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1.
Fluids Barriers CNS ; 21(1): 53, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956598

RESUMO

AQP4 is expressed in the endfeet membranes of subpial and perivascular astrocytes and in the ependymal cells that line the ventricular system. The sporadic appearance of obstructive congenital hydrocephalus (OCHC) has been observed in the offspring of AQP4-/- mice (KO) due to stenosis of Silvio's aqueduct. Here, we explore whether the lack of AQP4 expression leads to abnormal development of ependymal cells in the aqueduct of mice. We compared periaqueductal samples from wild-type and KO mice. The microarray-based transcriptome analysis reflected a large number of genes with differential expression (809). Gene sets (GS) associated with ependymal development, ciliary function and the immune system were specially modified qPCR confirmed reduced expression in the KO mice genes: (i) coding for transcription factors for ependymal differentiation (Rfx4 and FoxJ1), (ii) involved in the constitution of the central apparatus of the axoneme (Spag16 and Hydin), (iii) associated with ciliary assembly (Cfap43, Cfap69 and Ccdc170), and (iv) involved in intercellular junction complexes of the ependyma (Cdhr4). By contrast, genes such as Spp1, Gpnmb, Itgax, and Cd68, associated with a Cd11c-positive microglial population, were overexpressed in the KO mice. Electron microscopy and Immunofluorescence of vimentin and γ-tubulin revealed a disorganized ependyma in the KO mice, with changes in the intercellular complex union, unevenly orientated cilia, and variations in the planar cell polarity of the apical membrane. These structural alterations translate into reduced cilia beat frequency, which might alter cerebrospinal fluid movement. The presence of CD11c + microglia cells in the periaqueductal zone of mice during the first postnatal week is a novel finding. In AQP4-/- mice, these cells remain present around the aqueduct for an extended period, showing peak expression at P11. We propose that these cells play an important role in the normal development of the ependyma and that their overexpression in KO mice is crucial to reduce ependyma abnormalities that could otherwise contribute to the development of obstructive hydrocephalus.


Assuntos
Aquaporina 4 , Epêndima , Hidrocefalia , Camundongos Knockout , Microglia , Animais , Epêndima/metabolismo , Epêndima/patologia , Hidrocefalia/metabolismo , Hidrocefalia/genética , Hidrocefalia/patologia , Microglia/metabolismo , Aquaporina 4/metabolismo , Aquaporina 4/genética , Camundongos , Aqueduto do Mesencéfalo/metabolismo , Aqueduto do Mesencéfalo/patologia , Antígenos CD11/metabolismo , Antígenos CD11/genética , Camundongos Endogâmicos C57BL
2.
Clin Neurol Neurosurg ; 242: 108353, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38830290

RESUMO

OBJECTIVES: This study aims to describe resting state networks (RSN) in patients with disorders of consciousness (DOC)s after acute severe traumatic brain injury (TBI). METHODS: Adult patients with TBI with a GCS score <8 who remained in a coma, minimally conscious state (MCS), or unresponsive wakefulness syndrome (UWS), between 2017 and 2020 were included. Blood-oxygen-level dependent imaging was performed to compare their RSN with 10 healthy volunteers. RESULTS: Of a total of 293 patients evaluated, only 13 patients were included according to inclusion criteria: 7 in coma (54%), 2 in MCS (15%), and 4 (31%) had an UWS. RSN analysis showed that the default mode network (DMN) was present and symmetric in 6 patients (46%), absent in 1 (8%), and asymmetric in 6 (46%). The executive control network (ECN) was present in all patients but was asymmetric in 3 (23%). The right ECN was absent in 2 patients (15%) and the left ECN in 1 (7%). The medial visual network was present in 11 (85%) patients. Finally, the cerebellar network was symmetric in 8 patients (62%), asymmetric in 1 (8%), and absent in 4 (30%). CONCLUSIONS: A substantial impairment in activation of RSN is demonstrated in patients with DOC after severe TBI in comparison with healthy subjects. Three patterns of activation were found: normal/complete activation, 2) asymmetric activation or partially absent, and 3) absent activation.


