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1.
Int J Infect Dis ; 146: 107147, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945433

RESUMO

OBJECTIVES: The emergence of new SARS-CoV-2 variants has led to the development of Omicron-targeting bivalent mRNA vaccines. It is crucial to understand how bivalent vaccines may improve antibody responses against new variants. METHODS: A total of 107 participants, who had three COVID-19 WT mRNA vaccine doses, were recruited, and given either a monovalent (WT) or a bivalent mRNA vaccination (Pfizer/BioNTech Bivalent (WT and BA.4/BA.5) or Moderna Bivalent (WT and BA.1). Blood samples were taken before booster and at 28 days post-booster. RESULTS: We found significantly lower fold change in serum binding IgA responses against BA.1, BA.5 and EG.5.1 spike in the bivalent booster group, compared with the monovalent (WT) booster group, following vaccination. However, this was only observed in individuals with prior infection. The relative fold change in serum binding IgA response was more skewed towards WT over variant (BA.1, BA.5 or EG.5.1) spike in previously infected bivalent-booster-vaccinees, as compared with previously infected monovalent-(WT)-booster-vaccinees. CONCLUSION: The findings suggest imprinting of antibody responses that is shaped by the first vaccination (WT spike). Previous infection also affects the boosting effect of follow-up vaccination. Studies are needed to understand how to induce a robust and long-lasting IgA immunity for protection against COVID-19 infection.

2.
Plast Reconstr Surg Glob Open ; 12(2): e5609, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348464

RESUMO

Background: Tamoxifen is a known inhibitor of fibroblast transforming growth factor beta biosynthesis and wound scar formation. Tamoxifen is also known to be an estrogen antagonist and protein kinase C (PKC) inhibitor. Cells treated with tamoxifen and other PKC/calmodulin inhibitors depolymerize their membrane focal adhesion complexes and cytoskeletal protein structures. These effects result in substrate detachment, cell shape rounding, and upregulation of collagenase synthesis and extracellular matrix degradation. The purpose of our study was to test the hypothesis that tamoxifen treatment of human foreskin fibroblasts results in alteration of cytoskeletal protein organization, cell detachment and rounding, and increased collagenase synthesis similar to known PKC/calmodulin inhibitors such as H-7. Methods: We characterized the effects of PKC/calmodulin inhibitors tamoxifen and H-7 on human dermal fibroblast morphology, cytoskeletal protein organization, and collagenase gene expression in monolayer culture and within collagen gels. Results: We found that fibroblasts responded to tamoxifen by initiation of actin filament depolymerization followed by alteration from spindle to spheroidal shapes. This change in cell shape led to increased collagenase synthesis in cells treated with either tamoxifen or H-7 compared with controls. There was also a 23% increase of hydroxyproline release from tamoxifen-treated fibroblast-populated collagen matrices. Conclusions: Tamoxifen may reduce scarring by inhibiting fibroblast PKC/calmodulin activity, which down-regulates pro-fibrotic transforming growth factor beta signaling and upregulates collagenase production. These effects mimic those of the known PKC/calmodulin inhibitor H-7. Overall, these findings suggest that tamoxifen and its analogues are promising agents for clinical investigation as small molecule regulators of fibrosis and scarring disorders.

4.
Arch Dermatol Res ; 316(1): 55, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112896

RESUMO

Sebaceous carcinoma (SC) is a very rare and aggressive form of skin cancer that arises from the sebaceous glands. SC can occur anywhere on the body, but most commonly affects the head and neck, especially the upper eyelid. SC is the third most common malignancy of the eyelid and has the potential to metastasize and be fatal; therefore, it is vital for dermatologists to remain acquainted with this malignancy and its most current treatment options. Most commonly presenting as a painless lump or thickening of skin on the eyelid, SC has an insidious progression that may not prompt the patient to seek medical attention immediately. To avoid the potential of metastasis, early diagnosis and treatment is paramount. To assess if the cancer has spread, ophthalmology, imaging, and sentinel lymph node biopsy are recommended. This article provides a comprehensive review of SC's pathogenesis, current diagnostic methods, and treatments, including wide local excision, Mohs micrographic surgery, orbital exenteration, radiation, and other topicals. The prognosis of SC depends on several factors, including size, location, stage, and treatment method. After treatment of the neoplasm, diligent post-treatment surveillance remains the cornerstone of patient care. Continued dermatologic follow-ups are essential for early detection of reoccurrence, ensuring timely intervention and optimal long-term outcomes. In conclusion, this comprehensive review aims to equip dermatologists and other physicians with a nuanced understanding of SC, enabling them to provide effective care to support patients encountering this malignancy.


