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1.
Nature ; 625(7996): 760-767, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092039

RESUMO

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with ß-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.


Assuntos
Fator 15 de Diferenciação de Crescimento , Hiperêmese Gravídica , Náusea , Vômito , Animais , Feminino , Humanos , Camundongos , Gravidez , Talassemia beta/sangue , Talassemia beta/metabolismo , Feto/metabolismo , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/metabolismo , Hormônios/sangue , Hormônios/metabolismo , Hiperêmese Gravídica/complicações , Hiperêmese Gravídica/metabolismo , Hiperêmese Gravídica/prevenção & controle , Hiperêmese Gravídica/terapia , Náusea/sangue , Náusea/complicações , Náusea/metabolismo , Placenta/metabolismo , Vômito/sangue , Vômito/complicações , Vômito/metabolismo
2.
J Clin Microbiol ; 62(2): e0114023, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38265207

RESUMO

Candida glabrata is one of the most common causes of systemic candidiasis, often resistant to antifungal medications. To describe the genomic context of emerging resistance, we conducted a retrospective analysis of 82 serially collected isolates from 33 patients from population-based candidemia surveillance in the United States. We used whole-genome sequencing to determine the genetic relationships between isolates obtained from the same patient. Phylogenetic analysis demonstrated that isolates from 29 patients were clustered by patient. The median SNPs between isolates from the same patient was 30 (range: 7-96 SNPs), while unrelated strains infected four patients. Twenty-one isolates were resistant to echinocandins, and 24 were resistant to fluconazole. All echinocandin-resistant isolates carried a mutation either in the FKS1 or FKS2 HS1 region. Of the 24 fluconazole-resistant isolates, 17 (71%) had non-synonymous polymorphisms in the PDR1 gene, which were absent in susceptible isolates. In 11 patients, a genetically related resistant isolate was collected after recovering susceptible isolates, indicating in vivo acquisition of resistance. These findings allowed us to estimate the intra-host diversity of C. glabrata and propose an upper boundary of 96 SNPs for defining genetically related isolates, which can be used to assess donor-to-host transmission, nosocomial transmission, or acquired resistance. IMPORTANCE In our study, mutations associated to azole resistance and echinocandin resistance were detected in Candida glabrata isolates using a whole-genome sequence. C. glabrata is the second most common cause of candidemia in the United States, which rapidly acquires resistance to antifungals, in vitro and in vivo.


Assuntos
Candidemia , Equinocandinas , Humanos , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Candida glabrata , Candidemia/microbiologia , Estudos Retrospectivos , Filogenia , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Mutação , Genômica , Farmacorresistência Fúngica/genética
3.
Clin Exp Immunol ; 212(1): 52-60, 2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-36722378

RESUMO

Inflammation plays a fundamental role in the development of several metabolic diseases, including obesity and type 2 diabetes (T2D); the complement system has been implicated in their development. People of Black African (BA) ethnicity are disproportionately affected by T2D and other metabolic diseases but the impact of ethnicity on the complement system has not been explored. We investigated ethnic differences in complement biomarkers and activation status between men of BA and White European (WE) ethnicity and explored their association with parameters of metabolic health. We measured a panel of 15 complement components, regulators, and activation products in fasting plasma from 89 BA and 96 WE men. Ethnic differences were statistically validated. Association of complement biomarkers with metabolic health indices (BMI, waist circumference, insulin resistance, and HbA1c) were assessed in the groups. Plasma levels of the key complement components C3 and C4, the regulators clusterin and properdin and the activation marker iC3b were significantly higher in BA compared to WE men after age adjustment, while FD levels were significantly lower. C3 and C4 levels positively correlated with some or all markers of metabolic dysfunction in both ethnic groups while FD was inversely associated with HbA1c in both groups, and clusterin and properdin were inversely associated with some markers of metabolic dysfunction only in the WE group. Our findings of increased levels of complement components and activation products in BA compared to WE men suggest differences in complement regulation that may impact susceptibility to poor metabolic health.