Assuntos
Lesões Encefálicas Traumáticas , Transtornos da Consciência , Humanos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Transtornos da Consciência/fisiopatologia , Transtornos da Consciência/etiologia , Transtornos da Consciência/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Imageamento por Ressonância Magnética , Idoso , Adulto Jovem , Descanso/fisiologia , Estado Vegetativo Persistente/fisiopatologia , Estado Vegetativo Persistente/diagnóstico por imagem , Estado Vegetativo Persistente/etiologia
3.
J Thromb Haemost ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897386

RESUMO

BACKGROUND: Pediatric patients with acute lymphoblastic leukemia (ALL) are at highest risk of venous thromboembolism (VTE) during the induction phase of treatment (IT). These events are not predictable by conventional coagulation assays. OBJECTIVES: To investigate the utility of global coagulation assays (GCA) for assessing the hemostatic state in children with ALL during IT. METHODS: We included children with ALL (n=15) and healthy controls (n=15). Analyses were performed at different time points during IT of the AIEOP-BFM protocols. In addition to prothrombotic biomarkers, natural anticoagulants proteins and in vivo thrombin generation (TG) markers, ex vivo TG was measured using the gold-standard Calibrated-Automated-Thrombogram method (CAT), the automated-ST Genesia (STG), and Thrombodynamics-analyzer (TD). The latter also provided measurement of fibrin clot formation (FCF). RESULTS: Differently from conventional coagulation assays and in vivo TG markers, ex vivo GCA, detected increasing prothrombotic changes during IT. Particularly, TG measured with TD as expressed by endogenous thrombin potential (ETP) was significantly elevated already at d8-12 (p<0.01) and continued to increase during IT as compared to prior to treatment beginning, indicating a very early shift towards a procoagulant state. A similar pattern was observed for the rate of FCF (V:p<0.01 at d8-12). Remarkably, in patients developing thrombotic complications (n=5), both GCA, STG and TD, showed a significantly higher ETP very early (already at d8-12, p<0.05), well before clinical manifestation. CONCLUSION: GCA capture prothrombotic changes early during IT in ALL pediatric patients. If confirmed, this approach will allow tailoring thromboprophylaxis in children with ALL at highest risk for VTE.

4.
Neurol Clin ; 42(3): 717-738, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38937038

RESUMO

Neuroendovascular rescue of patients with acute ischemic stroke caused by a large arterial occlusion has evolved throughout the first quarter of the present century, and continues to do so. Starting with the intra-arterial instillation of thrombolytic agents via microcatheters to dissolve occluding thromboembolic material, the current status is one that includes a variety of different techniques such as direct aspiration of thrombus, removal by stent retriever, adjuvant techniques such as balloon angioplasty, stenting, and tactical intra-arterial instillation of thrombolytic agents in smaller branches to treat no-reflow phenomenon. The results have been consistently shown to benefit these patients, irrespective of whether they had already received intravenous tissue-type plasminogen activator or not. Improved imaging methods of patient selection and tactically optimized periprocedural care measures complement this dimension of the practice of neurointervention.


Assuntos
Procedimentos Endovasculares , Humanos , Procedimentos Endovasculares/métodos , Procedimentos Endovasculares/tendências , Acidente Vascular Cerebral/terapia , AVC Isquêmico/terapia , AVC Isquêmico/cirurgia , Terapia Trombolítica/métodos , Terapia Trombolítica/tendências
6.
Front Med (Lausanne) ; 11: 1322759, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721353

