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1.
Nature ; 556(7700): 223-226, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29643486

RESUMO

From dice to modern electronic circuits, there have been many attempts to build better devices to generate random numbers. Randomness is fundamental to security and cryptographic systems and to safeguarding privacy. A key challenge with random-number generators is that it is hard to ensure that their outputs are unpredictable1-3. For a random-number generator based on a physical process, such as a noisy classical system or an elementary quantum measurement, a detailed model that describes the underlying physics is necessary to assert unpredictability. Imperfections in the model compromise the integrity of the device. However, it is possible to exploit the phenomenon of quantum non-locality with a loophole-free Bell test to build a random-number generator that can produce output that is unpredictable to any adversary that is limited only by general physical principles, such as special relativity1-11. With recent technological developments, it is now possible to carry out such a loophole-free Bell test12-14,22. Here we present certified randomness obtained from a photonic Bell experiment and extract 1,024 random bits that are uniformly distributed to within 10-12. These random bits could not have been predicted according to any physical theory that prohibits faster-than-light (superluminal) signalling and that allows independent measurement choices. To certify and quantify the randomness, we describe a protocol that is optimized for devices that are characterized by a low per-trial violation of Bell inequalities. Future random-number generators based on loophole-free Bell tests may have a role in increasing the security and trust of our cryptographic systems and infrastructure.

2.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34593630

RESUMO

Magnetic resonance fingerprinting (MRF) is a method to extract quantitative tissue properties such as [Formula: see text] and [Formula: see text] relaxation rates from arbitrary pulse sequences using conventional MRI hardware. MRF pulse sequences have thousands of tunable parameters, which can be chosen to maximize precision and minimize scan time. Here, we perform de novo automated design of MRF pulse sequences by applying physics-inspired optimization heuristics. Our experimental data suggest that systematic errors dominate over random errors in MRF scans under clinically relevant conditions of high undersampling. Thus, in contrast to prior optimization efforts, which focused on statistical error models, we use a cost function based on explicit first-principles simulation of systematic errors arising from Fourier undersampling and phase variation. The resulting pulse sequences display features qualitatively different from previously used MRF pulse sequences and achieve fourfold shorter scan time than prior human-designed sequences of equivalent precision in [Formula: see text] and [Formula: see text] Furthermore, the optimization algorithm has discovered the existence of MRF pulse sequences with intrinsic robustness against shading artifacts due to phase variation.


Assuntos
Imageamento por Ressonância Magnética/métodos , Algoritmos , Automação , Encéfalo/diagnóstico por imagem , Simulação por Computador , Epilepsia/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Imagens de Fantasmas
3.
J Infect Dis ; 228(8): 1119-1126, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37163744

RESUMO

BACKGROUND: Natural clearance of Chlamydia trachomatis in women occurs in the interval between screening and treatment. In vitro, interferon-γ (IFN-γ)-mediated tryptophan depletion results in C. trachomatis clearance, but whether this mechanism occurs in vivo remains unclear. We previously found that women who naturally cleared C. trachomatis had lower cervicovaginal levels of tryptophan and IFN-γ compared to women with persisting infection, suggesting IFN-γ-independent pathways may promote C. trachomatis clearance. METHODS: Cervicovaginal lavages from 34 women who did (n = 17) or did not (n = 17) naturally clear C. trachomatis were subjected to untargeted high-performance liquid chromatography mass-spectrometry to identify metabolites and metabolic pathways associated with natural clearance. RESULTS: In total, 375 positively charged metabolites and 149 negatively charged metabolites were annotated. Compared to women with persisting infection, C. trachomatis natural clearance was associated with increased levels of oligosaccharides trehalose, sucrose, melezitose, and maltotriose, and lower levels of indoline and various amino acids. Metabolites were associated with valine, leucine, and isoleucine biosynthesis pathways. CONCLUSIONS: The cervicovaginal metabolome in women who did or did not naturally clear C. trachomatis is distinct. In women who cleared C. trachomatis, depletion of various amino acids, especially valine, leucine, and isoleucine, suggests that amino acids other than tryptophan impact C. trachomatis survival in vivo.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Feminino , Humanos , Triptofano/metabolismo , Leucina , Isoleucina/metabolismo , Infecções por Chlamydia/metabolismo , Aminoácidos/metabolismo , Interferon gama/metabolismo , Valina/metabolismo
4.
Clin Infect Dis ; 77(10): 1449-1459, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37402645

