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1.
Int J STD AIDS ; 35(5): 379-388, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38166231

RESUMO

BACKGROUND: Men who have sex with men (MSM) are at risk for sexually transmitted infections (STIs), but more data on extragenital carriage are needed. AIM: We assessed the genital and extragenital prevalence of bacterial and other STIs in MSM in a Lisbon sexual health clinic. METHODS: We screened oral, anal, and urine samples of MSM visiting the GAT-CheckpointLX clinic June 2017-December 2021 for Chlamydia trachomatis (including lymphogranuloma venereum, LGV), Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, Mycoplasma hominis, Ureaplasma urealyticum, and U. parvum. Ano-oro-genital lesions were tested for LGV, Treponema pallidum, and Herpes Simplex Virus. Blood was tested for HIV and T. pallidum antibodies. RESULTS: N. gonorrhoeae was found in 16.6% of the MSM followed by C. trachomatis (13.2%), M. genitalium (10.3%) and T. vaginalis (0.2%). The most frequent occurrence was anorectal (C. trachomatis, M. genitalium) and oral (N. gonorrhoeae). We found high carriage of U. urealyticum (36.1%) and M. hominis (22.1%). LGV was detected in 21.8% of chlamydia-positive anorectal swabs. Syphilis was detected in 22.6% of tested MSM, while 13.8% had HIV. Gonorrhoea and chlamydia were significantly more prevalent in MSM with concomitant HIV or syphilis. CONCLUSION: The substantial extragenital prevalence of bacterial STIs in MSM, and HIV and syphilis coinfections, suggest screening has value in identifying hidden carriage and in contributing for providing better care.


Assuntos
Doenças do Ânus , Infecções por Chlamydia , Gonorreia , Infecções por HIV , Linfogranuloma Venéreo , Infecções por Mycoplasma , Mycoplasma genitalium , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Sífilis , Masculino , Humanos , Chlamydia trachomatis , Neisseria gonorrhoeae , Homossexualidade Masculina , Infecções por Mycoplasma/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Gonorreia/diagnóstico , Infecções por HIV/epidemiologia , Infecções por Chlamydia/diagnóstico , Prevalência
2.
Surg Endosc ; 38(1): 66-74, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37903884

RESUMO

BACKGROUND: The use of the laparoscopic approach for the treatment of carcinomatosis from epithelial ovarian cancer (EOC) is controversial. The aim of this study was to compare the short-term outcomes of both laparoscopic and open approach for interval CRS+HIPEC in a matched cohort of patients with advanced EOC. METHODS: A retrospective analysis of a prospectively maintained database including 254 patients treated with interval CRS-HIPEC between January 2016 and December 2021 was performed. Patients with primary disease and limited carcinomatosis (PCI ≤ 10) were selected. A comparative analysis of patients treated by either open (O-CRS-HIPEC) or the laparoscopic (L-CRS-HIPEC) approach was conducted. Overall survival (OS), disease-free survival (DFS), and perioperative outcomes were analysed. RESULTS: Fifty-three patients were finally selected and enrolled into two comparable groups in this study. Of these, 14 patients were treated by interval L-CRS-HIPEC and 39 by interval O-CRS-HIPEC. The L-CRS-HIPEC group had a shorter hospital stay (5.6 ± 1.9 vs. 9.7 ± 9.8 days; p < 0.001) and a shorter time to return to systemic chemotherapy (4.3 ± 1.9 vs. 10.3 ± 16.8 weeks; p = 0.003). There were no significant differences in postoperative complications between both groups. The 2-year OS and DFS was 100% and 62% in the L-CRS-HIPEC group versus 92% and 60% in the O-CRS-HIPEC group, respectively (p = 0.96; p = 0.786). CONCLUSION: This study suggests that the use of interval L-CRS-HIPEC for primary advanced EOC is associated with shorter hospital stay and return to systemic treatment while obtaining similar oncological results compared to the open approach. Further prospective research is needed to recommend this new approach for these strictly selected patients.


