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1.
Small ; 20(23): e2305958, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38169107

RESUMO

Simultaneous electroreduction of CO2 and H2O to syngas can provide a sustainable feed for established processes used to synthesize carbon-based chemicals. The synthesis of MOx/M-N-Cs (M = Ni, Fe) electrocatalysts reported via one-step pyrolysis that shows increased performance during syngas electrosynthesis at high current densities with adaptable H2/CO ratios, e.g., for the Fischer-Tropsch process. When embedded in gas diffusion electrodes (GDEs) with optimized hydrophobicity, the NiOx/Ni-N-C catalyst produces syngas (H2/CO = 0.67) at -200 mA cm-2 while for the FeOx/Fe-N-C syngas production occurs at ≈-150 mA cm-2. By tuning the electrocatalyst's microenvironment, stable operation for >3 h at -200 mA cm-2 is achieved with the NiOx/Ni-N-C GDE. Post-electrolysis characterization revealed that the restructuring of the catalyst via reduction of NiOx to metallic Ni NPs still enables stable operation of the electrode at -200 mA cm-2, when embedded in an optimized microenvironment. The ionomer and additives used in the catalyst layer are important for the observed stable operation. Operando Raman measurements confirm the presence of NiOx during CO formation and indicate weak adsorption of CO on the catalyst surface.

2.
Acta Parasitol ; 68(1): 70-83, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36380160

RESUMO

PURPOSE: The relationship between the genetic diversity of Blastocystis and immune surveillance in precancerous colons with blastocystosis is still under investigation. This study aimed to identify the genetic Blastocystis variants among 54 symptomatic human isolates and their relationship to mucosal immune surveillance in the precancerous polyps of experimentally infected rats. METHODS: Polymerase chain reaction and high-resolution melting (PCR/HRM) curves discriminated human symptomatic Blastocystis isolates into subtypes (STs)/intrasubtypes, which were orally administered to rats to induce experimental infection. Then, the mucosal immune responses of the infected colons were evaluated in relation to polyp formation through immunostaining to identify mucus MUC2 and determine mucosal immune cell (goblet, lymphocyte and mast) counts, secretory IgA levels and parasitic intestinal invasion. RESULTS: ST1, ST3, and ST4 were found in 18.5% (10/54), 54.7% (29/54), and 27.8% (15/54) of the samples, respectively. Then, the HRM curve discriminated ST3 into the wild, mutant, and heterozygous [17/54 (31.5%), 5/54 (9.3%), and 7/54 (12.9%)] intrasubtypes. ST1 and ST4 had no genetic variations. Precancerous polyps were detected in the colons of 40.5% of the infected rats. ST1 constituted 14.7% of these cases, while the wild, mutant, and heterozygous intrasubtypes of ST3 showed polyps in 12.9%, 5.5%, and 5.5% of cases, respectively. Only 1.9% of the polyps were related to ST4. MUC2 showed weak immunostaining in 44.5% of the infected colons, and 38.9% were polyp inducers. Low goblet cell numbers and high interepithelial lymphocyte counts were significantly associated with polyp formation, particularly with ST1 and wild ST3. Among the polyp inducers, high numbers of mast cells were detected in wild ST3 and ST4, while a low number was found with heterozygous ST3. The level of secretory IgA was low in polyp-inducing STs. Most of the results were statistically significant. CONCLUSION: Immunosurveillance showed a potential relationship between ST1 and the ST3 intrasubtypes and precancerous polyps. This relationship may provide insight into the prevention and/or development of new immunotherapeutic strategies to combat colorectal cancer.


Assuntos
Infecções por Blastocystis , Blastocystis , Lesões Pré-Cancerosas , Humanos , Animais , Ratos , Blastocystis/genética , Fezes/parasitologia , DNA de Protozoário/genética , Infecções por Blastocystis/parasitologia , Filogenia
4.
Artigo em Inglês | MEDLINE | ID: mdl-36816159

RESUMO

Genetic mutations can present with cardiomyopathies and ventricular arrhythmias in young population in the absence of other cardiac risk factors. LMNA genetic mutation is one of the causes of dilated cardiomyopathy (DCM) which can present with conduction abnormalities and arrhythmias. We present a case of LMNA genetic mutation in an African American male who presented with ventricular tachycardia in the absence of dilated cardiomyopathy initially mimicking cardiac sarcoidosis. Diagnostic challenges included initial impression of cardiac sarcoidosis as suggested by cardiac MRI, but negative tissue pathology on endomyocardial biopsy and negative activity on FDG PET scan. Treatment involved initiation of beta blocker and an implantable cardiac defibrillator placement for secondary prevention.