Assuntos
Clusterina , Resistência à Insulina , Doenças Metabólicas , Properdina , Humanos , Masculino , Biomarcadores , Diabetes Mellitus Tipo 2 , Etnicidade , Hemoglobinas Glicadas , População Branca , População Negra , Doenças Metabólicas/etnologia , Complemento C4 , Complemento C3
4.
Anaesthesia ; 77(10): 1129-1136, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36089858

RESUMO

The primary aim of this review was to identify, analyse and codify the prominence and nature of human factors and ergonomics within difficult airway management algorithms. A directed search across OVID Medline and PubMed databases was performed. All articles were screened for relevance to the research aims and according to predetermined exclusion criteria. We identified 26 published airway management algorithms. A coding framework was iteratively developed identifying human factors and ergonomic specific words and phrases based on the Systems Engineering Initiative for Patient Safety model. This framework was applied to the papers to delineate qualitative and quantitative results. Our results show that human factors are well represented within recent airway management guidelines. Human factors associated with work systems and processes featured more prominently than user and patient outcome measurement and adaption. Human factors are an evolving area in airway management and our results highlight that further considerations are necessary in further guideline development.


Assuntos
Manuseio das Vias Aéreas , Ergonomia , Humanos , Prevalência
5.
Stud Mycol ; 100: 100133, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34909054

RESUMO

Candida glabrata is the second leading cause of candidemia in many countries and is one of the most concerning yeast species of nosocomial importance due to its increasing rate of antifungal drug resistance and emerging multidrug-resistant isolates. Application of multilocus sequence typing (MLST) to clinical C. glabrata isolates revealed an association of certain sequence types (STs) with drug resistance and mortality. The current C. glabrata MLST scheme is based on single nucleotide polymorphisms (SNPs) at six loci and is therefore relatively laborious and costly. Furthermore, only a few high-quality C. glabrata reference genomes are available, limiting rapid analysis of clinical isolates by whole genome sequencing. In this study we provide long-read based assemblies for seven additional clinical strains belonging to three different STs and use this information to simplify the C. glabrata MLST scheme. Specifically, a comparison of these genomes identified highly polymorphic loci (HPL) defined by frequent insertions and deletions (indels), two of which proved to be highly resolutive for ST. When challenged with 53 additional isolates, a combination of TRP1 (a component of the current MLST scheme) with either of the two HPL fully recapitulated ST identification. Therefore, our comparative genomic analysis identified a new typing approach combining SNPs and indels and based on only two loci, thus significantly simplifying ST identification in C. glabrata. Because typing tools are instrumental in addressing numerous clinical and biological questions, our new MLST scheme can be used for high throughput typing of C. glabrata in clinical and research settings.

7.
8.
Anaesthesia ; 73(6): 703-710, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29533465

RESUMO

In this exploratory study we describe the utility of smartphone technology for anonymous retrospective observational data collection of emergency front-of-neck airway management. The medical community continues to debate the optimal technique for emergency front-of-neck airway management. Although individual clinicians infrequently perform this procedure, hundreds are performed annually worldwide. Ubiquitous smartphone technology and internet connectivity have created the opportunity to collect these data. We created the 'Airway App', a smartphone application to capture the experiences of healthcare providers involved in emergency front-of-neck airway procedures. In the first 18-month period, 104 emergency front-of-neck airway management reports were received; 99 (95%) were internally valid and unique from 21 countries. Eighty-one (82%) were performed by non-surgeons and 63 (64%) were 'cannot intubate, cannot oxygenate' emergencies. Overall first-attempt success varied by technique; 45 scalpel-bougie cricothyroidotomy (37 first-attempt success), 25 surgical cricothyroidotomy (15 first-attempt success), eight cannula cricothyroidotomy (five first-attempt success), six wire-guided cricothyroidotomy (three first-attempt success) and 15 tracheostomy reports (11 first-attempt success). The most commonly reported positive human factors were good communication, good teamwork and/or skilled personnel. The most commonly reported negative human factors were fixation on multiple tracheal intubation attempts, delay in initiating emergency front-of-neck airway and/or the failure to plan for failure. Due to the anonymous nature of reporting, reports are open to recollection bias and spurious reporting. We conclude collection of data using a smartphone application is feasible and has the potential to expand our knowledge of emergency front-of-neck airway management.


