Analyze Diet

Topic:Biofilm

Biofilms are structured communities of microorganisms that adhere to surfaces and are embedded in a self-produced extracellular matrix. In horses, biofilms can form on various surfaces, including mucosal tissues and medical devices, and are associated with persistent infections and resistance to antimicrobial treatments. The presence of biofilms in equine health can complicate the management of bacterial infections, as they provide a protective environment for bacteria, making them less susceptible to antibiotics and immune system responses. This page compiles peer-reviewed research studies and scholarly articles that explore the formation, characteristics, and implications of biofilms in equine medicine, as well as strategies for their prevention and control.
In Vitro Efficacy of Nonantibiotic Treatments on Biofilm Disruption of Gram-Negative Pathogens and an In Vivo Model of Infectious Endometritis Utilizing Isolates from the Equine Uterus.
Journal of clinical microbiology    December 30, 2015   Volume 54, Issue 3 631-639 doi: 10.1128/JCM.02861-15
Ferris RA, McCue PM, Borlee GI, Loncar KD, Hennet ML, Borlee BR.In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CF...
Anti-biofilm activity of ultrashort cinnamic acid peptide derivatives against medical device-related pathogens.
Journal of peptide science : an official publication of the European Peptide Society    August 27, 2015   Volume 21, Issue 10 770-778 doi: 10.1002/psc.2805
Laverty G, McCloskey AP, Gorman SP, Gilmore BF.The threat of antimicrobial resistance has placed increasing emphasis on the development of innovative approaches to eradicate multidrug-resistant pathogens. Biofilm-forming microorganisms, for example, Staphylococcus epidermidis and Staphylococcus aureus, are responsible for increased incidence of biomaterial infection, extended hospital stays and patient morbidity and mortality. This paper highlights the potential of ultrashort tetra-peptide conjugated to hydrophobic cinnamic acid derivatives. These peptidomimetic molecules demonstrate selective and highly potent activity against resistant b...
Grazing livestock are exposed to terrestrial cyanobacteria.
Veterinary research    February 25, 2015   Volume 46 16 doi: 10.1186/s13567-015-0143-x
McGorum BC, Pirie RS, Glendinning L, McLachlan G, Metcalf JS, Banack SA, Cox PA, Codd GA.While toxins from aquatic cyanobacteria are a well-recognised cause of disease in birds and animals, exposure of grazing livestock to terrestrial cyanobacteria has not been described. This study identified terrestrial cyanobacteria, predominantly Phormidium spp., in the biofilm of plants from most livestock fields investigated. Lower numbers of other cyanobacteria, microalgae and fungi were present on many plants. Cyanobacterial 16S rDNA, predominantly from Phormidium spp., was detected in all samples tested, including 6 plant washings, 1 soil sample and ileal contents from 2 grazing horses. F...
Colostrum hexasaccharide, a novel Staphylococcus aureus quorum-sensing inhibitor.
Antimicrobial agents and chemotherapy    February 2, 2015   Volume 59, Issue 4 2169-2178 doi: 10.1128/AAC.03722-14
Srivastava A, Singh BN, Deepak D, Rawat AK, Singh BR.The discovery of quorum-sensing (QS) systems regulating antibiotic resistance and virulence factors (VFs) has afforded a novel opportunity to prevent bacterial pathogenicity. Dietary molecules have been demonstrated to attenuate QS circuits of bacteria. But, to our knowledge, no study exploring the potential of colostrum hexasaccharide (CHS) in regulating QS systems has been published. In this study, we analyzed CHS for inhibiting QS signaling in Staphylococcus aureus. We isolated and characterized CHS from mare colostrum by high-performance thin-layer chromatography (HPTLC), reverse-phase hig...
Differentiation Potential of Mesenchymal Stem Cells from Equine Bone Marrow Cultured on Hyaluronic Acid-Chitosan Polyelectrolyte Multilayer Biofilm.
