Displaying publications 1 - 20 of 72 in total

Abstract:
Sort:
  1. Abjani F, Khan NA, Yousuf FA, Siddiqui R
    Cont Lens Anterior Eye, 2016 Jun;39(3):239-43.
    PMID: 26675112 DOI: 10.1016/j.clae.2015.11.004
    Acanthamoeba cysts are highly resistant to contact lens disinfecting solutions. Acanthamoeba cyst wall is partially made of 1,4 β-glucan (i.e., cellulose) and other complex polysaccharides making it a hardy shell that protects the resident amoeba. Here, we hypothesize that targeting the cyst wall structure in addition to antiamoebic compound would improve the efficacy of marketed contact lens disinfecting solutions. Using chlorhexidine as an antiamoebic compound and cellulase enzyme to disrupt cyst wall structure, the findings revealed that combination of both agents abolished viability of Acanthamoeba castellanii cysts and trophozoites. When tested alone, none of the agents nor contact lens disinfecting solutions completely destroyed A. castellanii cysts and trophozoites. The absence of cyst wall-degrading enzymes in marketed contact lens disinfecting solutions render them ineffective against Acanthamoeba cysts. It is concluded that the addition of cyst wall degrading molecules in contact lens disinfecting solutions will enhance their efficacy in decreasing the incidence of Acanthamoeba effectively.
    Matched MeSH terms: Disinfection/methods
  2. Aizah N, Su Y, Shaifulnizam C, MRos M
    Malays Orthop J, 2014 Jul;8(2):66-8.
    PMID: 25279099 MyJurnal DOI: 10.5704/MOJ.1407.015
    Extruded bone is a rare complication of high energy open fractures, and there is only a handful of literature on reimplantation of the extruded segment. No clear guidelines exist regarding timing of reimplantation, stabilization of extruded bone segments, and also bone disinfection and sterilization techniques. Previous reports describe sterilization using thermal or chemical methods. We present a case of successful reimplantation of an extruded metaphyseal segment of femur after gamma sterilization in a fourteen- year old boy.
    Matched MeSH terms: Disinfection
  3. Ali A, Yeoh WK, Forney C, Siddiqui MW
    Crit Rev Food Sci Nutr, 2018;58(15):2632-2649.
    PMID: 29072844 DOI: 10.1080/10408398.2017.1339180
    Minimally processed fresh produce is one of the fastest growing segments of the food industry due to consumer demand for fresh, healthy, and convenient foods. However, mechanical operations of cutting and peeling induce the liberation of cellular contents at the site of wounding that can promote the growth of pathogenic and spoilage microorganisms. In addition, rates of tissue senescence can be enhanced resulting in reduced storage life of fresh-cut fruits and vegetables. Chlorine has been widely adopted in the disinfection and washing procedures of fresh-cut produce due to its low cost and efficacy against a broad spectrum of microorganisms. Continuous replenishment of chlorine in high organic wash water can promote the formation of carcinogenic compounds such as trihalomethanes, which threaten human and environmental health. Alternative green and innovative chemical and physical postharvest treatments such as ozone, electrolyzed water, hydrogen peroxide, ultraviolet radiation, high pressure processing, and ultrasound can achieve similar reduction of microorganisms as chlorine without the production of harmful compounds or compromising the quality of fresh-cut produce.
    Matched MeSH terms: Disinfection
  4. Arunachalam R, Rajeev V, Kumaresan R, Kurra SB
    J Contemp Dent Pract, 2019 Aug 01;20(8):952-956.
    PMID: 31797853
    INTRODUCTION: Assessment of host response to inflammation will throw light on the critical role of antioxidants (AOs) and free radicle damage in the etiology of periodontal disease. The purpose of the study was to assess the level of plasma oxidative stress in those having aggressive periodontal disease before and after full-mouth disinfection. Objectives were to find the influence of full-mouth disinfection analyzing the level of thiobarbituric acid reactive substances (TBARSs), thereby quantifying the lipid peroxidation (LPO) and also the activities of reduced glutathione (GSH), glutathione peroxidase (GPX), and catalase (CAT), valuing the AO defense systems in health and disease.

