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1.
Ann Diagn Pathol ; 70: 152283, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447254

RESUMO

INTRODUCTION: Primary pulmonary salivary gland-type tumours (PPSGT) are rare lung neoplasms arising from submucosal seromucinous glands in the central airway. METHODS AND RESULTS: We retrospectively analysed the clinicopathological features of 111 PPSGTs diagnosed at our institute between 2003 and 2021. The mean age at diagnosis was 43.8 years(range 6-78 years) and a male-to-female ratio of 2:1. On imaging, 92 % of cases had centrally located tumours and 37.3 % were early stage. The histopathological types included 70 cases (63 %) of mucoepidermoid carcinoma (MEC), 31 cases (27.7 %) of adenoid cystic carcinoma (ADCC), two cases of myoepithelial carcinoma, one case each of acinic cell carcinoma (ACC), clear cell carcinoma (CCC), epithelial myoepithelial carcinoma (EMC) and 5 others [including adenocarcinoma of minor salivary gland origin(n = 3), carcinoma with sebaceous differentiation(n = 1) and poorly differentiated carcinoma of salivary gland type(n = 1)]. The size of the tumours found in the resection specimens ranged from 1 cm to 13 cm, with an average size of 4.9 cm. High-risk attributes such as lymphovascular invasion (LVI), perineural invasion (PNI), pleural involvement, positive resection margins, and nodal metastasis were identified in 15.3 %, 15.3 %, 13.6 %,15.2 % and 6.7 % of cases, respectively. These attributes were found to be more frequent in ADCC than in MEC. Surgery was the main treatment modality [68/84 (80 %) cases]. ADCC cases had more recurrence and distant metastasis than MEC cases. The 3- year overall-survival (OS) and recurrence-free survival(RFS) were better in patients with age lesser than 60 years(p-value <0.0001), low pT stage (p-value 0.00038) and lower grade of MEC(p-value-0.0067). CONCLUSION: It is crucial to have an acquaintance with the morphologic spectrum and immunophenotypic characteristics of PPSGT to recognize them in this unusual location. In tandem, it is crucial to differentiate them from conventional primary non-small cell lung carcinoma, as the management protocols and prognostic implications differ significantly.


Assuntos
Neoplasias Pulmonares , Neoplasias das Glândulas Salivares , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Adulto , Idoso , Adolescente , Neoplasias Pulmonares/patologia , Neoplasias das Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/diagnóstico , Adulto Jovem , Criança , Carcinoma Mucoepidermoide/patologia , Carcinoma Mucoepidermoide/diagnóstico , Neoplasias Brônquicas/patologia , Neoplasias Brônquicas/diagnóstico , Carcinoma Adenoide Cístico/patologia , Carcinoma Adenoide Cístico/diagnóstico
2.
Sci Adv ; 10(13): eadk7201, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536910

RESUMO

Enzymes populate ensembles of structures necessary for catalysis that are difficult to experimentally characterize. We use time-resolved mix-and-inject serial crystallography at an x-ray free electron laser to observe catalysis in a designed mutant isocyanide hydratase (ICH) enzyme that enhances sampling of important minor conformations. The active site exists in a mixture of conformations, and formation of the thioimidate intermediate selects for catalytically competent substates. The influence of cysteine ionization on the ICH ensemble is validated by determining structures of the enzyme at multiple pH values. Large molecular dynamics simulations in crystallo and time-resolved electron density maps show that Asp17 ionizes during catalysis and causes conformational changes that propagate across the dimer, permitting water to enter the active site for intermediate hydrolysis. ICH exhibits a tight coupling between ionization of active site residues and catalysis-activated protein motions, exemplifying a mechanism of electrostatic control of enzyme dynamics.


Assuntos
Simulação de Dinâmica Molecular , Proteínas , Cristalografia por Raios X , Proteínas/química , Catálise , Conformação Proteica , Hidrolases
3.
Artigo em Inglês | MEDLINE | ID: mdl-38308686