Assuntos
Adenocarcinoma Sebáceo , Neoplasias das Glândulas Sebáceas , Humanos , Adenocarcinoma Sebáceo/diagnóstico , Adenocarcinoma Sebáceo/terapia , Adenocarcinoma Sebáceo/patologia , Neoplasias das Glândulas Sebáceas/diagnóstico , Neoplasias das Glândulas Sebáceas/terapia , Neoplasias das Glândulas Sebáceas/patologia , Prognóstico , Biópsia de Linfonodo Sentinela/efeitos adversos , Cirurgia de Mohs/efeitos adversos
5.
Sci Rep ; 13(1): 19331, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935965

RESUMO

Identification of the risk factors and the high-risk groups which are most vulnerable is critical in COVID-19 disease management at a population level. Evaluating the efficacy of vaccination against infections is necessary to determine booster vaccination strategies for better protection in high-risk groups. In this study, we recruited 158 mRNA-vaccinated individuals during the Delta wave of SARS-CoV-2 infections in Singapore and examined the antibody profiles of infected individuals. We found that, despite high exposure due to communal living conditions in proximity, 4% of individuals (6/158) had PCR-confirmed infections and 96% (152/158) remained uninfected. Time-course analysis of the antibody profile at the start and the end of quarantine period showed Delta-specific boosting of anti-spike antibody response in 57% of the uninfected individuals (86/152). In the remaining 43% of the uninfected individuals (66/152) with no Delta-specific antibody boost, we found a higher Delta-specific antibody response at the start of quarantine period, which correlated with higher Delta pseudovirus neutralizing capacity. Our findings indicate that a higher basal variant-specific antibody response in the mRNA-vaccinated individuals contributes to better protection against infections by the new emerging SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , RNA Mensageiro/genética , Vacinação , Vacinas de mRNA , Anticorpos Antivirais
6.
J Infect Dis ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996071

RESUMO

BACKGROUND: The emergence of rapidly evolving SARS-CoV-2 variants, coupled with waning vaccine-induced immunity, has contributed to the rise of vaccine breakthrough infections. It is crucial to understand how vaccine-induced protection is mediated. METHODS: We examined two prospective cohorts of mRNA-vaccinated-and-boosted individuals during the Omicron wave of infection in Singapore. RESULTS: We found that, individuals, who remain uninfected over the follow-up period, had a higher variant-specific IgA, but not IgG, antibody response at 1-month post booster vaccination, compared with individuals who became infected. CONCLUSIONS: We conclude that IgA may have a potential contributory role in protection against Omicron infection.

7.
Nurse Pract ; 48(11): 9-14, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37884016
8.
Sci Rep ; 13(1): 17312, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828124

RESUMO

To assess and analyse the knowledge of recommended antibiotic treatments, focusing on the appropriate drugs and treatment durations for the most common community-acquired infections in general medical practice in Occitanie region, France. A web-based survey was conducted over a 3-month period, from October, 2018 to January, 2019. All participants answered directly through the online platform. For the analysis of overtreatment risk, a score based system was adopted and two scores were produced: the duration score and the treatment score. 413 general practitioners completed the survey. The overall rate of concordance with guidelines in terms of both drug choice and treatment length was 2974/4956 (60%) answers. Diseases with at least 70% good answers included cystitis, group A streptococcal pharyngitis, and bacterial superficial skin infections. Diseases with fewer than 50% good answers included pyelonephritis, dog bite wounds, and community-acquired pneumonia in patients aged ≥ 65 years. Factors associated with the risk of overtreatment were age > 40 years, country setting and hospital employment. Knowledge of treatment durations is satisfactory with 60% of recommendations being met. However, varying levels were observed according to different diseases. This study highlighted a very high rate of adherence when recommendations were clear. In contrast, low levels of adherence were observed when recommendations were ambiguous or when conflicting guidelines existed.


