Wool Swabs Research Articles

PetSavers research

Rebecca Verhoven BSc (Hons) RVN, and lecturer Kat Hart, report on their PetSavers-funded research undertaken while Rebecca was a student vet nurse – Cotton wool versus non-woven gauze swabs: comparatively, which is more efficacious for minimizing the preoperative microbial load on the ovariohysterectomy surgical site in bitches?

Clinical features of endophthalmitis clusters after cataract surgery and practical recommendations to mitigate risk: systematic review.

Intraocular transmission of exogenous pathogens in cataract surgery can lead to endophthalmitis. This review evaluates the features of endophthalmitis clusters secondary to pathogen transmission in cataract surgery. Articles reporting on pathogen transmission in cataract surgery were identified via searches of Ovid MEDLINE, EMBASE, and Cochrane CENTRAL, and a total of 268 eyes from 24 studies were included. The most common source of infectious transmission was attributed to a contaminated intraocular solution (ie, irrigation solution, viscoelastic, or diluted antibiotic; n = 10). Visual acuity at presentation with infectious features was 1.89 logMAR (range: 1.35 to 2.58; ∼counting fingers) and 1.33 logMAR (range: 0.04 to 3.00; Snellen: ∼20/430) at last follow-up. Patients with diabetes had worse outcomes compared with patients without diabetes. The most frequently isolated pathogen from the infectious sources was Pseudomonas sp. (50.0%). This review highlights the various routes of pathogen transmission during cataract surgery and summarizes recommendations for the detection, prevention, and management of endophthalmitis clusters.

Devising criteria for the authenticity of historical cold weapons based on X-ray fluorescence analysis of their surface

This paper reports the results of studying the chemical composition of the surface of 4 objects of cold weapons of the 19th and early 20th centuries, made of iron – bayonet knives and sabers. This makes it possible to establish the signs of authenticity of cold weapon samples made of iron in that chronological period. An authentic procedure has been proposed for examining the chemical composition of the surface of historical objects of cold weapons by rubbing the samples with cotton wool swabs and their subsequent investigation. This makes it possible to explore objects of cold weapons, whose size is large, as well as simplify the very procedure for studying objects of historical and cultural value. Using the X-ray fluorescent chemical analyzer Expert Mobile, chemical elements were found at the surface of samples of cold weapons made of iron. The presence of such elements is the result of the process of re-crystallization and self-purification of metal during a long history of its life. Elements found in almost every rubbing sample were identified: calcium, ferrum, zinc, cuprum, and chlorine. The studies of cold weapons samples testify to the heterogeneity of the composition of patina formations on their surface, which confirms the authenticity of ancient objects. In addition, the studies have shown a difference in the chemical composition of surface layers of different parts of individual samples of antique cold weapons, which may indicate different times or different technology for their manufacture. The fluorescence spectra of the obtained rubbing of individual samples of cold weapons were compared with "pure" material, which made it possible to identify elements removed from the surface of objects. The study results are important indicators to confirm the authenticity of cultural monuments and the technology of their manufacture in the past.

Alteration on redox status in saliva of microcephaly children

Microcephaly is described as a reduction of the head circumference, due to the premature fusion of the bones of the skull, preventing the brain from growing normally and reaching its maximum development. This condition may result in neurological disorders, phonation and chewing dysfunction, dysphagia and risk of malnutrition. This alteration contributes to oral hygiene impairment, and continuous uses of the antipsychotic and anticonvulsant medication. Thus, the purpose of this study was to evaluate if microcephaly modified redox balance in saliva. Our hypothesis is that in the microcephalic patient's salivary oxidative stress is lower because of the increase in antioxidant defenses. The study included 13 patients with microcephaly (microcephalic group – MC) and 12 patients without neurological disorders (normocephalic group – NC), from zero to ten years old, no edentulous. Saliva was collected using a cotton wool swab, placing it on the child's mouth floor. After centrifugation, supernatants were fractionated and stored at -80 °C for analyses. Lipid oxidative was evaluated by TBARS methods, total antioxidant capacity by the ferric reducing ability (FRAP) assay, uric acid (UA) was quantified by modified Trinder reaction, and superoxide dismutase activity (SOD) by inhibition of the pyrogallol auto-oxidation. Total protein was measured using the method of Lowry. Compared to NC group, TBARS was significantly lower in MC group, while FRAP, UA and SOD were higher. Our hypothesis was confirmed. MC patients have lower salivary oxidative stress, due to increased oxidant defenses.