RESUMO

BACKGROUND: Mycoplasma genitalium (MG) is on the CDC Watch List of Antimicrobial Resistance Threats, yet there is no systematic surveillance to monitor change. METHODS: We initiated surveillance in sexual health clinics in 6 cities, selecting a quota sample of urogenital specimens tested for gonorrhea and/or chlamydia. We abstracted patient data from medical records and detected MG and macrolide-resistance mutations (MRMs) by nucleic acid amplification testing. We used Poisson regression to estimate adjusted prevalence ratios (aPRs) and 95% CIs, adjusting for sampling criteria (site, birth sex, symptom status). RESULTS: From October-December 2020 we tested 1743 urogenital specimens: 57.0% from males, 46.1% from non-Hispanic Black persons, and 43.8% from symptomatic patients. MG prevalence was 16.6% (95% CI: 14.9-18.5%; site-specific range: 9.9-23.5%) and higher in St Louis (aPR: 1.9; 1.27-2.85), Greensboro (aPR: 1.8; 1.18-2.79), and Denver (aPR: 1.7; 1.12-2.44) than Seattle. Prevalence was highest in persons <18 years (30.4%) and declined 3% per each additional year of age (aPR: .97; .955-.982). MG was detected in 26.8%, 21.1%, 11.8%, and 15.4% of urethritis, vaginitis, cervicitis, and pelvic inflammatory disease (PID), respectively. It was present in 9% of asymptomatic males and 15.4% of asymptomatic females, and associated with male urethritis (aPR: 1.7; 1.22-2.50) and chlamydia (aPR: 1.7; 1.13-2.53). MRM prevalence was 59.1% (95% CI: 53.1-64.8%; site-specific range: 51.3-70.6%). MRMs were associated with vaginitis (aPR: 1.8; 1.14-2.85), cervicitis (aPR: 3.5; 1.69-7.30), and PID cervicitis (aPR: 1.8; 1.09-3.08). CONCLUSIONS: MG infection is common in persons at high risk of sexually transmitted infections; testing symptomatic patients would facilitate appropriate therapy. Macrolide resistance is high and azithromycin should not be used without resistance testing.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Doença Inflamatória Pélvica , Saúde Sexual , Uretrite , Cervicite Uterina , Vaginite , Feminino , Humanos , Masculino , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Uretrite/tratamento farmacológico , Mycoplasma genitalium/genética , Cervicite Uterina/tratamento farmacológico , Macrolídeos/farmacologia , Macrolídeos/uso terapêutico , Farmacorresistência Bacteriana , Doença Inflamatória Pélvica/tratamento farmacológico , Vaginite/tratamento farmacológico , Infecções por Mycoplasma/diagnóstico , Prevalência
5.
Proc Natl Acad Sci U S A ; 117(41): 25396-25401, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33024018

RESUMO

Quantum computers and simulators may offer significant advantages over their classical counterparts, providing insights into quantum many-body systems and possibly improving performance for solving exponentially hard problems, such as optimization and satisfiability. Here, we report the implementation of a low-depth Quantum Approximate Optimization Algorithm (QAOA) using an analog quantum simulator. We estimate the ground-state energy of the Transverse Field Ising Model with long-range interactions with tunable range, and we optimize the corresponding combinatorial classical problem by sampling the QAOA output with high-fidelity, single-shot, individual qubit measurements. We execute the algorithm with both an exhaustive search and closed-loop optimization of the variational parameters, approximating the ground-state energy with up to 40 trapped-ion qubits. We benchmark the experiment with bootstrapping heuristic methods scaling polynomially with the system size. We observe, in agreement with numerics, that the QAOA performance does not degrade significantly as we scale up the system size and that the runtime is approximately independent from the number of qubits. We finally give a comprehensive analysis of the errors occurring in our system, a crucial step in the path forward toward the application of the QAOA to more general problem instances.