RESUMO

PURPOSE: Esophageal cancer is among the leading causes of cancer-related mortality worldwide. Patients presenting with localized and loco-regionally advanced cancer without distant metastases have reasonable survival with multimodality management. Adequate and comprehensive staging is the backbone for proper selection of patients fit for curative treatment. Positron emission tomography (PET) in combination with contrast-enhanced computed tomography (CECT) is utilized as the standard staging modality. Multimodality treatment has been able to achieve evaluable tumor responses including pathological complete response (pCR). It is, therefore, necessary to understand whether the impact of neoadjuvant therapy can be evaluated on imaging, i.e., standardized uptake value (SUV) on PET scan done for response assessment and if this can be correlated with histopathological response and later, with survival. Squamous cell carcinoma (SCC) is more common globally and in the Indian subcontinent; hence, we chose this subgroup to evaluate our hypothesis. METHODS: This is a single institution, retrospective study. Out of the 1967 patients who were treated between 2009 and 2019, 1369 (78.54%) patients had SCC. Out of these, 44 received NACTRT, whereas 1325 received NACT followed by curative surgery. The standardized uptake value (SUV) of 18-fluorodeoxyglucose was recorded during pre- and post-neoadjuvant treatment (NAT) using positron emission tomography (PET). The histopathology of the final resection specimen was evaluated using the Mandard tumor regression grade (TRG) criteria with response being graded from 0 to 5 as no residual tumor (NRT), scanty residual tumor (SRT), and residual tumor We attempted to find a cut-off value of the post neoadjuvant SUV of the primary tumor site which correlated with achievement of better histopathological response. RESULTS: Out of 1325 patients of SCC esophagus who underwent surgery, 943 patients had available data of TRG, and it was categorized into the 0-2 category which had 325 patients (34.5%) and 3-5 category, 618 patients (65.5%). The SUV was taken only from the PET scans done at our institution, so as to achieve a more homogenous cohort, and this was available for 186 patients, 151 from the NACT group and 35 from the NACTRT group. The ROC method was used to find the cut-off for SUV (5.05) in the NACT cohort, which depicted significant difference in the outcome. Out of these, 93 patients who underwent NACT had SUV > 5.05 and 58 had SUV < 5.05. It was found that the subjective and objective histopathological scores correlated at a p value of < 0.0001. Specifically, the majority of cases with SRT tended to be in the 3-5 category of TRG, whereas cases with NRT are predominantly in the 0-2 category. In the ≥ 5.05 category of SUV, there were 76 cases with SRT. In the NACT cohort, the < 5.05 category of SUV, there are 26 cases with SRT and 32 cases with NRT. Among cases with SRT, 74.5% had SUV ≥ 5.05, while 25.5% had SUV < 5.05. Among cases with NRT, 34.7% had SUV ≥ 5.05, while 65.3% had SUV < 5.05 (p value 0.007). No significant association was found in the radio-pathological correlation in the NACTRT group. CONCLUSION: Our study confirms the correlation of post neoadjuvant chemotherapy PET SUV with histopathological response, the cut-off of SUV being 5.05 in our cohort. This confirms the predictive value of FDG PET as demonstrated in other studies. Furthermore, its prognostic value with respect to survival has been verified in multiple other studies. With larger scale randomized studies, we may be able to identify the group of patients who have borderline operability anatomically as well as physiologically, where alternative treatment regimens may be indicated to improve outcomes.

4.
JCO Glob Oncol ; 10: e2300292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38301183

RESUMO

PURPOSE: Febrile neutropenia (FN) is a serious complication in hematologic malignancies, and lung infiltrates (LIs) remain a significant concern. An accurate microbiological diagnosis is crucial but difficult to establish. To address this, we analyzed the utility of a standardized method for performing bronchoalveolar lavage (BAL) along with a two-step strategy for the analysis of BAL fluid. PATIENTS AND METHODS: This prospective observational study was conducted at a tertiary cancer center from November 2018 to June 2020. Patients age 15 years and older with confirmed leukemia or lymphomas undergoing chemotherapy, with presence of FN, and LIs observed on imaging were enrolled. RESULTS: Among the 122 enrolled patients, successful BAL was performed in 83.6% of cases. The study used a two-step analysis of BAL fluid, resulting in a diagnostic yield of 74.5%. Furthermore, antimicrobial therapy was modified in 63.9% of patients on the basis of BAL reports, and this population demonstrated a higher response rate (63% v 45%; P = .063). CONCLUSION: Our study demonstrates that a two-step BAL fluid analysis is safe and clinically beneficial to establish an accurate microbiological diagnosis. Given the crucial impact of diagnostic delays on mortality in hematologic malignancy patients with FN, early BAL studies should be performed to enable prompt and specific diagnosis, allowing for appropriate treatment modifications.


Assuntos
Neutropenia Febril , Neoplasias Hematológicas , Leucemia , Linfoma , Adolescente , Humanos , Líquido da Lavagem Broncoalveolar/microbiologia , Neutropenia Febril/diagnóstico , Neutropenia Febril/tratamento farmacológico , Neutropenia Febril/etiologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/microbiologia , Neoplasias Hematológicas/patologia , Leucemia/complicações , Leucemia/patologia , Pulmão/microbiologia , Pulmão/patologia , Linfoma/complicações , Linfoma/diagnóstico , Linfoma/tratamento farmacológico , Estudos Prospectivos
5.
J Biomol Struct Dyn ; 42(2): 1031-1046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37545158

RESUMO

Type 2 Diabetes (T2D), a chronic metabolic disorder characterized by persistent hyperglycemia, accounts for ∼90% of all types of diabetes. Pancreatic α-amylase is a potential drug target for preventing postprandial hyperglycemia and inhibiting T2D in humans. Although many synthetic drugs have been identified against pancreatic α-amylase, however, reported several side effects, and plant-derived natural products are less explored against T2D. This study tested 34 flavonoids derived from the plant Physalis peruviana against the human pancreatic α-amylase (HPA) using in silico computational approaches such as molecular docking and molecular dynamics simulation approaches. Schrödinger, a drug discovery package with modules applicable for molecular docking, protein-ligand interaction analysis, molecular dynamics, post-dynamics simulation, and binding free energy calculation, was employed for all computational studies. Four flavonoids, namely, Chlorogenic acid, Withaperuvin F, Withaperuvin H, and Rutin, were picked based on their docking score ranging between -7.03 kcal/mol and -11.35 kcal/mol compared to the docking score -7.3 kcal/mol of reference ligand, i.e. Myricetin. The molecular dynamics analysis suggested that all flavonoids showed considerable stability within the protein's catalytic pocket, except chlorogenic acid, which showed high deviation during the last 15 ns. However, the interactions observed in initial docking and extracted from the simulation trajectory involved > 90% identical residues, indicating the affinity and stability of the docked flavonoids with the protein. Therefore, all four compounds identified in this study are proposed as promising antidiabetic candidates and should be further considered for their in vitro and in vivo validation.Communicated by Ramaswamy H. Sarma.


Assuntos
Diabetes Mellitus Tipo 2 , Physalis , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases , Ácido Clorogênico , Ligantes , Simulação de Acoplamento Molecular , alfa-Amilases Pancreáticas , Flavonoides , Simulação de Dinâmica Molecular
6.
Environ Sci Pollut Res Int ; 30(59): 123181-123192, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979103

RESUMO

In vertebrates, insulin-like growth like factors (IGFs) play an important role in growth and other physiological processes. The GH-IGF axis is considered a valuable tool to monitor fish growth performance. Herein, we report the molecular characterization of igf-1, igf-2, and ß-actin transcripts and relative expression of igf-1 and igf-2 in the liver and muscle tissue of cage-reared butter catfish, Ompok bimaculatus, in response to different stocking densities (T1, 15 fingerlings m-3; T2, 25 fingerlings m-3; and T3, 35 fingerlings m-3) over 180 days of culture duration. The length of the partial amplified transcript sequence of Obigf-1, Obigf-2, and Obß-actin was 325, 438, and 924 bp, respectively. Phylogenetically, Obigf-1 and Obigf-2 were closely clustered with catfishes, viz., Clarias magur, Bagarius yarrelli, and Silurus asotus. The expression of igf-1 was significantly downregulated in the liver at higher densities after 120 days as biomass in the cages increased, while igf-2 expression did not change with the stocking densities over the culture period. Cortisol concentration was significantly elevated in T3 groups post 150 days of the culture period and correlated negatively with the expression of igf-1 (p < 0.05) and igf-2 (p > 0.05). Environmental parameters, pH, TDS, hardness, conductivity, and alkalinity showed a significant positive correlation with hepatic IGF expression. Our study indicates that the liver-derived igf-1 plays a more important role in the regulation of growth in response to culture density in the species studied, and thus, igf-1 can be used effectively as a biomarker for growth. Furthermore, this study will help in planning a proper harvest schedule and optimize the culture practices of O. bimaculatus in an open water cage system.


Assuntos
Peixes-Gato , Fator de Crescimento Insulin-Like II , Fator de Crescimento Insulin-Like I , Animais , Peixes-Gato/genética , Ecossistema , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/genética , Peptídeos Semelhantes à Insulina
7.
bioRxiv ; 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37645800

RESUMO

Enzymes populate ensembles of structures with intrinsically different catalytic proficiencies that are difficult to experimentally characterize. We use time-resolved mix-and-inject serial crystallography (MISC) at an X-ray free electron laser (XFEL) to observe catalysis in a designed mutant (G150T) isocyanide hydratase (ICH) enzyme that enhances sampling of important minor conformations. The active site exists in a mixture of conformations and formation of the thioimidate catalytic intermediate selects for catalytically competent substates. A prior proposal for active site cysteine charge-coupled conformational changes in ICH is validated by determining structures of the enzyme over a range of pH values. A combination of large molecular dynamics simulations of the enzyme in crystallo and time-resolved electron density maps shows that ionization of the general acid Asp17 during catalysis causes additional conformational changes that propagate across the dimer interface, connecting the two active sites. These ionization-linked changes in the ICH conformational ensemble permit water to enter the active site in a location that is poised for intermediate hydrolysis. ICH exhibits a tight coupling between ionization of active site residues and catalysis-activated protein motions, exemplifying a mechanism of electrostatic control of enzyme dynamics.