The prevalence, risk factors and antifungal sensitivity pattern of oral candidiasis in HIV/AIDS patients in Kumba District Hospital, South West Region, Cameroon.

IntroductionOral candidiasis is one of the most common opportunistic infection in HIV/AIDS patient and it is caused by Candida species. The low absolute CD4+T-lymphocyte count has traditionally been cited as the greatest risk factor for the development of Oral Candidiasis. The aim of this study was to identify Candida species isolated from the oral cavity of HIV/AIDS patients, to determine their in vitro antifungal susceptibility and to investigate the possible risk factors associated with oral candidiasis.MethodsThis was a hospital based cross sectional study that was carried out for a period of 3 months amongst HIV/AIDS patients in Kumba District Hospital, whether on HAART or not. Mouth swabs were collected from 378 participants using sterile cotton wool swabs and 5ml venous blood were collected for determination of CD4 cell. Candida species were isolated and identified. Antifungal sensitivity testing was performed using modified kirby-bauer susceptibility testing technique.ResultsCandida species were present in 42.86% of the samples and Candida albicans was the most prevalent (60.2%) amongst the six Candida isolates identified, followed by Candida glabrata (16.9%), Candida krusei (12.3%), Candida tropicalis (6.4%), Candida parapsilosis (2.3%) and Candida pseudotropicalis (1.8%). Pregnancy, oral hygiene and antibiotic usage were significantly associated with oral candidiasis in HIV/AIDS patients (P<0.05). Oral candidiasis was mostly frequent in HIV/AIDS patients between 21-40 years. A CD4 cell count less than 200 cells/μl was a significant risk factor for acquiring oral candidiasis in HIV/AIDS patients (P<0.001). Nystatin was the most sensitive drug (83.6%) meanwhile ketonazole was the most resistant drug (29.2%), followed by fluconazole (24.6%) to all oral Candida isolates.ConclusionOral Candida colonization occurs more frequently in HIV/AIDS patients and the is a need for the government to implement regular checks for opportunistic infections in HIV/AIDS patients, including oral candidiasis in HIV/AIDS patients to monitor disease progression and prevent subsequent complications such as candidemia and diarrhea.

Influence of Horse and Rider on Stress during Horse-riding Lesson Program.

The present study aims to confirm the influence of a horse-riding lesson program (HRLP) on the stress level of horses and riders by respectively analyzing their salivary cortisol concentration. Twenty-four healthy horses and 23 riders participated in this study. The horses were randomly classified into two groups for the horse riding lesson program: Class 1 (for the beginner lesson) and Class 2 (for the intermediate lesson). The Class 1 group consisted of 12 horses and 12 riders, while the Class 2 group consisted of 12 horses and 11 riders. Salivettes cotton wool swabs were used for saliva collection and the saliva analyses were conducted using a two-way analysis of variance for repeated measures with SAS version 8. As for the results, the average salivary cortisol concentration of all horses before HRLP significantly increased compared to the baseline (p<0.001) while it decreased after the HRLP. The results of the salivary cortisol concentration of the riders were similar to the horses’ results. However, there was no difference during the HRLP between Class 1 and Class 2 in the horse or rider groups. The results suggest that the HRLP did not influence the stress level of the horses or riders. Thus, this study provides the necessary information and guidelines for future studies on stress in horses during riding and gives insight into better horse welfare and management options.

Safer? Healthier?

I might have been, but was not, alarmed last night when hearing on my car radio about a piece of research that had revealed the considerable danger of Escherichia coli acquired from car steering wheels. A university researcher had been to a car park with some cotton wool swabs which, taken back to the lab and plated out on nutrient medium, had revealed “astronomical” numbers of E. coli cells in 9 out of 10 vehicles. “Although E. coli can be harmless,” the reporter said, “it also causes not only severe gastrointestinal infections but also life-threatening conditions such as kidney failure.”

Aerobic bacterial flora of the normal conjunctiva at high altitude area of Shimla Hills in India: a hospital based study.