Assuntos
Infecções Comunitárias Adquiridas , Faringite , Dermatopatias Bacterianas , Animais , Cães , Humanos , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/epidemiologia , Estudos Transversais , França/epidemiologia , Dermatopatias Bacterianas/tratamento farmacológico , Idoso
10.
Nat Methods ; 20(4): 512-522, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36823332

RESUMO

In response to the emergence of SARS-CoV-2 variants of concern, the global scientific community, through unprecedented effort, has sequenced and shared over 11 million genomes through GISAID, as of May 2022. This extraordinarily high sampling rate provides a unique opportunity to track the evolution of the virus in near real-time. Here, we present outbreak.info , a platform that currently tracks over 40 million combinations of Pango lineages and individual mutations, across over 7,000 locations, to provide insights for researchers, public health officials and the general public. We describe the interpretable visualizations available in our web application, the pipelines that enable the scalable ingestion of heterogeneous sources of SARS-CoV-2 variant data and the server infrastructure that enables widespread data dissemination via a high-performance API that can be accessed using an R package. We show how outbreak.info can be used for genomic surveillance and as a hypothesis-generation tool to understand the ongoing pandemic at varying geographic and temporal scales.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Genômica , Surtos de Doenças , Mutação
11.
J Int Neuropsychol Soc ; 29(1): 35-45, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35039108

RESUMO

OBJECTIVE: Electrical injury (EI) is a significant, multifaceted trauma often with multi-domain cognitive sequelae, even when the expected current path does not pass through the brain. Chronic pain (CP) research suggests pain may affect cognition directly and indirectly by influencing emotional distress which then impacts cognitive functioning. As chronic pain may be critical to understanding EI-related cognitive difficulties, the aims of the current study were: examine the direct and indirect effects of pain on cognition following EI and compare the relationship between pain and cognition in EI and CP populations. METHOD: This cross-sectional study used data from a clinical sample of 50 patients with EI (84.0% male; Mage = 43.7 years) administered standardized measures of pain (Pain Patient Profile), depression, and neurocognitive functioning. A CP comparison sample of 93 patients was also included. RESULTS: Higher pain levels were associated with poorer attention/processing speed and executive functioning performance among patients with EI. Depression was significantly correlated with pain and mediated the relationship between pain and attention/processing speed in patients with EI. When comparing the patients with EI and CP, the relationship between pain and cognition was similar for both clinical groups. CONCLUSIONS: Findings indicate that pain impacts mood and cognition in patients with EI, and the influence of pain and its effect on cognition should be considered in the assessment and treatment of patients who have experienced an electrical injury.


Assuntos
Dor Crônica , Traumatismos por Eletricidade , Humanos , Masculino , Adulto , Feminino , Estudos Transversais , Traumatismos por Eletricidade/psicologia , Cognição , Função Executiva , Testes Neuropsicológicos
13.
Front Immunol ; 13: 1031852, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451833

RESUMO

The emergence of new SARS-CoV-2 variants, such as the more transmissible Delta and Omicron variants, has raised concerns on efficacy of the COVID-19 vaccines. Here, we examined the waning of antibody responses against different variants following primary and booster vaccination. We found that antibody responses against variants were low following primary vaccination. The antibody response against Omicron was almost non-existent. Efficient boosting of antibody response against all variants, including Omicron, was observed following a third dose. The antibody response against the variants tested was significantly higher at one month following booster vaccination, compared with two months following primary vaccination, for all individuals, including the low antibody responders identified at two months following primary vaccination. The antibody response, for all variants tested, was significantly higher at four months post booster than at five months post primary vaccination, and the proportion of low responders remained low (6-11%). However, there was significant waning of antibody response in more than 95% of individuals at four months, compared to one month following booster. We also observed a robust memory B cell response following booster, which remained higher at four months post booster than prior to booster. However, the memory B cell responses were on the decline for 50% of individuals at four months following booster. Similarly, while the T cell response is sustained, at cohort level, at four months post booster, a substantial proportion of individuals (18.8 - 53.8%) exhibited T cell response at four months post booster that has waned to levels below their corresponding levels before booster. The findings show an efficient induction of immune response against SARS-CoV-2 variants following booster vaccination. However, the induced immunity by the third BNT162b2 vaccine dose was transient. The findings suggest that elderly individuals may require a fourth dose to provide protection against SARS-CoV-2.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Idoso , Humanos , Vacina BNT162 , SARS-CoV-2 , COVID-19/prevenção & controle , Anticorpos
14.
mBio ; 13(6): e0254022, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36300929