    MATERIALS AND METHODS: The valuation composed of 30 subjects with aggressive periodontal disease and 30 healthy controls. Clinical assessment included following periodontal parameters: plaque index (PI), papillary bleeding index (PBI), probing pocket depth (PPD), and clinical attachment level (CAL). Levels of bone loss were assessed by taking full-mouth periapical radiographs. Initial periodontal therapy comprises of full-mouth disinfection which includes subgingival scaling and root planing within 24 hours combined with adjunctive chlorhexidine chemotherapy for aggressive periodontitis subject's at sites indicated. The parameters (clinical) were evaluated at the baseline and 8 weeks after initial periodontal therapy at six sites of teeth indicated. Plasma samples were taken and evaluated by standard procedures as defined in the literature. All the values were weighed and related.

    RESULTS: Strong positive associations were detected among periodontal parameters and TBARS, enzymatic/nonenzymatic AO levels (p < 0.05), and pre- and postperiodontal management. The plasma levels of patients with aggressive periodontitis had high levels of TBARS and displayed a substantial escalation in the activities of GSH and GPX levels in the plasma matched to the healthy individuals (p < 0.05).

    CONCLUSION: This paper evaluated ROS activity and AO defense before and after treatment to stimulate added periodontal investigation in this part which will give an insight into the therapeutic options with foreseeable results.

    Matched MeSH terms: Disinfection
  5. Aws Hashim Ali Al-Kadhim, Azlan Jaafar, Mohd Nazrin Isa
    MyJurnal
    Nonsurgical retreatment involves removing mechanical barriers such as gutta-percha to achieve proper cleaning and disinfection. The complexity of the anatomy of molar tooth gives challenge in retreatment procedure. Thus, this study evaluates the amount of residual gutta-percha after retreatment with rotary files (Reciproc Blue®) from each maxillary first molar canal using cone-beam computed tomography (CBCT) and the time required to accomplish it. Nine freshly extracted maxillary molars were instrumented and obturated. Preoperative CBCT was taken, and retreatment was done using Reciproc Blue®. CBCT was taken post retreatment, and the residual volume percentage of gutta-percha from each canal was calculated. The total retreatment time was recorded, and the data were statistically analyzed. The result shows no statistically significant difference in the amount of residual filling material in mesiobuccal, distobuccal, and palatal canal for maxillary first molar and total time used for retreatment with Reciproc Blue® system.