Journal of stem cells    January 1, 2015   Volume 10, Issue 2 69-77 
Listoni AJ, Arruda I, Maia L, Barberini DJ, Martins I, Vasconcellos FC, Landim-Alvarenga FC.Nanotechnology techniques have a prominent role in the current technical and scientific scene. The layer-by-layer (LbL) deposition allows obtaining nanostructures with sophisticated multilayer, using a simple, but versatile technique. This procedure, which is used to coat and functionalize surfaces with nanometer- thick films, has applications in bioengineering, medicine, chemistry, materials and chemical engineering among other areas. Chitosan is a biomaterial, coming from the chitin, a very abundant polymer in nature, which has been recently tested as scaffolds. In this experiment we test th...
Candida tropicalis isolates obtained from veterinary sources show resistance to azoles and produce virulence factors.
Medical mycology    December 30, 2014   Volume 53, Issue 2 145-152 doi: 10.1093/mmy/myu081
Cordeiro Rde A, de Oliveira JS, Castelo-Branco Dde S, Teixeira CE, Marques FJ, Bittencourt PV, Carvalho VL, Bandeira Tde J, Brilhante RS, Moreira JL....Candida tropicalis has been associated with invasive candidiasis, being the first or second most common non-Candida albicans Candida species isolated in humans with candidemia and candiduria, as well as being frequently isolated from healthy animals. This study aimed to characterize C. tropicalis isolates (n = 64) obtained from several animal species regarding antifungal susceptibility and production of virulence factors. The isolates were obtained from the microbiota of healthy animals (goats, n = 25; sheep, n = 6; psittacines, n = 14; rheas, n = 6; horses, n = 2; sirenians, n = 5; shrimp, n ...
Upflow anaerobic solid-state (UASS) digestion of horse manure: Thermophilic vs. mesophilic performance.
Bioresource technology    October 18, 2014   Volume 175 8-16 doi: 10.1016/j.biortech.2014.10.041
Böske J, Wirth B, Garlipp F, Mumme J, Van den Weghe H.Energetic use of complex lignocellulosic wastes has gained global interest. Thermophilic digestion of horse manure based on straw was investigated using the upflow anaerobic solid-state (UASS) process. Increasing the organic loading rate from 2.5 to 5.5gvsL(-)(1)d(-)(1) enhanced the average methane production rate from 0.387 to 0.687LCH4L(-)(1)d(-)(1), whereas the yield decreased from 154.8 to 124.8LCH4kgvs(-)(1). A single-stage and two-stage process design showed almost the same performance. Compared to prior experiments at mesophilic conditions, thermophilic conditions showed a significantly...
Ultrashort cationic naphthalene-derived self-assembled peptides as antimicrobial nanomaterials.
Biomacromolecules    August 7, 2014   Volume 15, Issue 9 3429-3439 doi: 10.1021/bm500981y
Laverty G, McCloskey AP, Gilmore BF, Jones DS, Zhou J, Xu B.Self-assembling dipeptides conjugated to naphthalene show considerable promise as nanomaterial structures, biomaterials, and drug delivery devices. Biomaterial infections are responsible for high rates of patient mortality and morbidity. The presence of biofilm bacteria, which thrive on implant surfaces, are a huge burden on healthcare budgets, as they are highly resistant to current therapeutic strategies. Ultrashort cationic self-assembled peptides represent a highly innovative and cost-effective strategy to form antibacterial nanomaterials. Lysine conjugated variants display the greatest po...
Prevalence of biofilms on surgical suture segments in wounds of dogs, cats, and horses.
Veterinary pathology    July 3, 2014   Volume 52, Issue 2 295-297 doi: 10.1177/0300985814535609
König L, Klopfleisch R, Kershaw O, Gruber AD.The formation of biofilms on surgical implants is thought to play a major role in chronic infection and wound-healing disorders and has been rarely described in veterinary medicine. Due to poor and unreliable results from bacterial culturing, histology may be an economic tool for the detection of biofilms. In this study, the prevalence of biofilms on surgical suture materials and swabs with chronic wound-healing complications in dogs, cats, and horses was assessed by histologic examination using hematoxylin and eosin, Gram, and Giemsa stains, as well as periodic acid-Schiff reaction. Of the 91...
Anaerobic digestion of horse dung mixed with different bedding materials in an upflow solid-state (UASS) reactor at mesophilic conditions.