To study the normal aerobic conjunctival flora in lower to mid Himalayan region of Shimla Hills. Samples from normal conjunctiva of 200 individuals above the age of 13 years who visited Indira Gandhi Medical College Hospital Shimla for refraction or cataract surgery were taken by anaesthetising the conjunctival sac with sterile 4% Xylocaine solution. Samples were obtained by gently rubbing lower fornix with a sterile cotton wool swab moistened with normal saline and keeping the eye lids wide apart to avoid contamination from lid margins. It was immediately inoculated in Brain Heart infusion and subjected to standard aerobic culture and identification techniques. Totally, 72 eyes (36%) conjunctival sacs were sterile. Predominant aerobes isolated were Staphylococcus spp. in 120 (60%) followed by Haemophilus in 16 (8%), diphtheroids in 10 (5%), and Escherichia.coli (E. coli) in 4 (2%). A single aerobe was isolated from 98 eyes (49%) while 30 eyes (15%) yielded more than 1 aerobe. Staphylococcus epidermidis (S. epidermidis) was the most common bacterium, found alone in 58 eyes (29%) and in combination with another aerobe in 30 eyes (15%), followed by Staphylococcus aureus (S. aureus) in 18 (9%) and 10 eyes (5%) respectively. S. epidermidis is the most common commensal organism followed by Haemophilus species. diphtheroids occupied the third position which otherwise are found more abundantly in literature. Pathogens like S. aureus, Staphylococcus citreus and E. coli were also found. Therefore, preoperative administration of topical broad spectrum antibiotics is extremely important in prophylaxis against ocular infection. The variation in microflora of normal conjunctiva in this part of world can be attributed to geographical, climatic and ethnic characteristics of the population under study.

Swabs as a Tool for Monitoring the Presence of Norovirus on Environmental Surfaces in the Food Industry

Human norovirus (HuNoV), which causes gastroenteritis, can be transmitted to food and food contact surfaces via viruscontaminated hands. To investigate this transmission in food processing environments, we developed a swabbing protocol for environmental samples, evaluated the stability of HuNoV in the swabs, and applied the method in the food industry. Swabs made of polyester, flocked nylon, cotton wool, and microfiber were moistened in either phosphate-buffered saline (PBS) or glycine buffer (pH 9.5) and used to swab four surfaces (latex, plastic, stainless steel, and cucumber) inoculated with HuNoV. HuNoV was eluted with either PBS or glycine buffer and detected with quantitative reverse transcription PCR. HuNoV recoveries were generally higher with an inoculation dose of 100 PCR units than 1,000 PCR units. The highest recoveries were obtained when surfaces were swabbed with microfiber cloth moistened in and eluted with glycine buffer after a HuNoV inoculation dose of 100 PCR units: 66% ± 18% on latex, 89% ±2% on plastic, and 79% ±10% on stainless steel. The highest recovery for cucumber, 45% ±5%, was obtained when swabbing the surface with microfiber cloth and PBS. The stability of HuNoV was tested in microfiber cloths moistened in PBS or glycine buffer. HuNoV RNA was detected from swabs after 3 days at 4 and 22°C, although the RNA levels decreased more rapidly in swabs moistened with glycine buffer than in those moistened with PBS at 22°C. In the field study, 172 microfiber and 45 cotton wool swab samples were taken from environmental surfaces at three food processing companies. Five (5.6%) of 90 swabs collected in 2010 and 7 (8.5%) of 82 swabs collected in 2012 were positive for HuNoV genogroup II; all positive samples were collected with microfiber swabs. Three positive results were obtained from the production line and nine were obtained from the food workers' break room and restroom areas. Swabbing is a powerful tool for HuNoV RNA detection from environmental surfaces and enables investigation of virus transmission during food processing.

Antibiogram of Bacterial Isolates from the Anterior Nares and Hands of Health Care Workers in University of Uyo Teaching Hospital (UUTH) Uyo, AkwaIbom State, Nigeria