8.
Nanoscale ; 15(30): 12748-12770, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37477348

RESUMO

Aggregation of both amyloid beta (Aß) peptide and hyperphosphorylated tau proteins is the major pathological hallmark of Alzheimer's disease (AD). Moieties that carry anti-amyloidogenic potency against both of the aggregating entities are considered to be promising drug candidatures for the disease. In the current work, we have synthesized amphipathic dipeptide vesicle-templated selenium nanoparticles (RΔF-SeNPs) as potential entities to combat AD. We have investigated and established their anti-amyloidogenic activity against different peptide-based amyloid models, such as the reductionist model based on the dipeptide phenylalanine-phenylalanine (FF) derived from Aß; a model based on the hexapeptide Ac-PHF6 (306VQIVYK311) derived from tau protein; and the full-length Aß42 polypeptide-based model. We also evaluated the neuroprotective characteristics of RΔF-SeNPs against FF, Ac-PHF6, and Aß42 fibril-induced toxicity in neuroblastoma, SH-SY5Y cells. RΔF-SeNPs further exhibited neuroprotective effects in streptozotocin (STZ) treated neuronal (N2a) cells carrying AD-like features. In addition, studies conducted in an intra-cerebroventricular STZ-instigated rat model of dementia revealed that RΔF-SeNP-treated animals showed improved cognitive activity and reduced Aß42 aggregate burden in brain tissues as compared with the STZ-treated group. Moreover, in vivo brain distribution studies conducted in animal models additionally demonstrated the brain-homing ability of RΔF-SeNPs. All together, these studies supported the potency of RΔF-SeNPs as efficient and propitious disease-modifying therapeutic agents for combating AD.


Assuntos
Doença de Alzheimer , Nanopartículas , Neuroblastoma , Selênio , Ratos , Humanos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Selênio/farmacologia , Arginina , Fenilalanina/farmacologia , Dipeptídeos , Estreptozocina/uso terapêutico , Nanopartículas/uso terapêutico , Fragmentos de Peptídeos/farmacologia
9.
Curr Alzheimer Res ; 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37282567

RESUMO

AIMS: Caffeine possesses potent antioxidant, anti-inflammatory and anti-apoptotic activities against a variety of neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). The goal of this study was to investigate the protective role of a psychoactive substance like caffeine on hippocampal neurogenesis and memory functions in streptozotocin (STZ)-induced neurodegeneration in rats. BACKGROUND: Caffeine is a natural CNS stimulant, belonging to the methylxanthine class, and is a widely consumed psychoactive substance. It is reported to abate the risk of various abnormalities that are cardiovascular system (CVS) related, cancer related, or due to metabolism dysregulation. Short-term caffeine exposure has been widely evaluated, but its chronic exposure is less explored and pursued. Several studies suggest a devastating role of caffeine in neurodegenerative disorders. However, the protective role of caffeine on neurodegeneration is still unclear. OBJECTIVE: Here, we examined the effects of chronic caffeine administration on hippocampal neurogenesis in intracerebroventricular STZ injection induced memory dysfunction in rats. The chronic effect of caffeine on proliferation and neuronal fate determination of hippocampal neurons was evaluated by co-labeling of neurons by thymidine analogue BrdU that labels new born cells, DCX (a marker for immature neurons) and NeuN that labels mature neurons. METHOD: STZ (1 mg/kg, 2 µl) was injected stereotaxically into the lateral ventricles (intracerebroventricular injection) once on day 1, followed by chronic treatment with caffeine (10 mg/kg, i.p) and donepezil (5 mg/kg, i.p.). Protective effect of caffeine on cognitive impairment and adult hippocampal neurogenesis was evaluated. RESULT: Our findings show decreased oxidative stress burden and amyloid burden following caffeine administration in STZ lesioned SD rats. Further, double immunolabeling with bromodeoxyuridine+/doublecortin+ (BrdU+/DCX+) and bromodeoxyuridine+/ neuronal nuclei+ (BrdU+/NeuN+) has indicated that caffeine improved neuronal stem cell proliferation and long term survival in STZ lesioned rats. CONCLUSION: Our findings support the neurogenic potential of caffeine in STZ induced neurodegeneration.