Bioresource technology    February 17, 2014   Volume 158 111-118 doi: 10.1016/j.biortech.2014.02.034
Böske J, Wirth B, Garlipp F, Mumme J, Van den Weghe H.Aim of this study was to investigate the use of upflow anaerobic solid-state (UASS) digestion for treating horse manure. Biochemical methane potential (BMP) tests conducted for varying mixtures of dung (hay and silage feed) and bedding material (wheat straw, flax, hemp, wood chips) showed that straw mixed with hay horse dung has the highest potential of [Formula: see text] . Continuous mesophilic digestion was conducted for 238 days using a single-stage UASS reactor (27 L) and a two-stage UASS system with an anaerobic filter (AF, 21 L). Increasing the organic loading rate (OLR) from 2.5 to 4.5...
The structure of latherin, a surfactant allergen protein from horse sweat and saliva.
Journal of the Royal Society, Interface    June 19, 2013   Volume 10, Issue 85 20130453 doi: 10.1098/rsif.2013.0453
Vance SJ, McDonald RE, Cooper A, Smith BO, Kennedy MW.Latherin is a highly surface-active allergen protein found in the sweat and saliva of horses and other equids. Its surfactant activity is intrinsic to the protein in its native form, and is manifest without associated lipids or glycosylation. Latherin probably functions as a wetting agent in evaporative cooling in horses, but it may also assist in mastication of fibrous food as well as inhibition of microbial biofilms. It is a member of the PLUNC family of proteins abundant in the oral cavity and saliva of mammals, one of which has also been shown to be a surfactant and capable of disrupting m...
Clostridium difficile PSI polysaccharide: synthesis of pentasaccharide repeating block, conjugation to exotoxin B subunit, and detection of natural anti-PSI IgG antibodies in horse serum.
Carbohydrate research    March 30, 2013   Volume 378 15-25 doi: 10.1016/j.carres.2013.03.018
Jiao Y, Ma Z, Hodgins D, Pequegnat B, Bertolo L, Arroyo L, Monteiro MA.Clostridium difficile is the most common cause of antimicrobial-associated diarrhea in humans and may cause death. Previously, we discovered that C. difficile expresses three polysaccharides, named PSI, PSII, and PSIII. It has now been established that PSII is a conserved antigen abundantly present on the cell-surface and biofilm of C. difficile. In contrast, the expression of PSI and PSIII appears to be stochastic processes. In this work, the total chemical synthesis of the PSI pentasaccharide repeating unit carrying a linker at the reducing end, α-l-Rhap-(1→3)-β-d-Glcp-(1→4)-[α-l-Rhap...
[Isolation, identification and enzyme characterization of a thermophilic cellulolytic anaerobic bacterium].
Wei sheng wu xue bao = Acta microbiologica Sinica    December 15, 2012   Volume 52, Issue 9 1160-1166 
Zhao Y, Ma S, Sun Y, Huang Y, Deng Y.To identify a thermophilic bacterium from horse manure to degrade cellulose efficiently, and to enrich microbial resources producing cellulolytic ethanol by co-culturing with thermophilic ethanol producing bacterium. Methods: We used Hungate anaerobic technique to isolate a strain named as HCp from horse manure mixed culture; its phylogeny was identified through 16S rDNA sequencing. Enzymatic assays were determined using DNS method. Results: The isolated HCp cells were straight with rods size of(0.35-0.50) microm x (2.42-6.40) microm, in the form of single or paring. This strain belongs to a s...
Latherin and other biocompatible surfactant proteins.
Biochemical Society transactions    July 27, 2011   Volume 39, Issue 4 1017-1022 doi: 10.1042/BST0391017
Kennedy MW.Horses and other equids are unusual in producing protein-rich sweat for thermoregulation, a major component of which is latherin, a highly surface-active, non-glycosylated protein that is a member of the PLUNC (palate, lung and nasal epithelium clone) family. Latherin produces a significant reduction in water surface tension at low concentrations (≤1 mg/ml), and probably acts as a wetting agent to facilitate evaporative cooling through a thick, waterproofed pelt. Latherin binds temporarily to hydrophobic surfaces, and so may also have a disruptive effect on microbial biofilms. It may conseq...
Solid-state anaerobic digestion of spent wheat straw from horse stall.