Assuntos
Carcinoma , Hipertermia Induzida , Laparoscopia , Neoplasias Ovarianas , Intervenção Coronária Percutânea , Neoplasias Peritoneais , Humanos , Feminino , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/cirurgia , Quimioterapia Intraperitoneal Hipertérmica , Neoplasias Peritoneais/tratamento farmacológico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Procedimentos Cirúrgicos de Citorredução/métodos , Hipertermia Induzida/métodos , Carcinoma/cirurgia , Neoplasias Ovarianas/cirurgia , Terapia Combinada , Taxa de Sobrevida
4.
Nanomaterials (Basel) ; 13(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37947697

RESUMO

The tribological performance of novel bio-based lubricating greases thickened with electrospun lignin nanostructures was investigated in a nanotribometer using a steel-steel ball-on-disc configuration. The impact of electrospun nanofibrous network morphology on friction and wear is explored in this work. Different lignin nanostructures were obtained with electrospinning using ethylcellulose or PVP as co-spinning polymers and subsequently used as thickeners in castor oil at concentrations of 10-30% wt. Friction and wear generally increased with thickener concentration. However, friction and wear decreased when using homogeneous bead-free nanofiber mats (with higher fiber diameter and lower porosity) rather than nanostructures dominated by the presence of particles or beaded fibers, which was favored by reducing the lignin:co-spinning polymer ratio.

5.
Artigo em Inglês | MEDLINE | ID: mdl-37835073

RESUMO

Mpox is a viral disease caused by the monkeypox virus, which marked the year of 2022 with a global outbreak. While previously considered to be a zoonosis of almost exclusive animal-to-human transmission, the current outbreak has been attributed to human-to-human transmission, particularly sexual transmission. As a new sexually transmissible disease, we studied the epidemiological and clinical features, as well as the concomitant occurrence of other sexually transmissible diseases, treatment approach, and outcome of our 291 patients, in the current outbreak. We found a total of 169 concomitant sexually transmissible infections of bacterial and viral origins, corresponding to 107 patients. Neisseria gonorrhoeae was the most common agent, particularly in the anal location. With this work, we emphasize the need for a thorough epidemiological and medical history, as well as a concomitant complete laboratorial screening for other STIs in patients with confirmed or suspected mpox.


Assuntos
Mpox , Animais , Humanos , Zoonoses , Instituições de Assistência Ambulatorial , Surtos de Doenças , Demografia
6.
Nat Med ; 29(10): 2509-2517, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696933

RESUMO

Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Masculino , Humanos , Portugal/epidemiologia , Homossexualidade Masculina , Surtos de Doenças , Análise por Conglomerados
7.
J Pers Med ; 13(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37511783

RESUMO

Sexually transmitted infections (STIs) constitute one of the leading causes of disease burden worldwide, leading to considerable morbidity, mortality, health expenditures, and stigma. Of note are the most common bacterial STIs, chlamydial and gonococcal infections, whose etiological agents are Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), respectively. Despite being usually asymptomatic, in some cases these infections can be associated with long-term severe complications, such as pelvic inflammatory disease, chronic pelvic pain, infertility, ectopic pregnancy, and increased risk of other STIs acquisition. As the symptoms, when present, are usually similar in both infections, and in most of the cases these infections co-occur, the dual-test strategy, searching for both pathogens, should be preferred. In line with this, herein we focus on the main aspects of CT and NG infections, the clinical symptoms as well as the appropriate state-of-the-art diagnostic tests and treatment. Cost-effective strategies for controlling CT and NG infections worldwide are addressed. The treatment for both infections is based on antibiotics. However, the continuing global rise in the incidence of these infections, concomitantly with the increased risk of antibiotics resistance, leads to difficulties in their control, particularly in the case of NG infections. We also discuss the potential mechanism of tumorigenesis related to CT infections. The molecular bases of CT and NG infections are addressed, as they should provide clues for control or eradication, through the development of new drugs and/or effective vaccines against these pathogens.