RESUMO

Introduction: Dental public health professionals play a critical role in preventing and controlling oral diseases. The purpose of this study was to assess the application of public health principles learned in a pediatric dentistry Master of Public Health (MPH) dual degree program to professional practice upon graduation. Methods: Semi-structured interviews were conducted with pediatric dentistry/MPH dual degree alumni who graduated from the program between 2012 and 2023. Interview questions inquired about characteristics of patient population, location of providers' clinic/organization, whether the program was worthwhile to their practice and application of principles learned in the program to their professional practice. Results: Twenty of the 22 program alumni agreed to be interviewed. All alumni thought the program was extremely worthwhile to their practice. They felt the MPH component of the program gave them the public health background and tools they needed to provide comprehensive and holistic care to their patients. Additionally, all alumni reported applying the public health principles they learned in the program to their professional practice through leadership roles, research and teaching that focuses on oral disease prevention and the promotion of dental health. Discussion: Given the importance of a dental public health professionals' role in reducing oral health disparities at the population level, more pediatric dentistry MPH dual degree programs are urgently needed. Additionally, more research is necessary to demonstrate the effectiveness of these programs, which will be critical to helping ensure the value of a dual degree in dentistry and public health is recognized and promoted worldwide.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38791758

RESUMO

Children living in rural and migrant areas in the United States disproportionately suffer from poor oral health. Additionally, there continues to be a shortage of pediatric dentists practicing in rural/migrant areas. The purpose of this formative research study was to assess whether staff, teachers and families from rural/migrant Head Start/Early Head Start (HS/EHS) programs in California were receptive to oral health online education workshops conducted by pediatric dental residents who were assisted by bilingual (English and Spanish) community oral health workers (COHWs). Our findings suggest that partnering pediatric dental residents with bilingual COHWs to educate HS/EHS teachers, staff and parents on oral health care in rural/migrant areas could result in a rewarding experience for pediatric dentists that might lead them to practice in these communities upon graduation from their residency program. Furthermore, the positive feedback received from the teachers, staff and parents who participated in the workshops indicates they were receptive to receiving oral health information related to oral health literacy from the dental providers and COHWs. COHWs can help increase access to oral health care by serving as a bridge between families and providers by relaying information in a cultural, linguistic and sensitive manner.


Assuntos
Saúde Bucal , População Rural , Migrantes , Humanos , Saúde Bucal/educação , Educação a Distância/métodos , Intervenção Educacional Precoce , Estados Unidos , California , Pré-Escolar , Criança
8.
Med. intensiva (Madr., Ed. impr.) ; 48(4): 200-210, abr. 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-231955

RESUMO

Objective To explore combined non-invasive-respiratory-support (NIRS) patterns, reasons for NIRS switching, and their potential impact on clinical outcomes in acute-hypoxemic-respiratory-failure (AHRF) patients. Design Retrospective, single-center observational study. Setting Intensive Care Medicine. Patients AHRF patients (cardiac origin and respiratory acidosis excluded) underwent combined NIRS therapies such as non-invasive-ventilation (NIV) and High-Flow-Nasal-Cannula (HFNC). Interventions Patients were classified based on the first NIRS switch performed (HFNC-to-NIV or NIV-to-HFNC), and further specific NIRS switching strategies (NIV trial-like vs. Non-NIV trial-like and single vs. multiples switches) were independently evaluated. Main variables of interest Reasons for switching, NIRS failure and mortality rates. Results A total of 63 patients with AHRF were included, receiving combined NIRS, 58.7% classified in the HFNC-to-NIV group and 41.3% in the NIV-to-HFNC group. Reason for switching from HFNC to NIV was AHRF worsening (100%), while from NIV to HFNC was respiratory improvement (76.9%). NIRS failure rates were higher in the HFNC-to-NIV than in NIV-to-HFNC group (81% vs. 35%, p < 0.001). Among HFNC-to-NIV patients, there was no difference in the failure rate between the NIV trial-like and non-NIV trial-like groups (86% vs. 78%, p = 0.575) but the mortality rate was significantly lower in NIV trial-like group (14% vs. 52%, p = 0.02). Among NIV to HFNC patients, NIV failure was lower in the single switch group compared to the multiple switches group (15% vs. 53%, p = 0.039), with a shorter length of stay (5 [2–8] vs. 12 [8–30] days, p = 0.001). Conclusions NIRS combination is used in real life and both switches’ strategies, HFNC to NIV and NIV to HFNC, are common in AHRF management. Transitioning from HFNC to NIV is suggested as a therapeutic escalation and in this context performance of a NIV-trial could be beneficial. ... (AU)