5.
Oxid Med Cell Longev ; 2018: 8104165, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29686746

RESUMO

Diabetes mellitus is one of the metabolic diseases having several complications. Nigella sativa oil (NSO) might have beneficial effects in the treatment of diabetic complications. Thirty-two mature male Wistar rats were equally divided into four experimental groups: control, control NSO 2 mL/kg, streptozotocin- (STZ-) induced diabetic, and diabetic (STZ-induced) treated with oral NSO 2 mg/kg for 30 days. Fasting blood glucose (FBG), insulin, and lipid profile levels were determined. Pancreatic and hepatic tissues were used for catalase and GSH. Histopathology, hepatic glycogen contents, insulin immunohistochemistry, and pancreatic islet morphometry were performed. NSO 2 mL/kg was noticed to decrease (P < 0.05) FBG and increase (P < 0.05) insulin levels in diabetic rats than in diabetic nontreated animals. Lipid profile showed significant (P < 0.5) improvement in diabetic rats that received NSO 2 mL/kg than in the diabetic group. Both pancreatic and hepatic catalase and GSH activities revealed a significant (P < 0.05) increment in the diabetic group treated with NSO than in the diabetic animals. NSO improved the histopathological picture and hepatic glycogen contents of the diabetic group as well as increased (P < 0.05) insulin immunoreactive parts % and mean pancreatic islet diameter. NSO exerts ameliorative and therapeutic effects on the STZ-induced diabetic male Wistar rats.


Assuntos
Benzoquinonas/química , Diabetes Mellitus Experimental/induzido quimicamente , Insulina/sangue , Nigella sativa/química , Estreptozocina/efeitos adversos , Animais , Diabetes Mellitus Experimental/patologia , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar
6.
Surg Neurol Int ; 9: 4, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29399376

RESUMO

BACKGROUND: The ligamenta flava can undergo ossification and calcification resulting in myelopathy. Only seven cases of ligamentum flavum ossification in association with hypoparathyroidism have been reported, most of which had concurrent osseous changes in other spinal ligaments. Here, we report a patient with hypoparathyroidism who presented with ligamentum flavum ossification causing both cervical and thoracic myelopathy. CASE DESCRIPTION: A 43-year-old male presented with backache, urinary retention, and lower limb weakness for the last few days. Magnetic resonance imaging scan showed ossification of the ligamentum flavum in the cervical and thoracic regions, with severe spinal stenosis. Following spinal decompressive surgery, the patient made a complete recovery. Primary hypoparathyroidism was found to be the underlying cause for ligamentum flavum ossification. CONCLUSION: Ossification of ligamentum flavum secondary to hypoparathyroidism should be considered as a possible cause of myelopathy in all patients presenting with symptoms of spinal cord compression.

8.
J Plast Reconstr Aesthet Surg ; 67(10): 1322-32, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24939827

RESUMO

BACKGROUND: The pre-malignant skin lesion lentigo maligna (LM) presents a particular challenge. Pathologists demonstrate poor diagnostic concordance and often struggle to assess whether excision margins are truly negative. This can lead to equivocal histology reports and a lack of clear guidance with which surgeons may rationalise their surgical management plans. Based upon the biological principle that tumour burden increases the chance of recurrence, we propose a shift in diagnostic paradigm, using melanocyte count (MC) at an excision margin to predict LM recurrence. METHODS: This retrospective study reviewed all cases of LM from a regional UK melanoma centre (1996-2011), to include 167 excisions, from 99 patients. Pathology slides were assessed for MC (blinded) at the most affected margin. Seven secondary markers of neoplasia were additionally evaluated. Logistic regression analysis was used to model the relationship between MC and recurrence. RESULTS: MC is a strong predictor of LM recurrence (p < 0.0001). A regression curve predicts risk for individual MCs, which may also be divided into three risk strata; low (0-11% [MC 0-20]), intermediate (15-89% [MC 21-30]), and high risk (92-100% [MC ≥ 31]). MC misclassified 0.6% of cases in the low and high risk groups compared with 21% for pathologists, who were also equivocal for 18% of excisions. MC's inter-rater concordance was high (>0.9). The secondary factors were all independently associated with recurrence, but failed to improve predictive ability supplementary to MC. CONCLUSIONS: MC confidently predicts LM recurrence and is more accurate and reliable, whilst also reducing the uncertainty of current pathology assessment. Risk estimates for any given MC can be easily charted using the regression curve graph, where confidence interval and risk group boundaries demonstrate the degree of certainty associated with any given prediction. This change in approach is congruent with tumour behaviour. A recurrence 'tipping point' corresponds to the sharp risk increase across the intermediate group's narrow band of MC.