8.
Front Physiol ; 14: 1212031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492638

RESUMO

Introduction: Medical education should promote the development of skills and abilities that can be applied to real-world work performance. The aim of this study is to evaluate technical and methodological knowledge, as well as physician-patient communication skills, as one of the most important transversal competencies that a good physician should acquire; all this in a reliable, accurate and objective way. Methods: We present a rubric specifically designed and implemented for the evaluation of specific and transversal competencies in the physiology practical sessions, during the second year of the medical degree. The assessment consists in two evaluation tests: 1) a theoretical test that consists of multiple-choice questions. Students must demonstrate that they have acquired adequate theoretical knowledge (specific competency "to know"); 2) a practical test, in which students are evaluated by the rubric through the simulation of a medical consultation. Thus, demonstrating their ability to execute/apply what they have learned in class (specific competency "to know how to do"). They are also evaluated on the transversal competencies that we call "communication with the patient" (transversal competency "to know how to be there") and "dealing with the patient" (transversal competency "to know how to be"). Results: We evaluated whether there were differences in the grades obtained by students when the transversal competencies were not assessed (academic years 2017-2018 and 2018-2019; n = 289), and when the transversal competencies were assessed by applying the rubric in the academic years 2019-2020, 2021-2022, and 2022-2023 (n = 526). Furthermore, we present a student perception that supports the use of clinical simulation and our rubric as a good method within the competency learning process. Discussion: The acquisition of these competencies, starting from the first courses of undergraduate education, helps to raise the students' awareness in the development of a more humanized medicine, allowing a better response to the patients' needs. Our rubric, which clearly indicate the performance criteria, have become an excellent method to carry out the assessment of competencies, both for students and teachers, since they allow to obtain clear evidence of the level of acquisition and application of knowledge.

9.
Violence Vict ; 38(3): 358-374, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348958

RESUMO

Intimate partner violence (IPV) is an important public health problem. Female victims of IPV do not always use the institutional resources available to them. We conducted a cross-sectional study using data from the Spanish 2014 Macro-Survey on Violence Against Women. The findings show that 15% of the survey participants suffered from IPV in the last year. The factors associated with a higher probability of suffering IPV are being of non-Spanish nationality, being a student, having a low-educational level, having no income, being the household head, and not having a current partner. Regarding the resources used by women subjected to IPV, almost half resorted to informal sources, such as female friends and/or their own mothers. The use of formal resources was low. Therefore, IPV continues to be a problem in Spain that seems to remain in the private domain. Consequently, it is necessary to increase the availability of and access to legal resources.


Assuntos
Violência por Parceiro Íntimo , Humanos , Feminino , Espanha , Estudos Transversais , Mães , Renda , Prevalência , Fatores de Risco , Parceiros Sexuais
10.
Distúrb. comun ; 35(1): e59350, 01/06/2023.
Artigo em Português | LILACS | ID: biblio-1436316

RESUMO

Proposta recente de apresentação de Programa de Condicionamento Vocal e Respiratório (CVR I) incentivou a continuidade (CVR II), considerando novas estratégias de treinamento muscular vocal e respiratório que pudessem contribuir para melhor desempenho de profissionais da voz. Para a condução da ação, mais uma vez, houve a participação integrada de fonoaudiólogos e fisioterapeutas e, no papel de participantes, profissionais da voz. Planejada para dez encontros, em que dois deles (início e fim) foram destinados à coleta de dados, a proposta teve como objetivo aumentar ainda mais a resistência vocal e respiratória dos participantes, promovendo melhor rendimento profissional. Exercícios de trato vocal semiocluído e respiratórios foram realizados com o uso dos incentivadores denominados New Shaker® e Respiron Athletic 2®. Trata-se de mais uma experiência relatada na direção de convocar outros profissionais a colocarem em prática ações para o condicionamento vocal e respiratório de profissionais da voz. O uso de incentivadores respiratórios e a parceria com a Fisioterapia são apresentados e recomendados para melhor entendimento e consequente atendimento das questões da voz e da respiração. (AU)


