Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Chemistry ; 30(6): e202302679, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-37966848

RESUMO

Establishment of a scaling relation among the reaction intermediates is highly important but very much challenging on complex surfaces, such as surfaces of high entropy alloys (HEAs). Herein, we designed an interpretable machine learning (ML) approach to establish a scaling relation among CO2 reduction reaction (CO2 RR) intermediates adsorbed at the same adsorption site. Local Interpretable Model-Agnostic Explanations (LIME), Accumulated Local Effects (ALE), and Permutation Feature Importance (PFI) are used for the global and local interpretation of the utilized black box models. These methods were successfully applied through an iterative way and validated on CuCoNiZnMg and CuCoNiZnSnbased HEAs data. Finally, we successfully predicted adsorption energies of *H2 CO (MAE: 0.24 eV) and *H3 CO (MAE: 0.23 eV) by using the *HCO training data. Similarly, adsorption energy of *O (MAE: 0.32 eV) is also predicted from *H training data. We believe that our proposed method can shift the paradigm of state-of-the-art ML in catalysis towards better interpretability.

2.
Inorg Chem ; 63(40): 18727-18737, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39321419

RESUMO

Atomically precise copper nanoclusters (NCs) attract research interest due to their intense photoluminescence, which enables their applications in photonics, optoelectronics, and sensing. Exploring these properties requires carefully designed clusters with atomic precision and a detailed understanding of their atom-specific luminescence properties. Here, we report two copper NCs, [Cu4(MNA)2(DPPE)2] and [Cu6(MNA-H)6], shortly Cu4 and Cu6, protected by 2-mercaptonicotinic acid (MNA-H2) and 1,2-bis(diphenylphosphino)ethane (DPPE), showing "turn-off" mechanoresponsive luminescence. Single-crystal X-ray diffraction reveals that in the Cu4 cluster, two Cu2 units are appended with two thiols, forming a flattened boat-shaped Cu4S2 kernel, while in the Cu6 cluster, two Cu3 units form an adamantane-like Cu6S6 kernel. High-resolution electrospray ionization mass spectrometry studies reveal the molecular nature of these clusters. Lifetime decay profiles of the two clusters show the average lifetimes of 0.84 and 1.64 µs, respectively. These thermally stable Cu NCs become nonluminescent upon mechanical milling but regain their emission upon exposure to solvent vapors. Spectroscopic data of the clusters match well with their computed electronic structures. This work expands the collection of thermally stable and mechanoresponsive luminescent coinage metal NCs, enriching the diversity and applications of such materials.

3.
Inorg Chem ; 62(21): 8080-8092, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37196200

RESUMO

Diruthenium complexes [{(η6-arene)RuCl}2(µ-κ2:κ2-benztetraimd)]2+ containing the bridging bis-imidazole methane-based ligand {1,4-bis(bis(2-ethyl-5-methyl-1H-imidazol-4-yl)methyl)benzene} (benztetraimd) are synthesized for catalytic formic acid dehydrogenation in water at 90 °C. Catalyst [{(η6-p-cymene)RuCl}2(µ-κ2:κ2-benztetraimd)]2+ [1-Cl2] exhibited a remarkably high turnover frequency (1993 h-1 per Ru atom) and long-term stability over 60 days for formic acid dehydrogenation, while the analogous (η6-benzene)diruthenium and mononuclear catalysts displayed low activity with poor long-term stability. Notably, catalyst [1-Cl2] also displayed an appreciably high turnover number of 93 200 for the bulk-scale reaction. In addition, the in-depth mass and nuclear magnetic resonance investigations under the catalytic and control experimental conditions revealed the active involvement of several crucial catalytic intermediate species, such as Ru-aqua species [{(η6-p-cymene)Ru(H2O)}2(µ-L)]2+ [1-(OH2)2], Ru-formato species [{(η6-p-cymene)Ru(HCOO)}2(µ-L)] [1-(HCOO)2], and Ru-hydrido species [{(η6-p-cymene)Ru(H)}2(µ-L)] [1-(H)2], in the catalytic formic acid dehydrogenation reaction.