Objetivo Explorar los patrones combinados de soporte-respiratorio-no-invasivo (SRNI), las razones para cambiar de SRNI y su potencial impacto en los resultados clínicos en pacientes con insuficiencia-respiratoria-aguda-hipoxémica (IRAH). Diseño Estudio observacional retrospectivo unicéntrico. Ámbito Cuidados Intensivos. Pacientes Pacientes con IRAH (excluyendo causa cardíaca y acidosis respiratoria) que recibieron tanto ventilación-no-invasiva (VNI) como cánula-nasal-de-alto-flujo (CNAF). Intervenciones Se categorizó a los pacientes según el primer cambio de SRNI realizado (CNAF-to-VNI o VNI-to-CNAF) y se evaluaron estrategias específicas de SRNI (VNI trial-like vs. Non-VNI trial-like y cambio único vs. múltiples cambios de NIRS) de manera independiente. Variables de interés principales Razones para el cambio, así como las tasas de fracaso de SRNI y la mortalidad. Resultados Un total de 63 pacientes recibieron SRNI combinado, 58,7% clasificados en el grupo CNAF-to-VNI y 41,3% en el grupo VNI-to-CNAF. Los cambios de CNAF a VNI ocurrieron por empeoramiento de la IRHA (100%) y de VNI a CNAF por mejora respiratoria (76.9%). Las tasas de fracaso de SRNI fueron mayores de CNAF a VNI que de VNI a CNAF (81% vs. 35%, p < 0.001). Dentro de los pacientes de CNAF a VNI, no hubo diferencia en las tasas de fracaso entre los grupos VNI trial-like y no-VNI trial-like (86% vs. 78%, p = 0.575), pero la mortalidad fue menor en el grupo VNI trial-like (14% vs. 52%, p = 0.02). Dentro de los pacientes de VNI a CNAF, el fracaso de VNI fue menor en grupo de cambio único vs. múltiple (15% vs. 53%, p = 0.039). Conclusiones Los cambios de estrategia de SRNI son comunes en el manejo clínico diario de la IRHA. El cambio de CNAF a VNI impresiona de ser una escalada terapéutica y en este contexto la realización de un VNI-trial puede ser beneficioso. Al contrario, cambiar de VNI a CNAF impresiona de ser una desescalada terapéutica y parece segura si no hay fracaso ... (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Insuficiência Respiratória/terapia , Dispositivos de Proteção Respiratória , Mecânica Respiratória , Suporte Ventilatório Interativo , Tratamento Conservador/instrumentação , Tratamento Conservador/métodos , Estudos Retrospectivos , Pneumonia , Síndrome do Desconforto Respiratório do Recém-Nascido
9.
Healthcare (Basel) ; 12(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38667620

RESUMO

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant demyelinating neuropathy characterized by an increased susceptibility to peripheral nerve injury from trauma, compression, or shear forces. Patients with this condition are unique, necessitating distinct considerations for anesthesia and surgical teams. This review describes the etiology, prevalence, clinical presentation, and management of HNPP and presents contemporary evidence and recommendations for optimal care for HNPP patients in the perioperative period. While the incidence of HNPP is reported at 7-16:100,000, this figure may be an underestimation due to underdiagnosis, further complicating medicolegal issues. With the subtle nature of symptoms associated with HNPP, patients with this condition may remain unrecognized during the perioperative period, posing significant risks. Several aspects of caring for this population, including anesthetic choices, intraoperative positioning, and monitoring strategy, may deviate from standard practices. As such, a tailored approach to caring for this unique population, coupled with meticulous preoperative planning, is crucial and requires a multidisciplinary approach.