10.
ACS Chem Neurosci ; 14(12): 2271-2281, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37261380

RESUMO

The functional and developmental unit of neurogenesis is neural stem cells (NSCs). These NSCs have self-renewal capacity and produce new neurons throughout life in different neurogenic niche. Neurogenesis in adult brain is associated with synaptic plasticity, learning, and memory in dentate gyrus (DG) of hippocampus and olfactory bulb. Remarkably, weakened neurogenesis has been viewed before the onset of different pathological hallmarks of neurological disorders. In this review, we have provided evidence which implicates impaired neurogenesis as a culprit in age associated neurological disorders with greater emphasis on Alzheimer's disease (AD). Moreover, an insight about the molecular and cellular regulation linked with altered neurogenesis in young and aging brain has also been discussed. This review further summarizes the therapeutic strategies for targeting the manipulation of the neural stem cell pool and factors affecting the pool involved in AD.


Assuntos
Doença de Alzheimer , Células-Tronco Neurais , Adulto , Humanos , Doença de Alzheimer/patologia , Hipocampo/patologia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Neurônios/patologia
11.
Eur J Pharmacol ; 946: 175623, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36871666

RESUMO

Activation of the renin-angiotensin system (RAS), by Angiotensin converting enzyme/Angiotensin II/Angiotensin receptor-1 (ACE/Ang II/AT1 R) axis elicits amyloid deposition and cognitive impairment. Furthermore, ACE2 induced release of Ang-(1-7) binds with the Mas receptor and autoinhibits ACE/Ang II/AT1 axis activation. Inhibition of ACE by perindopril has been reported to improve memory in preclinical settings. However, the functional significance and mechanism by which ACE2/Mas receptor regulate cognitive functions and amyloid pathology is not known. The present study is aimed to determine the role of ACE2/Ang-(1-7)/Mas receptor axis in STZ induced rat model of Alzheimer's disease (AD). We have used pharmacological, biochemical and behavioural approaches to identify the role of ACE2/Ang-(1-7)/Mas receptor axis activation on AD-like pathology in both in vitro and invivo models. STZ treatment enhances ROS formation, inflammation markers and NFκB/p65 levels which are associated with reduced ACE2/Mas receptor levels, acetylcholine activity and mitochondrial membrane potential in N2A cells. DIZE mediated ACE2/Ang-(1-7)/Mas receptor axis activation resulted in reduced ROS generation, astrogliosis, NFκB level and inflammatory molecules and improved mitochondrial functions along with Ca2+ influx in STZ treated N2A cells. Interestingly, DIZE induced activation of ACE2/Mas receptor significantly restored acetylcholine levels and reduced amyloid-beta and phospho-tau deposition in cortex and hippocampus that resulted in improved cognitive function in STZ induced rat model of AD-like phenotypes. Our data indicate that ACE2/Mas receptor activation is sufficient to prevented cognitive impairment and progression of amyloid pathology in STZ induced rat model of AD-like phenotypes. These findings suggest the potential role of ACE2/Ang-(1-7)/Mas axis in AD pathophysiology by regulating inflammation cognitive functions.


Assuntos
Doença de Alzheimer , Ratos , Animais , Doença de Alzheimer/patologia , Estreptozocina , Enzima de Conversão de Angiotensina 2/genética , Espécies Reativas de Oxigênio , Acetilcolina , Peptidil Dipeptidase A/metabolismo , Cognição , Inflamação/tratamento farmacológico , Fenótipo , Fragmentos de Peptídeos/farmacologia , Angiotensina I/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Angiotensina II/farmacologia
12.
Front Genet ; 14: 1057068, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845373

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder and considered to be responsible for majority of worldwide prevalent dementia cases. The number of patients suffering from dementia are estimated to increase up to 115.4 million cases worldwide in 2050. Hence, AD is contemplated to be one of the major healthcare challenge in current era. This disorder is characterized by impairment in various signaling molecules at cellular and nuclear level including aggregation of Aß protein, tau hyper phosphorylation altered lipid metabolism, metabolites dysregulation, protein intensity alteration etc. Being heterogeneous and multifactorial in nature, the disease do not has any cure or any confirmed diagnosis before the onset of clinical manifestations. Hence, there is a requisite for early diagnosis of AD in order to downturn the progression/risk of the disorder and utilization of newer technologies developed in this field are aimed to provide an extraordinary assistance towards the same. The lipidomics and proteomics constitute large scale study of cellular lipids and proteomes in biological matrices at normal stage or any stage of a disease. The study involves high throughput quantification and detection techniques such as mass spectrometry, liquid chromatography, nuclear mass resonance spectroscopy, fluorescence spectroscopy etc. The early detection of altered levels of lipids and proteins in blood or any other biological matrices could aid in preventing the progression of AD and dementia. Therefore, the present review is designed to focus on the recent techniques and early diagnostic criteria for AD, revealing the role of lipids and proteins in this disease and their assessment through different techniques.