4.
Phys Chem Chem Phys ; 24(14): 8387-8397, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35332910

RESUMO

The conversion of CO2 to DMM is an important transformation for various reasons. Co and Ru-based triphos catalysts have been investigated using density functional theory (DFT) calculations to understand the mechanistic pathways of the CO2 to DMM conversion and the role of noble/non-noble metal-based catalysts. The reaction has been investigated sequentially through methylformate (MF) and methoxymethane (MM) intermediates as they are found to be important intermediates. For the hydrogenation of CO2 and MF, the hydrogen sources such as H2 and methanol have been investigated. The calculated reaction free energy barriers for all the possible pathways suggest that both hydrogen sources are important for the Co-triphos catalyst. However, in the case of the Ru-triphos catalyst, molecular H2 is calculated to be the only hydrogen source. Various esterification and acetalization possibilities have also been explored to find the most favorable pathway for the conversion of CO2 to DMM. We find that the hydride transfer to the CO2 is the rate determining step (RDS) for the overall reaction. Our mechanistic investigation reveals that the metal center is the active part for the catalysis rather than the Brønsted acid and the redox triphos ligand plays an important role through the push-pull mechanism. The implemented microkinetic study shows that the reaction is also quite dependent on the concentration of the gaseous reactants and the rate constant increases exponentially above 363 K.

5.
Support Care Cancer ; 24(2): 585-595, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26111955

RESUMO

PURPOSE: This study investigated the effectiveness of a structured telephone intervention for caregivers of people diagnosed with poor prognosis gastrointestinal cancer to improve psychosocial outcomes for both caregivers and patients. METHODS: Caregivers of patients starting treatment for upper gastrointestinal or Dukes D colorectal cancer were randomly assigned (1:1) to the Family Connect telephone intervention or usual care. Caregivers in the intervention group received four standardized telephone calls in the 10 weeks following patient hospital discharge. Caregivers' quality of life (QOL), caregiver burden, unmet supportive care needs and distress were assessed at 3 and 6 months. Patients' QOL, unmet supportive care needs, distress and health service utilization were also assessed at these time points. RESULTS: Caregivers (128) were randomized to intervention or usual care groups. At 3 months, caregiver QOL scores and other caregiver-reported outcomes were similar in both groups. Intervention group participants experienced a greater sense of social support (p = .049) and reduced worry about finances (p = .014). Patients whose caregiver was randomized to the intervention also had fewer emergency department presentations and unplanned hospital readmissions at 3 months post-discharge (total 17 vs. 5, p = .01). CONCLUSIONS: This standardized intervention did not demonstrate any significant improvements in caregiver well-being but did result in a decrease in patient emergency department presentations and unplanned hospital readmissions in the immediate post-discharge period. The trend towards improvements in a number of caregiver outcomes and the improvement in health service utilization support further development of telephone-based caregiver-focused supportive care interventions.


Assuntos
Adaptação Psicológica , Cuidadores/psicologia , Neoplasias Gastrointestinais/mortalidade , Qualidade de Vida/psicologia , Apoio Social , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Prognóstico , Telefone
6.
Childs Nerv Syst ; 31(8): 1341-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25874845

RESUMO

PURPOSE: The aim of this study was to review cases of paediatric patients with craniovertebral junction (CVJ) tuberculosis with a view to try and stratify the cases into different groups which would help plan treatment and hence develop a protocol for treatment of a fairly uncommon condition still widely seen in the developing world. METHODS: Twenty-three cases of paediatric craniovertebral tuberculosis had their clinical features and radiology reviewed. The treatment plan in each case was analyzed according to their presentation. The results of treatment after 1 year were assessed in each case. RESULTS: The clinical presentations varied from neck pain with hypoglossal nerve palsy to frank spastic quadriparesis, and frank instability at the atlanto-axial junction was seen in five out of 23 patients. Cold abscesses were seen in 18/23 cases, and severe torticollis was the presentation in 6/23. We graded the children with this condition into three groups: 1) those with instability and gross neurodeficit who required early operative intervention (1 needed trans-oral decompression with posterior fixation and 4 required posterior fixation) 2) those who had severe torticollis and large cold abscesses who were treated with trans-oral aspiration of cold abscess followed by neck immobilization (6/23) and 3) those who did not have significant neck muscle spasm or torticollis and who were treated with immobilization alone (12/23). Only one child in group 3 required delayed intervention for instability which developed after completion of the course of anti-tubercular medication. CONCLUSIONS: We concluded that children with craniovertebral tuberculosis should be treated according to their clinical presentation coupled with evidence of radiological instability. Those with gross deficit and instability need early stabilization, those with minimal deficit and no instability but severe pain or torticollis need aspiration of the cold abscess with external immobilization, whereas those without deficit, instability or severe pain may be managed by external orthoses alone. Of course, medical treatment for tuberculosis is necessary in each case.