    Matched MeSH terms: Disinfection
  6. Bidawid S, Malik N, Adegbunrin O, Sattar SA, Farber JM
    J Food Prot, 2004 Jan;67(1):103-9.
    PMID: 14717359
    While there is good epidemiological evidence for foods as vehicles for norovirus transmission, the precise means of spread and its control remain unknown. The feline calicivirus was used as a surrogate for noroviruses to study infectious virus transfer between hands and selected types of foods and environmental surfaces. Assessment of the potential of selected topicals in interrupting such virus transfer was also made. Ten microliters of inoculum of feline calicivirus deposited onto each fingerpad of adult subjects was allowed to air dry and the contaminated area on individual fingerpads was pressed (10 s at a pressure of 0.2 to 0.4 kg/cm2) onto 1-cm-diameter disks of ham, lettuce, or brushed stainless steel. The virus remaining on the donor and that transferred to the recipient surfaces was eluted and plaque assayed. Virus transfer to clean hands from experimentally contaminated disks of ham, lettuce, and stainless steel was also tested. Nearly 46 +/- 20.3, 18 +/- 5.7, and 13 +/- 3.6% of infectious virus was transferred from contaminated fingerpads to ham, lettuce, and metal disks, respectively. In contrast, approximately 6 +/- 1.8, 14 +/- 3.5, and 7 +/- 1.9% virus transfer occurred, respectively, from ham, lettuce, and metal disks to hands. One-way analysis of variance test showed that pretreatment (washing) of the fingerpads either with water or with both topical agent and water significantly (P < 0.05) reduced virus transfer to < or = 0.9%, as compared with < or = 2.3 and < or = 3.4% transfer following treatments with either 75% (vol/vol) ethanol or a commercial hand gel containing 62% ethanol, respectively. Despite wide variations in virus transfer among the targeted items used, intervention agents tested reduced virus transfer significantly (P < 0.05) when compared with that without such treatments (71 +/- 8.9%). These findings should help in a better assessment of the potential for cross-contamination of foods during handling and also assist in developing more effective approaches to foodborne spread of norovirus infections.
    Matched MeSH terms: Disinfection/methods; Hand Disinfection
  7. Bidawid S, Farber JM, Sattar SA
    Appl Environ Microbiol, 2000 Jul;66(7):2759-63.
    PMID: 10877765
    Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm(2) resulted in transfer of 9.2% +/- 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% +/- 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.
    Matched MeSH terms: Disinfection/methods; Hand Disinfection
  8. Boyle DK, Forsyth A, Bagg J, Stroubou K, Griffiths CE, Burke FJ
    J Dent, 2002 Jul-Aug;30(5-6):233-41.
    PMID: 12450714
    Glove wearing during patient treatment has been central to dental surgery infection control for over 15 years. However, little is known about the cutaneous effects of glove wearing on the hands of dental healthcare workers (DHCWs). The objective of this project was to assess the hand skin health of DHCWs before and after wearing gloves of two types and to compare this with a control group of non-DHCWs.
    Matched MeSH terms: Hand Disinfection
  9. Chan L, Yasmin AH, Ngeow YF, Ong GS
    Med J Malaysia, 1994 Mar;49(1):62-7.
    PMID: 8057993
    A closed enteral delivery system consisting of a cardboard tetrapack containing the sterile ready-to-use liquid feed and an independent sterile administration set, has been devised. We found bacterial contamination within 24 hours in this system in patients on ventilatory support in intensive care. This emphasises the need for meticulous care in handling enteral feeding systems to prevent environmental contamination.
    Matched MeSH terms: Hand Disinfection/methods
  10. Cheah WY, Show PL, Ng IS, Lin GY, Chiu CY, Chang YK
    Int J Biol Macromol, 2019 Apr 01;126:569-577.
    PMID: 30584947 DOI: 10.1016/j.ijbiomac.2018.12.193
    The electrospinning PAN nanofiber membrane (P-CN) was hydrolysed to convert carboxylic groups as reaction sites and covalently graft chitosan molecule. The chitosan derivatives with quaternary ammonium groups exerted greater efficiency against bacteria as compared to pure chitosan. Hence, the chitosan modified membrane (P-CS), can be functionalized with quaternary amine (i.e., glycidyl trimethyl ammonium chloride, GTMAC) to form quaternized chitosan nanofiber membrane (designated as P-HTCC) under various conditions (acidic, neutral, and alkaline). N-quaternized derivatives of chitosan modified membrane (N-HTCC) showed 72% and 60% degree of quaternization (DQ) under acidic and neutral conditions, respectively. Under alkaline condition, additional quaternization of N, O-HTCC via its amino and hydroxyl groups, has improved up to 90% DQ of the chitosan. The antibacterial activity of the quaternized chitosan modified membrane prepared from acetic acid medium is stronger than that prepared from water and alkaline media. Also, antibacterial activity of quaternized chitosan is stronger than chitosan modified membrane against E. coli. The microbiological assessments showed that the water-stable P-HTCC nanofiber membrane under modification in acidic medium exerted antibacterial activity up to 99.95% against E. coli. Therefore, the P-HTCC membrane exhibited high potential to be integrated into microfiltration membrane to effectively disinfect E. coli.