6.
Sex Transm Dis ; 49(1): 67-75, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34618416

RESUMO

BACKGROUND: In men with nongonococcal urethritis (NGU), clinicians and patients rely on clinical cure to guide the need for additional testing/treatment and when to resume sex, respectively; however, discordant clinical and microbiological cure outcomes do occur. How accurately clinical cure reflects microbiological cure in specific sexually transmitted infections (STIs) is unclear. METHODS: Men with NGU were tested for Neisseria gonorrhoeae, Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Trichomonas vaginalis, urethrotropic Neisseria meningitidis ST-11 clade strains, and Ureaplasma urealyticum (UU). Men received azithromycin 1 g and returned for a 1-month test-of-cure visit. In MG infections, we evaluated for the presence of macrolide resistance-mediating mutations (MRMs) and investigated alternate hypotheses for microbiological treatment failure using in situ shotgun metagenomic sequencing, phylogenetic analysis, multilocus sequence typing analyses, and quantitative PCR. RESULTS: Of 280 men with NGU, 121 were included in this analysis. In the monoinfection group, 52 had CT, 16 had MG, 7 had UU, 10 had mixed infection, and 36 men had idiopathic NGU. Clinical cure rates were 85% for CT, 100% for UU, 50% for MG, and 67% for idiopathic NGU. Clinical cure accurately predicted microbiological cure for all STIs, except MG. Discordant results were significantly associated with MG-NGU and predominantly reflected microbiological failure in men with clinical cure. Mycoplasma genitalium MRMs, but not MG load or strain, were strongly associated with microbiological failure. CONCLUSIONS: In azithromycin-treated NGU, clinical cure predicts microbiological cure for all STIs, except MG. Nongonococcal urethritis management should include MG testing and confirmation of microbiological cure in azithromycin-treated MG-NGU when MRM testing is unavailable.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Uretrite , Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Chlamydia trachomatis , Farmacorresistência Bacteriana , Humanos , Macrolídeos/uso terapêutico , Masculino , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/microbiologia , Mycoplasma genitalium/genética , Filogenia , Uretrite/diagnóstico , Uretrite/tratamento farmacológico , Uretrite/microbiologia
7.
Sex Transm Infect ; 96(4): 306-311, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31515293

RESUMO

OBJECTIVES: Chlamydia trachomatis (CT) and Mycoplasma genitalium (MG) cause the majority of non-gonococcal urethritis (NGU). The role of Ureaplasma urealyticum (UU) in NGU is unclear. Prior case-control studies that examined the association of UU and NGU may have been confounded by mixed infections and less stringent criteria for controls. The objective of this case-control study was to determine the prevalence and aetiology of mixed infections in men and assess if UU monoinfection is associated with NGU. METHODS: We identified 155 men with NGU and 103 controls. Behavioural and clinical information was obtained and men were tested for Neisseria gonorrhoeae and CT, MG, UU and Trichomonas vaginalis (TV). Men who were five-pathogen negative were classified as idiopathic urethritis (IU). RESULTS: Twelve per cent of NGU cases in which a pathogen was identified had mixed infections, mostly UU coinfections with MG or CT; 27% had IU. In monoinfected NGU cases, 34% had CT, 17% had MG, 11% had UU and 2% had TV. In controls, pathogens were rarely identified, except for UU, which was present in 20%. Comparing cases and controls, NGU was associated with CT and MG monoinfections and mixed infections. UU monoinfection was not associated with NGU and was almost twice as prevalent in controls. Men in both the case and control groups who were younger and who reported no prior NGU diagnosis were more likely to have UU (OR 0.97 per year of age, 95% CI 0.94 to 0.998 and OR 6.3, 95% CI 1.4 to 28.5, respectively). CONCLUSIONS: Mixed infections are common in men with NGU and most of these are UU coinfections with other pathogens that are well-established causes of NGU. UU monoinfections are not associated with NGU and are common in younger men and men who have never previously had NGU. Almost half of NGU cases are idiopathic.


Assuntos
Chlamydia trachomatis/isolamento & purificação , Coinfecção/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Trichomonas vaginalis/isolamento & purificação , Ureaplasma urealyticum/isolamento & purificação , Uretrite/epidemiologia , Adolescente , Adulto , Estudos de Casos e Controles , Coinfecção/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neisseria gonorrhoeae/isolamento & purificação , Prevalência , Uretrite/etiologia , Adulto Jovem
8.
Sex Transm Dis ; 47(5): 329-331, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32149960

RESUMO

Identifying pathogen-specific signs or symptoms of nongonococcal urethritis could improve syndromic management accuracy. We evaluated nongonococcal urethritis signs and symptoms in 220 men with single-pathogen infections (Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, or Ureaplasma urealyticum) or idiopathic urethritis. No individual sign or symptom accurately predicted the infectious etiology.