Assuntos
Articulação Atlantoaxial/patologia , Articulação Atlantoccipital/patologia , Tuberculose/classificação , Tuberculose/cirurgia , Adolescente , Criança , Pré-Escolar , Avaliação da Deficiência , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tuberculose/diagnóstico
7.
Eur Spine J ; 24 Suppl 4: S606-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25662907

RESUMO

PURPOSE: Hemangiopericytoma is a rare tumor of CNS with potential for recurrence and widespread metastasis, even outside CNS with even rare involvement of spinal cord. This case series presents five patients to evaluate the clinical presentation, radiological features, management, pathology and outcome of spinal hemangiopericytomas. METHODS: Between 2004 and 2013, five patients underwent surgery for spinal hemangiopericytoma. Histopathological data were reviewed in all cases and clinical and follow-up details were collected from the data available in our department. RESULTS: There were three males and two females, including one pediatric patient. Three patients had dorsal spine involvement and two patients had involvement of cervical spine. There were two patients with intradural extramedullary tumors, one patient each with pure intramedullary tumor, pure extradural tumor and both intra and extradural tumor. All of them presented with motor weakness. Gross total resection of the tumor was done in three patients. Four patients received post-operative radiotherapy. Histopathology showed anaplastic tumor in four cases with high MIB-1 LI. Most of them were positive for CD34, mic-2 and bcl-2. Three patients who underwent gross total resection improved significantly in the follow-up period. Two patients who underwent subtotal resection expired due to spread of their disease. CONCLUSION: Spinal hemangiopericytoma is a rare tumor. Strong clinical suspicion is required to diagnose it pre-operatively. Gross total resection is the goal and radiotherapy should be given in case of residual tumor or high-grade tumors.


Assuntos
Hemangiopericitoma/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Adulto , Vértebras Cervicais , Criança , Feminino , Hemangiopericitoma/patologia , Hemangiopericitoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/patologia , Neoplasias da Coluna Vertebral/cirurgia
8.
Nanoscale ; 16(4): 1758-1769, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38167690

RESUMO

The design of efficient electrocatalysts for improving hydrogen evolution reaction (HER) performance using atomically precise metal nanoclusters (NCs) is an emerging area of research. Here, we have studied the HER electrocatalytic performance of monometallic Cu6 and Au6 nanoclusters and bimetallic Au4Cu2 nanoclusters. A bimetallic Au4Cu2/MoS2 composite exhibits excellent HER catalytic activity with an overpotential (η10) of 155 mV vs. reversible hydrogen electrode observed at 10 mA cm-2 current density. The improved HER performance in Au4Cu2 is due to the increased electrochemically active surface area (ECSA), and Au4Cu2 NCs exhibits better stability than Cu6 and Au6 systems and bare MoS2. This augmentation offers a greater number of active sites for the favorable adsorption of reaction intermediates. Furthermore, by employing X-ray photoelectron spectroscopy (XPS) and Raman analysis, the kinetics of HER in the Au4Cu2/MoS2 composite were elucidated, attributing the favorable performance to better electronic interactions occurring at the interface between Au4Cu2 NCs and the MoS2 substrate. Theoretical analysis reveals that the inherent catalytic enhancement in Au4Cu2/MoS2 is due to favorable H atom adsorption over it and the smallest ΔGH* value. The downshift in the d-band of the Au4Cu2/MoS2 composite influences the binding energy of intermediate catalytic species. This new catalyst sheds light on the structure-property relationship for improving electrocatalytic performance at the atomic level.