RESUMO

Airborne transmission in ferrets is a key component of pandemic risk assessment. However, some emerging avian influenza viruses transmit between ferrets but do not spread in humans. Therefore, we evaluated sequential rounds of airborne transmission as an approach to enhance the predictive accuracy of the ferret model. We reasoned that infection of ferrets via the respiratory route and onward transmission would more closely model transmission in humans. We hypothesized that pandemic and seasonal viruses would transmit efficiently over two rounds of transmission, while emerging avian viruses would fail to transmit in a second round. The 2009 pandemic H1N1 (pdm09) and seasonal H3N2 viruses were compared to avian-origin H7N9 and H3N8 viruses. Depending on the virus strain, transmission efficiency varied from 50 to 100% during the first round of transmission; the efficiency for each virus did not change during the second round, and viral replication kinetics in both rounds of transmission were similar. Both the H1N1pdm09 and H7N9 viruses acquired specific mutations during sequential transmission, while the H3N2 and H3N8 viruses did not; however, a global analysis of host-adaptive mutations revealed that minimal changes were associated with transmission of H1N1 and H3N2 viruses, while a greater number of changes occurred in the avian H3N8 and H7N9 viruses. Thus, influenza viruses that transmit in ferrets maintain their transmission efficiency through serial rounds of transmission. This answers the question of whether ferrets can propagate viruses through more than one round of airborne transmission and emphasizes that transmission in ferrets is necessary but not sufficient to infer transmissibility in humans. IMPORTANCE Airborne transmission in ferrets is used to gauge the pandemic potential of emerging influenza viruses; however, some emerging influenza viruses that transmit between ferrets do not spread between humans. Therefore, we evaluated sequential rounds of airborne transmission in ferrets as a strategy to enhance the predictive accuracy of the ferret model. Human influenza viruses transmitted efficiently (>83%) over two rounds of airborne transmission, demonstrating that, like humans, ferrets infected by the respiratory route can propagate the infection onward through the air. However, emerging avian influenza viruses with associated host-adaptive mutations also transmitted through sequential transmission. Thus, airborne transmission in ferrets is necessary but not sufficient to infer transmissibility in humans, and sequential transmission did not enhance pandemic risk assessment.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N8 , Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Infecções por Orthomyxoviridae , Humanos , Animais , Furões , Vírus da Influenza A Subtipo H3N2 , Subtipo H7N9 do Vírus da Influenza A/genética , Aves
15.
Clin Transl Immunology ; 11(8): e1403, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016852

RESUMO

Objective: Despite the high vaccine efficacy of mRNA COVID-19 vaccines, there are individuals who developed excessive reactogenic and/or allergic responses after the first mRNA dose and were considered ineligible for further mRNA doses. CoronaVac, an inactivated SARS-CoV-2 vaccine, is recommended in Singapore as an alternative. Methods: Individuals, ineligible for further mRNA vaccines (BNT162b2 or mRNA-1273) because of excessive reactive responses to prime mRNA vaccination, were recruited and offered two doses of CoronaVac as booster vaccination 38-224 days post their mRNA vaccine dose. Individuals who did not develop any excessive reactive responses after the prime mRNA vaccination were also recruited and given another mRNA vaccine as booster vaccination. Blood samples were collected at days 0, 21 and 90 post first CoronaVac dose and mRNA dose, respectively, for analysis. Results: We showed that two CoronaVac booster doses induced specific immunity in these mRNA vaccine-primed individuals. Although the spike-specific antibody response was lower, their memory B cell response against the receptor-binding domain (RBD) of the spike protein was similar, compared with individuals who received two BNT162b2 injections. The spike-specific memory T cell response also increased following CoronaVac booster doses. However, specific immunity against the Omicron variant was low, similar to individuals with two BNT162b2 doses. Conclusion: Our findings showed that while mRNA vaccine-primed individuals can opt for two subsequent doses of CoronaVac, an additional dose may be necessary to achieve protection, especially against newly emerging immune escape variants such as Omicron.

16.
PLoS Biol ; 20(8): e3001769, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35998195

RESUMO

We propose a novel, non-discriminatory classification of monkeypox virus diversity. Together with the World Health Organization, we named three clades (I, IIa and IIb) in order of detection. Within IIb, the cause of the current global outbreak, we identified multiple lineages (A.1, A.2, A.1.1 and B.1) to support real-time genomic surveillance.