10.
Front Oral Health ; 5: 1362647, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645574

RESUMO

Background: There is no accessible information on countries with oral health policies. The purpose of this study was to identify World Dental Federation (FDI) member countries with oral health policies and their scope and extent of coverage of oral health care for young children. Methods: This international survey recruited chief dental officers, oral health advisors to national ministries of health, and other key informants of the 158 FDI member countries between December 2020 and December 2021. The survey tool was administered online to the study participants. Key questions explored the following outcome measures: countries with oral health policies; the thrusts of the oral health policies; policy thrusts targeting young children; and dental care plans as a component of a universal health care plan. Descriptive statistics were conducted to determine the number of countries with any of the study outcome measures and coverage per country. Results: Sixty (38%) of the 158 FDI member-countries responded to the survey. Forty-eight (55.2%) of the 60 countries had a national oral health policy document or position statement on oral health; 54 (62.1%) countries had plans on universal health care, and 42 (48.3%) included dental care within their universal health care plan. The most common policy thrusts addressing the oral health needs of children were the promotion of oral hygiene (71.7%), provision of fluoride products for children (53.3%), collaboration with primary care providers (35%), and prenatal oral health education (50%). There were differences in the scope of oral health care coverage and the coverage for young children between continents as well as between countries. Europe had many countries with children-friendly oral health policy coverage. Conclusions: About half of the surveyed countries had a national oral health policy. There were variations in the scope of oral health care coverage, particularly for young children, both between continents and among individual countries. These findings underscore the importance of understanding the landscape of oral health policies globally. Such insights can help inform targeted interventions to enhance oral health policies, thereby contributing to improved oral health outcomes on a global level.

11.
J Pers Med ; 14(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673035

RESUMO

INTRODUCTION: The protocol for deceased donor kidney transplants has been standardised. The procedure for a living donor has peculiarities derived from the differences in the graft. When a living kidney donor program is implemented, changes occur in both the profile of the kidney transplant candidate and in the postoperative treatments. AIMS: To discover whether a living donor program influences the functional outcomes of kidney grafts in a longstanding classical deceased donor kidney transplant program and to identify the factors associated with transplant outcomes. METHODS: Retrospective observational multicentre study. SAMPLE: Kidney transplant patients in two urology referral centres for renal transplant in Spain between 1994 and 2019. Groups: TV (living transplant): patients given kidney transplants from living donors (n = 150); TCpre11 (deceased transplant previous to 2011): patients given kidney transplants from deceased donors before the living donor program was implemented (n = 650); and TCpost11 (deceased transplant after 2011): patients given kidney transplants from deceased donors after the living donor program was implemented (n = 500). RESULTS: Mean age was 55.75 years (18-80 years), higher in TCpre11. There were 493 female patients (37.92%) and 1007 male patients (62.08%). Mean body mass index (BMI) was 26.69 kg/m2 (17.50-42.78 kg/m2), higher in TCpre11. Mean ischemia time was 17.97 h (6-29 h), higher in TCpost11. Median duration of urethral catheter: 8 days (6-98 days), higher in TCpost11. Median duration of double-J ureteral stent: 58 days (24-180 days), higher in TCpost11. Pretransplant UTIs: 17.77%, higher in TCpre11 (25.69%) than in TV (12%), higher in TV (12%) than TCpost11 (9.2%), and higher in TCpre11 (25.69%) than TCpost11 (9.2%). Acute renal rejection in 9.33% of TV, 14.77% of TCpre11, and 9.8% of TCpost11. Multivariate analysis: TCpost11 featured higher BMI, more smoking, and chronic renal failure progression time. Lower use of nonantibiotic prophylaxis to prevent recurrent urinary tract infections, increased duration of urethral catheters due to obstructive problems, and favoured deterioration of kidney function was observed in the deceased donor program. The living donor (LD) program had a strong influence on deceased donor transplants in the prelysis phase. Implementation of a LD program was associated with a decrease in the likelihood of acute rejection in TCpost11 and an increase in the tendency towards normal kidney function. CONCLUSIONS: Implementing living donor transplant programs affects functional outcomes in deceased donor transplants, reducing the probability of acute rejection and increasing the tendency towards normal kidney function. Preventing recurrent urinary tract infections with measures other than antibiotics, smoking cessation, delaying the removal of the double-J stent from the graft, and pre-emptive transplant (transplant prior to dialysis) are associated with improved renal function of the graft.

12.
J Indian Soc Pedod Prev Dent ; 42(1): 3-8, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616420

RESUMO

Early childhood caries is a major public health issue in India. The primary reason for poor oral health in children is a lack of awareness about the role of primary teeth and the importance of an early dental visit for infants and toddlers. The primary objectives of an early dental visit are to analyze the child's risk level, provide guidance to parents regarding proper oral hygiene measures, review dietary and eating habits, provide information regarding the infectivity of dental caries, review the risks of traumatic injuries and discuss factors which affect the development of occlusion. Through this paper, we are proposing an "Age One" policy that recognizes dentists, physicians, allied health professionals, community health-care workers, and nongovernmental organizations to work toward a child's overall health as partners to achieve this goal. The expectation is that this policy will provide guidance to childcare centers, pediatric dentists, other health-care professionals, and legislators regarding oral health activities and the promotion of oral health in infants. The purpose of the policy is to lay the foundation for a lifetime of preventive education and dental care, to help ensure optimal oral health beginning in childhood and continuing through the life course.


Assuntos
Cárie Dentária , Saúde Bucal , Pré-Escolar , Lactente , Criança , Humanos , Cárie Dentária/prevenção & controle , Escolaridade , Odontólogos , Políticas
13.
Neurocrit Care ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649651

RESUMO

BACKGROUND: We performed an analysis of a large intensive care unit electronic database to provide preliminary estimates of various blood pressure parameters in patients with acute stroke receiving intravenous (IV) antihypertensive medication and determine the relationship with in-hospital outcomes. METHODS: We identified the relationship between pre-treatment and post-treatment systolic blood pressure (SBP) and heart rate (HR)-related variables and in-hospital mortality and acute kidney injury in patients with acute stroke receiving IV clevidipine, nicardipine, or nitroprusside using data provided in the Medical Information Mart for Intensive Care (MIMIC) IV database. RESULTS: A total of 1830 patients were treated with IV clevidipine (n = 64), nicardipine (n = 1623), or nitroprusside (n = 143). The standard deviations [SDs] of pre-treatment SBP (16.3 vs. 13.7, p ≤ 0.001) and post-treatment SBP (15.4 vs. 14.4, p = 0.004) were higher in patients who died compared with those who survived, particularly in patients with intracerebral hemorrhage (ICH). The mean SBP was significantly lower post treatment compared with pre-treatment values for clevidipine (130.7 mm Hg vs. 142.5 mm Hg, p = 0.006), nicardipine (132.8 mm Hg vs. 141.6 mm Hg, p ≤ 0.001), and nitroprusside (126.2 mm Hg vs. 139.6 mm Hg, p ≤ 0.001). There were no differences in mean SDs post treatment compared with pre-treatment values for clevidipine (14.5 vs. 13.5, p = 0.407), nicardipine (14.2 vs. 14.6, p = 0.142), and nitroprusside (14.8 vs. 14.8, p = 0.997). The SDs of pre-treatment and post-treatment SBP were not significantly different in patients with ischemic stroke treated with IV clevidipine, nicardipine, or nitroprusside or for patients with ICH treated with IV clevidipine or nitroprusside. However, patients with ICH treated with IV nicardipine had a significantly higher SD of post-treatment SBP (13.1 vs. 14.2, p = 0.0032). CONCLUSIONS: We found that SBP fluctuations were associated with in-hospital mortality in patients with acute stroke. IV antihypertensive medication reduced SBP but did not reduce SBP fluctuations in this observational study. Our results highlight the need for optimizing therapeutic interventions to reduce SBP fluctuations in patients with acute stroke.

16.
Microb Genom ; 10(3)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38451250

RESUMO

Cycads are known to host symbiotic cyanobacteria, including Nostocales species, as well as other sympatric bacterial taxa within their specialized coralloid roots. Yet, it is unknown if these bacteria share a phylogenetic origin and/or common genomic functions that allow them to engage in facultative symbiosis with cycad roots. To address this, we obtained metagenomic sequences from 39 coralloid roots sampled from diverse cycad species and origins in Australia and Mexico. Culture-independent shotgun metagenomic sequencing was used to validate sub-community co-cultures as an efficient approach for functional and taxonomic analysis. Our metanalysis shows a host-independent microbiome core consisting of seven bacterial orders with high species diversity within the identified taxa. Moreover, we recovered 43 cyanobacterial metagenome-assembled genomes, and in addition to Nostoc spp., symbiotic cyanobacteria of the genus Aulosira were identified for the first time. Using this robust dataset, we used phylometagenomic analysis to reveal three monophyletic cyanobiont clades, two host-generalist and one cycad-specific that includes Aulosira spp. Although the symbiotic clades have independently arisen, they are enriched in certain functional genes, such as those related to secondary metabolism. Furthermore, the taxonomic composition of associated sympatric bacterial taxa remained constant. Our research quadruples the number of cycad cyanobiont genomes and provides a robust framework to decipher cyanobacterial symbioses, with the potential of improving our understanding of symbiotic communities. This study lays a solid foundation to harness cyanobionts for agriculture and bioprospection, and assist in conservation of critically endangered cycads.


Assuntos
Genômica , Simbiose , Filogenia , Austrália , Técnicas de Cocultura
17.
Curr Opin Microbiol ; 78: 102448, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38447313

RESUMO

Streptomyces are a large genus of multicellular bacteria best known for their prolific production of bioactive natural products. In addition, they play key roles in the mineralisation of insoluble resources, such as chitin and cellulose. Because of their multicellular mode of growth, colonies of interconnected hyphae extend over a large area that may experience different conditions in different parts of the colony. Here, we argue that within-colony phenotypic heterogeneity can allow colonies to simultaneously respond to divergent inputs from resources or competitors that are spatially and temporally dynamic. We discuss causal drivers of heterogeneity, including competitors, precursor availability, metabolic diversity and division of labour, that facilitate divergent phenotypes within Streptomyces colonies. We discuss the adaptive causes and consequences of within-colony heterogeneity, highlight current knowledge (gaps) and outline key questions for future studies.


Assuntos
Streptomyces , Streptomyces/genética , Fenótipo
18.
Toxins (Basel) ; 16(2)2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38393182

RESUMO

Snakebite accident treatment requires the administration of antivenoms that provide efficacy and effectiveness against several snake venoms of the same genus or family. The low number of immunogenic components in venom mixtures that allow the production of antivenoms consequently gives them partial neutralization and a suboptimal pharmacological response. This study evaluates the immunorecognition and neutralizing efficacy of the polyvalent anticoral antivenom from the Instituto Nacional de Salud (INS) of Colombia against the heterologous endemic venoms of Micrurus medemi, and M. sangilensis, and M. helleri by assessing immunoreactivity through affinity chromatography, ELISA, Western blot, and neutralization capability. Immunorecognition towards the venoms of M. medemi and M. sangilensis showed values of 62% and 68% of the protein composition according to the immunoaffinity matrix, respectively. The analysis by Western blot depicted the highest recognition patterns for M. medemi, followed by M. sangilensis, and finally by M. helleri. These findings suggest that the venom compositions are closely related and exhibit similar recognition by the antivenom. According to enzyme immunoassays, M. helleri requires a higher amount of antivenom to achieve recognition than the others. Besides reinforcing the evaluation of INS antivenom capability, this work recommends the use of M. helleri in the production of Colombian antisera.