    Matched MeSH terms: Disinfection
  11. Chen WL, Ling YS, Lee DJH, Lin XQ, Chen ZY, Liao HT
    Chemosphere, 2020 Mar;242:125268.
    PMID: 31896175 DOI: 10.1016/j.chemosphere.2019.125268
    This study investigated chlorinated transformation products (TPs) and their parent micropollutants, aromatic pharmaceuticals and personal care products (PPCPs) in the urban water bodies of two metropolitan cities. Nine PPCPs and 16 TPs were quantitatively or semi-quantitatively determined using isotope dilution techniques and liquid chromatography-tandem mass spectrometry. TPs and most PPCPs were effectively removed by conventional wastewater treatments in a wastewater treatment plant (WWTP). Chlorinated parabens and all PPCPs (at concentrations below 1000 ng/L) were present in the waters receiving treated wastewater. By contrast, the waters receiving untreated wastewater contained higher levels of PPCPs (up to 9400 ng/L) and more species of chlorinated TPs including chlorinated parabens, triclosan, diclofenac, and bisphenol A. The very different chemical profiles between the water bodies of the two cities of similar geographical and climatic properties may be attributed to their respective uses of chemicals and policies of wastewater management. No apparent increase in the number of species or abundances of TPs was observed in either the chlorinated wastewater or the seawater rich in halogens. This is the first study to elucidate and compare the profiles of multiple TPs and their parent PPCPs in the water bodies of coastal cities from tropical islands. Our findings suggest that chlorinated derivatives of bisphenol A, diclofenac, triclosan, and parabens in the surface water originate from sources other than wastewater disinfection or marine chlorination. Although further studies are needed to identify the origins, conventional wastewater treatments may protect natural water bodies against contamination by those chlorinated substances.
    Matched MeSH terms: Disinfection/methods*
  12. Chew CC, Rajan P
    Malays J Med Sci, 2021 Feb;28(1):117-119.
    PMID: 33679228 DOI: 10.21315/mjms2021.28.1.15
    During the coronavirus disease 2019 (COVID-19) pandemic, the use of ultraviolet (UV) rays to disinfect skin areas, clothes and other objects at the entry/exit points of public spaces has been widely discussed by stakeholders. While ultraviolet germicidal irradiation (UVGI) has been shown to effectively inactivate coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV)-1 and Middle East respiratory syndrome coronavirus (MERS-CoV), no specific evidence proves that it effectively inactivates the new SARS-CoV-2 virus that causes COVID-19. Because UV rays damage human tissue, UVGI should be used with caution and not directly on human skin. Various guidelines recommend that UVGI should not be used as a sole agent for disinfecting surfaces or objects but as an adjunct to the latest standard disinfecting procedures.
    Matched MeSH terms: Disinfection
  13. Chook SW, Chia CH, Hatika Kaco, Sarani Zakaria, Huang NM, Neoh HM
    Sains Malaysiana, 2016;45:1663-1667.
    Incorporation of silver nanomaterial into polymer matrix can further accomplished their potential usage in real life
    applications. In our previous study, silver nanoparticles (AgNPs) and silver-graphene oxide nanocomposites (AgGO)
    were prepared via a rapid microwave-assisted method. Hereby, the as-synthesized AgNPs or AgGO was dispersed in a
    chitosan solution. Subsequently, the resultant mixture solution was further coagulated in a coagulation bath containing
    sodium hydroxide via a neutralization process. This resulted in the formation of spherical-shaped chitosan beads.
    The structure of the beads showed that the chitosan beads embedded with AgGO exhibited a more porous structure as
    compared to the plain chitosan beads. Furthermore, the chitosan beads containing AgNPs or AgGO were tested for
    their antibacterial activity against Escherichia coli and Staphylococcus aureus. The antibacterial results indicated that
    the silver nanomaterial contained chitosan beads could effectively inhibit the growth of both E. coli and S. aureus as
    compared to the bare chitosan beads. The produced chitosan nanocomposite envisioned that can be potentially employed
    for water disinfection purpose.
    Matched MeSH terms: Disinfection
  14. Chum JD, Lim DJZ, Sheriff SO, Pulikkotil SJ, Suresh A, Davamani F
    Restor Dent Endod, 2019 Feb;44(1):e8.
    PMID: 30834230 DOI: 10.5395/rde.2019.44.e8
    Objectives: Irrigants are imperative in endodontic therapy for the elimination of pathogens from the infected root canal. The present study compared the antimicrobial efficacy of octenidine dihydrochloride (OCT) with chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against Staphylococcus epidermidis (S. epidermidis) for root canal disinfection.