9.
Chem Sci ; 15(34): 13741-13752, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39211504

RESUMO

Copper nanoclusters exhibit unique structural features and their molecular assembly results in diverse photoluminescence properties. In this study, we present ligand-dependent multicolor luminescence observed in a Cu14 cluster, primarily protected by ortho-carborane-9,12-dithiol (o-CBDT), featuring an octahedral Cu6 inner kernel enveloped by eight isolated copper atoms. The outer layer of the metal kernel consists of six bidentate o-CBDT ligands, in which carborane backbones are connected through µ3-sulphide linkages. The initially prepared Cu14 cluster, solely protected by six o-CBDT ligands, did not crystallize in its native form. However, in the presence of N,N-dimethylformamide (DMF), the cluster crystallized along with six DMF molecules. Single-crystal X-ray diffraction (SCXRD) revealed that the DMF molecules were directly coordinated to six of the eight capping Cu atoms, while oxygen atoms were bound to the two remaining Cu apices in antipodal positions. Efficient tailoring of the cluster surface with DMF shifted its luminescence from yellow to bright red. Luminescence decay profiles showed fluorescence emission for these clusters, originating from the singlet states. Additionally, we synthesized microcrystalline fibers with a one-dimensional assembly of DMF-appended Cu14 clusters and bidentate DPPE linkers. These fibers exhibited bright greenish-yellow phosphorescence emission, originating from the triplet state, indicating the drastic surface tailoring effect of secondary ligands. Theoretical calculations provided insights into the electronic energy levels and associated electronic transitions for these clusters. This work demonstrated dynamic tuning of the emissive excited states of copper nanoclusters through the efficient engineering of ligands.

10.
Indian J Biochem Biophys ; 50(5): 462-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24772969

RESUMO

Preeclampsia, a pregnancy-related hypertensive disorder, is one of the leading causes of fetal and maternal mortality and morbidity globally. Angiogenic growth factors, including vascular endothelial growth factor (VEGF) and placental growth factor (P1GF) are involved in the generation of new blood vessels required for placental development and physiological functions, while nitric oxide (NO) acts as vasodilator and also plays a role in angiogenesis. The objective of this study was to evaluate the role of NO, angiogenic growth factors (VEGF and PIGF) and other biochemical parameters in the development of preeclampsia among pregnant mothers. A complete clinical history, including anthropometric measurements and biochemical investigations, including renal function tests, liver function tests and lipid profile were performed among twenty preeclampsia patients aged 19 to 32 yrs. Results were compared with age-matched normotensive pregnant mothers. The body weight, body mass index (BMI), blood pressure, concentrations of urea, uric acid and triglyceride and activities of transaminase enzymes (aspartate transaminase, AST and alanine transaminase, ALT) in serum were significantly higher (p < 0.05) than normotensive subjects. Serum concentrations of VEGF, P1GF and NO were significantly decreased (p < 0.005) in preeclamptic patients. NO was found negatively correlated with body weight (r = -0.369, p < 0.05), systolic blood pressure (r = -0.822, p < 0.005), diastolic blood pressure (r = -0.714, p < 0.005) and was positively correlated with VEGF (r = 0.464, p < 0.005) and P1GF (r = 0.546, p < 0.005). VEGF and P1GF showed significant (p < 0.005) negative correlation with systolic and diastolic blood pressure and PIGF was significantly correlated with triglyceride (r = -0.379). However, no significant correlation was observed between the VEGF and P1GF. In conclusion, the results indicated that body weight, triglyceride, angiogenic growth factors and NO might associate with preeclampsia development.


Assuntos
Óxido Nítrico/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/metabolismo , Proteínas da Gravidez/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Peso Corporal , Estudos de Casos e Controles , Feminino , Humanos , Mães , Fator de Crescimento Placentário , Pré-Eclâmpsia/fisiopatologia , Gravidez , Triglicerídeos/sangue , Adulto Jovem
11.
Org Lett ; 25(42): 7733-7738, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37853522

RESUMO

An efficient photocatalytic para- and ortho-selective amination and aminative dearomatization of phenols, naphthols, and anilines with azodicarboxylates was developed using riboflavin tetraacetate (RFTA) as an organic photocatalyst. The site selectivity was controlled using tetrabutylammonium bromide (TBAB), which also acts as a phase transfer catalyst. The reaction conditions are simple and mild, giving high regioselectivity with good to excellent yields. A broad substrate scope and nice functional group tolerance with scalability and post-functionalization make this protocol both useful and regioselective.