Hands and anterior nares of Health Care Workers may serve as sources for transmission of pathogens causing nosocomial infection. The importance of hands in the transmission of nosocomial infection is known worldwide. However, it is difficult to induce hand washing behavior in health-care workers. This work is designed to ascertain the frequency of bacterial colonization and the antibiotic sensitivity pattern of the isolates from the anterior nares and hands of healthcare workers in University of Uyo Teaching Hospital (UUTH). Sterile cotton wool swabs, which were pre-moistened in sterile normal saline, were used to swab the anterior nares, and another used to swab the interdigital spaces of both hands of the participants. The samples were cultured on Mannitol salt agar, Blood agar and MacConkey agar. The plates were incubated at 35°C for 24-48 hrs. The bacterial isolates were identified and antibiotic susceptibility testing carried out on them using CLSI standard. Out of the 60 samples analysed (30 nasal and hand swabs), 48 (80%) yielded bacterial growth and 12 (20%) showed no bacterial growth. Of the 48 isolates, 46 (95.8%) were identified as Staphylococcus spp and 2 (4.2%) were identified as Gram negative bacteria (Escherichia coli and Proteus mirabilis). Out of the 46 Staphylococcal isolates, 30 (65.2%) were coagulase positive and 16 (34.8%) were coagulase negative. Out of the 30 coagulase positive Staphylococcus spp, 12 (40%) were found to be Methicillin resistant, and one of the Gram negative bacteria isolated (Proteus mirabilis) was extended spectrum beta lactamase producing. Also, of the 48 Staphylococcal isolates, 5 (10.4%) were inducible Clindamycin resistant. Staphylococcus aureus was found to be sensitive to Clindamycin (80%), followed by Ciprofloxacin (77%), Amoxicillin clavulanic acid (73.3%), Oxacillin (60%), Erythromycin (43%), Ceftriaxone (40%) and Trimethoprim Sulphamethoxazole (23.3%). On the other hand, Staphylococcus epidermidis was found to be sensitive to Ciprofloxacin (81%), Clindamycin (70%), Amoxicillin Clavulanic Acid (68.8%), Erythromycin (56.2%), Ceftriaxone (19%) and Trimethoprim Sulphamethoxazole (2.5%). E. coli was 100% sensitive to Ceftriaxone, Ciprofloxacin, Gentamycin, Ceftazidime and Cefotaxime, and Proteus mirabilis showed 100% sensitivity to Ceftriaxone, Amoxicillin clavulanic acid, Gentamycin and Cefotaxime. Since hands and anterior nares of health care worker attending to patients could be a source of transmission of nosocomial infection with its attendant consequences in patients care, it will be helpful to screen them regularly as a measure towards the prevention and control of hospital acquired infection.

Quality assurance testing of an explosives trace analysis laboratory — Further improvements to include peroxide explosives

The Forensic Explosives Laboratory (FEL) operates within the Defence Science and Technology Laboratory (DSTL) which is part of the UK Government Ministry of Defence (MOD). The FEL provides support and advice to the Home Office and UK police forces on matters relating to the criminal misuse of explosives. During 1989 the FEL established a weekly quality assurance testing regime in its explosives trace analysis laboratory. The purpose of the regime is to prevent the accumulation of explosives traces within the laboratory at levels that could, if other precautions failed, result in the contamination of samples and controls. Designated areas within the laboratory are swabbed using cotton wool swabs moistened with ethanol:water mixture, in equal amounts. The swabs are then extracted, cleaned up and analysed using Gas Chromatography with Thermal Energy Analyser detectors or Liquid Chromatography with triple quadrupole Mass Spectrometry. This paper follows on from two previous published papers which described the regime and summarised results from approximately 14years of tests. This paper presents results from the subsequent 7years setting them within the context of previous results. It also discusses further improvements made to the systems and procedures and the inclusion of quality assurance sampling for the peroxide explosives TATP and HMTD. Monitoring samples taken from surfaces within the trace laboratories and trace vehicle examination bay have, with few exceptions, revealed only low levels of contamination, predominantly of RDX. Analysis of the control swabs, processed alongside the monitoring swabs, has demonstrated that in this environment the risk of forensic sample contamination, assuming all the relevant anti-contamination procedures have been followed, is so small that it is considered to be negligible. The monitoring regime has also been valuable in assessing the process of continuous improvement, allowing sources of contamination transfer into the trace areas to be identified and eliminated.

Bakterielles Keimspektrum bei kindlichen Tränenwegsstenosen

Connatal lacrimal duct stenosis (cLDO) commonly causes purulent bacterial dacyrocystitis. The recommended treatment of choice is up to the sixth month of life a conservative antimicrobiological therapy. After the sixth month lacrimal duct irrigation with silicone tube intubation remains the gold standard. Our purpose was to analyse the current bacterial spectrum in cLDO and to compile a bacterial resistogram in order to specify antimicrobiological therapy. 66 samples from the lacrimal duct of 6- to 16-month-old children (41 female, 25 male) were obtained by collecting the refluxing liquids with cotton wool swabs after irrigation of the lacrimal drainage system with sterile saline during lacrimal duct surgery. Cultures were incubated aerobically and anaerobically and the infectious agents were isolated. Sensitivity testing was performed for each isolate, testing 8 different commonly used local antibiotics. Data were statistically analysed using SPSS. Cultures were positive in cLDO in 97 %, showing co-colonisation in 87 % with up to five bacterial strains. Gram-positive bacteria were seen in 72 % of the isolates in cLDO with Streptococcus pneumoniae (31 %) being the most abundant strain, followed by Staphylococcus aureus (13 %) and S. epidermidis (13 %). In 85 % of the samples at least one Gram-negative rod was present, most often Branhamella (12 %), followed by Haemophilus influenzae (11 %). Sensitivity testing revealed chloramphenicol, fusidic acid and ciprofloxacin/levofloxacin to be the most effective drugs in cLDO, whereas erythromycin and gentamycin turned out to be insufficient in treating cLDO. Bacterial colonisation plays a crucial role in cLDO, showing a positive culture in 97 % with frequent co-colonisation of several bacterial strains (often in combination with at least one Gram-negative strain). The sampling of a microbiological probe of the lacrimal duct is recommended at least in therapy-refractory cases. Current bacteria in cLDO can be effectively treated with chloramphenicol, fusidic acid and ciprofloxacin. The commonly used antibiotics erythromycin and gentamicin are inappropriate as monotherapeutics.

Immunocytochemical examinations of biological traces on expanding bullets (QD–PEP)

When a crime victim has been injured with several different objects, it is of central importance for the forensic investigation to be able to show which object caused which injury, especially if one of the injuries was lethal. In cases of bullet penetration wounds it is often not possible to find such evidence. However, immunocytochemical investigations can accurately match a victim's injury to a particular bullet path through the body. In cases where expanding bullets have been used and the heart or liver has been struck by a projectile, it can be shown that the cells remaining on the bullet stem from those particular organs. In this case the specific cytological evidence was established by means of marking heart- and liver-specific tissue proteins with appropriate antibodies (cardiac troponin I and HepPar 1) followed by disclosure with an appropriate chromogen. Thus, in principle, cells can be used as evidence after being extracted from the projectiles by either damp cotton–wool swabs or adhesive trace evidence tape. Because of the specificity of the used immunocytochemical antibodies, finding evidence of an antigen on a particular projectile proves that it was the object that injured the organs.

Quality Assurance Testing of an Explosives Trace Analysis Laboratory––Further Improvements

The Forensic Explosives Laboratory (FEL) operates within the Defence Science and Technology Laboratory (DSTL) which is part of the UK Government Ministry of Defence (MOD). The FEL provides support and advice to the Home Office and UK police forces on matters relating to the criminal misuse of explosives. During 1989 the FEL established a weekly quality assurance testing regime in its explosives trace analysis laboratory. The purpose of the regime is to prevent the accumulation of explosives traces within the laboratory at levels that could, if other precautions failed, result in the contamination of samples and controls. Designated areas within the laboratory are swabbed using cotton wool swabs moistened with ethanol water mixture, in equal amounts. The swabs are then extracted, cleaned up and analyzed using Gas Chromatographs with Thermal Energy Analyzer detectors. This paper follows on from a previous published paper describing the regime and summarizing subsequent results from approximately 6 years of tests. Lessons learned and improvements made over the period are also discussed. Monitoring samples taken from surfaces within the trace laboratories and trace vehicle examination bay have, with few exceptions, revealed only low levels of contamination, predominantly of RDX. Analysis of the control swabs, processed alongside the monitoring swabs, has demonstrated that in this environment the risk of forensic sample contamination, assuming all the relevant anti-contamination procedures have been followed, is so small that it is considered to be negligible. The monitoring regime has also been valuable in assessing the process of continuous improvement, allowing sources of contamination transfer into the trace areas to be identified and eliminated.

SURVEY OF STAPHYLOCOCCUS ISOLATES AMONG HOSPITAL PERSONNEL, ENVIRONMENT AND THEIR ANTIBIOGRAM WITH SPECIAL EMPHASIS ON METHICILLIN RESISTANCE

The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion broth. Subcultures were done onto blood agar and MacConkey’s agar. Isolates were identified by standard methods up to species level. Antimicrobial susceptibility test was performed according to standardized disc diffusion Kirby-Bauer method. Each of the isolates was screened for methicillin resistance using oxacillin disc on Mueller Hinton agar plate followed by MIC for methicillin and cefoxitin susceptibility test by disc diffusion method. Sixty five out of 205 strains (31.7%) were Staphylococcus spp. and all of them were coagulase negative. Most of the strains belonged to S. epidermidis 49.23% (32/65) followed by S. saprophyticus 26.15% (17/65). Maximum isolates of S. epidermidis were from anterior nares 28.12% (9/32 strains of S. epidermidis). Highest number of methicillin resistant coagulase negative strains (3/9, 33.33%) were isolated from stethoscope of multidisciplinary cardiac unit ward followed by carriers in the anterior nares (2/9, 22.22%). Methicillin resistant coagulase negative staphylococci are prevalent in anterior nares of hospital personnel and in the hospital environment thereby providing a definite source for hospital acquired infection. All isolates were sensitive to vancomycin, ciprofloxacin and amikacin.

Survey of Staphylococcus isolates among hospital personnel, environment and their antibiogram with special emphasis on methicillin resistance

The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion broth. Subcultures were done onto blood agar and MacConkey's agar. Isolates were identified by standard methods up to species level. Antimicrobial susceptibility test was performed according to standardized disc diffusion Kirby-Bauer method. Each of the isolates was screened for methicillin resistance using oxacillin disc on Mueller Hinton agar plate followed by MIC for methicillin and cefoxitin susceptibility test by disc diffusion method. Sixty five out of 205 strains (31.7%) were Staphylococcus spp. and all of them were coagulase negative. Most of the strains belonged to S.epidermidis 49.23% (32/65) followed by S. saprophyticus 26.15% (17/65). Maximum isolates of S.epidermidis were from anterior nares 28.12% (9/32 strains of S.epidermidis). Highest number of methicillin resistant coagulase negative strains (3/9, 33.33%) were isolated from stethoscope of multidisciplinary cardiac unit ward followed by carriers in the anterior nares (2/9, 22.22%). Methicillin resistant coagulase negative staphylococci are prevalent in anterior nares of hospital personnel and in the hospital environment thereby providing a definite source for hospital acquired infection. All isolates were sensitive to vancomycin, ciprofloxacin and amikacin.

Microbial contamination on beef in relation to hygiene assessment based on criteria used in EU Decision 2001/471/EC

Thirty-six carcasses were sampled over a 12-month period at an Irish beef abattoir. Between one and five carcass sites (including the hock, brisket, cranial back, bung, inside round and outside round) were sampled after hind leg skinning, hide removal, bung tying, evisceration, splitting, washing, chilling for 24 h and boning, using a wet and dry, cotton wool swab technique. For each sample, total viable counts (TVC), Escherichia coli, total coliforms and Enterobacteriaceae were enumerated. The results are considered in relation to European Union Decision 2001/471/EC which sets performance criteria for TVCs and Enterobacteriaceae in samples taken by excision. Though not explicitly stated in the Decision, it has been proposed that microbiological performance criteria for samples taken by swabbing be set at 20% of the values set for excision samples. Therefore, log mean TVCs in carcass swab samples taken before chilling are acceptable, marginal and unacceptable when they are <2.8, 2.8–4.30 and >4.30 cm −2, respectively. By these criteria, TVCs on carcasses in the present study were in the marginal range. The marginal result for TVCs was due in the most part to hide removal operations, particularly at the hock and brisket sites. Bacterial contamination on post-chill carcasses was similar or lower to that on pre-chill carcasses, while boning resulted in general increases in TVCs and in E. coli, total coliform and Enterobacteriaceae numbers. In Decision 2001/471/EC, the effects of chilling and boning are not included in the assessment of process control. Data from this study indicate that performance criteria based on log mean Enterobacteriaceae values are unsuitable because of the infrequent occurrence of these organisms on the carcass.

Larvicidal effects of mineral turpentine, low aromatic white spirits, aqueous extracts of Cassia alata, and aqueous extracts, ethanolic extracts and essential oil of betel leaf (Piper betle) on Chrysomya megacephala.