13.
Mol Neurobiol ; 60(1): 203-227, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36251234

RESUMO

Neuroinflammation is associated with activation of glial cells and pro-inflammatory arm of the central Renin Angiotensin System (RAS) namely, Angiotensin-Converting Enzyme/Angiotensin II/Angiotensin Type 1 Receptor (ACE/Ang II/AT1R) axis. Apart from this, another axis of RAS also exists, Angiotensin-Converting Enzyme 2/Angiotensin (1-7)/Mas Receptor (ACE2/Ang (1-7)/MasR), which counters ACE/Ang II/AT1R axis by showing anti-inflammatory properties. However, the role of ACE2/Ang (1-7)/MasR axis has not been explored in glial activation and neuroinflammation. Hence, the present study tries to unveil the role of ACE2/Ang (1-7)/MasR axis in lipopolysaccharide (LPS)-induced neuroinflammation using diminazene aceturate (DIZE), an ACE2 activator, in astroglial (C6) and microglial (BV2) cells as well as male SD rats. We found that ACE2 activation efficiently prevented LPS-induced changes by decreasing glial activation, inflammatory signaling, cell migration, ROS generation via upregulation of ACE2/Ang (1-7)/MasR signaling. In addition, activation of ACE2/Ang (1-7)/MasR axis by DIZE significantly suppressed the pro-inflammatory ACE/Ang II/AT1R axis by reducing Ang II level in neuroinflammatory conditions induced by LPS in both in vitro and in vivo. ACE2/Ang (1-7)/MasR axis activation further decreased mitochondrial depolarization and apoptosis, hence providing neuroprotection. Furthermore, to validate that the beneficial effect of the ACE2 activator was indeed through MasR, a selective MasR antagonist (A779) was used that significantly blocked the anti-inflammatory effect of ACE2 activation by DIZE. Hence, our study demonstrated that ACE2 activation imparted neuroprotection by enhancing ACE2/Ang (1-7)/MasR signaling which in turn decreased glial activation, neuroinflammation, and apoptosis and improved mitochondrial health.


Assuntos
Enzima de Conversão de Angiotensina 2 , Neuroglia , Animais , Masculino , Ratos , Angiotensina I/farmacologia , Angiotensina II/farmacologia , Anti-Inflamatórios , Lipopolissacarídeos/farmacologia , Doenças Neuroinflamatórias , Fragmentos de Peptídeos/farmacologia , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina , Receptores Acoplados a Proteínas G , Neuroglia/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-36219397

RESUMO

The standard of care for esophageal malignancies has evolved over the years from open transthoracic esophagectomy to a minimally invasive approach due to the reduction in surgical trauma and significant impact on postoperative outcomes. Minimally invasive approaches include video-assisted thoracoscopic surgery and robot-assisted thoracoscopic surgery. These minimally invasive approaches have an attendant learning curve that early-career surgeons are required to negotiate before achieving proficiency in the procedure. Recurrent laryngeal nerve injury is a particularly significant problem, especially in the presence of enlarged supracarinal lymph nodes, which mandate a 3-field lymphadenectomy. With technological advances and the use of intraoperative nerve monitoring, iatrogenic nerve injury can at best be avoided or at least be recognized, and corrective measures can be undertaken to reduce postoperative morbidity. In this video tutorial, we demonstrate a standard robot-assisted esophagectomy and a 3-field lymphadenectomy with the use of intraoperative nerve monitoring followed by an esophagogastric anastomosis with the triangulating stapling technique.


Assuntos
Neoplasias Esofágicas , Procedimentos Cirúrgicos Robóticos , Robótica , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Humanos , Excisão de Linfonodo/métodos , Procedimentos Cirúrgicos Robóticos/métodos
15.
Chem Rev ; 122(16): 13800-13880, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35904776

