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1.
Cureus ; 16(6): e62327, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39006603

RESUMO

Introduction Neck adiposity has been related to cardiovascular risk in healthy and nonhealthy individuals. Our objective was to evaluate the utility of anatomic neck measurements extracted from computed tomography (CT) examinations as a predictor of cardiovascular disease and its risk factors. Methods We investigated patients who had a CT neck examination with intravenous contrast performed at two hospitals between 2013 and 2020. Patients with a neck malignancy, prior neck surgery, age <18 years, incomplete demographic information, and inadequate image quality were excluded. We performed 18 separate measurements of neck anatomy which were correlated with cardiovascular risk factors and disease, as well as relevant lab values and medications. All multivariable linear regressions were controlled for gender and BMI. Associations with p<0.05 were considered statistically significant. The measurements were then used to predict hypertension using random forest, a non-linear prediction algorithm. Results Approximately 20,000 neck CT examinations with contrast were performed between 2013-2020. After applying the inclusion criteria, 458 patients remained in the study population. Eight measurements (all of which include a component of neck adiposity) showed a statistically significant association between anatomic measurements and cardiovascular risk factors. The risk factor most often associated with increases in CT measurements was type 2 diabetes. Accordingly, patients on insulin treatment had a significantly higher average for all eight measurements. Significant measurement increases were also found in those previously diagnosed with hyperlipidemia and in those being treated with hypertension medications. The area under the receiver operating characteristic (AUROC) value of the random forest prediction algorithm was 0.68, meaning our measurements were a good predictor of hypertensive disease status. Conclusion Adipose tissue measurements extracted from CT examinations of the neck are associated with cardiovascular risk factors including hypertension, diabetes, and hyperlipidemia. Machine learning models of anatomic neck measurements can potentially identify patients at risk for cardiovascular disease.

2.
Elife ; 122023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38055781

RESUMO

Pyroptosis and apoptosis are two forms of regulated cell death that can defend against intracellular infection. When a cell fails to complete pyroptosis, backup pathways will initiate apoptosis. Here, we investigated the utility of apoptosis compared to pyroptosis in defense against an intracellular bacterial infection. We previously engineered Salmonella enterica serovar Typhimurium to persistently express flagellin, and thereby activate NLRC4 during systemic infection in mice. The resulting pyroptosis clears this flagellin-engineered strain. We now show that infection of caspase-1 or gasdermin D deficient macrophages by this flagellin-engineered S. Typhimurium induces apoptosis in vitro. Additionally, we engineered S. Typhimurium to translocate the pro-apoptotic BH3 domain of BID, which also triggers apoptosis in macrophages in vitro. During mouse infection, the apoptotic pathway successfully cleared these engineered S. Typhimurium from the intestinal niche but failed to clear the bacteria from the myeloid niche in the spleen or lymph nodes. In contrast, the pyroptotic pathway was beneficial in defense of both niches. To clear an infection, cells may have specific tasks that they must complete before they die; different modes of cell death could initiate these 'bucket lists' in either convergent or divergent ways.


Although alive and healthy cells are essential for survival, in certain circumstances ­ such as when a cell becomes infected ­ it is beneficial for cells to deliberately die through a process known as regulated cell death. There are several types of regulated cell death, each with distinct pathways and mechanisms. However, if the initial pathway is blocked, cells can use an alternative one, suggesting that they can compensate for one other. Two forms of regulated cell death ­ named pyroptosis and apoptosis ­ can be used by infected cells to limit the spread of pathogens. However, it was not clear if these two forms or additional 'back-up' apoptosis pathways ­ which are induced when pyroptosis fails ­ are equally efficient at clearing infections and how they might vary in different cell types. To address this, Abele et al. investigated cell death in live mice infected with the bacterium Salmonella. Different organs in which the bacterium infects distinct cell types were examined. Experiments showed that pyroptosis could eliminate bacteria from both intestinal cells as well as immune cells found throughout the body, called macrophages. In contrast, apoptosis was only able to clear infection from intestinal cells. The findings can be explained by prior studies showing both apoptosis and pyroptosis lead to the same outcome in intestinal cells ­ dead cells are expelled from the body through a process called extrusion to maintain the barrier function of the intestine. However, in macrophages, the different pathways lead to different outcomes, indicating they are not entirely interchangeable. Overall, the findings of Abele et al. underscore the complexity of cellular responses to infection and the nuanced roles of different cell death pathways. This provides further evidence that cells might have specific tasks they need to complete before death in order to effectively clear an infection. These tasks may differ depending on cell type and the form of regulated cell death, and may not be equally efficient at clearing an infection.