12.
Cureus ; 14(1): e21559, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35106262

RESUMO

INTRODUCTION: Diabetes is a recognised risk for several chronic and acute illnesses, including increased complications in surgery for oesophageal cancer. Our primary aim is to determine the impact of diabetes on postoperative surgical and medical complications after oesophagectomy. METHODS: All oesophagectomies for malignancy as reflected in the 2016-2018 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) datasets were extracted and analysed. Current Procedural Terminology (CPT) codes used were 1) open procedures (43107, 43108, 43112, 43113, 43116, 43117, 43118, 43121, 43122, and 43123) and 2) hybrid procedures (43186, 43287, and 43288). Logistic regression models examined associations between diabetic status and adverse outcomes. The associations were adjusted for sex, race, age group, operation year, CPT code, body mass index (BMI), smoking, congestive heart failure, antihypertensives, renal failure, and dyspnoea. RESULTS: Two thousand five hundred and thirty-eight oesophagectomies were identified. 86.45% (n=2,194) underwent open procedures and 13.55% (n=344) had hybrid procedures. There were 177 insulin-dependent diabetics (IDDM) and 320 (12.61%) non-insulin-dependent diabetics (NIDDM). 84.14% were male and 77.74% were Caucasian. 89.48% of the patients were between 50 and 79 years of age. 40.27% experienced postoperative complications. Medical complications (odds ratio [OR]: 1.7, p-value: 0.002), surgical complications (OR: 1.9, p-value: <0.001), wound complications (OR: 2.9, p-value: <0.001), and anastomotic leaks (OR: 2.4, p-value: <0.001) were more common in diabetic patients. Subgroup analysis showed that in hybrid procedures, there is a statistically significant increase in the OR of surgical complications (OR: 3.61, p-value: 0.05), medical complications (OR: 3.76, p-value: 0.04), and anastomotic leak (OR: 3.49, p-value: 0.27) in IDDM as compared to NIDDM. CONCLUSION: Insulin-dependent diabetes doubles the risk of all major complications compared to nondiabetics. When considering surgical approach and diabetic status (IDDM vs nondiabetics, NIDDM vs nondiabetics), the risk of complications further doubles for hybrid oesophagectomies compared to open procedures.

13.
ANZ J Surg ; 92(9): 2143-2148, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35903966

RESUMO

INTRODUCTION: Hepatobiliary and pancreatic surgery is frequently complicated by surgical site infections (SSI) with significant postoperative morbidity and mortality rates contributing to the economic burden on healthcare. Advancements in operative techniques to prevent SSI are gaining traction in clinical practice. This study compares the effectiveness of the 'loop and drain technique (LDT)', a combination method utilizing a continuous subcutaneous vessel loop and subcuticular suture for surgical wound closure in patients undergoing upper gastrointestinal surgery at a Metropolitan Hospital in Sydney. METHODS: A retrospective review of patients who underwent an upper gastrointestinal procedure was conducted at Bankstown-Lidcombe hospital between 2017 and 2019. There were 77 patients in the LDT group and 123 patients included in the control group. The primary outcome assessed was the rate of SSI. Secondary outcomes included length of stay (LOS) and drainage of surgical site infections. RESULT: Two hundred adult patients were treated for an upper gastrointestinal procedure. The most common operation was a Whipple procedure (35.0%). The rate of SSI was 12.5% with all these patients receiving intravenous antibiotics. The LDT cohort had a significantly lower rate of SSI compared to their counterparts (3.9% vs. 17.9%, P = 0.004). CONCLUSION: The LDT method is associated with a decreased incidence of SSI and should be considered as a cost-effective operative technique to improve patient outcomes after upper gastrointestinal surgery.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Infecção da Ferida Cirúrgica , Adulto , Antibacterianos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Drenagem/efeitos adversos , Humanos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Suturas/efeitos adversos
14.
J Med Cases ; 12(5): 186-189, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34434455