Assuntos
Manuseio das Vias Aéreas/métodos , Aplicativos Móveis , Pescoço/cirurgia , Smartphone , Adulto , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Comunicação , Cartilagem Cricoide/cirurgia , Coleta de Dados , Serviços Médicos de Emergência , Feminino , Humanos , Intubação Intratraqueal , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Gravidez , Estudos Retrospectivos , Inquéritos e Questionários , Traqueostomia , Traqueotomia/estatística & dados numéricos
9.
Am J Transplant ; 17(1): 296-299, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28029734

RESUMO

November 11, 2016/65(44);1234-1237. What is already known about this topic? Candida auris is an emerging pathogenic fungus that has been reported from at least a dozen countries on four continents during 2009-2015. The organism is difficult to identify using traditional biochemical methods, some isolates have been found to be resistant to all three major classes of antifungal medications, and C. auris has caused health care-associated outbreaks. What is added by this report? This is the first description of C. auris cases in the United States. C. auris appears to have emerged in the United States only in the last few years, and U.S. isolates are related to isolates from South America and South Asia. Evidence from U.S. case investigations suggests likely transmission of the organism occurred in health care settings. What are the implications for public health practice? It is important that U.S. laboratories accurately identify C. auris and for health care facilities to implement recommended infection control practices to prevent the spread of C. auris. Local and state health departments and CDC should be notified of possible cases of C. auris and of isolates of C. haemulonii and Candida spp. that cannot be identified after routine testing.


Assuntos
Candida/isolamento & purificação , Candidíase/diagnóstico , Candidíase/microbiologia , Farmacorresistência Fúngica Múltipla , Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Doenças Transmissíveis Emergentes , Saúde Global , Humanos , Prognóstico , Fatores de Risco , Fatores de Tempo , Estados Unidos
10.
Antimicrob Agents Chemother ; 59(11): 6725-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282428

RESUMO

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Anidulafungina , Candida/genética , Caspofungina , Micafungina , Testes de Sensibilidade Microbiana , Mutação/genética
11.
Transpl Infect Dis ; 17(3): 467-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25677448

RESUMO

Cryptococcus gattii was recognized as an emerging infection in the Pacific Northwest in 2004. Out of 62 total infections in Oregon since the outbreak, 11 were in solid organ transplant (SOT) recipients. SOT recipients were more likely to have disseminated disease and higher mortality than normal hosts, who mostly had isolated mass lesions. The median time from transplantation to C. gattii diagnosis was 17.8 months. The primary sites of infection were lung (n = 4), central nervous system (n = 3), or both (n = 4). The Oregon-endemic strain, VGII (subtypes IIa and IIc) was present in 10 of 11 patients; the median fluconazole minimum inhibitory concentration (MIC) was 12 µg/mL (range 2-32 µg/mL) for this strain. We found C. gattii infection among organ transplant recipients was disseminated at diagnosis, had low cerebrospinal fluid cryptococcal antigen titers, and was associated with an elevated fluconazole MIC and high attributable mortality.


Assuntos
Antígenos de Fungos/líquido cefalorraquidiano , Criptococose/diagnóstico , Cryptococcus gattii/isolamento & purificação , Surtos de Doenças , Fluconazol/farmacologia , Transplante de Órgãos/efeitos adversos , Criptococose/microbiologia , Cryptococcus gattii/classificação , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/imunologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Oregon/epidemiologia , Estudos Retrospectivos , Transplantados
13.
Antimicrob Agents Chemother ; 58(2): 916-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24277027

RESUMO

Since epidemiological cutoff values (ECVs) using CLSI MICs from multiple laboratories are not available for Candida spp. and the echinocandins, we established ECVs for anidulafungin and micafungin on the basis of wild-type (WT) MIC distributions (for organisms in a species-drug combination with no detectable acquired resistance mechanisms) for 8,210 Candida albicans, 3,102 C. glabrata, 3,976 C. parapsilosis, 2,042 C. tropicalis, 617 C. krusei, 258 C. lusitaniae, 234 C. guilliermondii, and 131 C. dubliniensis isolates. CLSI broth microdilution MIC data gathered from 15 different laboratories in Canada, Europe, Mexico, Peru, and the United States were aggregated to statistically define ECVs. ECVs encompassing 97.5% of the statistically modeled population for anidulafungin and micafungin were, respectively, 0.12 and 0.03 µg/ml for C. albicans, 0.12 and 0.03 µg/ml for C. glabrata, 8 and 4 µg/ml for C. parapsilosis, 0.12 and 0.06 µg/ml for C. tropicalis, 0.25 and 0.25 µg/ml for C. krusei, 1 and 0.5 µg/ml for C. lusitaniae, 8 and 2 µg/ml for C. guilliermondii, and 0.12 and 0.12 µg/ml for C. dubliniensis. Previously reported single and multicenter ECVs defined in the present study were quite similar or within 1 2-fold dilution of each other. For a collection of 230 WT isolates (no fks mutations) and 51 isolates with fks mutations, the species-specific ECVs for anidulafungin and micafungin correctly classified 47 (92.2%) and 51 (100%) of the fks mutants, respectively, as non-WT strains. These ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin and micafungin due to fks mutations.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Proteínas Fúngicas/genética , Lipopeptídeos/farmacologia , Anidulafungina , Candida/classificação , Candida/genética , Candida/isolamento & purificação , Candidíase/epidemiologia , Candidíase/microbiologia , Europa (Continente)/epidemiologia , Expressão Gênica , Humanos , Micafungina , Testes de Sensibilidade Microbiana , Mutação , América do Norte/epidemiologia , América do Sul/epidemiologia
14.
Antimicrob Agents Chemother ; 58(4): 2006-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24419346

