevisceration washing was generally more effective in controlling pathogen contamination and potential spread from the rectal area of carcasses.

Abattoirs↗

Chemical and biological characterization of the lipopolysaccharide of the oral pathogen Wolinella recta ATCC 33238.

To investigate the potential pathogenic mechanisms of the oral periodontopathogen Wolinella recta ATCC 33238, we have isolated its lipopolysaccharide (LPS) and determined the chemical composition and selected in vitro biological activities of the molecule. Sodium desoxycholate-polyacrylamide gel electrophoresis revealed the W. recta LPS to be an atypical smooth LPS with short O-antigenic side chains. Chemically the LPS consisted of 47.2% lipid A, 19.6% polysaccharide, 9.0% heptose, 8.5% hexosamine, 3.2% phosphate, and 0.6% 2-keto-3-deoxyoctanoate. The major fatty acids were hexadecanoic acid (25.0%), 3-OH tetradecanoic acid (23.8%), tetradecanoic acid (15.4%), 3-OH hexadecanoic acid (11.6%), and octadecenoic acid (10.9%). Rhamnose constituted 87.8% of the carbohydrates generally associated with the O antigen, with smaller amounts of glucose (5.5%), mannose (4.9%), and an unidentified sugar (1.9%). CD-1 and C3H/HeN macrophages (M phi) exposed to 1 microgram of W. recta LPS per ml released 6.0 and 10.5 ng of prostaglandin E per ml of supernatant, representing 625% and 1,306% of prostaglandin E release by the control (without LPS). Maximum prostaglandin E release occurred in CD-1 M phi exposed to 100 micrograms of LPS per ml and was equivalent to 1,542% of release by the control. Interleukin-1 (IL-1) activities in CD-1 and C3H/HeN M phi exposed to 1 micrograms of LPS per ml were 257% and 1,941% of activities in the control, respectively. Maximum IL-1 release in CD-1 M phi occurred in response to 50 micrograms of LPS per ml and represented a 927% increase over release in the control, while 100 micrograms LPS per ml stimulated maximum IL-1 release in C3H/HeN M phi that was greater than 5,000% of release by the control.

Acid Phosphatase↗

Mycobacterium thermoresistibile: a new pathogen for humans.

The first evidence of the potential pathogenicity of Mycobacterium thermoresistibile is presented. This mycobacterium, initially identified as Mycobacterium gordonae, was isolated repeatedly from sputum, a bronchoscopy specimen. and later, an open lung biopsy. The distinctive characteristics are described, including the unique ability of the organism to grow at 52 degrees C.

Bronchi↗

Evaluation of a one-step surgical preparation technique in dogs.

The efficacy of a 1-step surgical preparation technique for skin of dogs prior to elective ovariohysterectomy was evaluated. Dogs randomly assigned to group 1 (n = 30) had their skin prepared for surgery by use of a 2-step method, whereas the skin of dogs in group 2 (n = 30) was prepared for surgery by use of a commercially available product for a 1-step technique. Culture plates for quantitative bacterial counts were applied to the proposed incision site on dogs under general anesthesia after hair at the site was clipped and vacuumed but before antiseptic was applied. A second quantitative bacterial culture plate was applied to the proposed incision site after completion of the surgical preparation technique. Surgeries were routinely completed, and dogs were evaluated by physical examination the next day and at the time of suture removal (7 to 10 days after surgery) for complications. Postoperative complications were minor and consisted primarily of subcutaneous swelling, which resolved with time. All cultures obtained prior to skin preparation included bacteria or yeast. Sixteen cultures obtained after skin preparation (group 1, n = 11; group 2, n = 5) included bacteria or yeast. The total number of colonies of potential pathogens (Staphylococcus sp and Enterobacteriaceae) on the preparation cultures was 9,339; 4 colonies were counted on the postpreparation cultures. Potential bacterial pathogens, ie Streptococcus intermedius and gram-negative bacteria, were isolated from dogs prepared with the 2-step technique.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Biofilms and the survival of opportunistic pathogens in recycled water.

Microorganisms are likely to develop an organic film on pipes, water reservoirs and filters used for waste water reclamation during extended missions in space. These biofilms can serve to protect and concentrate potentially pathogenic microorganisms. Our investigation has emphasized the survival strategy of opportunistic pathogenic bacteria in distilled water. Pseudomonas aeruginosa and Staphylococcus aureus were used as test organisms. Cultures were incubated at 10 degrees, 25 degrees, and 37 degrees C. No viable Staphylococcus cells were detected after the first week of incubation. P. aeruginosa, however, survived in distilled water up to 5 months at all three temperatures tested. The starved cells were able to form a biofilm layer on stainless steel. The cells exhibited a negative surface charge. The charge may be involved in the adhesion of this bacterium to metal substrata. We are currently investigating the importance of adhesion in the survival of this and other potential human pathogens found in water recycling systems.

Bacterial Adhesion↗

Therapy of nosocomial pneumonia.

HAP remains a major cause of morbidity and mortality among hospitalized patients. Although early appropriate therapy results in improved outcomes, the cause of HAP frequently is not known at the time antimicrobial therapy is initiated. Most cases of HAP result from microaspiration of oropharyngeal secretions previously colonized with pathogenic bacteria, and the spectrum of potential pathogens is broad. Taking several factors into account can narrow this spectrum, including severity of illness, length of stay before the onset of pneumonia, and presence of risk factors for specific pathogens. When therapy has been initiated, follow-up of microbial studies and careful monitoring of the patient's course is important. The clinical improvement, even when therapy is appropriate, frequently takes days; therapy should not be changed for the first 2 to 3 days unless frank deterioration is noted. Patients who fail to respond or experience clinical deterioration should be re-examined carefully, and thought should be given to the possibility of other noninfectious processes.

Anti-Bacterial Agents↗

Regulation of depolarizing GABA(A) receptor-mediated synaptic potentials by synaptic activation of GABA(B) autoreceptors in the rat hippocampus.

The role of GABA(B) autoreceptors in the regulation of GABA(A) and GABA(B) receptor-mediated inhibitory post-synaptic potentials (IPSPs) during repetitive synaptic activation has been established. In the present study the role of these receptors in the regulation of depolarising GABA(A) receptor-mediated synaptic potentials (DPSP(A)s) in the CA1 region of the hippocampus is documented. Following blockade of AMPA and NMDA receptor-mediated synaptic excitation, DPSP(A)s could be evoked by a single stimulus. The size of this response was enhanced by increasing the stimulus number (1-10 shocks) or stimulus frequency (10-100 Hz). Conversely, the amplitude of the DPSP(A) was dramatically reduced by a priming pulse (single shock) or priming burst (four shocks) delivered 200 ms beforehand. This activity-dependent depression was eliminated by the GABA(B) receptor antagonist CGP 35348 (1 mM). As such, GABA(B) autoreceptor-mediated regulation of DPSP(A)s prevented a pronounced, potentially epileptogenic, DPSP(A) from occurring during theta burst stimulation. Thus, during repetitive stimulation, activation of GABA(B) autoreceptors not only enables a transient reduction in GABA(A) receptor-mediated synaptic inhibition sufficient to enable NMDA receptor-dependent synaptic plasticity [Davies, C.H., Collingridge, G.L., 1996. J. Physiol. 496.2, 451-470] but also prevents the development of a potentially pathogenic depolarising GABA-mediated synaptic potential.

Animals↗

Meningococcal pathogenesis: at the boundary between the pre- and post-genomic eras.

Meningococcal disease remains an important public health burden worldwide and, indeed, cause of death, particularly in poorer countries. The rapidly progressive nature of infections means that antibiotic therapy often comes too late. Vaccines are of limited efficacy in infants, one of the most vulnerable age groups, and do not exist for bacteria of serogroup B. Hence, much remains to be achieved in terms of vaccine design and the understanding of the pathogenesis of meningococcal disease. The causative bacterium, Neisseria meningitidis, is usually a commensal of the nasopharynx. Factors that lead to the invasion of the bloodstream, often followed by the crossing of the blood-brain barrier and meningitis, may be partly host- and partly bacterium-dependent, but are ill-understood. It is hoped that, taken together with the fundamental knowledge gained from biochemical and genetic studies, the huge amount of new information made available with the recent publication of the genome sequences will help to unlock more of the secrets of the lifestyle and pathogenic potential of this still poorly understood pathogen.

Bacterial Vaccines↗

New views on periodontal microbiota in special patient categories.

The microorganisms in periodontitis of special patient categories have been only partially elucidated. The periodontitis microbiota of HIV-infected individuals, cancer patients on myelosuppressive therapy, and persons with other medical disorders includes common suspected periodontal pathogens as well as enteric rods, pseudomonads, staphylococci and yeasts. Failing implants also may be associated with classical periodontal pathogens as well as primarily nonoral potential pathogens. Refractory periodontitis in systemically healthy adults can show a great variety of oral and nonoral organisms. The frequent occurrence of unusual periodontal organisms in special patient categories may be due to a weakened host response and/or usage of various chemotherapeutic regimens. The unusual organisms may contribute to progressive periodontitis and in leukemia patients may even give rise to life-threatening systemic manifestations. The primary therapeutic goal in special periodontitis patients is control of pathogens and amid the wide range of pathogenic microfloras, an effective treatment strategy should include a comprehensive microbiological analysis, especially if systemic antimicrobial therapy is contemplated.

