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1.
Med J Aust ; 220(11): 582-591, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38763516

ABSTRACT

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) affect up to 10% of all pregnancies annually and are associated with an increased risk of maternal and fetal morbidity and mortality. This guideline represents an update of the Society of Obstetric Medicine of Australia and New Zealand (SOMANZ) guidelines for the management of hypertensive disorders of pregnancy 2014 and has been approved by the National Health and Medical Research Council (NHMRC) under section 14A of the National Health and Medical Research Council Act 1992. In approving the guideline recommendations, NHMRC considers that the guideline meets NHMRC's standard for clinical practice guidelines. MAIN RECOMMENDATIONS: A total of 39 recommendations on screening, preventing, diagnosing and managing HDP, especially preeclampsia, are presented in this guideline. Recommendations are presented as either evidence-based recommendations or practice points. Evidence-based recommendations are presented with the strength of recommendation and quality of evidence. Practice points were generated where there was inadequate evidence to develop specific recommendations and are based on the expertise of the working group. CHANGES IN MANAGEMENT RESULTING FROM THE GUIDELINE: This version of the SOMANZ guideline was developed in an academically robust and rigorous manner and includes recommendations on the use of combined first trimester screening to identify women at risk of developing preeclampsia, 14 pharmacological and two non-pharmacological preventive interventions, clinical use of angiogenic biomarkers and the long term care of women who experience HDP. The guideline also includes six multilingual patient infographics which can be accessed through the main website of the guideline. All measures were taken to ensure that this guideline is applicable and relevant to clinicians and multicultural women in regional and metropolitan settings in Australia and New Zealand.


Subject(s)
Hypertension, Pregnancy-Induced , Humans , Pregnancy , Female , Australia , New Zealand , Hypertension, Pregnancy-Induced/diagnosis , Hypertension, Pregnancy-Induced/therapy , Hypertension, Pregnancy-Induced/prevention & control , Pre-Eclampsia/diagnosis , Pre-Eclampsia/prevention & control , Pre-Eclampsia/therapy , Societies, Medical , Obstetrics/standards , Antihypertensive Agents/therapeutic use , Practice Guidelines as Topic
2.
Commun Biol ; 6(1): 734, 2023 07 15.
Article in English | MEDLINE | ID: mdl-37454193

ABSTRACT

Breeding females can cooperate by rearing their offspring communally, sharing synergistic benefits of offspring care but risking exploitation by partners. In lactating mammals, communal rearing occurs mostly among close relatives. Inclusive fitness theory predicts enhanced cooperation between related partners and greater willingness to compensate for any partner under-investment, while females are less likely to bias investment towards own offspring. We use a dual isotopic tracer approach to track individual milk allocation when familiar pairs of sisters or unrelated house mice reared offspring communally. Closely related pairs show lower energy demand and pups experience better access to non-maternal milk. Lactational investment is more skewed between sister partners but females pay greater energetic costs per own offspring reared with an unrelated partner. The choice of close kin as cooperative partners is strongly favoured by these direct as well as indirect benefits, providing a driver to maintain female kin groups for communal breeding.


Subject(s)
Lactation , Milk , Female , Animals , Mice , Mammals
3.
Proc Natl Acad Sci U S A ; 120(25): e2300794120, 2023 06 20.
Article in English | MEDLINE | ID: mdl-37307448

ABSTRACT

Chemical communication by females remains poorly understood, with most attention focused on female advertisement of sexual receptivity to males or mother-offspring communication. However, in social species, scents are likely to be important for mediating competition and cooperation between females determining individual reproductive success. Here, we explore chemical signaling by female laboratory rats (Rattus norvegicus) to test i) whether females target their deployment of scent information differentially according to their sexual receptivity and the genetic identity of both female and male conspecifics signaling in the local environment and ii) whether females are attracted to gain the same or different information from female scents compared to males. Consistent with targeting of scent information to colony members of similar genetic background, female rats increased scent marking in response to scents from females of the same strain. Females also suppressed scent marking in response to male scent from a genetically foreign strain while sexually receptive. Proteomic analysis of female scent deposits revealed a complex protein profile, contributed from several sources but dominated by clitoral gland secretion. In particular, female scent marks contained a series of clitoral-derived hydrolases and proteolytically truncated major urinary proteins (MUPs). Manipulated blends of clitoral secretion and urine from estrus females were strongly attractive to both sexes, while voided urine alone stimulated no interest. Our study reveals that information about female receptive status is shared between females as well as with males, while clitoral secretions containing a complex set of truncated MUPs and other proteins play a key role in female communication.


Subject(s)
Body Fluids , Odorants , Female , Male , Animals , Rats , Proteomics , Genetic Background , Hydrolases , Pheromones
4.
Am Nat ; 201(2): 256-268, 2023 02.
Article in English | MEDLINE | ID: mdl-36724459

ABSTRACT

AbstractFemale reproductive success is often limited by access to resources, and this can lead to social competition both within and between kin groups. Theory predicts that both resource availability and relatedness should influence the fitness consequences of social competition. However, testing key predictions requires differentiating the effects of these two factors. Here, we achieve this experimentally by manipulating the social environment of house mice, a facultative communal breeding species with known kin discrimination ability. This allows us to investigate (1) the reproductive costs of defending a limited resource in response to cues of social competition and (2) whether such costs, or their potential mitigation via cooperative behavior, are influenced by the relatedness of competitors. Our results support the hypothesis that resource defense can be costly for females, potentially trading off against maternal investment. When the availability of protected nest sites was limited, subjects (1) were more active, (2) responded more strongly to simulated territory intrusions via competitive signaling, and (3) produced smaller weaned offspring. However, we found no evidence that the propensity for kin to cooperate was influenced by the relatedness of rivals. Communal breeding between sisters occurred independently of the relatedness of competitors and communally breeding sisters weaned fewer offspring when competing with unrelated females, despite our study being designed to prevent infanticide between kin groups. Our findings thus demonstrate that female competition has fitness costs and that associating with kin is beneficial to avoid negative fitness consequences of competing with nonkin, in addition to more widely recognized kin-selected benefits.


Subject(s)
Cooperative Behavior , Social Behavior , Animals , Mice , Female , Humans , Social Environment , Siblings , Reproduction
5.
Viruses ; 13(6)2021 06 21.
Article in English | MEDLINE | ID: mdl-34205512

ABSTRACT

Mature male mice produce a particularly high concentration of major urinary proteins (MUPs) in their scent marks that provide identity and status information to conspecifics. Darcin (MUP20) is inherently attractive to females and, by inducing rapid associative learning, leads to specific attraction to the individual male's odour and location. Other polymorphic central MUPs, produced at much higher abundance, bind volatile ligands that are slowly released from a male's scent marks, forming the male's individual odour that females learn. Here, we show that infection of C57BL/6 males with LCMV WE variants (v2.2 or v54) alters MUP expression according to a male's infection status and ability to clear the virus. MUP output is substantially reduced during acute adult infection with LCMV WE v2.2 and when males are persistently infected with LCMV WE v2.2 or v54. Infection differentially alters expression of darcin and, particularly, suppresses expression of a male's central MUP signature. However, following clearance of acute v2.2 infection through a robust virus-specific CD8 cytotoxic T cell response that leads to immunity to the virus, males regain their normal mature male MUP pattern and exhibit enhanced MUP output by 30 days post-infection relative to uninfected controls. We discuss the likely impact of these changes in male MUP signals on female attraction and mate selection. As LCMV infection during pregnancy can substantially reduce embryo survival and lead to lifelong infection in surviving offspring, we speculate that females use LCMV-induced changes in MUP expression both to avoid direct infection from a male and to select mates able to develop immunity to local variants that will be inherited by their offspring.


Subject(s)
Lymphocytic Choriomeningitis/complications , Lymphocytic choriomeningitis virus/pathogenicity , Proteins/metabolism , Animals , Female , Intercellular Signaling Peptides and Proteins/genetics , Lymphocytic Choriomeningitis/immunology , Lymphocytic choriomeningitis virus/immunology , Male , Mice , Mice, Inbred C57BL , Odorants , Pheromones/metabolism , Proteins/analysis , Proteins/genetics
6.
Proc Natl Acad Sci U S A ; 117(44): 27465-27473, 2020 11 03.
Article in English | MEDLINE | ID: mdl-33077605

ABSTRACT

Mating plugs are produced by many sexually reproducing animals and are hypothesized to promote male fertilization success under promiscuous mating. However, tests of this hypothesis have been constrained by an inability to discriminate ejaculates of different males in direct competition. Here, we use stable isotope labeling in vivo and proteomics to achieve this in a promiscuous rodent, Myodes glareolus We show that, although the first male's plug is usually dislodged, it can be retained throughout the second male's copulation. Retained plugs did not completely block rival sperm but did significantly limit their numbers. Differences in the number of each male's sperm progressing through the female reproductive tract were also explained by natural variation in the size of mating plugs and reproductive accessory glands from which major plug proteins originate. Relative sperm numbers in turn predicted the relative fertilization success of rival males. Our application of stable isotopes to label ejaculates resolves a longstanding debate by revealing how rodent mating plugs promote fertilization success under competitive conditions. This approach opens new opportunities to reveal cryptic mechanisms of postcopulatory sexual selection among diverse animal taxa.


Subject(s)
Arvicolinae/physiology , Copulation/physiology , Seminal Plasma Proteins/metabolism , Sexual Selection/physiology , Sperm Transport/physiology , Animals , Female , Male , Mating Preference, Animal , Proteomics , Seminal Vesicles/metabolism , Sperm Count , Sperm Motility
7.
BMC Biol ; 16(1): 48, 2018 04 27.
Article in English | MEDLINE | ID: mdl-29703213

ABSTRACT

BACKGROUND: Reliable recognition of individuals requires phenotypic identity signatures that are both individually distinctive and appropriately stable over time. Individual-specific vocalisations or visual patterning are well documented among birds and some mammals, whilst odours play a key role in social recognition across many vertebrates and invertebrates. Less well understood, though, is whether individuals are recognised through variation in cues that arise incidentally from a wide variety of genetic and non-genetic differences between individuals, or whether animals evolve distinctive polymorphic signals to advertise identity reliably. As a bioassay to understand the derivation of individual-specific odour signatures, we use female attraction to the individual odours of male house mice (Mus musculus domesticus), learned on contact with a male's scent marks. RESULTS: Learned volatile odour signatures are determined predominantly by individual differences in involatile major urinary protein (MUP) signatures, a specialised set of communication proteins that mice secrete in their urine. Recognition of odour signatures in genetically distinct mice depended on differences in individual MUP genotype. Direct manipulation using recombinant MUPs confirmed predictable changes in volatile signature recognition according to the degree of matching between MUP profiles and the learned urine template. Both the relative amount of the male-specific MUP pheromone darcin, which induces odour learning, and other MUP isoforms influenced learned odour signatures. By contrast, odour recognition was not significantly influenced by individual major histocompatibility complex genotype. MUP profiles shape volatile odour signatures through isoform-specific differences in binding and release of urinary volatiles from scent deposits, such that volatile signatures were recognised from the urinary protein fraction alone. Manipulation using recombinant MUPs led to quantitative changes in the release of known MUP ligands from scent deposits, with MUP-specific and volatile-specific effects. CONCLUSIONS: Despite assumptions that many genes contribute to odours that can be used to recognise individuals, mice have evolved a polymorphic combinatorial MUP signature that shapes distinctive volatile signatures in their scent. Such specific signals may be more prevalent within complex body odours than previously realised, contributing to the evolution of phenotypic diversity within species. However, differences in selection may also result in species-specific constraints on the ability to recognise individuals through complex body scents.


Subject(s)
Odorants , Proteins/metabolism , Animals , Female , Intercellular Signaling Peptides and Proteins , Male , Mice , Pheromones/metabolism , Proteins/genetics , Smell
8.
Sci Rep ; 7: 44992, 2017 03 24.
Article in English | MEDLINE | ID: mdl-28337988

ABSTRACT

When hybridisation carries a cost, natural selection is predicted to favour evolution of traits that allow assortative mating (reinforcement). Incipient speciation between the two European house mouse subspecies, Mus musculus domesticus and M.m.musculus, sharing a hybrid zone, provides an opportunity to understand evolution of assortative mating at a molecular level. Mouse urine odours allow subspecific mate discrimination, with assortative preferences evident in the hybrid zone but not in allopatry. Here we assess the potential of MUPs (major urinary proteins) as candidates for signal divergence by comparing MUP expression in urine samples from the Danish hybrid zone border (contact) and from allopatric populations. Mass spectrometric characterisation identified novel MUPs in both subspecies involving mostly new combinations of amino acid changes previously observed in M.m.domesticus. The subspecies expressed distinct MUP signatures, with most MUPs expressed by only one subspecies. Expression of at least eight MUPs showed significant subspecies divergence both in allopatry and contact zone. Another seven MUPs showed divergence in expression between the subspecies only in the contact zone, consistent with divergence by reinforcement. These proteins are candidates for the semiochemical barrier to hybridisation, providing an opportunity to characterise the nature and evolution of a putative species recognition signal.


Subject(s)
Genetic Heterogeneity , Genetic Variation , Proteins/genetics , Animals , Europe , Evolution, Molecular , Female , Geography , Male , Mice , Proteins/metabolism , Proteome , Proteomics/methods , Selection, Genetic , Species Specificity
9.
Sci Rep ; 7: 42940, 2017 02 22.
Article in English | MEDLINE | ID: mdl-28225021

ABSTRACT

Mouse lemurs are basal primates that rely on chemo- and acoustic signalling for social interactions in their dispersed social systems. We examined the urinary protein content of two mouse lemurs species, within and outside the breeding season, to assess candidates used in species discrimination, reproductive or competitive communication. Urine from Microcebus murinus and Microcebus lehilahytsara contain a predominant 10 kDa protein, expressed in both species by some, but not all, males during the breeding season, but at very low levels by females. Mass spectrometry of the intact proteins confirmed the protein mass and revealed a 30 Da mass difference between proteins from the two species. Tandem mass spectrometry after digestion with three proteases and sequencing de novo defined the complete protein sequence and located an Ala/Thr difference between the two species that explained the 30 Da mass difference. The protein (mature form: 87 amino acids) is an atypical member of the whey acidic protein family (WFDC12). Seasonal excretion of this protein, species difference and male-specific expression during the breeding season suggest that it may have a function in intra- and/or intersexual chemical signalling in the context of reproduction, and could be a cue for sexual selection and species recognition.


Subject(s)
Cheirogaleidae/physiology , Milk Proteins/urine , Animal Communication , Animals , Breeding , Chromatography, High Pressure Liquid , Female , Male , Milk Proteins/analysis , Milk Proteins/metabolism , Seasons , Tandem Mass Spectrometry
10.
Curr Biol ; 25(20): 2631-41, 2015 Oct 19.
Article in English | MEDLINE | ID: mdl-26412134

ABSTRACT

Cooperation between relatives yields important fitness benefits, but genetic loci that allow recognition of unfamiliar kin have proven elusive. Sharing of kinship markers must correlate strongly with genome-wide similarity, creating a special challenge to identify specific loci used independently of other shared loci. Two highly polymorphic gene complexes, detected through scent, have been implicated in vertebrates: the major histocompatibility complex (MHC), which could be vertebrate wide, and the major urinary protein (MUP) cluster, which is species specific. Here we use a new approach to independently manipulate sharing of putative genetic kin recognition markers, with the animal itself or known family members, while genome-wide relatedness is controlled. This was applied to wild-stock outbred female house mice, which nest socially and often rear offspring cooperatively with preferred nest partners. Females preferred to nest with sisters, regardless of prior familiarity, confirming the use of phenotype matching. Among unfamiliar relatives, females strongly preferred nest partners that shared their own MUP genotype, though not those with only a partial (single-haplotype) MUP match to themselves or known family. In the absence of MUP sharing, females preferred related partners that shared multiple loci across the genome to unrelated females. However, MHC sharing was not used, even when MHC type completely matched their own or that of known relatives. Our study provides empirical evidence that highly polymorphic species-specific kinship markers can evolve where reliable recognition of close relatives is an advantage. This highlights the potential for identifying other genetic kinship markers in cooperative species and calls for better evidence that MHC can play this role.