Bioresource technology    July 26, 2011   Volume 102, Issue 20 9432-9437 doi: 10.1016/j.biortech.2011.07.062
Cui Z, Shi J, Li Y.The spent wheat straw from horse stall bedding has lower cellulose and hemicellulose contents, but higher volatile fatty acid content than raw wheat straw. Biogas production from solid-state anaerobic digestion (SS-AD) of spent wheat straw and raw wheat straw was compared in this study. The SS-AD tests were conducted at 22% total solids (TS) content using inoculum from a liquid AD system at three feedstock-to-inoculum (F/I) ratios of 2.0, 4.0, and 6.0. Daily methane yields of spent wheat straw peaked 8 and 3 days earlier than those of raw wheat straw at F/I ratios of 2.0 and 4.0, respectively....
Microbiology of equine wounds and evidence of bacterial biofilms.
Veterinary microbiology    January 11, 2011   Volume 150, Issue 1-2 152-159 doi: 10.1016/j.vetmic.2011.01.003
Westgate SJ, Percival SL, Knottenbelt DC, Clegg PD, Cochrane CA.Horse wounds have a high risk of becoming infected due to their environment. Infected wounds harbour diverse populations of microorganisms, however in some cases these microorganisms can be difficult to identify and fail to respond to antibiotic treatment, resulting in chronic non-healing wounds. In human wounds this has been attributed to the ability of bacteria to survive in a biofilm phenotypic state. Biofilms are known to delay wound healing, principally due to their recalcitrance towards antimicrobial therapies and components of the innate immune response. This study describes the presenc...
Definite coordination arrangement of organometallic palladium complexes accumulated on the designed interior surface of apo-ferritin.
Chemical communications (Cambridge, England)    August 23, 2010   Volume 47, Issue 1 170-172 doi: 10.1039/c0cc02221g
Wang Z, Takezawa Y, Aoyagi H, Abe S, Hikage T, Watanabe Y, Kitagawa S, Ueno T.Apo-ferritin (apo-Fr) mutants are used as scaffolds to accommodate palladium (allyl) complexes. Various coordination arrangements of the Pd complexes are achieved by adjusting the positions of cysteine and histidine residues on the interior surface of the apo-Fr cage.
Advances in the diagnosis and treatment of chronic infectious and post-mating-induced endometritis in the mare.
Reproduction in domestic animals = Zuchthygiene    July 16, 2010   Volume 45 Suppl 2 21-27 doi: 10.1111/j.1439-0531.2010.01634.x
LeBlanc MM.Rapid physical uterine clearance is paramount for fertility. Mares that are unable to clear the by-products of insemination or foaling quickly may develop post-mating-induced or acute endometritis. If endometritis is not promptly resolved, the infection can become chronic. Endometritis can be difficult to identify because clinical signs, ultrasonographic and laboratory findings can vary between uterine pathogens. Some micro-organisms are associated with an influx of neutrophils and fluid into the uterine lumen while others are associated with only heavy debris on cytological specimens. Identif...
Chronic equine wounds: what is the role of infection and biofilms?.
Wounds : a compendium of clinical research and practice    June 1, 2010   Volume 22, Issue 6 138-145 
Westgate SJ, Percival SL, Knottenbelt DC, Clegg PD, Cochrane CA.Wound research is an evolving science in the equine species. In particular, interest is growing regarding the role that microorganisms play in delaying both acute and chronic wound healing. Equine wounds, particularly lower limb wounds, frequently display delayed healing and infection is commonly the underlying reason. This review will summarize the current research and knowledge surrounding equine wound healing and wound care. Particular focus is placed on the role that microbes play in chronic equine wounds and the significance of associated bacterial biofilms. .
Biofilm evidence and the microbial diversity of horse wounds.
Canadian journal of microbiology    March 20, 2009   Volume 55, Issue 2 197-202 doi: 10.1139/w08-115
Freeman K, Woods E, Welsby S, Percival SL, Cochrane CA.Evidence of biofilms in human chronic wounds are thought to be responsible for preventing healing in a timely manner. However, biofilm evidence in horse wounds has not yet been documented. Consequently, this study aimed to determine whether biofilms could be detected in wounds, and to investigate the microbiology of chronic wounds in horses. Prior to analysis, wound surfaces were irrigated with 5 mL of sterile saline to remove debris. All wounds were swabbed twice (1 cm2 area) using sterile cotton-tipped swabs. In addition to this, 2 tissue biopsies were taken to investigate evidence of biofil...
Glanders: off to the races with Burkholderia mallei.
FEMS microbiology letters    November 23, 2007   Volume 277, Issue 2 115-122 doi: 10.1111/j.1574-6968.2007.00949.x
Whitlock GC, Estes DM, Torres AG.Burkholderia mallei, the etiologic agent of the disease known as glanders, is primarily a disease affecting horses and is transmitted to humans by direct contact with infected animals. The use of B. mallei as a biological weapon has been reported and currently, there is no vaccine available for either humans or animals. Despite the history and highly infective nature of B. mallei, as well as its potential use as a bio-weapon, B. mallei research to understand the pathogenesis and the host responses to infection remains limited. Therefore, this minireview will focus on current efforts to elucida...
Purification of equine IgG using membrane based enhanced hybrid bioseparation technique: a potential method for manufacturing hyperimmune antibody.
Biotechnology and bioengineering    August 21, 2007   Volume 99, Issue 3 625-633 doi: 10.1002/bit.21614
Wang L, Sun X, Ghosh R.Hyperimmune equine IgG is widely used as antivenom and anti-rabies agents. This article discusses a membrane based enhanced hybrid bioseparation technique for efficient and scalable purification of equine immunoglobulin G (IgG) from horse serum. This technique is an improved version of a standard hybrid bioseparation technique developed within our group earlier for fractionation of human plasma proteins (Ghosh. 2004. J Membr Sci 237: 109-117). In the presence of a high antichaotropic salt concentration, equine IgG is selectively and reversibly captured within a stirred cell membrane module fro...
Vaginal lactic acid bacteria in the mare: evaluation of the probiotic potential of native Lactobacillus spp. and Enterococcus spp. strains.
Antonie van Leeuwenhoek    June 21, 2007   Volume 93, Issue 1-2 71-78 doi: 10.1007/s10482-007-9180-4
Fraga M, Perelmuter K, Delucchi L, Cidade E, Zunino P.Lactic acid bacteria (LAB) are important members of the human vaginal microbiota and their presence is considered beneficial. However, little is known about native vaginal bacteria in other animal species such as the horse. The aim of this work was to quantify the vaginal lactic acid bacteria and lactobacilli of mares and to establish if selected equine vaginal lactic acid bacteria, particularly Lactobacillus and Enterococcus spp. strains, could exhibit potential as probiotics. The vaginal lactic acid bacteria and lactobacilli of 26 mares were quantified by plate counts. Five strains (three La...
Biogas production with horse dung in solid-phase digestion systems.
Bioresource technology    March 26, 2007   Volume 99, Issue 5 1280-1292 doi: 10.1016/j.biortech.2007.02.008
Kusch S, Oechsner H, Jungbluth T.Experiments on methanogenesis from horse dung were conducted in laboratory-scale batch reactors in order to determine the substrate performance in a solid-phase digestion process, more specifically in terms of potential energy recovery and suitable process technology. Dung from a horse stable with straw bedding was used. The temperature was kept in the mesophilic range. In the percolation process (with process water sprinkled over the stacked biomass) a proportion of 10-20% of solid inoculum (pre-digested horse dung) was found to be suitable. Comparative experiments with both percolation and f...
Clinical efficacy of intravenous administration of marbofloxacin in a Staphylococcus aureus infection in tissue cages in ponies.
Journal of veterinary pharmacology and therapeutics    November 7, 2006   Volume 29, Issue 6 555-560 doi: 10.1111/j.1365-2885.2006.00803.x
Voermans M, van Soest JM, van Duijkeren E, Ensink JM.Tissue cages (TC), implanted subcutaneously in the neck in eight ponies, were inoculated with Staphylococcus aureus (S. aureus) to determine the clinical efficacy of marbofloxacin in the treatment of this infection. From 21 h after inoculation, marbofloxacin (6 mg/kg) was administered intravenously (i.v.) once daily for 7 days. Samples of the tissue cage fluid (TCF) were taken to determine marbofloxacin concentrations (days 1, 3 and 7), using high-pressure liquid chromatography, and numbers of viable bacteria [colony forming units (CFU)] (days 1, 3, 7, 14 and 21). Statistical analysis was used...