RESUMO

Cholelithiasis is a common gastrointestinal pathology with a prevalence of over 6% in the USA. Symptomatic patients can develop cholangitis, biliary colic, pancreatitis and cholecystitis. Surgical management involves laparoscopic or open cholecystectomy. Stones within the common bile duct can be treated with endoscopic retrograde cholangiopancreatography (ERCP). Well-known ERCP complications include pancreatitis, perforation, bleeding and cholangitis. Hepatic hematomas as a complication of ERCP are extremely rare, with fewer than 50 reported cases in the literature. Approximately 22% have required operative management. We present an extremely rare case of ERCP-associated subcapsular hepatic hematoma in a 43-year-old lady that was initially non-operatively managed. She did not improve with antibiotics alone and underwent attempted interventional radiology drainage. Despite this, due to on-going sepsis, the patient underwent laparoscopic necrosectomy and drain placement with continued post-operative irrigation. After a long course of antibiotics and drain irrigation, the patient was discharged with repeated computed tomography imaging showing almost total resolution of the infected collection. This case highlights the extreme rarity of surgical management for post-ERCP subcapsular hepatic hematoma and its successful outcome.

15.
BMJ Case Rep ; 14(8)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34353824

RESUMO

A 73-year-old woman presented with fever and right flank pain. The admission was complicated by sepsis, myocardial ischaemia and an upper gastrointestinal bleed. A gastroscopy eventually demonstrated a large antral adenocarcinoma. Further imaging showed no evidence of metastasis, but demonstrated a large segment 3 hepatic abscess. At laparotomy, a hepatogastric fistula (HGF) was noted and a synchronous subtotal gastrectomy and left lateral liver sectionectomy was performed. Final histology showed complete resection of the gastric cancer (T4bN2) and confirmed the presence of the fistula. The patient was discharged 10 days later. She passed away 6 months later with local recurrence, hepatic and pulmonary metastasis. We include a review summarising the other causes of HGF in the literature.


Assuntos
Adenocarcinoma , Fístula , Fístula Gástrica , Abscesso Hepático , Neoplasias Gástricas , Adenocarcinoma/complicações , Adenocarcinoma/cirurgia , Idoso , Feminino , Fístula Gástrica/diagnóstico por imagem , Fístula Gástrica/etiologia , Humanos , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/etiologia , Recidiva Local de Neoplasia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia
16.
Artigo em Inglês | MEDLINE | ID: mdl-34930756

RESUMO

Ménétrier's disease (MD) is a rare gastropathy characterised by giant rugal folds which can present with nausea, vomiting, abdominal pain and protein losing gastropathy. We report a 21-year-old woman with comorbid MD and ulcerative colitis (UC). Management was complicated by limited treatment options for MD, significant symptom burden, worsening nutrition and difficulty determining which disease was the predominant cause of symptoms. Since age 18 the patient experienced recurrent UC flares characterised by diarrhoea, persistent vomiting and corticosteroid dependence. Endoscopic assessment demonstrated concurrent MD and active UC. Octreotide and cetuximab were trialled given persistent hypoalbuminaemia and suspicion for MD associated protein-losing gastropathy. UC management comprised dose-optimised infliximab and methotrexate. Repeat endoscopic assessment demonstrated improvement in UC without corresponding improvement in symptoms or hypoalbuminaemia. Nasojejunal feeding and parenteral nutrition failed to significantly improve nutritional status and accordingly the patient proceeded to radical total gastrectomy. Postoperatively, MD-associated symptoms and hypoalbuminemia resolved completely.