RESUMO

Although epidemiological cutoff values (ECVs) have been established for Candida spp. and the triazoles, they are based on MIC data from a single laboratory. We have established ECVs for eight Candida species and fluconazole, posaconazole, and voriconazole based on wild-type (WT) MIC distributions for isolates of C. albicans (n=11,241 isolates), C. glabrata (7,538), C. parapsilosis (6,023), C. tropicalis (3,748), C. krusei (1,073), C. lusitaniae (574), C. guilliermondii (373), and C. dubliniensis (162). The 24-h CLSI broth microdilution MICs were collated from multiple laboratories (in Canada, Brazil, Europe, Mexico, Peru, and the United States). The ECVs for distributions originating from ≥6 laboratories, which included ≥95% of the modeled WT population, for fluconazole, posaconazole, and voriconazole were, respectively, 0.5, 0.06 and 0.03 µg/ml for C. albicans, 0.5, 0.25, and 0.03 µg/ml for C. dubliniensis, 8, 1, and 0.25 µg/ml for C. glabrata, 8, 0.5, and 0.12 µg/ml for C. guilliermondii, 32, 0.5, and 0.25 µg/ml for C. krusei, 1, 0.06, and 0.06 µg/ml for C. lusitaniae, 1, 0.25, and 0.03 µg/ml for C. parapsilosis, and 1, 0.12, and 0.06 µg/ml for C. tropicalis. The low number of MICs (<100) for other less prevalent species (C. famata, C. kefyr, C. orthopsilosis, C. rugosa) precluded ECV definition, but their MIC distributions are documented. Evaluation of our ECVs for some species/agent combinations using published individual MICs for 136 isolates (harboring mutations in or upregulation of ERG11, MDR1, CDR1, or CDR2) and 64 WT isolates indicated that our ECVs may be useful in distinguishing WT from non-WT isolates.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Fluconazol/farmacologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Testes de Sensibilidade Microbiana , Voriconazol
15.
Antimicrob Agents Chemother ; 57(12): 5836-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24018263

RESUMO

Although Clinical and Laboratory Standards Institute (CLSI) clinical breakpoints (CBPs) are available for interpreting echinocandin MICs for Candida spp., epidemiologic cutoff values (ECVs) based on collective MIC data from multiple laboratories have not been defined. While collating CLSI caspofungin MICs for 145 to 11,550 Candida isolates from 17 laboratories (Brazil, Canada, Europe, Mexico, Peru, and the United States), we observed an extraordinary amount of modal variability (wide ranges) among laboratories as well as truncated and bimodal MIC distributions. The species-specific modes across different laboratories ranged from 0.016 to 0.5 µg/ml for C. albicans and C. tropicalis, 0.031 to 0.5 µg/ml for C. glabrata, and 0.063 to 1 µg/ml for C. krusei. Variability was also similar among MIC distributions for C. dubliniensis and C. lusitaniae. The exceptions were C. parapsilosis and C. guilliermondii MIC distributions, where most modes were within one 2-fold dilution of each other. These findings were consistent with available data from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) (403 to 2,556 MICs) for C. albicans, C. glabrata, C. krusei, and C. tropicalis. Although many factors (caspofungin powder source, stock solution solvent, powder storage time length and temperature, and MIC determination testing parameters) were examined as a potential cause of such unprecedented variability, a single specific cause was not identified. Therefore, it seems highly likely that the use of the CLSI species-specific caspofungin CBPs could lead to reporting an excessive number of wild-type (WT) isolates (e.g., C. glabrata and C. krusei) as either non-WT or resistant isolates. Until this problem is resolved, routine testing or reporting of CLSI caspofungin MICs for Candida is not recommended; micafungin or anidulafungin data could be used instead.


Assuntos
Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Equinocandinas/uso terapêutico , Anidulafungina , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candidíase/microbiologia , Caspofungina , Farmacorresistência Fúngica , Europa (Continente) , Humanos , Lipopeptídeos/uso terapêutico , Micafungina , Testes de Sensibilidade Microbiana/normas , Testes de Sensibilidade Microbiana/estatística & dados numéricos , América do Norte , Variações Dependentes do Observador , América do Sul , Especificidade da Espécie
16.
Transpl Infect Dis ; 15(2): E64-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23387927

RESUMO

Initial presentation of invasive fungal infections such as histoplasmosis can include non-specific clinical manifestations, especially in immunocompromised patients. A high index of suspicion is required to identify atypical manifestations of these diseases, which carry a high risk of mortality, if the diagnosis is delayed or missed. We describe a case of a kidney transplant recipient with cutaneous lesions as initial manifestation of progressive disseminated histoplasmosis where a skin biopsy was crucial to an early diagnosis.


Assuntos
Dermatomicoses/diagnóstico , Histoplasmose/diagnóstico , Transplante de Rim , Adulto , Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Feminino , Histoplasmose/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Itraconazol/uso terapêutico , Ohio , Complicações Pós-Operatórias , Fatores de Tempo , Resultado do Tratamento , População Branca
17.
bioRxiv ; 2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37398065

RESUMO

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

18.
Antimicrob Agents Chemother ; 56(6): 3107-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22391546

RESUMO

Clinical breakpoints (CBPs) are not available for the Cryptococcus neoformans-Cryptococcus gattii species complex. MIC distributions were constructed for the wild type (WT) to establish epidemiologic cutoff values (ECVs) for C. neoformans and C. gattii versus amphotericin B and flucytosine. A total of 3,590 amphotericin B and 3,045 flucytosine CLSI MICs for C. neoformans (including 1,002 VNI isolates and 8 to 39 VNII, VNIII, and VNIV isolates) and 985 and 853 MICs for C. gattii, respectively (including 42 to 259 VGI, VGII, VGIII, and VGIV isolates), were gathered in 9 to 16 (amphotericin B) and 8 to 13 (flucytosine) laboratories (Europe, United States, Australia, Brazil, Canada, India, and South Africa) and aggregated for the analyses. Additionally, 442 amphotericin B and 313 flucytosine MICs measured by using CLSI-YNB medium instead of CLSI-RPMI medium and 237 Etest amphotericin B MICs for C. neoformans were evaluated. CLSI-RPMI ECVs for distributions originating in ≥3 laboratories (with the percentages of isolates for which MICs were less than or equal to ECVs given in parentheses) were as follows: for amphotericin B, 0.5 µg/ml for C. neoformans VNI (97.2%) and C. gattii VGI and VGIIa (99.2 and 97.5%, respectively) and 1 µg/ml for C. neoformans (98.5%) and C. gattii nontyped (100%) and VGII (99.2%) isolates; for flucytosine, 4 µg/ml for C. gattii nontyped (96.4%) and VGI (95.7%) isolates, 8 µg/ml for VNI (96.6%) isolates, and 16 µg/ml for C. neoformans nontyped (98.6%) and C. gattii VGII (97.1%) isolates. Other molecular types had apparent variations in MIC distributions, but the number of laboratories contributing data was too low to allow us to ascertain that the differences were due to factors other than assay variation. ECVs may aid in the detection of isolates with acquired resistance mechanisms.


Assuntos
Anfotericina B/farmacologia , Antibacterianos/farmacologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Flucitosina/farmacologia , Testes de Sensibilidade Microbiana
19.
Antimicrob Agents Chemother ; 56(11): 5898-906, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22948877