RESUMO

Reaction discovery and catalyst screening lie at the heart of synthetic organic chemistry. While there are efforts at de novo catalyst design using computation/artificial intelligence, at its core, synthetic chemistry is an experimental science. This review overviews biomacromolecule-assisted screening methods and the follow-on elaboration of chemistry so discovered. All three types of biomacromolecules discussed─enzymes, antibodies, and nucleic acids─have been used as "sensors" to provide a readout on product chirality exploiting their native chirality. Enzymatic sensing methods yield both UV-spectrophotometric and visible, colorimetric readouts. Antibody sensors provide direct fluorescent readout upon analyte binding in some cases or provide for cat-ELISA (Enzyme-Linked ImmunoSorbent Assay)-type readouts. DNA biomacromolecule-assisted screening allows for templation to facilitate reaction discovery, driving bimolecular reactions into a pseudo-unimolecular format. In addition, the ability to use DNA-encoded libraries permits the barcoding of reactants. All three types of biomacromolecule-based screens afford high sensitivity and selectivity. Among the chemical transformations discovered by enzymatic screening methods are the first Ni(0)-mediated asymmetric allylic amination and a new thiocyanopalladation/carbocyclization transformation in which both C-SCN and C-C bonds are fashioned sequentially. Cat-ELISA screening has identified new classes of sydnone-alkyne cycloadditions, and DNA-encoded screening has been exploited to uncover interesting oxidative Pd-mediated amido-alkyne/alkene coupling reactions.


Assuntos
Alcinos , Inteligência Artificial , Alcinos/química , Aminação , Catálise , DNA
16.
ACS Chem Neurosci ; 13(10): 1491-1504, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35533351

RESUMO

Hypertension is reported to cause major brain disorders including Parkinson's disease (PD), apart from cardiovascular and chronic kidney disorders. Considering this, for the first time, we explored the effect of modulation of the ACE2/Ang (1-7)/MasR axis using diminazene aceturate (DIZE), an ACE2 activator, in 6-hydroxydopamine (6-OHDA) induced PD model. We found that DIZE treatment improved neuromuscular coordination and locomotor deficits in the 6-OHDA induced PD rat model. Further, the DIZE-mediated activation of ACE2 led to increased tyrosine hydroxylase (TH) and dopamine transporters (DAT) expression in the rat brain, indicating the protection of dopaminergic (DAergic) neurons from 6-OHDA induced neurotoxicity. Moreover, 6-OHDA induced activation of glial cells (astrocytes and microglia) and release of neuroinflammatory mediators were attenuated by DIZE treatment in both in vitro as well as in vivo models of PD. DIZE exerted its effect by activating ACE2 that produced Ang (1-7), a neuroprotective peptide. Ang (1-7) conferred its neuroprotective effect upon binding with the G-protein-coupled MAS receptor that led to the upregulation of cell survival proteins while downregulating apoptotic proteins. Importantly, these findings were further validated by using A-779, a MasR antagonist. The result showed that treatment with A-779 reversed the antioxidative and anti-inflammatory effects of DIZE by decreasing glial activation and neuroinflammatory markers. Although the role of ACE2 in PD pathology needs to be additionally confirmed using transgenic models in either ACE2 overexpressing or knockout mice, still, our study demonstrates that enhancing ACE2 activity could be a novel approach for ameliorating PD pathology.


Assuntos
Enzima de Conversão de Angiotensina 2 , Diminazena/análogos & derivados , Doença de Parkinson , Angiotensina I/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Diminazena/farmacologia , Camundongos , Modelos Teóricos , Oxidopamina/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/enzimologia , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Proto-Oncogene Mas/metabolismo , Ratos , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
ACS Appl Mater Interfaces ; 14(11): 13079-13093, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35263093

RESUMO

Aggregation of ß-amyloid (Aß42) peptide in the neural extracellular space leads to cellular dysfunction, resulting in Alzheimer's disease (AD). The hydrophobic core of the amyloidogenic Aß42 peptide contains aromatic residues that play an important role in the self-assembly and subsequent aggregation of the peptide. Hence, targeting these hydrophobic core residues by potent low molecular agents can be a promising therapeutic approach toward AD. In the current work, we have developed self-fluorescent solo tryptophan nanoparticles (TNPs) as nanotheranostic systems against AD. We demonstrated that TNPs could significantly inhibit as well as disrupt the fibrils formed by both Aß42 peptide and another reductionist approach-based amyloid model dipeptide, phenylalanine-phenylalanine (FF). More importantly, these nanostructures were nontoxic to neural cells and could protect the neurons from Aß42 peptide and FF aggregate-induced cytotoxicity. In addition, efficacy studies performed in animal model further revealed that the TNPs could rescue spatial and learning memory in intracerebroventricular streptozotocin-administration-induced AD phenotype in rats. Moreover, our pharmacokinetics study further established the BBB permeability and brain delivery potency of TNPs. The inherent excellent fluorescent properties of these nanoparticles could be exploited further to use them as imaging modalities for tagging and detecting FF and Aß42 peptide fibrils. Overall, our results clearly illustrated that the solo TNPs could serve as promising nanotheranostic agents for AD therapy.