    Materials and Methods: The minimum inhibitory concentration (MIC) was obtained using serial dilution method. The agar diffusion method was then used to determine the zones of inhibition for each irrigant. Lastly, forty 6-mm dentin blocks were prepared from human mandibular premolars and inoculated with S. epidermidis. Samples were randomly divided into 4 groups of 10 blocks and irrigated for 3 minutes with saline (control), 2% CHX, 3% NaOCl, or 0.1% OCT. Dentin samples were then collected immediately for microbial analysis, including an analysis of colony-forming units (CFUs).

    Results: The MICs of each tested irrigant were 0.05% for CHX, 0.25% for NaOCl, and 0.0125% for OCT. All tested irrigants showed concentration-dependent increase in zones of inhibition, and 3% NaOCl showed the largest zone of inhibition amongst all tested irrigants (p < 0.05). There were no significant differences among the CFU measurements of 2% CHX, 3% NaOCl, and 0.1% OCT showing complete elimination of S. epidermidis in all samples.

    Conclusions: This study showed that OCT was comparable to or even more effective than CHX and NaOCl, demonstrating antimicrobial activity at low concentrations against S. epidermidis.

    Matched MeSH terms: Disinfection
  15. Das A, Barua A, Mohimin MA, Abedin J, Khandaker MU, Al-Mugren KS
    Healthcare (Basel), 2021 Apr 10;9(4).
    PMID: 33920290 DOI: 10.3390/healthcare9040445
    BACKGROUND: The use of a touchless automated hand sanitizer dispenser may play a key role to reduce contagious diseases. The key problem of the conventional ultrasonic and infra-red-based dispensers is their malfunctioning due to the interference of sunlight, vehicle sound, etc. when deployed in busy public places. To overcome such limitations, this study introduced a laser-based sensing device to dispense sanitizer in an automated touchless process.

    METHOD: The dispensing system is based on an Arduino circuit breadboard where an ATmega328p microcontroller was pre-installed. To sense the proximity, a light-dependent resistor (LDR) is used where the laser light is to be blocked after the placement of human hands, hence produced a sharp decrease in the LDR sensor value. Once the LDR sensor value exceeds the lower threshold, the pump is actuated by the microcontroller, and the sanitizer dispenses through the nozzle.

    RESULTS AND DISCUSSION: A novel design and subsequent fabrication of a low-cost, touchless, automated sanitizer dispenser to be used in public places, was demonstrated. The overall performance of the manufactured device was analyzed based on the cost and power consumption, and environmental factors by deploying it in busy public places as well as in indoor environment in major cities in Bangladesh, and found to be more efficient and cost-effective compared to other dispensers available in the market. A comprehensive discussion on this unique design compared to the conventional ultrasonic and infra-red based dispensers, is presented to show its suitability over the commercial ones. The guidelines of the World Health Organization are followed for the preparation of sanitizer liquid. A clear demonstration of the circuitry connections is presented herein, which facilitates the interested individual to manufacture a cost-effective dispenser device in a relatively short time and use it accordingly. Conclusion: This study reveals that the LDR-based automated hand sanitizer dispenser system is a novel concept, and it is cost-effective compared to the conventional ones. The presented device is expected to play a key role in contactless hand disinfection in public places, and reduce the spread of infectious diseases in society.