RESUMO

Epidemiological cutoff values (ECVs) for the Cryptococcus neoformans-Cryptococcus gattii species complex versus fluconazole, itraconazole, posaconazole, and voriconazole are not available. We established ECVs for these species and agents based on wild-type (WT) MIC distributions. A total of 2,985 to 5,733 CLSI MICs for C. neoformans (including isolates of molecular type VNI [MICs for 759 to 1,137 isolates] and VNII, VNIII, and VNIV [MICs for 24 to 57 isolates]) and 705 to 975 MICs for C. gattii (including 42 to 260 for VGI, VGII, VGIII, and VGIV isolates) were gathered in 15 to 24 laboratories (Europe, United States, Argentina, Australia, Brazil, Canada, Cuba, India, Mexico, and South Africa) and were aggregated for analysis. Additionally, 220 to 359 MICs measured using CLSI yeast nitrogen base (YNB) medium instead of CLSI RPMI medium for C. neoformans were evaluated. CLSI RPMI medium ECVs for distributions originating from at least three laboratories, which included ≥95% of the modeled WT population, were as follows: fluconazole, 8 µg/ml (VNI, C. gattii nontyped, VGI, VGIIa, and VGIII), 16 µg/ml (C. neoformans nontyped, VNIII, and VGIV), and 32 µg/ml (VGII); itraconazole, 0.25 µg/ml (VNI), 0.5 µg/ml (C. neoformans and C. gattii nontyped and VGI to VGIII), and 1 µg/ml (VGIV); posaconazole, 0.25 µg/ml (C. neoformans nontyped and VNI) and 0.5 µg/ml (C. gattii nontyped and VGI); and voriconazole, 0.12 µg/ml (VNIV), 0.25 µg/ml (C. neoformans and C. gattii nontyped, VNI, VNIII, VGII, and VGIIa,), and 0.5 µg/ml (VGI). The number of laboratories contributing data for other molecular types was too low to ascertain that the differences were due to factors other than assay variation. In the absence of clinical breakpoints, our ECVs may aid in the detection of isolates with acquired resistance mechanisms and should be listed in the revised CLSI M27-A3 and CLSI M27-S3 documents.


Assuntos
Antifúngicos/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/epidemiologia , Cryptococcus gattii/efeitos dos fármacos , Fluconazol/uso terapêutico , Itraconazol/uso terapêutico , Pirimidinas/uso terapêutico , Triazóis/uso terapêutico , Antifúngicos/farmacologia , Austrália/epidemiologia , Criptococose/microbiologia , Cryptococcus gattii/crescimento & desenvolvimento , Cryptococcus gattii/isolamento & purificação , Farmacorresistência Fúngica/efeitos dos fármacos , Europa (Continente)/epidemiologia , Fluconazol/farmacologia , Humanos , Índia/epidemiologia , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana , América do Norte/epidemiologia , Pirimidinas/farmacologia , África do Sul/epidemiologia , América do Sul/epidemiologia , Triazóis/farmacologia , Voriconazol
20.
J Clin Microbiol ; 50(4): 1199-203, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22278842

RESUMO

The echinocandin class of antifungal agents is considered to be the first-line treatment of bloodstream infections (BSI) due to Candida glabrata. Recent reports of BSI due to strains of C. glabrata resistant to both fluconazole and the echinocandins are of concern and prompted us to review the experience of two large surveillance programs, the SENTRY Antimicrobial Surveillance Program for the years 2006 through 2010 and the Centers for Disease Control and Prevention population-based surveillance conducted in 2008 to 2010. The in vitro susceptibilities of 1,669 BSI isolates of C. glabrata to fluconazole, voriconazole, anidulafungin, caspofungin, and micafungin were determined by CLSI broth microdilution methods. Fluconazole MICs of ≥64 µg/ml were considered resistant. Strains for which anidulafungin and caspofungin MICs were ≥0.5 µg/ml and for which micafungin MICs were ≥0.25 µg/ml were considered resistant. A total of 162 isolates (9.7%) were resistant to fluconazole, of which 98.8% were nonsusceptible to voriconazole (MIC > 0.5 µg/ml) and 9.3%, 9.3%, and 8.0% were resistant to anidulafungin, caspofungin, and micafungin, respectively. There were 18 fluconazole-resistant isolates that were resistant to one or more of the echinocandins (11.1% of all fluconazole-resistant isolates), all of which contained an acquired mutation in fks1 or fks2. By comparison, there were no echinocandin-resistant strains detected among 110 fluconazole-resistant isolates of C. glabrata tested in 2001 to 2004. These data document the broad emergence of coresistance over time to both azoles and echinocandins in clinical isolates of C. glabrata.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Candidemia/microbiologia , Farmacorresistência Fúngica Múltipla/genética , Equinocandinas/farmacologia , Fluconazol/farmacologia , Adulto , Idoso , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Feminino , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Vigilância de Evento Sentinela , Adulto Jovem
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