Assuntos
Doença de Alzheimer , Nanopartículas , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/química , Animais , Nanopartículas/uso terapêutico , Fragmentos de Peptídeos/química , Ratos , Nanomedicina Teranóstica , Triptofano/farmacologia
18.
Life Sci ; 286: 119989, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597609

RESUMO

AIMS: Isoformononetin (IFN), a methoxyl isoflavone present in most of human dietary supplements. However, being a highly potent antioxidant and anti-inflammatory molecule, its activity against neuronal oxidative stress and neuroinflammation has not been explored till now. The present study was inquested to assess the antioxidant, anti-apoptotic and anti-inflammatory activity of IFN against streptozotocin induced neuroinflammation in different brain regions of rat. MAIN METHODS: Four groups of animals were subjected to treatment as control, toxic control (STZ; single intracerebrovascular injection), third group (STZ + IFN; 20 mg/kg p.o.), fourth group (IFN) for 14 days. The different brain regions of rats were evaluated for inflammatory, apoptotic and biochemical antioxidant markers. The brain tissues were further assessed for gene expression, immunohistochemical and western blotting examination for localization of inflammasome cascade expression that plays a pivotal role in neuroinflammation. KEY FINDINGS: The modulation in oxidant/antioxidant status after exposure of STZ was significantly balanced after administration of IFN to rats. Further, IFN was also found to be an apoptotic agent as it modulates the apoptotic gene (Bax) and anti-apoptotic gene (BcL2) expression. IFN significantly curtailed the augmented protein expression of NLRP3, NLRP2, ASC, NFκBP65, IL-1ß and caspase-1 due to STZ administration in cortex and hippocampus rat brain regions. SIGNIFICANCE: The aforementioned results proclaim the neuroprotective functioning of IFN against STZ induced inflammation. IFN significantly prevents the neuroinflammation by decreasing the generation of ROS that reduces the activation of NLRP3/ASC/IL-1 axis thereby exerting neuroprotection as evidenced in rat model of STZ induced neuroninflammation.


Assuntos
Antioxidantes/farmacologia , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Encefalite/prevenção & controle , Interleucina-1/metabolismo , Isoflavonas/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estreptozocina/toxicidade , Animais , Modelos Animais de Doenças , Encefalite/induzido quimicamente , Encefalite/metabolismo , Encefalite/patologia , Expressão Gênica/fisiologia , Interferons/fisiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Óxido Nítrico/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Coelhos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-34672142

RESUMO

Mediastinal staging in potentially resectable non-small cell lung cancer is of paramount importance since it impacts the survival of the patient. With increasing nodal stage, survival was noted to precipitously decline. Nodal status also determined the use of neoadjuvant/adjuvant therapy and other treatment modalities. Various methods of obtaining lymphatic tissue from the mediastinum for staging purposes have been described in the literature, although mediastinoscopic lymph node evaluation remains the gold standard. Endoscopic methods of mediastinal staging, like the endobronchial ultrasound guided and esophageal ultrasound guided fine-needle aspiration techniques, although minimally invasive, provide the highest levels of accuracy when used in conjunction with surgical mediastinal staging. Video-assisted mediastinoscopic lymphadenectomy (VAMLA) provides clear advantages, as far as ergonomics and training are concerned, over conventional mediastinoscopy. Access to stations 2R, 2L, 4R, 4L, and 7 is feasible with VAMLA. In this video vignette, we present the step-by-step technique of a standard VAMLA, with an overview of relevant anatomical relationships, for the effective and safe clearance of lymph node stations for the purposes of staging and defining appropriate therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Mediastinoscopia , Mediastino/patologia , Mediastino/cirurgia , Estadiamento de Neoplasias
20.
Artigo em Inglês | MEDLINE | ID: mdl-34705352

RESUMO

This video tutorial describes a left lower lobectomy performed by the uniportal approach. A single 2-cm incision in the lateral chest wall is used as the utility port. The procedure begins with division of the inferior pulmonary ligament and isolation of the inferior pulmonary vein. This patient has densely adherent interlobar nodes, which are then dissected to demonstrate the interlobar pulmonary artery. Then we proceed to divide the anterior part of the fissure after identifying and safeguarding the lingular branches of the pulmonary artery. This step is followed by the division of the posterior part of the fissure after identification of the posterior branches of the pulmonary artery to the upper lobe. Then we identify the basilar trunk and divide it using endostaplers. Other branches of the interlobar artery are clearly identified, and the apicobasal artery is taken separately. This is followed by division of the inferior pulmonary vein and a systematic mediastinal nodal dissection.


Assuntos
Neoplasias Pulmonares , Cirurgia Torácica Vídeoassistida , Humanos , Pulmão , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Artéria Pulmonar/cirurgia
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