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1.
mBio ; : e0129224, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860823

RESUMO

Sepsis and chronic infections with Pseudomonas aeruginosa, a leading "ESKAPE" bacterial pathogen, are associated with increased morbidity and mortality and skeletal muscle atrophy. The actions of this pathogen on skeletal muscle remain poorly understood. In skeletal muscle, mitochondria serve as a crucial energy source, which may be perturbed by infection. Here, using the well-established backburn and infection model of murine P. aeruginosa infection, we deciphered the systemic impact of the quorum-sensing transcription factor MvfR (multiple virulence factor regulator) by interrogating, 5 days post-infection, its effect on mitochondrial-related functions in the gastrocnemius skeletal muscle and the outcome of the pharmacological inhibition of MvfR function and that of the mitochondrial-targeted peptide, Szeto-Schiller 31 (SS-31). Our findings show that the MvfR perturbs adenosine triphosphate generation, oxidative phosphorylation, and antioxidant response, elevates the production of reactive oxygen species, and promotes oxidative damage of mitochondrial DNA in the gastrocnemius muscle of infected mice. These impairments in mitochondrial-related functions were corroborated by the alteration of key mitochondrial proteins involved in electron transport, mitochondrial biogenesis, dynamics and quality control, and mitochondrial uncoupling. Pharmacological inhibition of MvfR using the potent anti-MvfR lead, D88, we developed, or the mitochondrial-targeted peptide SS-31 rescued the MvfR-mediated alterations observed in mice infected with the wild-type strain PA14. Our study provides insights into the actions of MvfR in orchestrating mitochondrial dysfunction in the skeletal murine muscle, and it presents novel therapeutic approaches for optimizing clinical outcomes in affected patients. IMPORTANCE: Skeletal muscle, pivotal for many functions in the human body, including breathing and protecting internal organs, contains abundant mitochondria essential for maintaining cellular homeostasis during infection. The effect of Pseudomonas aeruginosa (PA) infections on skeletal muscle remains poorly understood. Our study delves into the role of a central quorum-sensing transcription factor, multiple virulence factor regulator (MvfR), that controls the expression of multiple acute and chronic virulence functions that contribute to the pathogenicity of PA. The significance of our study lies in the role of MvfR in the metabolic perturbances linked to mitochondrial functions in skeletal muscle and the effectiveness of the novel MvfR inhibitor and the mitochondrial-targeted peptide SS-31 in alleviating the mitochondrial disturbances caused by PA in skeletal muscle. Inhibiting MvfR or interfering with its effects can be a potential therapeutic strategy to curb PA virulence.

2.
bioRxiv ; 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38746243

RESUMO

Sepsis and chronic infections with Pseudomonas aeruginosa, a leading "ESKAPE" bacterial pathogen, are associated with increased morbidity and mortality and skeletal muscle atrophy. The actions of this pathogen on skeletal muscle remain poorly understood. In skeletal muscle, mitochondria serve as a crucial energy source, which may be perturbed by infection. Here, using the well-established backburn and infection model of murine P. aeruginosa infection, we deciphered the systemic impact of the quorum sensing (QS) transcription factor MvfR by interrogating five days post-infection its effect on mitochondrial-related functions in the gastrocnemius skeletal muscle and the outcome of the pharmacological inhibition of MvfR function and that of the mitochondrial-targeted peptide, Szeto-Schiller 31 (SS-31). Our findings show that the MvfR perturbs ATP generation, oxidative phosphorylation (OXPHOS), and antioxidant response, elevates the production of reactive oxygen species, and promotes oxidative damage of mitochondrial DNA in the gastrocnemius muscle of infected mice. These impairments in mitochondrial-related functions were corroborated by the alteration of key mitochondrial proteins involved in electron transport, mitochondrial biogenesis, dynamics and quality control, and mitochondrial uncoupling. Pharmacological inhibition of MvfR using the potent anti-MvfR lead, D88, we developed, or the mitochondrial-targeted peptide SS-31 rescued the MvfR- mediated alterations observed in mice infected with the wild-type strain PA14. Our study provides insights into the actions of MvfR in orchestrating mitochondrial dysfunction in the skeletal murine muscle, and it presents novel therapeutic approaches for optimizing clinical outcomes in affected patients.