This is a continuation (VRC II) of a recent proposal to present a Vocal and Respiratory Conditioning (VRC I) Program using new vocal and respiratory muscle training strategies aimed at contributing to a better performance of voice professionals. Once again, the initiative included the integrated participation of speech-language pathologists and physiotherapists, as well as voice professionals as participants. Ten meetings were planned in the initial proposal, with the first and last meeting focused on data collection, the proposal aimed to further increase the vocal and respiratory resistance of the participants, promoting better professional performance. Semi-occluded vocal tract and respiratory exercises were performed with using the New Shaker® and Respiron Athletic 2® boosters. This is an experience reported in order to encourage other professionals to put into practice actions for vocal and respiratory conditioning. The use of respiratory boosters and the partnership with Physiotherapy are recommended, aiming at a better understanding and consequent care of voice and breathing issues in voice professionals. (AU)


Una propuesta reciente de presentar un Programa de Acondicionamiento Vocal y Respiratório (CVR I) fomentó la continuidad (CVR II), considerando nuevas estratégias para el entrenamiento de los músculos vocales y respiratórios que podrían contribuir a un major desempeño de los profesionales de la voz. Para conducir la acción, una vez más, se contó con la participación integrada de fonoaudiológos y kinesiológos, y en el papel de participantes, profesionales de la voz. Planificada para diez encuentros, en los que dos de ellos (inicio y final) están destinados a la recolección de datos, la propuesta tiene como objetivo aumentar aún más la resistência vocal y respiratoria de los participantes, promoviendo un mejor desempeño profesional. Se realizaron ejercicios de tracto vocal y respiratorio semiocluidos con el uso de incentivos denominados New Shaker® y Respiron Athletic 2®. Esta es una experiencia más reportada en la dirección de invitar a otros profesionales a poner en práctica acciones para el acondicionamiento vocal y respiratório de los profesionales de la voz. Se presenta y recomienda el uso de soportes respiratórios y la asociación con Kinesiología para una mejor comprensión y consecuente atención de problemas de voz y respiración. (AU)


Assuntos
Humanos , Masculino , Adulto , Fonoterapia/métodos , Exercícios Respiratórios/métodos , Desempenho Profissional , Qualidade da Voz , Treinamento da Voz , Modalidades de Fisioterapia , Fonoaudiologia , Treino Aeróbico
11.
BMC Nurs ; 22(1): 149, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37143072

RESUMO

BACKGROUND: Falls are among the most common and serious adverse events for hospitalised patients. In-hospital falls pose a major medical and economic challenge for public health worldwide. Nevertheless, the issue is often addressed without regard to certain relevant variables such as the time of the fall. The aim of this study was to determine the effect of the implementation of a nurse-led intervention based on the temporal patterns of falls and their aetiology on the occurrence of falls. METHODS: A mixed-method research design was carried out in three phases: a) a longitudinal prospective study (audits, chronobiological analyses and implementation of a multicentre nurse-led intervention based on temporal patterns of falls); b) a retrospective study of fall records; and c) a qualitative study based on focus groups. The protocol was published in 2021. RESULTS: A difference was observed in the number of fall records before and after the chronopreventive intervention (retrospective: 64.4% vs. 35.6%; p < 0,001). According to the interrupted series analysis, considering the influence of the COVID-19 pandemic, a reduction in falls of 2.96% (95% CI 1.70%-4.17%) was observed. The concepts of falls, the COVID-19 pandemic and the causes of non-registration have emerged as categories for qualitative analysis. CONCLUSIONS: A multicentric nurse-led program based on tailored organisational, educational and behavioural chronopreventive measures seems to lead to a reduction in the number of in-hospital falls. The findings of the present study, highlighting the implementation of chronopreventive measures, can serve as a basis for future health policies. TRIAL REGISTRATION: The project was registered on the Clinical Trials Registry NCT04367298 (29/04/2020).