Assuntos
Mycoplasma genitalium , Uretra/microbiologia , Uretrite/diagnóstico , Adolescente , Adulto , Humanos , Indiana , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/diagnóstico , Mycoplasma genitalium/isolamento & purificação , Ureaplasma urealyticum/isolamento & purificação , Uretrite/microbiologia , Adulto Jovem
9.
J Sports Sci ; 38(18): 2063-2070, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32508221

RESUMO

The effects of acute ingestion of nitrate on short-duration repeated sprint performance (RSP) are unclear. This study investigated the effect of acute ingestion of beetroot juice on a test of RSP in team sport athletes. Sixteen male team sport athletes undertook four trials using a 40 m maximum shuttle run test (MST), which incorporates 10 × 40 m shuttle sprints with 30 s between the start of each sprint. Two familiarisation trials, followed by nitrate-rich beetroot juice (BR; ~6 mmol nitrate) and nitrate-depleted beetroot juice (PLA; ~0.0034 mmol nitrate) trials were completed in a randomised, double-blind manner. Ingestion of beetroot juice 3 h prior to exercise elevated plasma nitrate concentrations ~6-fold in BR (BR, 413 ± 56 µM; PLA, 69 ± 30 µM; P < 0.001). RSP, assessed by sprint performance decrement (Sdec; %), did not differ (P = 0.337) between BR (5.31 ± 2.49%) and PLA (5.71 ± 2.61%). There was no difference between trials for total sprint time (P = 0.806), fastest sprint (P = 0.341), slowest sprint (P = 0.787), or post-exercise blood lactate concentration (BR, 11.8 ± 2.5 mM; PLA, 12.2 ± 2.3 mM; P = 0.109). Therefore, acute ingestion of beetroot juice did not improve a test of short-duration RSP in team sport athletes.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Sucos de Frutas e Vegetais , Nitratos/administração & dosagem , Corrida/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Alimentos , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Fadiga Muscular/fisiologia , Nitratos/sangue , Adulto Jovem
10.
Cytokine ; 113: 458-461, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29914793

RESUMO

Chlamydia trachomatis infection (chlamydia) is the most prevalent sexually transmitted bacterial infection and causes significant reproductive morbidity in women. Little is known about how immunity to chlamydia develops in women, though animal models of chlamydia indicate that T-helper type 1 (Th1) responses are important for chlamydia clearance and protective immunity, whereas T-helper type 2 (Th2) responses are associated with persisting infection. In chlamydia-infected women, whether the predominant immune response is Th1- or Th2-polarizing remains controversial. To determine the cytokine profiles elicited by peripheral blood mononuclear cells (PBMCs) from chlamydia-infected women, we stimulated PBMCs with C. trachomatis elementary bodies and recombinant C. trachomatis Pgp3 and measured supernatant levels of select cytokines spanning Th1- and Th2-polarizing responses. We found that stimulated PBMCs from chlamydia-infected women secreted cytokines that indicate strong Th1-polarizing responses, especially interferon-gamma, whereas Th2-polarizing cytokines were expressed at significantly lower levels. In chlamydia-infected women, the predominant cytokine responses elicited on stimulation of PBMCs with C. trachomatis antigens were Th1-polarizing, with interferon-gamma as the predominant cytokine.


Assuntos
Chlamydia trachomatis/imunologia , Citocinas , Linfogranuloma Venéreo , Células Th1 , Adolescente , Adulto , Citocinas/sangue , Citocinas/imunologia , Feminino , Humanos , Linfogranuloma Venéreo/sangue , Linfogranuloma Venéreo/imunologia , Linfogranuloma Venéreo/patologia , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/patologia
11.
Sex Transm Dis ; 46(5): 317-320, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30985634

RESUMO

BACKGROUND: Symptom awareness, behavioral factors, and other barriers associated with timely sexually transmitted infection (STI) health care provision in men is not well studied. METHODS: Men attending an STI clinic answered a questionnaire regarding their symptoms, sexual behavior, and sociodemographic and behavioral characteristics. Characteristics of symptomatic men were compared between those who did and did not delay seeking health care services. Delayed care seeking was defined as clinic attendance longer than 7 days after symptoms, whereas early care seeking was defined as clinic attendance of 7 days or less. RESULTS: Over a quarter (n = 43 [27.7%]) of men with urethritis symptoms (urethral discharge or dysuria) delayed seeking care for more than 7 days. Compared with men who sought treatment within 7 days, those that delayed care worried for longer periods that their symptoms were STI-related, were more likely to attempt self-treatment of STI symptoms, were more likely to continue engaging in sexual activity, and were less likely to use a condom during their last sexual encounter. Conversely, men that delayed care seeking were less likely to have urethral discharge on physical examination, to have 5 or more polymorphonuclear leukocytes, and to test positive for Neisseria gonorrhoeae. When compared with men that sought care earlier, men that delayed care seeking had fewer overall and new partners in the past 30 days. CONCLUSIONS: Our data suggest that over a quarter of men aware of STI symptoms delay seeking health services. Interventions that promote better patient understanding of the importance of symptom recognition and that facilitate timely access to care may provide new opportunities to reduce STI transmission.