Assuntos
Monkeypox virus , Mpox , Surtos de Doenças , Genômica , Humanos , Mpox/diagnóstico , Mpox/epidemiologia , Monkeypox virus/genética
17.
Res Sq ; 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35794893

RESUMO

The emergence of SARS-CoV-2 variants of concern has prompted the need for near real-time genomic surveillance to inform public health interventions. In response to this need, the global scientific community, through unprecedented effort, has sequenced and shared over 11 million genomes through GISAID, as of May 2022. This extraordinarily high sampling rate provides a unique opportunity to track the evolution of the virus in near real-time. Here, we present outbreak.info, a platform that currently tracks over 40 million combinations of PANGO lineages and individual mutations, across over 7,000 locations, to provide insights for researchers, public health officials, and the general public. We describe the interpretable and opinionated visualizations in the variant and location focussed reports available in our web application, the pipelines that enable the scalable ingestion of heterogeneous sources of SARS-CoV-2 variant data, and the server infrastructure that enables widespread data dissemination via a high performance API that can be accessed using an R package. We present a case study that illustrates how outbreak.info can be used for genomic surveillance and as a hypothesis generation tool to understand the ongoing pandemic at varying geographic and temporal scales. With an emphasis on scalability, interactivity, interpretability, and reusability, outbreak.info provides a template to enable genomic surveillance at a global and localized scale.

18.
Vaccines (Basel) ; 10(6)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35746515

RESUMO

Seasonal Influenza H3N2 virus poses a great threat to public health, but its vaccine efficacy remains suboptimal. One critical step in influenza vaccine production is the viral passage in embryonated eggs. Recently, the strength of egg passage adaptation was found to be rapidly increasing with time driven by convergent evolution at a set of functionally important codons in the hemagglutinin (HA1). In this study, we aim to take advantage of the negative correlation between egg passage adaptation and vaccine effectiveness (VE) and develop a computational tool for selecting the best candidate vaccine virus (CVV) for vaccine production. Using a probabilistic approach known as mutational mapping, we characterized the pattern of sequence evolution driven by egg passage adaptation and developed a new metric known as the adaptive distance (AD) which measures the overall strength of egg passage adaptation. We found that AD is negatively correlated with the influenza H3N2 vaccine effectiveness (VE) and ~75% of the variability in VE can be explained by AD. Based on these findings, we developed a computational package that can Measure the Adaptive Distance and predict vaccine Effectiveness (MADE). MADE provides a powerful tool for the community to calibrate the effect of egg passage adaptation and select more reliable strains with minimum egg-passaged changes as the seasonal A/H3N2 influenza vaccine.

19.
Phys Biol ; 19(4)2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35545073

RESUMO

To enhance the stability of protein therapeutics, pharmaceutical companies have long used various copolymer surfactants as excipients. They act to stabilize proteins by adhering to the hydrophobic surface of the protein preventing denaturation and aggregation. However, some commonly used excipients possess polyoxyalkylene chains that are susceptible to oxidative degradation while in aqueous solution. We postulate that oxidation reactions involving the hydrophobic domains reduce the surfactant's ability to stabilize the native protein structure. We investigated the effect of UV (λ = 254 nm) radiated poloxamine T1107 (T1107) on its ability to disaggregate DTT denatured hen egg-white lysozyme (HEWL). Peroxidation of UV irradiated T1107 was analyzed using FTIR spectroscopy, the Fe+2to Fe+3ion reduction assay method, and1H NMR. Our results indicate that increased UV irradiation led to structural changes in T1107, specifically the addition of a carbonyl on the formate group. The structural change decreased T1107's ability to disaggregate HEWL thus supporting our hypothesis. These results indicate that peroxide content is an important parameter to control in polyoxyalkylene-based excipients.


Assuntos
Etilenodiaminas , Excipientes , Interações Hidrofóbicas e Hidrofílicas , Tensoativos
20.
Nursing ; 52(5): 39-43, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35452040

RESUMO

ABSTRACT: The clinical spectrum of electrical injury ranges from the absence of any external physical signs to severe and life-threatening trauma. This article discusses the fundamental concepts and misunderstandings surrounding electrical injuries and the best practices for evaluation and treatment.

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