12.
Langenbecks Arch Surg ; 408(1): 146, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046100

RESUMO

PURPOSE: The benefits of the minimally invasive approach for performing cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy (L-CRS + HIPEC) have been described previously, associating an early recovery with similar oncologic outcomes in patients with limited peritoneal carcinomatosis. Currently, no studies are focusing on the learning curve for this emerging procedure. This study aimed to evaluate the L-CRS + HIPEC learning curve and its knock-on effect on the perioperative outcomes. METHODS: We identified all consecutive unselected patients who underwent L-CRS + HIPEC by a single surgeon between April 2016 and January 2022 (n = 51). Patients who underwent risk-reducing CRS + HIPEC (PCI = 0) or initial conversion due to an intraoperative PCI > 10 were excluded from the final analysis. To evaluate the learning curve, perioperative data were analysed using the cumulative sum (CUSUM) analysis. RESULTS: Twenty-six patients were included in the final analysis. Major morbidity occurred in one patient (3.8%). The difficulty of the L-CRS + HIPEC procedures was categorised as low in 23.1% (n = 6), intermediate in 19.2% (n = 5), and advanced in 57.7% (n = 15). The mean length of hospital stay was 5.4 ± 1.5 days. No patient had a conversion to open surgery. The learning curve was divided into two distinct phases: the learning phase (1-14) and the consolidation phase (15-26). A significant decrease in the operative time (375 ± 103.1 vs 239.2 ± 63.6 min) was observed with no differences in complexity, the number of peritonectomy procedures, or morbidity. CONCLUSION: L-CRS + HIPEC is a complex procedure that must be performed in a high-volume and experienced oncologic unit, requiring a learning curve to achieve the consolidation condition, which could be established after 14 procedures.


Assuntos
Hipertermia Induzida , Intervenção Coronária Percutânea , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Curva de Aprendizado , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Retrospectivos , Terapia Combinada , Taxa de Sobrevida
13.
Artigo em Inglês | MEDLINE | ID: mdl-36767143

RESUMO

(1) Background: The rate of cesarean sections in late fetal mortality remains high. We aimed to determine the prevalence of late fetal mortality in Spain and risk factors for cesarean birth in women with stillbirth ≥ 28 weeks gestation between 2016-2019. (2) Methods: A retrospective observational study with national data between 2016-2019. A total of 3504 births with fetal dead were included. Sociodemographic, obstetrical and neonatal variables were analyzed using univariate and multivariate logistic regression (MLR), with cesarean birth with a stillborn ≥ 28 weeks gestation as the dependent variable. (3) Results: The late fetal mortality rate was 2.8 × 1000; 22.7% of births were by cesarean section. Factors associated with cesarean were having a multiple birth (aOR 6.78); stillbirth weight (aOR 2.41); birth taking place in towns with over 50,000 inhabitants (aOR 1.34); and mother's age ≥ 35 (aOR 1.23). (4) Conclusions: The late fetal mortality rate increased during the period. The performance of cesarean sections was associated with the mother's age, obstetric factors and place of birth. Our findings encourage reflection on how to best put into practice national clinical and socio-educational prevention strategies, as well as the approved protocols on how childbirth should be correctly conducted.


Assuntos
Cesárea , Natimorto , Recém-Nascido , Gravidez , Feminino , Humanos , Natimorto/epidemiologia , Mortalidade Fetal , Espanha/epidemiologia , Prevalência
17.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 1-8, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495527

RESUMO

A comparative overview of the global gene expression levels of S. agalactiae reference strain NEM316 at the exponential growth phase was done through RNA-sequencing. The expression levels of 47 genes potentially linked to virulence evidenced that: i) the major nuclease, GBS_RS03720/gbs0661, presented higher mean expression values than the remainder of DNase genes; ii) the genetic pilus island PI-2a genes presented higher mean expression values than PI-1 coding genes; and, iii) three virulence-associated genes ranked among the top-100 most expressed genes (GBS_RS07760, GBS_RS09445 and GBS_RS03485). Among this top-100, genes encoding proteins involved in "Translation, ribosomal structure and biogenesis" represented 46%. Curiously, genes with no assigned function were grouped in the category of highly expressed genes. As very little is known about the molecular mechanisms behind the release of DNases, preliminary assays were developed to understand whether direct DNA exposure would affect gene expression at the exponential growth phase. No differentially expressed genes were detected, indicating that follow-up studies are needed to disclose the complex molecular pathways (and stimuli) triggering the release of DNases. In general, our insights on the global expression levels of NEM316 at exponential growth phase with and without DNA exposure should open novel research lines to decipher S. agalactiae puzzling adaptation and virulence mechanisms, such as DNase production.