Subject(s)
Major Histocompatibility Complex , Mice/physiology , Proteins/genetics , Recognition, Psychology , Animals , Female , Genetic Markers/genetics , Genotype , Mice/genetics , Phenotype , Proteins/metabolism , Reproduction
11.
Science ; 338(6113): 1462-5, 2012 Dec 14.
Article in English | MEDLINE | ID: mdl-23239735

ABSTRACT

Many mammals use scent marking for sexual and competitive advertisement, but little is known about the mechanism by which scents are used to locate mates and competitors. We show that darcin, an involatile protein sex pheromone in male mouse urine, can rapidly condition preference for its remembered location among females and competitor males so that animals prefer to spend time in the site even when scent is absent. Learned spatial preference is conditioned through contact with darcin in a single trial and remembered for approximately 14 days. This pheromone-induced learning allows animals to relocate sites of particular social relevance and provides proof that pheromones such as darcin can be highly potent stimuli for social learning.


Subject(s)
Competitive Behavior/physiology , Maze Learning/physiology , Proteins/physiology , Sex Attractants/physiology , Spatial Behavior/physiology , Animals , Competitive Behavior/drug effects , Conditioning, Psychological/drug effects , Conditioning, Psychological/physiology , Female , Intercellular Signaling Peptides and Proteins , Male , Maze Learning/drug effects , Mice , Mice, Inbred C57BL , Proteins/pharmacology , Sex Attractants/pharmacology , Sex Attractants/urine , Smell/drug effects , Smell/physiology , Spatial Behavior/drug effects
12.
BMC Biol ; 8: 75, 2010 Jun 03.
Article in English | MEDLINE | ID: mdl-20525243

ABSTRACT

BACKGROUND: Among invertebrates, specific pheromones elicit inherent (fixed) behavioural responses to coordinate social behaviours such as sexual recognition and attraction. By contrast, the much more complex social odours of mammals provide a broad range of information about the individual owner and stimulate individual-specific responses that are modulated by learning. How do mammals use such odours to coordinate important social interactions such as sexual attraction while allowing for individual-specific choice? We hypothesized that male mouse urine contains a specific pheromonal component that invokes inherent sexual attraction to the scent and which also stimulates female memory and conditions sexual attraction to the airborne odours of an individual scent owner associated with this pheromone. RESULTS: Using wild-stock house mice to ensure natural responses that generalize across individual genomes, we identify a single atypical male-specific major urinary protein (MUP) of mass 18893Da that invokes a female's inherent sexual attraction to male compared to female urinary scent. Attraction to this protein pheromone, which we named darcin, was as strong as the attraction to intact male urine. Importantly, contact with darcin also stimulated a strong learned attraction to the associated airborne urinary odour of an individual male, such that, subsequently, females were attracted to the airborne scent of that specific individual but not to that of other males. CONCLUSIONS: This involatile protein is a mammalian male sex pheromone that stimulates a flexible response to individual-specific odours through associative learning and memory, allowing female sexual attraction to be inherent but selective towards particular males. This 'darcin effect' offers a new system to investigate the neural basis of individual-specific memories in the brain and give new insights into the regulation of behaviour in complex social mammals.See associated Commentary http://www.biomedcentral.com/1741-7007/8/71.


Subject(s)
Association Learning/physiology , Memory/physiology , Odorants , Proteins/metabolism , Sex Attractants/urine , Sexual Behavior, Animal/physiology , Animals , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Female , Gas Chromatography-Mass Spectrometry , Intercellular Signaling Peptides and Proteins , Male , Mice , Spectrometry, Mass, Electrospray Ionization
13.
Fungal Genet Biol ; 45(6): 1040-2, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18440253

ABSTRACT

Multi-locus sequencing data for 242 different isolates of Candida tropicalis generated a dendrogram showing 235 strains assigned to a single large recently evolved group which contained several small clonal clusters. Haplotype analysis of a representative strain subset revealed a high level of recombination events in an otherwise clonal population. Pairs of isolates from single sources showed non-identity attributable to loss of heterozygosity in some genes in a manner similar to that established for C. albicans.