    Matched MeSH terms: Hand Disinfection
  16. FARAH EILYANA MOHAMED
    MyJurnal
    Solar photocatalysis is a green technology that takes advantage of sustainable solar energy for enhancing oxidation process of numerous harmful water contaminants. In this study, a custom solar driven zinc oxide (ZnO)-mediated photocatalytic system was developed and its efficiency to remove organic contaminants as well as to disinfect selected bacteria was investigated. Methylene blue (MB) dye was used as the model organic contaminant, while Escherichia coli(E.coli) was used as the model fecal coliform bacteria in contaminated water. A series of photodegradation experiments were conducted on water contaminated with either 10 mg/L of MB or ~1010CFU/ml of E.coli. The experiments were completed under sunlight irradiation in the presence of 1 g/L of nano ZnO photocatalyst for up to 6 hours. Using a solar thermal collector, the photoreactor operated in the temperature range of 25 to 50 oC. The findings revealed that the combination of solar thermal with solar photocatalysis usingZnO intensified the degradation of MB and disinfection of E.coli. 98.08% of MB dye and 99.99% of E.coliwere successfully removed from the water within the first 3 hours of treatment. Almost complete removal was eventually achieved after 6 hours of treatment. It is therefore suggested that ZnO-based solar photocatalytic system developed in this study is highly efficient at enhancing water decontamination process.
    Matched MeSH terms: Disinfection
  17. Faizah, J., Vanitha, S.
    MyJurnal
    Introduction : The focus of this paper is to evaluate effectiveness of health education material produced and identify effective educational methods in disseminating health-related information. The study explores the knowledge, attitude and practice level among flood victims in Sub-District Sri Medan, Batu Pahat.
    Methodology : Convenient sampling method was adopted as a technique to get 195 respondents aged 18 years and above who had stayed in flood relief centres in the district. A set of questionnaire designed to collect data on demography, effectiveness of health education material, accessibility to education materials, preferable educational methods during flood situation, and flood victims knowledge, attitude and practices.
    Result : The study found no association between knowledge level and practice of seven steps hand washing. Result showed poster was regarded as most preferable method in disseminating health related information during flood. No association was found in demographic determinants and knowledge. The length of stay in relief centre has significant association with the level of knowledge obtained.
    Conclusion : The use of qualitative and quantitative methods together able to determine accurately the effectiveness of the health education materials used during the disaster as well as the impact in behavioral change.
    Matched MeSH terms: Hand Disinfection
  18. Far HS, Pin NT, Kong CY, Fong KS, Kian CW, Yan CK
    Int Arch Occup Environ Health, 1993;64(6):439-43.
    PMID: 8458660
    The present study was conducted to evaluate the role of ingestion through hand and mouth contamination in the absorption of lead in 25 lead-acid battery workers. Levels of personal exposure to airborne lead ranged from 0.004 to 2.58 mg/m3 [geometric mean 0.098, with 25% of samples exceeding threshold limit values (ACGIH) of 0.15 mg/m3]; the mean (SD) blood lead level was 48.9 (10.8) micrograms/dl. Mean hand lead contents increased 33-fold from preshift levels on Monday mornings (33.5 micrograms/500 ml) to midshift levels on Thursday afternoons (1121 micrograms/500 ml). Mouth lead contents increased 16-fold from 0.021 micrograms/50 ml on Mondays to 0.345 micrograms/50 ml on Thursdays. The typical Malay racial habit of feeding with bare hands and fingers without utensils (closely associated with mouth and hand lead levels on Mondays) explained the bulk of the variance in blood lead levels (40%), with mouth lead on Thursdays (closely associated with poor personal hygiene) explaining a further 10%. Air lead was not a significant explanatory variable. The implementation of a programme of reinforcing hand-washing and mouth-rinsing practices resulted in a reduction of the blood lead level by 11.5% 6 months later. These results indicate that parenteral intake from hand and mouth contamination is an important cause of lead absorption in lead-exposed workers.
    Matched MeSH terms: Hand Disinfection*
  19. Fernando WJ, Othman R
    Math Biosci, 2006 Feb;199(2):175-87.
    PMID: 16387333
    Disinfectants are generally used to inactivate microorganisms in solutions. The process of inactivation involves the disinfectant in the liquid diffusing towards the bacteria sites and thereafter reacting with bacteria at rates determined by the respective reaction rates. Such processes have demonstrated an initial lag phase followed by an active depletion phase of bacteria. This paper attempts to study the importance of the combined effects of diffusion of the disinfectant through the outer membrane of the bacteria and transport through the associated concentration boundary layers (CBLs) during the initial lag phase. Mathematical equations are developed correlating the initial concentration of the disinfectant with time required for reaching a critical concentration (C*) at the inner side of the membrane of the cell based on diffusion of disinfectant through the outer membranes of the bacteria and the formation of concentration boundary layers on both sides of the membranes. Experimental data of the lag phases of inactivation already available in the literature for inactivation of Bacillus subtilis spores with ozone and monochloramine are tested with the equations. The results seem to be in good agreement with the theoretical equations indicating the importance of diffusion process across the outer cell membranes and the resulting CBL's during the lag phase of disinfection.
    Matched MeSH terms: Disinfection/methods
  20. Goh CS
    Family Practitioner, 1986;9:40-42.
    The plasma cholinesterase baseline levels in Malaysian workers are within the guidelines used. There is a need to carry out close monitoring of workers handling organophosphate s even in a well-run, modern factory where there are no hazards in the plant operation. Abnormal results are mainly because many of our workers are unaware of the health hazards and do not follow orders properly, ie personal hygiene, such as washing of hands before eating, etc. The use of temporary workers should be discouraged because of poor compliance with rules and difficulty in follow up. Product stewardship and education of farmers, sprayers and end users are of paramount importance. Finally there is a great need for educaiton of everyone from factory workers, farmers, sprayers to the general public.
    Matched MeSH terms: Hand Disinfection
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links