Assuntos
Sarda Melanótica de Hutchinson/patologia , Melanócitos/citologia , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/patologia , Área Sob a Curva , Contagem de Células , Humanos , Modelos Logísticos , Medição de Risco
9.
Case Rep Oncol Med ; 2012: 352401, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23320219

RESUMO

A 72-year-old man presented with painless frank haematuria. Investigations included intravenous urogram and abdominal/pelvic CT which revealed a marked focal thickening of the wall of the inferior aspect of the left renal pelvis extending into the lower pole calyx and into the pelviureteric junction resulting in left hydronephrosis. Urine cytology demonstrated clusters of malignant keratinised squamous cells and schistosome ova. He underwent left laparoscopic radical nephroureterectomy and histology revealed moderately differentiated keratinising squamous cell carcinoma in the renal pelvis.

10.
J Craniofac Surg ; 21(3): 905-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20485078

RESUMO

The reconstruction of full-thickness scalp defects remains a surgical challenge. Different types of reconstruction had varying success including the use of dermal regeneration template (DRT). We reviewed the surgical outcome of 30 patients who underwent application of DRT for resurfacing of full-thickness scalp defects when the pericranium was excised and the outer cortex of the calvarial bone was burred after the excision of scalp neoplasm. This was a retrospective review of 30 patients who had scalp reconstruction with DRT undertaken by the senior author between October 2004 and June 2007. The mean age of patients in our series was 63 years (37-91 years). There were 14 men and 16 women. The indications for re-excision and DRT reconstruction in 28 patients were close margins and aggressive tumor type, whereas 2 patients had a recurrence. The mean defect size was 95 cm2 (16-275 cm2). The second stage of the reconstruction occurred on postoperative day 42 (postoperative days 27-62). The mean follow-up period was 14 months. Two patients had minor complications. For both stages, the combined average operative time was 128 minutes. The use of DRT is a rung of the reconstructive ladder that deserves consideration. In our series of 30 patients who required secondary reconstruction of complex scalp defects, the use of DRT has been seen to provide safe and durable soft-tissue cover for full-thickness scalp defects. The reduced operative time and inpatient stay are desirable characteristics particularly in elderly patients with multiple comorbidities.


Assuntos
Sulfatos de Condroitina , Colágeno , Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos de Cirurgia Plástica/instrumentação , Couro Cabeludo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento
11.
J Craniofac Surg ; 21(2): 561-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20216437

RESUMO

The 2-stage Nagata method for auricular reconstruction in patients with microtia is a widely accepted technique. We have modified this technique into a single-stage procedure for the reconstruction of acquired segmental auricular defects. A prospective analysis was made of the senior author's first 20 consecutive cases over a 4-year period (February 2004 to February 2008). The mean age of patients in our series was 34 years (range, 17-59 years). There were 15 males and 5 females; 13 were right-sided and 7 were left-sided segmental auricular defects. Five patients had had previous auricular reconstruction including local flaps and grafts. Costal cartilage harvest was ipsilateral to the defect in all cases. All 20 patients underwent a single-stage modification of the Nagata technique. Mean duration of surgery was 8.56 hours (range, 5.5-11.5 hours). Mean hospital stay was 7.6 days (range, 4-19 days). Mean time from initial surgery to a satisfactory completion of treatment was 21 months. Overall, a low complication rate and high patient satisfaction were observed in this series. We believe the single-stage modified Nagata technique offers consistent high-quality results in the treatment of acquired segmental auricular defects. All patients undergoing autologus ear reconstruction need to be assessed in a multidisciplinary setting and should be offered all other options for treatment.