Osteomyelitis in horses.
The Veterinary clinics of North America. Equine practice    August 3, 2006   Volume 22, Issue 2 389-ix doi: 10.1016/j.cveq.2006.04.001
Goodrich LR.Much has been learned in the past decade about osteomyelitis. The inhibitory mechanisms of the "biofilm slime" layer that is formed by bacterial extracapsular exopolysaccharides and binds to bone, joints, and implants are now better understood than in the past. The surface colonization of bacteria that occurs within these biofilms is a biologic phenomenon that is somewhat unique to orthopedic infections. This survival strategy of bacteria is effective, and it is important for veterinarians who treat osteomyelitis to be aware of current diagnostic and therapeutic treatment modalities. The pract...
Miscibility of binary monolayers at the air-water interface and interaction of protein with immobilized monolayers by surface plasmon resonance technique.
Langmuir : the ACS journal of surfaces and colloids    June 28, 2006   Volume 22, Issue 14 6195-6202 doi: 10.1021/la0605642
Wang Y, Du X.The miscibility and stability of the binary monolayers of zwitterionic dipalmitoylphosphatidylcholine (DPPC) and cationic dioctadecyldimethylammonium bromide (DOMA) at the air-water interface and the interaction of ferritin with the immobilized monolayers have been studied in detail using surface pressure-area isotherms and surface plasmon resonance technique, respectively. The surface pressure-area isotherms indicated that the binary monolayers of DPPC and DOMA at the air-water interface were miscible and more stable than the monolayers of the two individual components. The surface plasmon re...
Effect of growth medium on hydrophobicity of Staphylococcus epidermidis.
The Indian journal of medical research    April 30, 2004   Volume 119, Issue 3 107-109 
Das SC, Kapoor KN.The present study was undertaken to evaluate the effect of growth medium on expression of hydrophobicity of Staphylococcus epidermidis. A total of 24 hydrophobic isolates of S. epidermidis, determined by n-hexadecane adherence assay (HAA) earlier were included. Five different growth media: horse blood agar (HBA), brain heart infusion agar (BHIA), brain heart infusion broth (BHIB), tryptic soy broth (TSB) and proteose peptone broth (PPB) were used. All 24 isolates exhibited the reproducible hydrophobicity when grown on HBA; however, 20 (83.33%), 19 (79.16%), 15 (62.50%) and 13 (54.16%) isolates...
Pathogenicity of Vibrio alginolyticus for cultured gilt-head sea bream (Sparus aurata L.).
Applied and environmental microbiology    October 31, 1998   Volume 64, Issue 11 4269-4275 doi: 10.1128/AEM.64.11.4269-4275.1998
Balebona MC, Andreu MJ, Bordas MA, Zorrilla I, Moriñigo MA, Borrego JJ.The in vivo and in vitro pathogenic activities of whole cells and extracellular products of Vibrio alginolyticus for cultured gilt-head sea bream were evaluated. The 50% lethal doses ranged from 5.4 x 10(4) to 1.0 x 10(6) CFU/g of body weight. The strains examined had the ability to adhere to skin, gill, and intestinal mucus of sea bream and to cultured cells of a chinook salmon embryo cell line. In addition, the in vitro ability of V. alginolyticus to adhere to mucus and skin cells of sea bream was demonstrated by scanning electron microscopy. The biological activities of extracellular produc...
Interaction of plasma gelsolin with tropomyosin.
FEBS letters    August 31, 1992   Volume 309, Issue 1 56-58 doi: 10.1016/0014-5793(92)80738-3
Koepf EK, Burtnick LD.Horse plasma gelsolin labelled with benzophenone-4-isothiocyanate can be photochemically cross-linked to rabbit cardiac tropomyosin. The cross-linking proceeds with greater efficiency in calcium-containing buffers. Further evidence for interaction between these proteins is provided by retention of fluorescently labelled gelsolin on tropomyosin-agarose affinity columns and by the ability of tropomyosin to cause an increase in the fluorescence intensity of gelsolin labelled with fluorescein-5-isothiocyanate. Both of these effects require the presence of calcium ions.