Subject(s)
Candida tropicalis/classification , Candida tropicalis/genetics , Mycological Typing Techniques , Phylogeny , Candida albicans/genetics , Candida tropicalis/isolation & purification , Candidiasis/microbiology , Haplotypes , Humans , Polymorphism, Single Nucleotide , Recombination, Genetic
14.
Int J Med Microbiol ; 298(7-8): 663-8, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18165151

ABSTRACT

Multi-locus sequence typing data for 217 Candida albicans isolates cultured since 1990 from blood and vaginal samples in Japan, England/Wales and the USA were analysed for geographically related variations. While no significant differences were found between distributions of diploid sequence types (DSTs) in blood vs. vaginal isolates, there were highly significant differences in the clade distributions of isolates from the three geographical sources. Clade 2 strains were predominantly isolates from England/Wales, while clade 3 strains came mainly from the USA. The isolates from Japan were highly prevalent among strains in clades 5-17, and provided the first example seen so far in C. albicans of an amino acid encoded by three separate codons. Within clade 1, the most commonly encountered clade for isolates from all three regions, 15 Japanese isolates and 1 English isolate formed a separate clonal cluster in eBURST analysis. A similarly well demarcated clonal cluster rich in isolates from Japan was also found among the clade 4 strains. The data suggest C. albicans undergoes localized evolution, but human movements and person-to-person spread considerably blur the boundaries of such evolution.


Subject(s)
Candida albicans/classification , Candida albicans/isolation & purification , Candidiasis/microbiology , Blood/microbiology , Cluster Analysis , DNA Fingerprinting , DNA, Fungal/chemistry , DNA, Fungal/genetics , Female , Genotype , Humans , Japan , Molecular Epidemiology , Sequence Analysis, DNA/methods , Sequence Homology , United Kingdom , United States , Vagina/microbiology
15.
J Med Microbiol ; 56(Pt 8): 1066-1075, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17644714

ABSTRACT

A 12 month survey of candidaemia in Scotland, UK, in which every Scottish hospital laboratory submitted all blood isolates of yeasts for identification, strain typing and susceptibility testing, provided 300 isolates from 242 patients, generating incidence data of 4.8 cases per 100,000 population per year and 5.9 cases per 100,000 acute occupied bed days; 27.9 % of cases occurred in intensive care units. More than half the patients with candidaemia had an underlying disease involving the abdomen, 78 % had an indwelling intravenous catheter, 62 % had suffered a bacterial infection within the 2 weeks prior to candidaemia and 37 % had undergone a laparotomy. Candida albicans was the infecting species in 50 % of cases, followed by Candida glabrata (21 %) and Candida parapsilosis (12 %). Seven cases of candidaemia were caused by Candida dubliniensis, which was more prevalent even than Candida lusitaniae and Candida tropicalis (six cases each). Among C. glabrata isolates, 55 % showed reduced susceptibility to fluconazole, but azole resistance among other species was extremely low. Multilocus sequence typing showed isolates with high similarity came from different hospitals across the country, and many different types came from the hospitals that submitted the most isolates, indicating no tendency towards hospital-specific endemic strains. Multiple isolates of C. albicans and C. glabrata from individual patients were of the same strain type with single exceptions for each species. The high prevalence of candidaemia in Scotland, relative to other population-based European studies, and the high level of reduced fluconazole susceptibility of Scottish C. glabrata isolates warrant continued future surveillance of invasive Candida infections.


Subject(s)
Candida , Candidiasis/epidemiology , Fungemia/epidemiology , Adolescent , Adult , Aged , Antifungal Agents/pharmacology , Bacterial Infections , Candida/classification , Candida/drug effects , Candida/genetics , Catheters, Indwelling , Child , Child, Preschool , Female , Fluconazole/pharmacology , Health Surveys , Humans , Incidence , Infant , Laparotomy , Male , Microbial Sensitivity Tests , Middle Aged , Mycological Typing Techniques , Prospective Studies , Risk Factors , Scotland/epidemiology
16.
Eukaryot Cell ; 6(6): 1041-52, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17416899