Assuntos
Pavilhão Auricular/cirurgia , Deformidades Adquiridas da Orelha/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Cartilagem/transplante , Estudos de Coortes , Pavilhão Auricular/lesões , Neoplasias da Orelha/cirurgia , Fáscia/transplante , Feminino , Seguimentos , Hospitalização , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Satisfação do Paciente , Estudos Prospectivos , Estudos Retrospectivos , Transplante de Pele/métodos , Retalhos Cirúrgicos , Fatores de Tempo , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento , Adulto Jovem
12.
Ann Afr Med ; 7(1): 24-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18702245

RESUMO

BACKGROUND: This study examines the diagnosis of malaria and pattern of prescription of antimalarial drugs in the most vulnerable age group (the under 5 children) in the study environment in order to identify the possible shortcomings and suggest solutions so as to improve the treatment outcome in future. METHODS: The hospital records of 430 children with malaria infection admitted for treatment in a chosen tertiary health facility between January to December 2005 were selected for study. Forty-eight case records were excluded due to incomplete information. Data on demographic, clinical features of disease, diagnostic procedures, drug administration and the treatment out come were collected from the patients' records. RESULTS: Analysis of the data revealed that more male (213) than female (169) children were admitted for malaria treatment: Fever with convulsion (55.8%) was the commonest presenting symptoms, and anemia was the most frequent complications of malaria recorded. Chloroquine was found to be the most prescribed antimalarial agent and overall antemisinin-based drug was prescribed either as a first or second line treatment in only 18.2% of the cases. The death rate recorded was 16%. CONCLUSION: The pattern of antimalarial drugs prescription in the study center in most cases did not meet the recommended guidelines. The prescriptions were predominantly chloroquine, instead of artemisinin based. The death rate was comparatively high. Measures to raise the level of awareness among the practitioners on the current National policy on malaria treatment through seminars and workshops were suggested.


Assuntos
Antimaláricos/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Malária/tratamento farmacológico , Plasmodium/efeitos dos fármacos , Padrões de Prática Médica/estatística & dados numéricos , Anemia/etiologia , Animais , Antimaláricos/efeitos adversos , Pré-Escolar , Estudos Transversais , Feminino , Fidelidade a Diretrizes , Hospitais Universitários , Humanos , Incidência , Lactente , Recém-Nascido , Malária/complicações , Malária/diagnóstico , Malária/mortalidade , Masculino , Nigéria/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento
13.
Ann. afr. med ; 7(1): 24-28, 2008.
Artigo em Inglês | AIM (África) | ID: biblio-1258964

RESUMO

Background: This study examines the diagnosis of malaria and pattern of prescription of antimalarial drugs in the most vulnerable age group (the under 5 children) in the study environment in order to identify the possible shortcomings and suggest solutions so as to improve the treatment outcome in future. Methods: The hospital records of 430 children with malaria infection admitted for treatment in a chosen tertiary health facility between January to December 2005 were selected for study. Forty-eight case records were excluded due to incomplete information. Data on demographic; clinical features of disease; diagnostic procedures; drug administration and the treatment out come were collected from the patients' records. Results: Analysis of the data revealed that more male (213) than female (169) children were admitted for malaria treatment: Fever with convulsion (55.8) was the commonest presenting symptoms; and anemia was the most frequent complications of malaria recorded. Chloroquine was found to be the most prescribed antimalarial agent and overall antemisinin-based drug was prescribed either as a first or second line treatment in only 18.2of the cases. The death rate recorded was 16. Conclusion: The pattern of antimalarial drugs prescription in the study center in most cases did not meet the recommended guidelines. The prescriptions were predominantly chloroquine; instead of artemisinin based. The death rate was comparatively high. Measures to raise the level of awareness among the practitioners on the current National policy on malaria treatment through seminars and workshops were suggested


Assuntos
Antimaláricos , Criança , Malária/terapia , Nigéria , Preparações Farmacêuticas , Prescrições , Convulsões
14.
Respir Care ; 46(7): 702-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11403702

RESUMO

Granular cell tumor (GCT) of the lung is a rare tumor, constituting less than 10% of all GCTs. It is a multicentric tumor and infiltrates into adjoining tissue, but malignant GCT of the lung has not been reported. Diagnosis is usually obtained with bronchoscopic biopsy. Treatment options include bronchoscopic extirpation, laser therapy, and sleeve resection. We present a case of GCT co-existing with adenocarcinoma of the lung and review the literature.


Assuntos
Adenocarcinoma Bronquioloalveolar/complicações , Neoplasias Pulmonares/complicações , Granuloma de Células Plasmáticas Pulmonar/complicações , Adulto , Feminino , Humanos
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