Many methods have been employed, with variable success, in the treatment of cutaneous myiasis caused by Chrysomya species. Experiment 1: to assess the larvicidal effect of mineral turpentine (MT) and the main ingredient of MT, low aromatic white spirits (LAWS), on Chrysomya megacephala larvae in vitro. Experiment 2: to assess the larvicidal effects of aqueous extracts of winged senna (Cassia alata), and aqueous extracts, ethanolic extracts and essential oil of betel leaf (Piper betle). In experiment 1, two samples of LAWS were obtained from two industrialists (samples 1 and 2). Adult flies of C. megacephala were bred in the insectory of the Department of Parasitology, Faculty of Medicine, University of Colombo. Petri dishes were prepared with pads of cotton wool. These cotton pads were soaked separately in MT, LAWS samples 1 and 2, and normal saline as a control. Ten larvae were placed in each Petri dish. The activity of the larvae was observed and recorded half-hourly. MT and the two samples of LAWS were analyzed by chromatography. In experiment 2, volatile essential oil of betel was prepared using a standard steam distillation process. An ethanolic extract of betel was obtained after boiling the crushed leaf with water, and mixing the stock with ethanol. Betel oil dilutions of 1-4% were prepared using 1% Tween 80 (v/v aq) as a solvent, with 0.05 g/100 mL sodium lauryl sulphate (as stabilizer) and 0.01 g/100 mL methyl paraben (as a preservative). Cotton wool swabs soaked in 1, 2, 3 and 4% essential oil of betel in 1% Tween 80 (v/v aq) prepared as above, 1, 2, 3 and 4% ethanolic extract of betel, 50 and 25% aqueous extract of C. alata, and 50 and 25% aqueous extract of betel were placed in separate Petri dishes. Ten larvae were placed in each Petri dish. 1% Tween 80 solvent with the stabilizer and the preservative, but without betel essential oil, was used as a negative control and MT was used as a positive control. Larval motility was assessed as before. MT and the two LAWS samples killed the larvae in vitro within 4 h. Chromatography showed more unidentified constituents in MT than in pure LAWS, indicating additional substances in MT. The 4 and 3% preparations of the essential oil of betel were effective in killing 100% of the larvae of Chrysomya within 3 h 30 min. The 2% extract of betel essential oil killed 96.7% of larvae in 4 h. Ethanolic and aqueous extracts of betel, the aqueous extract of C. alata, normal saline and the Tween 80 solvent were not larvicidal. MT and LAWS, the main ingredient of MT, were effective in killing Chrysomya larvae. Essential oil obtained from betel leaves also showed a dose-dependent larvicidal effect on Chrysomya larvae. This natural product may be effective in the treatment of wound myiasis.

Noninvasive genotyping of dopamine receptor D4 (DRD4) using nanograms of DNA from substance-dependent patients.

A noninvasive DNA sampling method has been implemented collecting buccal mucosa cells by cotton wool swabs. An amount of 0.2 2 microg DNA per patient was obtained after the phenol-extraction procedure and 0.2 2 ng DNA template was sufficient for PCR amplification of the polymorphic 48 basepair repeat region of dopamine receptor D4 (DRD4) gene. PCR products were visualized during microfabricated electrophoretic separation by laser-induced fluorescent detection and automatic data registration. Initial data of genotyping drug-dependent subjects shows a relatively high ratio of heterozygotes, possessing either longer or shorter variants beside the common 4-repeat DRD4 allele.

Candida-associated denture stomatitis.

Candida-associated denture stomatitis was demonstrated by its cultivation in 171 out of 240 patients examined with partial or total dentures. After taking smears from lesions of the oral mucosa (tongue, cheeks, palate) and the contiguous denture surface by cotton wool swabs and inoculating them onto Sabouraud glucose agar and CHROMagar Candida, individual yeast species were identified by a germ tube, filamentous, and assimilation tests employing the commercial kit AuxaColor. Seven Candida species were identified in smears from the oral mucosa lesions and the contiguous denture surface: C. albicans (95 patients), C. tropicalis (26), C. parapsilosis (20), C. krusei (14), C. guilliermondii (12), C. lusitaniae (1) and C. freyschusii (1). Diabetes mellitus, neoplastic diseases, chemotherapy, radiotherapy, and broad-spectrum antibiotic therapy were identified as some of the large number of factors predisposing patients to stomatitis prothetica.