ABSTRACT

We analyzed data on multilocus sequence typing (MLST), ABC typing, mating type-like locus (MAT) status, and antifungal susceptibility for a panel of 1,391 Candida albicans isolates. Almost all (96.7%) of the isolates could be assigned by MLST to one of 17 clades. eBURST analysis revealed 53 clonal clusters. Diploid sequence type 69 was the most common MLST strain type and the founder of the largest clonal cluster, and examples were found among isolates from all parts of the world. ABC types and geographical origins showed statistically significant variations among clades by univariate analysis of variance, but anatomical source and antifungal susceptibility data were not significantly associated. A separate analysis limited to European isolates, thereby minimizing geographical effects, showed significant differences in the proportions of isolates from blood, commensal carriage, and superficial infections among the five most populous clades. The proportion of isolates with low antifungal susceptibility was highest for MAT homozygous a/a types and then alpha/alpha types and was lowest for heterozygous a/alpha types. The tree of clades defined by MLST was not congruent with trees generated from the individual gene fragments sequenced, implying a separate evolutionary history for each fragment. Analysis of nucleic acid variation among loci and within loci supported recombination. Computational haplotype analysis showed a high frequency of recombination events, suggesting that isolates had mixed evolutionary histories resembling those of a sexually reproducing species.


Subject(s)
Candida albicans , Evolution, Molecular , Genes, Mating Type, Fungal , Phylogeny , Base Sequence , Candida albicans/classification , Candida albicans/genetics , Drug Resistance, Fungal/genetics , Humans , Mycological Typing Techniques , Sequence Analysis, DNA
17.
J Clin Microbiol ; 43(11): 5593-600, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16272492

ABSTRACT

A system is described for typing isolates of the pathogenic fungus Candida tropicalis, based on sequence polymorphisms in fragments of six genes: ICL1, MDR1, SAPT2, SAPT4, XYR1, and ZWF1a. The system differentiated 87 diploid sequence types (DSTs) among a total of 106 isolates tested or 80 DSTs among 88 isolates from unique sources. Replicate isolates from the same source clustered together with high statistical similarity, with the exception of one isolate. However, a clade of very closely related isolates included replicate isolates from three different patients, as well as single isolates from eight other patients. This clade, provisionally designated clade 1, was one of three clusters of isolates with high statistical similarity. Five of six isolates in one cluster that may acquire clade status were resistant to flucytosine. This study adds C. tropicalis to Candida albicans and Candida glabrata as Candida species for which a multilocus sequence typing (MLST) system has been set up. The C. tropicalis MLST database can be accessed at http://pubmlst.org/ctropicalis/.


Subject(s)
Candida tropicalis/classification , Candidiasis/microbiology , Genes, Fungal/genetics , Animals , Candida tropicalis/drug effects , Candida tropicalis/genetics , Candida tropicalis/isolation & purification , Drug Resistance, Fungal , Flucytosine/pharmacology , Humans , Mycological Typing Techniques/methods , Polymorphism, Genetic , Sequence Analysis
18.
J Clin Microbiol ; 43(11): 5601-13, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16272493

ABSTRACT

We submitted a panel of 416 isolates of Candida albicans from separate sources to multilocus sequence typing (MLST). The data generated determined a population structure in which four major clades of closely related isolates were delineated, together with eight minor clades comprising five or more isolates. By Fisher's exact test, a statistically significant association was found between particular clades and the anatomical source, geographical source, ABC genotype, decade of isolation, and homozygosity versus heterozygosity at the mating type-like locus (MTL) of the isolates in the clade. However, these associations may have been influenced by confounding variables, since in a univariate analysis of variance, only the clade associations with ABC type and anatomical source emerged as statistically significant, providing the first indication of possible differences between C. albicans strain type clades and their propensity to infect or colonize different anatomical locations. There were no significant differences between clades with respect to distributions of isolates resistant to fluconazole, itraconazole, or flucytosine. However, the majority of flucytosine-resistant isolates belonged to clade 1, and these isolates, but not flucytosine-resistant isolates in other clades, bore a unique mutation in the FUR1 gene that probably accounts for their resistance. A significantly higher proportion of isolates resistant to fluconazole, itraconazole, and flucytosine were homozygous at the MTL, suggesting that antifungal pressure may trigger a common mechanism that leads both to resistance and to MTL homozygosity. The utility of MLST for determining clade assignments of clinical isolates will form the basis for strain selection for future research into C. albicans virulence.