Assuntos
Apoptose , Flagelina , Animais , Camundongos , Morte Celular , Caspase 1/metabolismo , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Piroptose , Inflamassomos/metabolismo
3.
bioRxiv ; 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37205464

RESUMO

Pyroptosis and apoptosis are two forms of regulated cell death that can defend against intracellular infection. Although pyroptosis and apoptosis have distinct signaling pathways, when a cell fails to complete pyroptosis, backup pathways will initiate apoptosis. Here, we investigated the utility of apoptosis compared to pyroptosis in defense against an intracellular bacterial infection. We previously engineered Salmonella enterica serovar Typhimurium to persistently express flagellin, and thereby activate NLRC4 during systemic infection in mice. The resulting pyroptosis clears this flagellin-engineered strain. We now show that infection of caspase-1 or gasdermin D deficient macrophages by this flagellin-engineered S. Typhimurium induces apoptosis in vitro. Additionally, we also now engineer S. Typhimurium to translocate the pro-apoptotic BH3 domain of BID, which also triggers apoptosis in macrophages in vitro. In both engineered strains, apoptosis occurred somewhat slower than pyroptosis. During mouse infection, the apoptotic pathway successfully cleared these engineered S. Typhimurium from the intestinal niche, but failed to clear the bacteria in the myeloid niche in the spleen or lymph nodes. In contrast, the pyroptotic pathway was beneficial in defense of both niches. In order to clear an infection, distinct cell types may have specific tasks that they must complete before they die. In some cells, either apoptotic or pyroptotic signaling may initiate the same tasks, whereas in other cell types these modes of cell death may lead to different tasks that may not be identical in defense against infection. We recently suggested that such diverse tasks can be considered as different cellular 'bucket lists' to be accomplished before a cell dies.

4.
Plast Reconstr Surg ; 149(5): 1009e-1013e, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35311800

RESUMO

BACKGROUND: Plastic surgeons are often asked for intraoperative assistance by other surgical services. Improvement of a plastic surgery service has been shown to improve patient outcomes, decrease length of stay, and increase hospital revenue, yet plastic surgery's contribution to a hospital tends to be undervalued. The purpose of this study was to quantify the multidisciplinary role the plastic surgery service plays within a single, large pediatric institution. METHODS: Surgical cases involving both plastic surgery and at least one other team were identified from 2016 to 2019. Each case was categorized as either "combined" or "collaborative" based on whether the two teams worked separately on separate problems or together on the same problem, respectively. Data points collected included combined and collaborative cases, operating room hours, and total hospital charges billed. RESULTS: Of the 7564 total plastic surgery cases performed, multidisciplinary cases made up a minority of total cases (16 percent) but required 32 percent of the operating room hours and provided 49 percent of the total charges billed. Collaborative cases alone accounted for 20 percent of the service's operating room hours and 39 percent of total charges billed, while making up only 8 percent of total cases. CONCLUSIONS: Relative to cases where plastic surgery operates alone, combined and collaborative cases account for a disproportionately high number of operating room hours and provide a disproportionately high amount of charges billed.