Assuntos
Infecções Estreptocócicas , Streptococcus agalactiae , Humanos , Streptococcus agalactiae/genética , Streptococcus agalactiae/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Virulência/genética , Perfilação da Expressão Gênica , Infecções Estreptocócicas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
18.
Polymers (Basel) ; 14(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36365734

RESUMO

This study reports on a novel strategy for manufacturing thickened gel-like castor oil formulations by dispersing electrospun lignin/ethylcellulose nanostructures. These thickened formulations were rheologically and tribologically evaluated with the aim of being proposed as alternative ecofriendly lubricating greases. Low-sulfonate kraft lignin (LSL) and ethylcellulose (EC) were dissolved in a DMAc:THF mixture at different concentrations (8, 10, and 15 wt.%) and LSL:EC ratios (50:50, 70:30, and 90:10) and subjected to electrospinning. The resulting electrospun nanostructures were morphologically characterized. EC acting as the cospinning polymer improved both LSL spinnability and the oil structuring ability. Solutions with a high lignin content achieved microsized particles connected by fibrils, whereas solutions with a high EC content (50:50 ratio) and LSL/EC total concentration (10 and 15 wt.%) yielded beaded or bead-free nanofibers, due to enhanced extensional viscoelastic properties and nonNewtonian characteristics. The gel-like properties of electrospun nanostructure dispersions in castor oil were strengthened with the nanostructure concentration and the EC:LSL ratio, as a result of the formation of a more interconnected fiber network. The oleodispersions studied exhibited a satisfactory frictional response in a tribological contact, with friction coefficient values that were comparable to those achieved with traditional lithium-lubricating greases.

20.
Front Cell Infect Microbiol ; 12: 902210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903198

RESUMO

Chlamydia trachomatis is an obligate intracellular bacterium causing ocular and urogenital infections in humans that are a significant burden worldwide. The completion of its characteristic infectious cycle relies on the manipulation of several host cell processes by numerous chlamydial type III secretion effector proteins. We previously identified the C. trachomatis CteG effector and showed it localizes at the host cell plasma membrane at late stages of infection. Here, we showed that, from 48 h post-infection, mammalian cells infected by wild-type C. trachomatis contained more infectious chlamydiae in the culture supernatant than cells infected by a CteG-deficient strain. This phenotype was CteG-dependent as it could be complemented in cells infected by the CteG-deficient strain carrying a plasmid encoding CteG. Furthermore, we detected a CteG-dependent defect on host cell cytotoxicity, indicating that CteG mediates chlamydial lytic exit. Previous studies showed that Pgp4, a global regulator of transcription encoded in the C. trachomatis virulence plasmid, also mediates chlamydial lytic exit. However, by using C. trachomatis strains encoding or lacking Pgp4, we showed that production and localization of CteG are not regulated by Pgp4. A C. trachomatis strain lacking both CteG and Pgp4 was as defective in promoting host cell cytotoxicity as mutant strains lacking only CteG or Pgp4. Furthermore, CteG overproduction in a plasmid suppressed the host cell cytotoxic defect of CteG- and Pgp4-deficient chlamydiae. Overall, we revealed the first chlamydial type III secretion effector involved in host cell lytic exit. Our data indicates that CteG and Pgp4 participate in a single cascade of events, but involving multiple layers of regulation, leading to lysis of host cells and release of the infectious chlamydiae.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Chlamydia/microbiologia , Células HeLa , Humanos , Mamíferos/genética , Plasmídeos/genética
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