Subject(s)
Candida albicans/classification , Candidiasis/microbiology , Analysis of Variance , Antifungal Agents/pharmacology , Blood/microbiology , Candida albicans/drug effects , Candida albicans/genetics , Drug Resistance, Fungal/genetics , Europe , Female , Genes, Fungal/genetics , Humans , Mycological Typing Techniques , North America , Oropharynx/microbiology , Phylogeny , Sequence Analysis , Species Specificity , Vagina/microbiology
19.
J Clin Microbiol ; 43(1): 284-92, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15634984

ABSTRACT

Two new species, Candida orthopsilosis and C. metapsilosis, are proposed to replace the existing designations of C. parapsilosis groups II and III, respectively. The species C. parapsilosis is retained for group I isolates. Attempts to construct a multilocus sequence typing scheme to differentiate individual strains of C. parapsilosis instead revealed fixed DNA sequence differences between pairs of subgroups in four genes: COX3, L1A1, SADH, and SYA1. PCR amplicons for sequencing were obtained for these four plus a further seven genes from 21 group I isolates. For nine group II isolates, PCR products were obtained from only 5 of the 11 genes, and for two group III isolates PCR products were obtained from a different set of 5 genes. Three of the PCR products from group II and III isolates differed in size from the group I products. Cluster analysis of sequence polymorphisms from COX3, SADH, and SYA1, which were common to the three groups, consistently separated the isolates into three distinct sets. All of these differences, together with DNA sequence similarities <90% in the ITS1 sequence, suggest the subgroups should be afforded species status. The near absence of DNA sequence variability among isolates of C. parapsilosis and relatively high levels of sequence variability among isolates of C. orthopsilosis suggest that the former species may have evolved very recently from the latter.


Subject(s)
Candida/classification , Fungal Proteins/genetics , Mycological Typing Techniques , Sequence Analysis, DNA , Base Sequence , Candida/genetics , Candidiasis/microbiology , DNA, Fungal/analysis , DNA, Ribosomal Spacer/analysis , Genetic Variation , Humans , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 5.8S/genetics
20.
J Clin Microbiol ; 42(8): 3475-82, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15297486

ABSTRACT

Seventeen laboratories participated in a study of interlaboratory reproducibility with caspofungin microdilution susceptibility testing against panels comprising 30 isolates of Candida spp. and 20 isolates of Aspergillus spp. The laboratories used materials supplied from a single source to determine the influence of growth medium (RPMI 1640 with or without glucose additions and antibiotic medium 3 [AM3]), the same incubation times (24 h and 48 h), and the same end point definition (partial or complete inhibition of growth) for the MIC of caspofungin. All tests were run in duplicate, and end points were determined both spectrophotometrically and visually. The results from almost all of the laboratories for quality control and reference Candida and Aspergillus isolates tested with fluconazole and itraconazole matched the NCCLS published values. However, considerable interlaboratory variability was seen in the results of the caspofungin tests. For Candida spp. the most consistent MIC data were generated with visual "prominent growth reduction" (MIC(2)) end points measured at 24 h in RPMI 1640, where 73.3% of results for the 30 isolates tested fell within a mode +/- one dilution range across all 17 laboratories. MIC(2) at 24 h in RPMI 1640 or AM3 also gave the best interlaboratory separation of Candida isolates of known high and low susceptibility to caspofungin. Reproducibility of MIC data was problematic for caspofungin tests with Aspergillus spp. under all conditions, but the minimal effective concentration end point, defined as the lowest caspofungin concentration yielding conspicuously aberrant hyphal growth, gave excellent reproducibility for data from 14 of the 17 participating laboratories.


Subject(s)
Antifungal Agents/pharmacology , Aspergillus/drug effects , Candida/drug effects , Laboratories/standards , Microbial Sensitivity Tests/standards , Peptides, Cyclic , Peptides/pharmacology , Aspergillus/isolation & purification , Candida/isolation & purification , Caspofungin , Echinocandins , Fluconazole/pharmacology , Geography , Humans , Lipopeptides , Quality Control , Reproducibility of Results
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