Assuntos
Colite Ulcerativa , Gastrite Hipertrófica , Hipoalbuminemia , Gastropatias , Adolescente , Adulto , Colite Ulcerativa/complicações , Colite Ulcerativa/cirurgia , Feminino , Gastrectomia/efeitos adversos , Gastrite Hipertrófica/complicações , Gastrite Hipertrófica/diagnóstico , Gastrite Hipertrófica/cirurgia , Humanos , Hipoalbuminemia/complicações , Hipoalbuminemia/cirurgia , Gastropatias/complicações , Gastropatias/cirurgia , Vômito , Adulto Jovem
17.
Cureus ; 12(3): e7236, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32190530

RESUMO

The traditional management of pancreatic pseudocyst (PP) is surgical drainage; however, there is significant morbidity associated with this approach. An endoscopic ultrasound (EUS)-guided transgastric endoscopic approach is preferred if there is favourable access to the PP. This case report describes a rare complication of an EUS-guided transgastric drainage of a PP secondary to a suboptimally positioned stent. Significant soiling of the peritoneal cavity by pancreatic juices and gastric contents occurred due to leakage around the stent puncture sites. A novel technique using an infant feeding tube is described to inflate the collapsed PP and facilitate definitive surgical cystogastrostomy. A literature review and discussion surrounding the safety of endoscopic decompression and the type of stent utilised is also presented.

18.
Biotechnol Bioeng ; 102(1): 200-8, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18683263

RESUMO

The amplification of gltA gene encoding citrate synthase of TCA cycle was required for the efficient conversion of acetyl-CoA, generated during vanillin production from ferulic acid, to CoA, which is essential for vanillin production. Vanillin of 1.98 g/L was produced from the E. coli DH5alpha (pTAHEF-gltA) with gltA amplification in 48 h of culture at 3.0 g/L of ferulic acid, which was about twofold higher than the vanillin production of 0.91 g/L obtained by the E. coli DH5alpha (pTAHEF) without gltA amplification. The icdA gene encoding isocitrate dehydrogenase of TCA cycle was deleted to make the vanillin producing E. coli utilize glyoxylate bypass which enables more efficient conversion of acetyl-CoA to CoA in comparison with TCA cycle. The production of vanillin by the icdA null mutant of E. coli BW25113 harboring pTAHEF was enhanced by 2.6 times. The gltA amplification of the glyoxylate bypass in the icdA null mutant remarkably increased the production rate of vanillin with a little increase in the amount of vanillin production. The real synergistic effect of gltA amplification and icdA deletion was observed with use of XAD-2 resin reducing the toxicity of vanillin produced during culture. Vanillin of 5.14 g/L was produced in 24 h of the culture with molar conversion yield of 86.6%, which is the highest so far in vanillin production from ferulic acid using recombinant E. coli.


Assuntos
Acetilcoenzima A/metabolismo , Benzaldeídos/metabolismo , Ácidos Cumáricos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Adsorção , Benzaldeídos/toxicidade , Biotecnologia/métodos , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Deleção de Genes , Dosagem de Genes , Glioxilatos/metabolismo , Isocitrato Desidrogenase/genética , Poliestirenos
19.
JGH Open ; 3(1): 89-90, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30834346

RESUMO

Humans usually acquire Fasciola infection by eating contaminated aquatic vegetation, such as watercress. After ingestion, Fasciola metacercariae excyst in the duodenum. In contrast to other liver flukes (Clonorchis and Opisthorchis) that migrate through the ampulla of Vater and ascend the biliary tree, Fasciola metacercariae penetrate the duodenal wall, migrate through the peritoneal cavity, and enter the liver. After a period of migrating randomly through the liver parenchyma, they eventually reach the larger biliary ducts and mature into adults. We present a case that illustrates this migration route of Fasciola.

20.
Brain Res ; 1139: 195-200, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17291463

RESUMO

This study reveals that, in contrast to dopamine (DA), 3,4 dihydroxyphenylacetic acid (DOPAC) during in vitro incubation up to 2 h causes only marginal inhibition of rat brain mitochondrial respiratory chain activity, a minimal loss of protein free thiols and very little quinoprotein adduct formation. The damaging effects of DA on brain mitochondria are, however, conspicuous and apparently mediated by quinone oxidation products generated by autoxidation of DA as well as catalyzed by a mitochondrial activity, inhibitable by clorgyline (2.5-10 microM) and cyanide (1 mM).


Assuntos
Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Benzoquinonas/metabolismo , Dopamina/metabolismo , Mitocôndrias/metabolismo , Doença de Parkinson/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Animais , Encéfalo/enzimologia , Transporte de Elétrons/fisiologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Oxirredução , Doença de Parkinson/enzimologia , Ratos , Ratos Endogâmicos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa