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1.
Proc Natl Acad Sci U S A ; 121(25): e2316376121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38861603

RESUMO

Human parainfluenza virus type 3 (HPIV3) is a major pediatric respiratory pathogen lacking available vaccines or antiviral drugs. We generated live-attenuated HPIV3 vaccine candidates by codon-pair deoptimization (CPD). HPIV3 open reading frames (ORFs) encoding the nucleoprotein (N), phosphoprotein (P), matrix (M), fusion (F), hemagglutinin-neuraminidase (HN), and polymerase (L) were modified singly or in combination to generate 12 viruses designated Min-N, Min-P, Min-M, Min-FHN, Min-L, Min-NP, Min-NPM, Min-NPL, Min-PM, Min-PFHN, Min-MFHN, and Min-PMFHN. CPD of N or L severely reduced growth in vitro and was not further evaluated. CPD of P or M was associated with increased and decreased interferon (IFN) response in vitro, respectively, but had little effect on virus replication. In Vero cells, CPD of F and HN delayed virus replication, but final titers were comparable to wild-type (wt) HPIV3. In human lung epithelial A549 cells, CPD F and HN induced a stronger IFN response, viral titers were reduced 100-fold, and the expression of F and HN proteins was significantly reduced without affecting N or P or the relative packaging of proteins into virions. Following intranasal infection in hamsters, replication in the nasal turbinates and lungs tended to be the most reduced for viruses bearing CPD F and HN, with maximum reductions of approximately 10-fold. Despite decreased in vivo replication (and lower expression of CPD F and HN in vitro), all viruses induced titers of serum HPIV3-neutralizing antibodies similar to wt and provided complete protection against HPIV3 challenge. In summary, CPD of HPIV3 yielded promising vaccine candidates suitable for further development.


Assuntos
Códon , Vírus da Parainfluenza 3 Humana , Vacinas Atenuadas , Replicação Viral , Animais , Vírus da Parainfluenza 3 Humana/imunologia , Vírus da Parainfluenza 3 Humana/genética , Humanos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/genética , Códon/genética , Cricetinae , Infecções por Respirovirus/imunologia , Infecções por Respirovirus/prevenção & controle , Infecções por Respirovirus/virologia , Chlorocebus aethiops , Células Vero , Fases de Leitura Aberta/genética , Mesocricetus , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Vacinas Virais/imunologia , Vacinas Virais/genética , Proteínas Virais/imunologia , Proteínas Virais/genética , Vacinas contra Parainfluenza/imunologia , Vacinas contra Parainfluenza/genética
2.
Acta Paediatr ; 113(4): 733-738, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38182549

RESUMO

AIM: The aim of this study was to assess outcomes of peritoneal drainage and laparotomy in the management of intestinal perforation secondary to necrotizing enterocolitis (NEC) and spontaneous intestinal perforation. METHODS: A retrospective review of all preterm infants (birthweight ≤1500 g) who underwent surgical intervention (peritoneal drainage and/or laparotomy) for intestinal perforation between March 2010 and March 2020. RESULTS: A total of 43 infants who underwent surgical intervention for intestinal perforation were included [19 (44%) with NEC and 24 (56%) with spontaneous intestinal perforation]. Peritoneal drainage was more commonly placed as the initial surgical procedure for management of spontaneous intestinal perforation compared with surgical NEC [23 (96%) vs. 11 (58%), p = 0.003]. Mortality was greater for infants who were initially managed with peritoneal drainage [11 (32%)] compared with those who underwent primary laparotomy [2 (22%), p = 0.5]. CONCLUSION: Initial surgical management of intestinal perforation is more often according to underlying pathology. Our data support primary laparotomy for infants with perforated NEC.


Assuntos
Enterocolite Necrosante , Perfuração Intestinal , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Peso ao Nascer , Laparotomia , Drenagem/métodos , Estudos Retrospectivos , Enterocolite Necrosante/complicações , Enterocolite Necrosante/cirurgia
3.
Cardiol Young ; : 1-7, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38163988

RESUMO

BACKGROUND: CHD is a significant risk factor for the development of necrotising enterocolitis. Existing literature does not differentiate between term and preterm populations. Long-term outcomes of these patients are not well understood. The aim was to investigate the baseline characteristics and outcomes of term normal birth weight infants with CHD who developed necrotising enterocolitis. METHODS: A retrospective review was performed of infants from a single tertiary centre with CHD who developed necrotising enterocolitis of Bell's Stage 1-3, over a ten-year period. Inclusion criteria was those born greater than 36 weeks' gestation and birth weight over 2500g. Exclusion criteria included congenital gastro-intestinal abnormalities. Sub-group analysis was performed using Fisher's exact test. RESULTS: Twenty-five patients were identified, with a median gestational age of 38 weeks. Patients with univentricular physiology accounted for 32% (n = 8) and 52% of patients (n = 13) had a duct-dependent lesion. Atrioventricular septal defect was the most common cardiac diagnosis (n = 6, 24%). Patients with trisomy 21 accounted for 20% of cases. Mortality within 30 days of necrotising enterocolitis was 20%. Long-term mortality was 40%, which increased with increasing Bell's Stage. In total, 36% (n = 9) required surgical management of necrotising enterocolitis, the rate of which was significantly higher in trisomy 21 cases (p < 0.05). CONCLUSION: Not previously described in term infants is the high rate of trisomy 21 and atrioventricular septal defect. This may reflect higher baseline incidence in our population. Infants with trisomy 21 were more likely to develop surgical necrotising enterocolitis. Mortality at long-term follow-up was high in patients with Bell's Stage 2-3.

4.
Am J Med Genet A ; 191(12): 2884-2889, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37638701

RESUMO

We present a female patient with a complex sex chromosomal rearrangement [GRCh38] Xp22.33(10701_981101)x1,Yq11.221q11.23(13948013_26483746)x1 who conceived spontaneously and carried a healthy pregnancy to term. The patient presented with extreme short stature (more than 4SD below expected) and a bilateral Madelung deformity suggesting a possible SHOX deletion. The patient was otherwise medically well. This patient's short stature was found to be a result of a complex chromosome rearrangement involving a partial X chromosome deletion, which included the SHOX gene and a gain of Y chromosomal material. The Y chromosome material did not contain the SRY gene locus. This is the first recorded case to date of this rearrangement in a female who spontaneously conceived which resulted in a live birth. This patient had normal external and internal anatomy and normal endocrine evaluation with normal puberty. X-inactivation studies revealed no evidence of skewed inactivation.


Assuntos
Nanismo , Proteínas de Homeodomínio , Gravidez , Humanos , Feminino , Proteínas de Homeodomínio/genética , Proteína de Homoeobox de Baixa Estatura/genética , Cromossomo Y , Aberrações Cromossômicas , Transtornos do Crescimento/genética
5.
Anesth Analg ; 137(3): 508-520, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37590795

RESUMO

Substance use disorders (SUDs) represent a current major public health concern in the United States and around the world. Social and economic stressors secondary to the coronavirus disease 2019 (COVID-19) pandemic have likely led to an increase in SUDs around the world. This chronic, debilitating disease is a prevalent health problem, and yet many clinicians do not have adequate training or clinical experience diagnosing and treating SUDs. Anesthesiologists and other perioperative medical staff frequently encounter patients with co-occurring SUDs. By such, through increased awareness and education, physicians and other health care providers have a unique opportunity to positively impact the lives and improve the perioperative outcomes of patients with SUDs. Understanding commonly used terms, potentially effective perioperative screening tools, diagnostic criteria, basics of treatment, and the perioperative implications of SUDs is essential to providing adequate care to patients experiencing this illness.


Assuntos
COVID-19 , Médicos , Transtornos Relacionados ao Uso de Substâncias , Humanos , Anestesiologistas , Escolaridade , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/terapia
6.
Curr Opin Anaesthesiol ; 36(1): 68-73, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36550607

RESUMO

PURPOSE OF REVIEW: Emphasizing a systems-based approach, we discuss the timing for referral for perioperative surgical consultation. This review then highlights several types of comorbidities that may complicate thoracic procedures, and references recent best practices for their management. RECENT FINDINGS: Patients requiring thoracic surgeries present some of the most challenging cases for both intraoperative and postoperative management. The recent SARS-CoV-2 pandemic has only exacerbated these concerns. Effective preoperative optimization, however, provides for identification of patient comorbidities, allowing for mitigation of surgical risks. This kind of planning is multidisciplinary by nature. We believe patients benefit from early engagement of a dedicated preoperative clinic experienced for caring for complex surgical patients. SUMMARY: Optimizing patients for thoracic surgery can be challenging for small and large health systems alike. Implementation of evidence-based guidelines can improve care and mitigate risk. As surgical techniques evolve, future research is needed to ensure that perioperative care continues to progress.


Assuntos
COVID-19 , Cirurgia Torácica , Procedimentos Cirúrgicos Torácicos , Humanos , SARS-CoV-2 , Procedimentos Cirúrgicos Torácicos/efeitos adversos , Assistência Perioperatória , Cuidados Pré-Operatórios/métodos
7.
J Neuroeng Rehabil ; 19(1): 108, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209094

RESUMO

We diagnosed 66 peripheral nerve injuries in 34 patients who survived severe coronavirus disease 2019 (COVID-19). We combine this new data with published case series re-analyzed here (117 nerve injuries; 58 patients) to provide a comprehensive accounting of lesion sites. The most common are ulnar (25.1%), common fibular (15.8%), sciatic (13.1%), median (9.8%), brachial plexus (8.7%) and radial (8.2%) nerves at sites known to be vulnerable to mechanical loading. Protection of peripheral nerves should be prioritized in the care of COVID-19 patients. To this end, we report proof of concept data of the feasibility for a wearable, wireless pressure sensor to provide real time monitoring in the intensive care unit setting.


Assuntos
Plexo Braquial , COVID-19 , Traumatismos dos Nervos Periféricos , Dispositivos Eletrônicos Vestíveis , Plexo Braquial/lesões , COVID-19/diagnóstico , Estudos de Viabilidade , Humanos
8.
J Oral Implantol ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473175

RESUMO

Replacement of missing teeth is becoming more prevalent, currently with more than 700,000 dental implants being placed every year. Patients seek out dental treatment with the expectations of having procedures performed in the least number of time/visits, for as inexpensive as possible, and at the highest quality. As this continues, clinicians can adapt with changing times and adopt the newer advancements in digital dentistry. This case letter aims to provide readers with insight to integration of digital workflows to optimize patient and clinician outcomes with single tooth implant therapy.

9.
Am J Respir Crit Care Med ; 202(4): e74-e87, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32795139

RESUMO

Background: Noninvasive ventilation (NIV) is used for patients with chronic obstructive pulmonary disease (COPD) and chronic hypercapnia. However, evidence for clinical efficacy and optimal management of therapy is limited.Target Audience: Patients with COPD, clinicians who care for them, and policy makers.Methods: We summarized evidence addressing five PICO (patients, intervention, comparator, and outcome) questions. The GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach was used to evaluate the certainty in evidence and generate actionable recommendations. Recommendations were formulated by a panel of pulmonary and sleep physicians, respiratory therapists, and methodologists using the Evidence-to-Decision framework.Recommendations:1) We suggest the use of nocturnal NIV in addition to usual care for patients with chronic stable hypercapnic COPD (conditional recommendation, moderate certainty); 2) we suggest that patients with chronic stable hypercapnic COPD undergo screening for obstructive sleep apnea before initiation of long-term NIV (conditional recommendation, very low certainty); 3) we suggest not initiating long-term NIV during an admission for acute-on-chronic hypercapnic respiratory failure, favoring instead reassessment for NIV at 2-4 weeks after resolution (conditional recommendation, low certainty); 4) we suggest not using an in-laboratory overnight polysomnogram to titrate NIV in patients with chronic stable hypercapnic COPD who are initiating NIV (conditional recommendation, very low certainty); and 5) we suggest NIV with targeted normalization of PaCO2 in patients with hypercapnic COPD on long-term NIV (conditional recommendation, low certainty).Conclusions: This expert panel provides evidence-based recommendations addressing the use of NIV in patients with COPD and chronic stable hypercapnic respiratory failure.


Assuntos
Hipercapnia/terapia , Ventilação não Invasiva/normas , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Crônica , Humanos , Hipercapnia/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Fatores de Tempo
10.
Clin Linguist Phon ; 34(3): 222-241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31195836

RESUMO

We present a case of sudden onset, acquired altered accent in the speech of NL, a 48-year-old, left-handed female. NL's typical Standard Southern British English accent was preserved in singing and reading, but altered in recitation, repetition and spontaneous speech. Neuropsychological investigation, impressionistic and acoustic analysis of accented and unaccented speech are documented. The altered accent displays a slower speech rate and longer duration of consonants and vowels. There is evidence for a shift towards syllable-timed rhythm. NL's altered accent displays atypical coordination between voicing and supra-laryngeal articulation, reduced mean and range of F0, and minor differences in vowel space. These features are broadly consistent with other documented cases of Foreign Accent Syndrome, regardless of aetiology. However, NL's profile of preserved and impaired speech does not fit any pattern typically associated with organic neurological disorder. Moreover, left-handed preference may contribute to differences between singing and reading, versus recitation, repetition and spontaneous speech.


Assuntos
Transtornos da Articulação/psicologia , Idioma , Multilinguismo , Acústica da Fala , Voz , Feminino , Cefaleia/etiologia , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Estudos Retrospectivos
11.
Respirology ; 24(12): 1204-1211, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31012225

RESUMO

BACKGROUND AND OBJECTIVE: Patients with chronic respiratory failure are increasingly managed with domiciliary non-invasive ventilation (NIV). There may be limited ability to provide NIV titration for these complex patients, and ventilatory requirements and upper airway support needs may change over time. Therefore, an automatically adjusting expiratory positive airway pressure (AutoEPAP) algorithm may offer advantages over manually adjusted EPAP for treating these patients. This study compared 4% oxygen desaturation index (ODI4%) values during the use of an AutoEPAP algorithm versus manual EPAP titration with the intelligent volume-assured pressure support (iVAPS) algorithm. METHODS: This prospective, single-blind, randomized, crossover study was conducted at six US sites. Patients with chronic respiratory failure (neuromuscular disease, chronic obstructive pulmonary disease, obesity hypoventilation and other aetiologies) and an apnoea-hypopnoea index of >5/h who were already established NIV users underwent a single night of NIV with the iVAPS manual EPAP and iVAPS AutoEPAP in the sleep laboratory in random order. RESULTS: A total of 38 patients constituted the study population. Mean ODI4% was statistically non-inferior with AutoEPAP versus manual EPAP (P < 0.0001). There was no difference in the effect on ODI4% across respiratory failure subgroups. Ventilation parameters and gas exchange were similar with either NIV mode, indicating equally effective treatment of respiratory failure. Sleep parameters were improved during AutoEPAP versus manual EPAP. CONCLUSION: A single night of NIV using the iVAPS with AutoEPAP algorithm was non-inferior to a single night of iVAPS with manual EPAP titration in patients with respiratory failure. CLINICAL TRIAL REGISTRATION: NCT02683772 at clinicaltrials.gov.


Assuntos
Ventilação não Invasiva , Síndrome de Hipoventilação por Obesidade/terapia , Respiração com Pressão Positiva , Doença Pulmonar Obstrutiva Crônica/terapia , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/complicações , Ventilação não Invasiva/efeitos adversos , Ventilação não Invasiva/métodos , Síndrome de Hipoventilação por Obesidade/diagnóstico , Respiração com Pressão Positiva/efeitos adversos , Respiração com Pressão Positiva/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Método Simples-Cego , Sono/fisiologia , Resultado do Tratamento
12.
Am J Respir Cell Mol Biol ; 57(6): 692-701, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28723225

RESUMO

Type 2-associated goblet cell hyperplasia and mucus hypersecretion are well known features of asthma. 15-Lipoxygenase-1 (15LO1) is induced by the type 2 cytokine IL-13 in human airway epithelial cells (HAECs) in vitro and is increased in fresh asthmatic HAECs ex vivo. 15LO1 generates a variety of products, including 15-hydroxyeicosatetraenoic acid (15-HETE), 15-HETE-phosphatidylethanolamine (15-HETE-PE), and 13-hydroxyoctadecadienoic acid (13-HODE). In this study, we investigated the 15LO1 metabolite profile at baseline and after IL-13 treatment, as well as its influence on goblet cell differentiation in HAECs. Primary HAECs obtained from bronchial brushings of asthmatic and healthy subjects were cultured under air-liquid interface culture supplemented with arachidonic acid and linoleic acid (10 µM each) and exposed to IL-13 for 7 days. Short interfering RNA transfection and 15LO1 inhibition were applied to suppress 15LO1 expression and activity. IL-13 stimulation induced expression of 15LO1 and preferentially generated 15-HETE-PE in vitro, both of which persisted after removal of IL-13. 15LO1 inhibition (by short interfering RNA and chemical inhibitor) decreased IL-13-induced forkhead box protein A3 (FOXA3) expression and enhanced FOXA2 expression. These changes were associated with reductions in both mucin 5AC and periostin. Exogenous 15-HETE-PE stimulation (alone) recapitulated IL-13-induced FOXA3, mucin 5AC, and periostin expression. The results of this study confirm the central importance of 15LO1 and its primary product, 15-HETE-PE, for epithelial cell remodeling in HAECs.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Caliciformes/metabolismo , Ácidos Hidroxieicosatetraenoicos/biossíntese , Interleucina-13/farmacologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Araquidonato 15-Lipoxigenase/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fator 3-beta Nuclear de Hepatócito/biossíntese , Fator 3-gama Nuclear de Hepatócito/biossíntese , Humanos , Ácidos Linoleicos/biossíntese , Mucina-5AC/biossíntese
13.
Nat Chem Biol ; 11(9): 691-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26214255

RESUMO

The complex plant flavonol glycoside montbretin A is a potent (Ki = 8 nM) and specific inhibitor of human pancreatic α-amylase with potential as a therapeutic for diabetes and obesity. Controlled degradation studies on montbretin A, coupled with inhibition analyses, identified an essential high-affinity core structure comprising the myricetin and caffeic acid moieties linked via a disaccharide. X-ray structural analyses of the montbretin A-human α-amylase complex confirmed the importance of this core structure and revealed a novel mode of glycosidase inhibition wherein internal π-stacking interactions between the myricetin and caffeic acid organize their ring hydroxyls for optimal hydrogen bonding to the α-amylase catalytic residues D197 and E233. This novel inhibitory motif can be reproduced in a greatly simplified analog, offering potential for new strategies for glycosidase inhibition and therapeutic development.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/química , Flavonóis/química , Glicosídeos/química , alfa-Amilases/química , Sítios de Ligação , Ácidos Cafeicos/química , Sequência de Carboidratos , Inibidores Enzimáticos/síntese química , Flavonas/química , Flavonoides/química , Expressão Gênica , Humanos , Ligação de Hidrogênio , Hidrólise , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Pichia/genética , Pichia/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Trissacarídeos/química , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/genética
15.
J Ark Med Soc ; 113(7): 164-165, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30085463

RESUMO

We all know that acne vulgaris ' is very common. That is why it is called vulgaris which means common. We are wanting to present however that yeast acne is also common. In fact, yeast may be found on the skin in 75-98% of healthy people. Under particular biological conditions, homeostasis of the skin microbiome fails and growth of the fungi exceeds ideal levels. When this happens, "yeast acne" can occur. We feel that the incidence of yeast acne has been increasing in prevalence in our clinic, especially in young adult males, and so we wrote this paper in order to increase awareness.


Assuntos
Acne Vulgar/microbiologia , Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Malassezia/isolamento & purificação , Propionibacterium acnes/isolamento & purificação , Humanos , Fatores de Risco
16.
Mol Cell Biochem ; 411(1-2): 373-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26547551

RESUMO

Diabetes is an increasingly prevalent disease state with a global impact. It is important that effective and cost-efficient methods be developed to treat this disease state. Zucker diabetic fatty rats, an animal model of type 2 diabetes, were treated with montbretin A (MbA), a selective human pancreatic α-amylase inhibitor, isolated from the corms of the Crocosmia crocosmiiflora plant that may have potential as a glucose-lowering agent. The study purpose was to determine if MbA was an orally effective treatment for diabetes. The effect of MbA was compared to a current clinical treatment modality, acarbose that is associated with gastrointestinal side effects known to affect patient compliance. MbA and acarbose were administered daily in the drinking water. Body weight and fluid intake were measured daily to calculate dose consumption. Plasma glucose levels were determined twice weekly in both the fed and fasted state. At termination samples were collected to assess increased risk of secondary complications related to diabetes and oxidative stress. There was no effect of either MbA or acarbose treatment on insulin levels. Plasma glucose levels were significantly lower following MbA treatment in the ZT group which persisted throughout the study period (day 49: 12.1 ± 1.2 mM). However, while there was an initial decrease in plasma glucose levels in the acarbose-treated fatty group, this effect was not sustained (day 49: 20.6 ± 1.3 mM) through to termination. MbA improved the oxidative status of the fatty diabetic animals as well as attenuated markers for increased risk of cardiovascular complications associated with diabetes. This study demonstrated that, at a lower dose as compared to acarbose (10 mg/kg/day), chronic oral administration of MbA (7.5 mg/kg/day) was an effective glucose-lowering agent in the treatment of type 2 diabetes.


Assuntos
Glicemia/metabolismo , Flavonas/farmacologia , Hipoglicemiantes/farmacologia , Trissacarídeos/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Masculino , Ratos , Ratos Zucker
18.
J Virol ; 88(12): 6690-701, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696472

RESUMO

UNLABELLED: In previous work, a prototypic recombinant vesicular stomatitis virus Indiana serotype (rVSIV) vector expressing simian immunodeficiency virus (SIV) gag and human immunodeficiency virus type 1 (HIV-1) env antigens protected nonhuman primates (NHPs) from disease following challenge with an HIV-1/SIV recombinant (SHIV). However, when tested in a stringent NHP neurovirulence (NV) model, this vector was not adequately attenuated for clinical evaluation. For the work described here, the prototypic rVSIV vector was attenuated by combining specific G protein truncations with either N gene translocations or mutations (M33A and M51A) that ablate expression of subgenic M polypeptides, by incorporation of temperature-sensitive mutations in the N and L genes, and by deletion of the VSIV G gene to generate a replicon that is dependent on trans expression of G protein for in vitro propagation. When evaluated in a series of NHP NV studies, these attenuated rVSIV variants caused no clinical disease and demonstrated a very significant reduction in neuropathology compared to wild-type VSIV and the prototypic rVSIV vaccine vector. In spite of greatly increased in vivo attenuation, some of the rVSIV vectors elicited cell-mediated immune responses that were similar in magnitude to those induced by the much more virulent prototypic vector. These data demonstrate novel approaches to the rational attenuation of VSIV NV while retaining vector immunogenicity and have led to identification of an rVSIV N4CT1gag1 vaccine vector that has now successfully completed phase I clinical evaluation. IMPORTANCE: The work described in this article demonstrates a rational approach to the attenuation of vesicular stomatitis virus neurovirulence. The major attenuation strategy described here will be most likely applicable to other members of the Rhabdoviridae and possibly other families of nonsegmented negative-strand RNA viruses. These studies have also enabled the identification of an attenuated, replication-competent rVSIV vector that has successfully undergone its first clinical evaluation in humans. Therefore, these studies represent a major milestone in the development of attenuated rVSIV, and likely other vesiculoviruses, as a new vaccine platform(s) for use in humans.


Assuntos
Vacinas contra a AIDS/imunologia , Sistema Nervoso Central/virologia , Vetores Genéticos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Macaca fascicularis , Vírus da Estomatite Vesicular Indiana/imunologia , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/genética , Animais , Anticorpos Antivirais/imunologia , Sistema Nervoso Central/imunologia , Modelos Animais de Doenças , Vetores Genéticos/genética , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , Humanos , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Macaca fascicularis/virologia , Masculino , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vírus da Estomatite Vesicular Indiana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/administração & dosagem , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
20.
J Infect Dis ; 210(10): 1658-69, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25001458

RESUMO

BACKGROUND: Some Streptococcus pneumoniae serotypes express an ahemolytic pneumolysin (PLYa). Serotypes that commonly express PLYa, including serotype 8 (ST8) and ST1, are often associated with a low prevalence during colonization but a higher propensity to cause invasive disease. We sought to study the host response to ST8 PLYa in a homologous and heterologous capsular background. METHODS: We genetically exchanged the PLYa of ST8 strain 6308 with the hemolytic PLY (PLYh) of ST3 A66.1 and vice versa and determined the impact of the exchange on nasopharyngeal colonization in mice. Then, to compare the response of human cells to PLYa-expressing and PLYh-expressing strains, we infected human peripheral blood mononuclear cells (PBMCs) with PLY-switched strains and assessed dendritic cell and CD4(+) T-cell responses by intracellular cytokine staining. RESULT: Mice colonized with PLYa-expressing strains had significantly higher colonization densities than those colonized with PLYh-expressing strains, irrespective of capsular background. Compared with infection of PBMCs with PLYh-expressing strains, infection with PLYa-expressing strains induced diminished innate (dendritic cell cytokines, costimulatory receptor, and apoptotic) and adaptive (CD4(+) T-cell proliferative and memory interleukin 17A) responses. CONCLUSION: Our findings demonstrate that PLYa has the potential to manipulate host immunity irrespective of capsule type. PLY exchange between STs expressing PLYa and PLYh could lead to unexpected colonization or invasion phenotypes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Evasão da Resposta Imune , Streptococcus pneumoniae/imunologia , Estreptolisinas/imunologia , Fatores de Virulência/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Camundongos Endogâmicos C57BL , Sorogrupo , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/patogenicidade , Estreptolisinas/genética
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