Assuntos
Procedimentos de Cirurgia Plástica , Cirurgiões , Cirurgia Plástica , Criança , Preços Hospitalares , Humanos , Salas Cirúrgicas
5.
Can J Urol ; 28(6): 10936-10940, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34895399

RESUMO

INTRODUCTION: To present our novel low submuscular (LSM) pressure regulating balloon (PRB) placement for artificial urinary sphincter (AUS) technique as an alternative to standard approaches with patient-reported satisfaction outcomes. MATERIAL AND METHODS: A retrospective review was conducted on patients who underwent an AUS implantation using the LSM PRB placement with transfascial fixation technique from July 2019 to August 2020. Preoperative characteristics were collected. Patients then conducted a postoperative phone interview using an adapted questionnaire to assess satisfaction of device and PRB concealment. RESULTS: During the study period, nine patients had undergone AUS placement using the LSM technique by a single surgeon at our private institution. Eight of the nine patients had undergone a radical prostatectomy while the ninth patient developed stress urinary incontinence after radiation treatment for prostate cancer. All patients were 'very satisfied' with PRB placement and concealment with no patients endorsing PRB complications. The majority of patients (78%) were satisfied with the device. One patient was able to palpate the PRB while another patient endorsed mild soreness around the PRB. No surgical revisions were required and there were no surgical complications such as bowel obstruction, herniations, bladder erosions, or vascular injuries. CONCLUSION: LSM placement of AUS PRB with transfascial fixation offers an improved technique for balloon placement with decreased risk for complications. This can be performed as a safe, alternative approach to current standard techniques with a high degree of patient satisfaction.


Assuntos
Incontinência Urinária por Estresse , Esfíncter Urinário Artificial , Humanos , Masculino , Prostatectomia/efeitos adversos , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/cirurgia , Esfíncter Urinário Artificial/efeitos adversos
6.
Eur J Immunol ; 46(12): 2761-2766, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27682622

RESUMO

Inflammasomes activate caspase-1, initiating a lytic form of programmed cell death termed pyroptosis, which is an important innate immune defense mechanism against intracellular infections. We recently demonstrated in a mouse infection model of pyroptosis that instead of releasing bacteria into the extracellular space, bacteria remain trapped within the pyroptotic cell corpse, termed the pore-induced intracellular trap (PIT). This trapping mediates efferocytosis of the PIT and associated bacteria by neutrophils; bacteria are subsequently killed via neutrophil ROS. Using this pyroptosis model, we now show that the pro-inflammatory cytokines IL-1ß and IL-18 and inflammatory lipid mediators termed eicosanoids are required for effective clearance of bacteria downstream of pyroptosis. We further show that IL-1ß, IL-18, and eicosanoids affect this in part by mediating neutrophil recruitment to the PIT. This is in addition to our prior findings that complement is also important to attract neutrophils. Thus, the PIT initiates a robust and coordinated innate immune response involving multiple mediators that attract neutrophils to efferocytose the PIT and its entrapped bacteria.


Assuntos
Infecções por Bactérias Gram-Positivas/imunologia , Neutrófilos/imunologia , Salmonella enterica/imunologia , Animais , Caspase 1/metabolismo , Movimento Celular , Células Cultivadas , Eicosanoides/metabolismo , Armadilhas Extracelulares/imunologia , Imunidade Inata , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Porinas/metabolismo , Piroptose , Espécies Reativas de Oxigênio/metabolismo
7.
Respir Res ; 10: 60, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19566962