Bacteria↗

Bacterial colonization of toys in neonatal intensive care cots.

OBJECTIVES: To investigate the bacteria and fungi contaminating toys in neonatal intensive care unit (NICU) cots, the colonization rates, and factors that influence them. METHODS: A cross-sectional, longitudinal bacteriologic survey of all toys in the cots of infants in an NICU. All the toys in an infant's cot were cultured weekly for 4 weeks. Data were collected on the infant's postnatal age, the type of cot, whether humidity was added, characteristics of the toy, and any infant infections. RESULTS: Over the 4-week period, there were 86 cultures from 34 toys of 19 infants. Bacteria were grown from 84/86 (98%): 84 of the cultures grew coagulase-negative Staphylococcus, 50 Micrococcus sp, 21 Bacillus sp, 13 methicillin-resistant Staphylococcus aureus, 12 diphtheroids, 4 group B streptococcus, 3 S aureus, 3 nonhemolytic streptococci, 3 group D streptococci, 4 alpha-hemolytic streptococci, and 2 coliforms. None grew fungi. The colonization rate did not differ with cot type, presence of humidity, size of the toy, toy fiber length, or the fluffiness score. Eight (42%) of the infants had positive blood culture results and 5/8 of the isolates (63%) were of the same type as that colonizing their corresponding toy. IMPLICATIONS: With time, all the toys in NICU cots became colonized with bacteria. Many were potentially pathogenic. Toys may be reservoirs for potential infantile nosocomial sepsis. infant, newborn, toys, infection, neonatal intensive care.

Australia↗

Infectious disease serologic survey in free-ranging Venezuelan anacondas (Eunectes murinus).

Reptiles can harbor pathogenic microorganisms asymptomatically and serve as potential reservoirs of infection for humans, domestic animals, and other reptiles. Infectious diseases are also problematic for free-ranging reptile populations and are an important consideration in reptile reintroduction and translocation projects. There have been limited serologic studies of free-ranging reptiles for evidence of exposure to potential pathogens. In the present study, serum or plasma samples from five male and five female free-ranging Venezuelan anacondas (Eunectes murinus) were screened for antibodies to eastern, western, and Venezuelan equine encephalitis viruses, vesicular stomatitis virus, ophidian paramyxovirus, 19 Leptospira interrogans serovars, and Cryptosporidium serpentes. Antibodies to these agents were not detected, or antibody titers were low and possibly nonspecific. These results for the limited number of anacondas surveyed suggest that they do not serve as significant reservoirs for these infectious agents at this location.

Animals↗

Cryptosporidium parvum in children with diarrhea in Zulia State, Venezuela.

The prevalence and importance of Cryptosporidium parvum as a causal agent of acute diarrhea among pediatric patients from Zulia State, Venezuela was assessed. Single stool specimens were collected from 310 children 0-60 months of age with acute diarrheal disease who were admitted to three public hospitals and from 150 comparable control children without gastrointestinal symptoms who were seen as outpatients. Cryptosporidium parvum oocysts were identified in 35 (11.2%) of 310 children with diarrhea and the coccidium was the single detectable pathogen in only 12 (34.2%). Other potential pathogenic parasites were present in most of the patients shedding oocysts (23 of 35, 65%). In nondiarrheal control children, oocysts were identified in nine (6%) of 150. The data suggest that C. parvum is relatively highly endemic in children 0-60 months of age in Zulia State and that although C. parvum may be an important pathogen associated with diarrhea, it may be a cause of only a small proportion of diarrheal episodes.

Acute Disease↗

Effects of amoxicillin and cefdinir on nasopharyngeal bacterial flora.

OBJECTIVE: To compare the effects of cefdinir (14 mg/kg per day) and amoxicillin (90 mg/kg per day) antimicrobial therapy on the nasopharyngeal flora of children with acute otitis media. DESIGN: Nasopharyngeal cultures for aerobic and facultative bacteria were obtained before therapy and 2 to 4 days after completion of therapy. SETTING: Outpatient clinic. PATIENTS: Fifty children, aged 7 months to 5 years 4 months. MAIN OUTCOME MEASURES: After completion of therapy, 22 (88%) of the 25 patients treated with cefdinir and 16 (64%) of the 25 patients treated with amoxicillin were considered clinically cured (P<.05). A significant reduction in the number of all isolates occurred following therapy in those treated with cefdinir (36 vs 71, P<.01) or with amoxicillin (56 vs 73, P<.05). However, the total number of isolates recovered after therapy was significantly lower in those treated with cefdinir (36) compared with those treated with amoxicillin (56) (P<.01). RESULTS: The recovery of potential pathogenic organisms (eg, Streptococcus pneumoniae, Staphylococcus aureus, beta-hemolytic streptococci, Haemophilus species, and Moraxella catarrhalis), as well as penicillin-resistant bacteria, was lower following completion of therapy in the cefdinir group (6 pathogens, including 5 that were penicillin resistant), compared with the amoxicillin group (27 pathogens, including 16 that were penicillin resistant) (P<.01). CONCLUSION: This study illustrates the greater ability of cefdinir compared with amoxicillin to reduce the number of potential nasopharyngeal pathogens as well as penicillin-resistant bacteria in children with acute otitis media.