3.
Chem Commun (Camb) ; 58(83): 11705-11708, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36178029

RESUMO

Using a Lewis acid-quenched CF2Ph- reagent, we show C-C bond formation through nucleophilic addition reactions to prepare molecules containing internal -CF2- linkages. We demonstrate C(sp2)-C(sp3) coupling using both SNAr reactions and Pd-catalysis. Finally, C(sp3)-C(sp3) bonds are forged using operationally simple SN2 reactions that tolerate medicinally-relevant motifs.


Assuntos
Ácidos de Lewis , Compostos de Boro , Catálise , Indicadores e Reagentes
4.
Dent Traumatol ; 38(6): 505-511, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35972842

RESUMO

BACKGROUND/AIM: Complicated crown fractures are frequently encountered in the paediatric population and pulpotomy procedures (either partial or coronal) are recommended to maintain the pulp. The aim of this study was to determine the pulp outcomes of permanent teeth with complicated crown fractures treated with pulpotomy in a hospital-setting and to identify potential factors which may influence the outcomes. MATERIAL AND METHODS: Data for this retrospective study were extracted from dental records of patients with complicated crown fractures and treated with pulpotomies at a single centre between 1 January 2015 and 30 August 2019. Pulp outcomes were determined, and the associations between the outcome and independent variables were assessed using the Chi-Square test of independence and the Point-Biserial Correlation Test. Predictors of outcome were identified using the binary logistic regression model. RESULTS: The overall success of pulpotomy in managing traumatised permanent teeth was 61%, which was lower than those previously reported. Pulp healing was seen in 54.1% and 73.7% of teeth treated with partial pulpotomies and coronal pulpotomies, respectively. The presence of a radiographically detectable dentine bridge (p < .01) and longer clinical experience of the clinician (p < .04) was significantly associated with successful outcomes. The history of pain and the stage of root development were identified as significant predictors of the outcome. CONCLUSION: Pulpotomy is a viable treatment modality for complicated crown fractures in the paediatric population. However, appropriate case selection and further training may be required to ensure improved pulp healing outcomes. A longer follow-up period should be considered to identify late-stage complications.


Assuntos
Pulpotomia , Fraturas dos Dentes , Humanos , Criança , Pulpotomia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Exposição da Polpa Dentária/etiologia , Dentição Permanente , Fraturas dos Dentes/terapia
5.
J Endod ; 47(9): 1507-1514, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34058251

RESUMO

The aim of this case series was to describe the endodontic management of 3 immature permanent teeth that sustained traumatic injuries and subsequently presented with complete ingrowth of mineralized tissue into the canal space. Ingrowth of bone/mineralized tissue into the canal has been considered a poor long-term outcome with an inherent risk of ankylosis. In cases 1 and 2, no endodontic treatment was undertaken, except for emergency management requiring splinting. The cases were followed for 36 and 23 months, respectively. No ankylosis was evident over the review period, and normal teeth eruption was apparent. In case 1, the tooth was treated orthodontically and was responsive to pulp sensibility testing. In both cases, there was an appearance of an internal periodontal ligament-like space on the inner root wall of the canal. In case 3, 2 years postinjury, pulp necrosis and apical periodontitis occurred, and the tooth was managed with regenerative endodontic treatment consistent with the European Society of Endodontology and the American Association of Endodontists guidelines/recommendations for a regenerative procedure. The case was followed for 8 years after regenerative endodontic treatment. No ankylosis was noted with normal eruption of the teeth. The tooth was responsive to pulp sensibility testing despite the ingrowth of mineralized tissue, which was confirmed clinically.


Assuntos
Periodontite Periapical , Anquilose Dental , Cavidade Pulpar , Necrose da Polpa Dentária/etiologia , Necrose da Polpa Dentária/terapia , Humanos , Tratamento do Canal Radicular , Anquilose Dental/etiologia , Anquilose Dental/terapia
6.
Surgery ; 168(1): 155-159, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32493616