RESUMO

BACKGROUND: Surfactant protein A (SP-A) is a C-type lectin involved in surfactant homeostasis as well as host defense in the lung. We have recently demonstrated that SP-A enhances the killing of bacillus Calmette-Guerin (BCG) by rat macrophages through a nitric oxide-dependent pathway. In the current study we have investigated the role of tyrosine kinases and the downstream mitogen-activated protein kinase (MAPK) family, and the transcription factor NFkappaB in mediating the enhanced signaling in response to BCG in the presence of SP-A. METHODS: Human SP-A was prepared from alveolar proteinosis fluid, and primary macrophages were obtained by maturation of cells from whole rat bone marrow. BCG-SP-A complexes were routinely prepared by incubation of a ratio of 20 microg of SP-A to 5 x 105 BCG for 30 min at 37 degrees C. Cells were incubated with PBS, SP-A, BCG, or SP-A-BCG complexes for the times indicated. BCG killing was assessed using a 3H-uracil incorporation assay. Phosphorylated protein levels, enzyme assays, and secreted mediator assays were conducted using standard immunoblot and biochemical methods as outlined. RESULTS: Involvement of tyrosine kinases was demonstrated by herbimycin A-mediated inhibition of the SP-A-enhanced nitric oxide production and BCG killing. Following infection of macrophages with BCG, the MAPK family members ERK1 and ERK2 were activated as evidence by increased tyrosine phosphorylation and enzymatic activity, and this activation was enhanced when the BCG were opsonized with SP-A. An inhibitor of upstream kinases required for ERK activation inhibited BCG- and SP-A-BCG-enhanced production of nitric oxide by approximately 35%. Macrophages isolated from transgenic mice expressing a NFkappaB-responsive luciferase gene showed increased luciferase activity following infection with BCG, and this activity was enhanced two-fold in the presence of SP-A. Finally, lactacystin, an inhibitor of IkappaB degradation, reduced BCG- and SP-A-BCG-induced nitric oxide production by 60% and 80% respectively. CONCLUSION: These results demonstrate that BCG and SP-A-BCG ingestion by macrophages is accompanied by activation of signaling pathways involving the MAP kinase pathway and NFkappaB.


Assuntos
Macrófagos/fisiologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Mycobacterium bovis , NF-kappa B/fisiologia , Proteína A Associada a Surfactante Pulmonar/farmacologia , Animais , Benzoquinonas/farmacologia , Western Blotting , Células da Medula Óssea/fisiologia , Ensaio de Desvio de Mobilidade Eletroforética , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Imunoprecipitação , Lactamas Macrocíclicas/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Óxido Nítrico/biossíntese , Fagocitose/efeitos dos fármacos , Proteína A Associada a Surfactante Pulmonar/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Rifabutina/análogos & derivados
8.
J Leukoc Biol ; 74(4): 523-30, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12960270

RESUMO

Mycobacterium avium complex (MAC) is a significant cause of opportunistic infection in patients with acquired immunodeficiency syndrome. Although the major route of entry of MAC is via the gastrointestinal tract, MAC can infect humans through the respiratory tract and eventually encounter alveolar macrophages within the lung. Once in the lung, MAC can potentially interact with surfactant protein A (SP-A), an important component of the pulmonary innate-immune response. Previous work on other pulmonary pathogens including Mycobacterium bovis Bacillus Calmette-Guerin (BCG) suggests that SP-A participates in promoting efficient clearance of these organisms by alveolar macrophages. In the present study, we investigated the role of SP-A in clearance of MAC by cultured rat macrophages. SP-A bound to MAC organisms and enhanced the ingestion of the mycobacteria by macrophages. Infection of macrophages with SP-A-MAC complexes induced the production of nitric oxide (NO) and tumor necrosis factor-alpha. However, intracellular survival of MAC was not altered by preopsonization with SP-A. In addition, inhibitors of inducible NO synthase did not alter MAC clearance. These results suggest that SP-A can bind to and enhance the uptake of MAC by alveolar macrophages, similar to previous findings with BCG and Mycobacterium tuberculosis.However, unlike BCG and other pulmonary pathogens that are cleared effectively in the presence of SP-A via a NO-dependent pathway, macrophage-mediated clearance of MAC is not enhanced by SP-A.


Assuntos
Macrófagos/imunologia , Complexo Mycobacterium avium/imunologia , Proteína A Associada a Surfactante Pulmonar/farmacologia , Animais , Macrófagos/microbiologia , Óxido Nítrico/fisiologia , Fagocitose , Ratos , Fator de Necrose Tumoral alfa/fisiologia
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