Assuntos
Antivenenos , Cobras Corais , Animais , Cobras Corais/metabolismo , Colômbia , Venenos Elapídicos/química , Venenos de Serpentes/química
19.
Intensive Care Med ; 50(2): 258-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38353714

RESUMO

PURPOSE: This study aimed to determine the best strategy to achieve fast and safe extubation. METHODS: This multicenter trial randomized patients with primary respiratory failure and low-to-intermediate risk for extubation failure with planned high-flow nasal cannula (HFNC) preventive therapy. It included four groups: (1) conservative screening with ratio of partial pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FiO2) ≥ 150 and positive end-expiratory pressure (PEEP) ≤ 8 cmH2O plus conservative spontaneous breathing trial (SBT) with pressure support 5 cmH2O + PEEP 0 cmH2O); (2) screening with ratio of partial pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FiO2) ≥ 150 and PEEP ≤ 8 plus aggressive SBT with pressure support 8 + PEEP 5; (3) aggressive screening with PaO2/FiO2 > 180 and PEEP 10 maintained until the SBT with pressure support 8 + PEEP 5; (4) screening with PaO2/FiO2 > 180 and PEEP 10 maintained until the SBT with pressure support 5 + PEEP 0. Primary outcomes were time-to-extubation and simple weaning rate. Secondary outcomes included reintubation within 7 days after extubation. RESULTS: Randomization to the aggressive-aggressive group was discontinued at the interim analysis for safety reasons. Thus, 884 patients who underwent at least 1 SBT were analyzed (conservative-conservative group, n = 256; conservative-aggressive group, n = 267; aggressive-conservative group, n = 261; aggressive-aggressive, n = 100). Median time to extubation was lower in the groups with aggressive screening (p < 0.001). Simple weaning rates were 45.7%, 76.78% (205 patients), 71.65%, and 91% (p < 0.001), respectively. Reintubation rates did not differ significantly (p = 0.431). CONCLUSION: Among patients at low or intermediate risk for extubation failure with planned HFNC, combining aggressive screening with preventive PEEP and a conservative SBT reduced the time to extubation without increasing the reintubation rate.


Assuntos
Extubação , Artérias , Humanos , Pressão Parcial , Pressão , Oxigênio
20.
Metab Eng ; 82: 79-88, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290598

RESUMO

A significant problem during recombinant protein production is proteolysis. One of the most common preventive strategies is the addition of protease inhibitors, which has drawbacks, such as their short half-life and high cost, and their limited prevention of extracellular proteolysis. Actinomycetes produce the most commonly used inhibitors, which are non-ribosomal small aldehydic peptides. Previously, an unprecedented biosynthetic route involving a condensation-minus non-ribosomal peptide synthetase (NRPSs) and a tRNA utilizing enzyme (tRUE) was shown to direct the synthesis of one of these inhibitor peptides, livipeptin. Here, we show that expression of the livipeptin biosynthetic pathway encoded by the lvp genes in CHO cells resulted in the production of this metabolite with cysteine protease inhibitory activity, implying that mammalian tRNAs were recruited by the lvp system. CHO cells transiently expressing the biosynthetic pathway produced livipeptin without affecting cell growth or viability. Expression of the lvp system in CHO cells producing two model proteins, secreted alkaline phosphatase (hSeAP) and a monoclonal antibody, resulted in higher specific productivity with reduced proteolysis. We show for the first time that the expression of a bacterial biosynthetic pathway is functional in CHO cells, resulting in the efficient, low-cost synthesis of a protease inhibitor without adverse effects on CHO cells. This expands the field of metabolic engineering of mammalian cells by expressing the overwhelming diversity of actinomycetes biosynthetic pathways and opens a new option for proteolysis inhibition in bioprocess engineering.


Assuntos
Vias Biossintéticas , Peptídeos , Cricetinae , Animais , Cricetulus , Proteólise , Células CHO , Proteínas Recombinantes
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