RESUMO

BACKGROUND: Neuropeptide Y acts directly on the vasculature as a cotransmitter with norepinephrine for an augmented contraction. Little, however, is known about the effects of neuropeptide Y on the microvasculature of human skeletal muscle. Neuropeptide Y signaling has not been studied in the setting of cardiac surgery and cardiopulmonary bypass. We investigated the role of neuropeptide Y signaling on vasomotor tone in the microvessels of human skeletal muscle, as well as the effect of cardiopulmonary bypass on neuropeptide Y-induced responsiveness. METHODS: Specimens taken from intercostal muscles were collected from patients, pre- and post-cardiopulmonary bypass, undergoing coronary artery bypass grafting or cardiac valve surgery (n = 8/group). Microvessels (157 ± 47 microns) were isolated in vitro in a no-flow state. Arterial microvascular responses to a neuropeptide Y agonist, a Y1 receptor antagonist, phenylephrine, and the coadministration of neuropeptide Y and phenylephrine were examined. The abundance and localization of the Y1 receptor were measured using Western blot and immunofluorescence, respectively. RESULTS: Arterial microvessels showed responsiveness to the neuropeptide Y agonist (10-9 to 4 × 10-7 mol/L) both before and after cardiopulmonary bypass, reaching a 12.5% vasoconstriction from the baseline luminal diameter. With administration of the Y1 receptor antagonist after neuropeptide Y, the contractile response was eliminated (n = 3/group, P = .04). No difference in vasoconstriction was observed between pre- and post-cardiopulmonary bypass groups (P = .73). The coadministration of neuropeptide Y and phenylephrine (10-9 to 10-4 mol/L) elicited no difference in vasoconstriction (n = 7/group, P = .06 both pre- and post-cardiopulmonary bypass) when compared with phenylephrine alone (10-9 to 10-4 mol/L). No change in the protein expression or localization of the Y1 receptor was detected by Western blotting (n = 6/group, P = .44) or immunofluorescence (n = 6/group, P = .13). CONCLUSION: Neuropeptide Y induced vasoconstriction, suggesting that neuropeptide Y may play an important role in the regulation of the peripheral microvasculature. There was no change in microvascular responsiveness to neuropeptide Y after cardiopulmonary bypass nor were there any synergistic effects of neuropeptide Y on phenylephrine-induced vasoconstriction in the skeletal muscle microvasculature.


Assuntos
Ponte Cardiopulmonar , Microvasos/fisiologia , Neuropeptídeo Y/fisiologia , Vasoconstrição , Idoso , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea
7.
Food Res Int ; 99(Pt 1): 755-761, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28784541

RESUMO

The baobab (Adansonia digitata L.) is a magnificent tree revered throughout Africa and is becoming recognized for its high nutritional and medicinal values. Despite numerous reports on the pharmacological potential, little is known about its chemical compositions. In this study, four hydroxycinnamic acid glycosides (1-4), six iridoid glycosides (5-10), and three phenylethanoid glycosides (11-13) were isolated from the dried baobab fruit pulp. Their structures were determined by means of spectroscopic analyses, including HRMS, 1H and 13C NMR and 2D experiments (COSY, HSQC, HMBC, and ROESY). All 13 compounds isolated were reported for the first time in the genus of Adansonia. An ultra high-performance liquid chromatography high-resolution accurate-mass mass spectrometry (UHPLC HRAM MS) method was used to conduct further investigation of the chemical compositions of the hydro-alcohol baobab fruit pulp extract. Hydroxycinnamic acid glycosides, iridoid glycosides and phenylethanoid glycosides were found to be the main components in baobab fruit pulp.


Assuntos
Adansonia/química , Frutas/química , Glicosídeos/análise , Glicosídeos Iridoides/análise , Extratos Vegetais/química , Ácidos Cumáricos/análise , Álcool Feniletílico/análise
8.
South Med J ; 95(1): 78-87, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11827249

RESUMO

BACKGROUND: There is a need to evaluate empirical disease management programs used in managing chronic diseases such as diabetes mellitus in managed care settings. METHODS: We analyzed data from 252 patients with type 2 diabetes before and 1 year after enrollment in a disease management program. We examined clinical indicators such as HbA1C, HDL, LDL, total cholesterol, diastolic blood pressure, and BMI in addition to self-reported health status measured by SF-36 instrument. RESULTS: All clinical indicators showed statistically and clinically significant improvements. Only vitality and mental health showed statistically significant improvements in health status. Weak to moderate significant correlation between clinical indicators and health status was observed. CONCLUSIONS: Disease management can be effective at making significant clinical improvements for participants in a mixed-model HMO setting. No strong relationship between clinical indicators and health status was found. Future research is needed using a more specific health status measuring instrument and a randomized clinical trial design.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Gerenciamento Clínico , Sistemas Pré-Pagos de Saúde , Avaliação de Resultados em Cuidados de Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Hemoglobinas Glicadas/análise , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Fatores de Tempo
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