Assuntos
Infecções Sexualmente Transmissíveis/diagnóstico , Uretrite/diagnóstico , Adolescente , Adulto , Idoso , Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neisseria gonorrhoeae , Aceitação pelo Paciente de Cuidados de Saúde , Comportamento Sexual , Parceiros Sexuais , Fatores de Tempo , Adulto Jovem
12.
Sex Transm Dis ; 46(7): 440-445, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31194715

RESUMO

BACKGROUND: Rectal infection with Chlamydia trachomatis (CT) is frequent in women who deny receptive anal sex and is thought to arise from autoinoculation of the rectum from vaginal secretions. An alternate hypothesis is that oral sex inoculates and establishes gastrointestinal tract infection. Distinguishing these hypotheses is difficult in women. In men, autoinoculation is unlikely and heterosexual men frequently perform oral sex, but rarely participate in receptive anal exposure behaviors. METHODS: We enrolled high-risk men with and without nongonococcal urethritis who presented to a sexually transmitted infection clinic in Indianapolis, Indiana. Urine and rectal swabs were collected and tested for urogenital and rectal CT, Neisseria gonorrhoeae (NG), and Mycoplasma genitalium (MG). Men completed surveys concerning symptoms, sexual orientation, and detailed recent and lifetime oral and anal sexual behaviors. RESULTS: Rectal CT was detected in 2/84 (2.4%) heterosexual men who reported cunnilingus, but no lifetime receptive anal behaviors. All of the men who denied receptive anal behaviors were negative for rectal NG and MG. In homosexual and bisexual men, rectal CT prevalence was high (9.7%), and rectal NG (4.8%) and MG (4.8%) were also detected. CONCLUSIONS: We detected rectal CT infections in heterosexual men who reported cunnilingus but denied receptive anal behaviors. Oral sex may be a risk factor for rectal CT infection via oral inoculation of the gastrointestinal tract.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/isolamento & purificação , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Adulto , Idoso , Canal Anal/microbiologia , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/microbiologia , Heterossexualidade , Humanos , Indiana/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Reto/microbiologia , Fatores de Risco , Infecções Sexualmente Transmissíveis/microbiologia , Inquéritos e Questionários , Adulto Jovem
13.
Phytopathology ; 109(3): 436-445, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30256185

RESUMO

Early blight, caused by Alternaria solani, along with brown spot, caused by A. alternata, have the potential to reduce quality and yield in potato production globally. Prior to this study, the incidence, disease impact, and fungicide resistance attributes of A. alternata in Wisconsin were poorly understood. Potato pathogens were isolated from foliar lesions at three commercial locations in Wisconsin in 2012 and 2017 and were initially morphologically identified as A. solani (n = 33) and A. alternata (n = 40). Identifications were further corroborated with the phylogenetic analysis of the internal transcribed spacer (ITS), translation elongation factor 1 (TEF1), gapdh, Alt a 1, and OPA10-2. A multigene phylogeny of ITS, TEF1, gapdh, and Alt a 1 showed five genotypes of A. alternata and one single genotype of A. solani. We demonstrated that the A. alternata isolates were virulent on potato cultivars Russet Burbank (P < 0.013) and Atlantic (P < 0.0073), though they caused less disease than A. solani (P < 0.0001 and P < 0.0001, respectively). A. alternata caused little disease on the breeding line 24-24-12 (P = 0.9929), and A. solani caused fewer disease symptoms on 24-24-12 than on Russet Burbank (P < 0.0001) or Atlantic (P < 0.0001). Breeding line 24-24-12 may be a promising source of potential resistance for the two diseases. There was no significant difference in virulence of different A. alternata genotypes, and no significant difference in virulence or genotype clustering among isolates from the three locations. Isolates of A. alternata that induced chlorosis caused larger lesion areas than isolates that did not in Russet Burbank (P < 0.0001), Atlantic (P < 0.0001), and 24-24-12 (P = 0.0365). There was no significant difference in virulence between quinone outside inhibitor (QoI)-sensitive and QoI-resistant isolates of A. alternata. This study enhanced our understanding of potato early blight and brown spot in Wisconsin, and suggested that A. alternata in addition to A. solani should be carefully monitored and possibly uniquely managed in order to achieve overall disease control.


Assuntos
Alternaria , Doenças das Plantas/microbiologia , Solanum tuberosum , Alternaria/genética , Alternaria/crescimento & desenvolvimento , Filogenia , Virulência , Wisconsin
14.
Sex Transm Dis ; 45(7): e40-e42, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29465655

RESUMO

To evaluate self-reported symptoms to guide urethritis diagnosis, symptomatic men being evaluated for urethritis were asked about 7 symptoms captured during history taking. Discharge and dysuria were significantly associated with urethritis and, when combined with genital irritation and itching, identified 95% of urethritis cases; odor and urinary frequency performed poorly.


Assuntos
Autorrelato , Uretrite/diagnóstico , Adulto , Idoso , Infecções por Chlamydia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes , Prurido/etiologia , Inquéritos e Questionários , Uretra/microbiologia , Uretra/patologia , Uretrite/microbiologia , Adulto Jovem
15.
J Infect Dis ; 215(12): 1888-1892, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28520912

RESUMO

Chlamydiatrachomatis (Ct) infection causes significant morbidity. In vitro studies demonstrate that Ct growth inhibition occurs by interferon-gamma (IFN-γ)-mediated depletion of intracellular tryptophan, and some Ct strains utilize extracellular indole to restore tryptophan levels. Whether tryptophan levels are associated with Ct infection clearance in humans remains unknown. We evaluated tryptophan, indole, and IFN-γ levels in cervicovaginal lavages from women with either naturally cleared or persisting Ct infection. Women who cleared infection had significantly lower tryptophan levels and trended toward lower IFN-γ levels compared to women with persisting infection. Due to its volatility, indole was not measurable in either group.


Assuntos
Infecções por Chlamydia/tratamento farmacológico , Chlamydia trachomatis/imunologia , Interferon gama/análise , Triptofano/análise , Adolescente , Adulto , Azitromicina/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Ducha Vaginal , Adulto Jovem
16.
J Infect Dis ; 215(11): 1653-1656, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28444306

RESUMO

Chlamydia trachomatis elementary body enzyme-linked immunosorbent assay (ELISA) was used to investigate serum anti-CT immunoglobulin G1 (IgG1; long-lived response) and immunoglobulin G3 (IgG3; short-lived response indicating more recent infection) from treatment (enrollment) and 6-month follow-up visits in 77 women previously classified as having spontaneous resolution of chlamydia. Of these women, 71.4% were IgG1+IgG3+, consistent with more recent chlamydia resolution. 15.6% were IgG3- at both visits, suggesting absence of recent chlamydia. Using elementary body ELISA, we demonstrated approximately 1 in 6 women classified as having spontaneous resolution of chlamydia might have been exposed to C. trachomatis but not infected. Further, we classified their possible infection stage.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Imunoglobulina G/sangue , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Adulto Jovem
17.
J Clin Microbiol ; 55(7): 2249-2254, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28490486

RESUMO

Urethral swabs are the samples of choice for point-of-care Gram stain testing to diagnose Neisseria gonorrhoeae infection and nongonococcal urethritis (NGU) in men. As an alternative to urethral swabs, meatal swabs have been recommended for the collection of urethral discharge to diagnose N. gonorrhoeae and Chlamydia trachomatis infection in certain populations by nucleic acid amplification testing (NAAT), as they involve a less invasive collection method. However, as meatal swabs could be sampling a reduced surface area and result in fewer collected epithelial cells compared to urethral swabs, the adequacy of meatal swab specimens to collect sufficient cellular material for Gram stain testing remains unknown. We enrolled 66 men who underwent either urethral or meatal swabbing and compared the cellular content and Gram stain failure rate. We measured the difference in swab cellular content using the Cepheid Xpert CT/NG sample adequacy control crossing threshold (SACCT) and determined the failure rate of Gram stain smears (GSS) due to insufficient cellular material. In the absence of discharge, meatal smears were associated with a significant reduction in cellular content (P = 0.0118), which corresponded with a GSS failure rate significantly higher than that for urethral swabs (45% versus 3%, respectively; P < 0.0001). When discharge was present, there was no difference among results from urethral and meatal swabs. Therefore, if GSS testing is being considered for point-of-care diagnosis of N. gonorrhoeae infection or NGU in men, meatal swabs should be avoided in the absence of a visible discharge.


Assuntos
Infecções Bacterianas/diagnóstico , Técnicas Bacteriológicas/métodos , Chlamydia trachomatis/isolamento & purificação , Neisseria gonorrhoeae/isolamento & purificação , Manejo de Espécimes/métodos , Uretrite/diagnóstico , Adulto , Idoso , Violeta Genciana , Humanos , Masculino , Pessoa de Meia-Idade , Fenazinas , Coloração e Rotulagem/métodos , Adulto Jovem
18.
Sex Transm Dis ; 44(1): 67-68, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27898567

RESUMO

Chlamydia trachomatis/Neisseria gonorrhoeae assay performance in males is typically determined using post-swab urine, though pre-swab urine is used in practice. We collected swabs and urine from men and used the Cepheid Xpert® CT/NG sample adequacy control to determine the effect of swab collection on urine cellular content. No difference was observed.


Assuntos
Uretra/microbiologia , Urinálise/estatística & dados numéricos , Coleta de Urina/métodos , Urina/microbiologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Urinálise/métodos , Adulto Jovem
19.
Phys Rev Lett ; 117(12): 120501, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27689259

RESUMO

Two of the key properties of quantum physics are the no-signaling principle and the Grover search lower bound. That is, despite admitting stronger-than-classical correlations, quantum mechanics does not imply superluminal signaling, and despite a form of exponential parallelism, quantum mechanics does not imply polynomial-time brute force solution of NP-complete problems. Here, we investigate the degree to which these two properties are connected. We examine four classes of deviations from quantum mechanics, for which we draw inspiration from the literature on the black hole information paradox. We show that in these models, the physical resources required to send a superluminal signal scale polynomially with the resources needed to speed up Grover's algorithm. Hence the no-signaling principle is equivalent to the inability to solve NP-hard problems efficiently by brute force within the classes of theories analyzed.

20.
Plant Dis ; 99(5): 641-647, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-30699690

RESUMO

Late blight, caused by Phytophthora infestans, is one of the most economically important diseases of potato and tomato worldwide. Repeated preventative application of fungicides is the primary means of control on susceptible solanaceous host crops. For organic production, fungicide choices are limited, and little efficacy data on noncopper options is available on which to base control recommendations. Twelve fungicides, including organic and conventional selections, were evaluated for both preventative and postinfection control of a single infection cycle of late blight caused by isolates representing three recently identified P. infestans clonal lineages (US-22, US-23, and US-24) using a detached tomato leaf assay. A subset of the most effective fungicides was also tested for preventative control of a single infection cycle of late blight caused by an isolate of US-23 on potted whole tomato plants under laboratory conditions. Fungicide applications made 2 days after inoculation failed to significantly control late blight on detached leaves in all treatments, with the exception of Bravo Ultrex (US-23 only) and Phostrol (US-22 only). Preventative fungicide applications of Bravo Ultrex, Ridomil Gold SL, Revus, Zonix, and low and high rates of EF400 significantly controlled late blight caused by US-22, -23, and -24 isolates. Additionally, preventative application of Phostrol significantly controlled late blight caused by the US-22 isolate; and Phostrol, low rate of Mycostat, and high rate of Champ significantly controlled late blight caused by the US-23 isolate. Late blight caused by the US-24 isolate was significantly reduced compared with US-22 and US-23 isolates for all fungicide treatments applied after inoculation, as well as for all preventative fungicide treatments, with the exception of Bravo, Ridomil, and Revus. In whole-potted-plant assays with the US-23 isolate, late blight was significantly controlled by preventative application of Bravo Ultrex, Ridomil Gold SL, and high rate of EF400; disease was not significantly controlled by Zonix, low rate of EF400, Phostrol, or low and high rates of Champ. Based on these results, it is anticipated that currently available fungicides with suitability to conventional and organic systems can effectively control late blight caused by new clonal lineages of P. infestans when applied preventatively and that late blight caused by the US-24 clonal lineage may require less fungicide use than US-22 or US-23 to mitigate disease.

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