Acute Disease↗

The importance of Campylobacter jejuni to the meat industry: a review.

Campylobacter jejuni is a microorganism that only recently has been implicated in gastroenteritis in humans. As appropriate methods used for detection of the bacterium have been developed, the rates of illness caused by the pathogen were found to approach or surpass those attributed to Salmonella. Substantial evidence has been gathered to document that the route for human infection is through the ingestion of adulterated food and drink. Some slaughter animals harbor this potential pathogen among the intestinal flora and, consequently, transfer of the organism to carcasses and to the resulting meat products does occur. The most frequently implicated meat is poultry, with an incidence of recovery of C. jejuni from the store-bought poultry meat reported to be at least 50%. Red meat from slaughter animals have also yielded this bacterium from carcasses, but at lower incidence levels. Foodborne disease has been associated most frequently with the ingestion of raw milk, but poultry, hamburger, and other foods have all been implicated as potential sources. However, cause and effect relating the presence of C. jejuni in meat and human gastroenteritis has not been demonstrated. Additional research is needed to determine whether C. jejuni isolated from meat causes gastroenteritis and whether all strains of the organism are virulent. Recognition of C. jejuni as a potential meatborne pathogen by the meat industry is necessary, and appropriate sanitary practices to prevent passage of the organism through meat products should be implemented.

Adult↗

PCR detection of pathogenic Leptospira genomospecies targeting putative transcriptional regulator genes.

The genus Leptospira comprises multiple genomospecies that demonstrate varied pathogenic potential. The availability of rapid and precise diagnostic procedures to differentiate pathogenic from nonpathogenic Leptospira spp. is therefore essential to prevent an otherwise easily treatable malaise from developing into a life-threatening disease. In this report, we conducted an investigation on the diagnostic potential of Leptospira genes encoding putative transcriptional regulators. While PCR primers derived from transcriptional regulator gene la1137 recognized all 24 pathogenic Leptospira strains representing seven species, those from la1937, la3231, la3825, and la4130 detected 19 of the 24 Leptospira strains. However, none of these primers reacted with four nonpathogenic Leptospira species or other common bacteria. The putative transcriptional regulator genes la1137, la1937, la3231, la3825, and la4130 are present in pathogenic Leptospira strains, making them potential targets for diagnostic applications. Further characterization of these genes and their proteins may help elucidate the molecular mechanisms of leptospiral virulence and pathogenicity and pave the way for potential development of novel control strategies against leptospirosis.

Genes, Regulator↗

Molecular typing of paired bacterial isolates from the adenoid and lateral wall of the nose in children undergoing adenoidectomy: implications in acute rhinosinusitis.

OBJECTIVE: Recent studies have suggested that the origin of bacteria that enter the lateral wall of the nose and paranasal sinuses arise from the nasopharynx. The purpose of this study was to compare the molecular biological profiles of potential pathogens found in the nasopharynx and lateral wall of the nose concomittantly in children undergoing surgery for upper respiratory tract disease. STUDY DESIGN AND SETTING: Fifty-two children undergoing adenoidectomy for either tonsillectomy or adenoidectomy (hypertrophy) or otitis media with effusion were studied. Bacterial cultures were taken from the crypts of the adenoids and from the lateral wall of the nose under endoscopic control after sterilization of the vestibule and inferior turbinate. Routine cultures of these areas were performed in the bacteriology laboratory of the Children's Hospital of Buffalo. RESULTS: Bacterial pathogens were isolated from 79% of adenoids and 46% of lateral walls of the nose. Molecular typing of pairs of nontypable Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis revealed that in 16 of 18 pairs (89%) the identical strain was present in both sites simultaneously. CONCLUSIONS: These results support the concept that when potential bacterial pathogens that may cause acute bacterial rhinosinusitis are found concomitantly in the nasopharynx and lateral wall of the nose, they are usually identical.

Acute Disease↗