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Microwave-steam activation (MSA), an innovative pyrolysis approach combining the use of microwave heating and steam activation, was investigated for its potential production of high grade activated carbon (AC) from waste palm shell (WPS) for methylene blue removal. MSA was performed via pyrolytic carbonization of WPS to produce biochar as the first step followed by steam activation of the biochar using microwave heating to form AC. Optimum yield and adsorption efficiency of methylene blue were obtained using response surface methodology involving several key process parameters. The resulting AC was characterized for its porous characteristics, surface morphology, proximate analysis and elemental compositions. MSA provided a high activation temperature above 500⯰C with short process time of 15â¯min and rapid heating rate (≤150⯰C/min). The results from optimization showed that one gram of AC produced from steam activation under 10â¯min of microwave heating at 550⯰C can remove up to 38.5â¯mg of methylene blue. The AC showed a high and uniform surface porosity consisting high fixed carbon (73â¯wt%), micropore and BET surface area of 763.1 and 570.8â¯m2/g respectively, hence suggesting the great potential of MSA as a promising approach to produce high grade adsorbent for dye removal.
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Carvão Vegetal , Vapor , Adsorção , Micro-Ondas , PiróliseRESUMO
Detailed parallels described between lens fiber cell and neuron morphology, sub-cellular structure, and molecular biology include striking similarities in the ultrastructure of their vesicle transport machinery and the membrane protrusions that occur along the lateral surfaces of both cell types. α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartate receptor (NMDA) glutamate receptors (AMPARs/NMDARs) are the predominant receptors in neurons. These receptors have fundamental roles in neuron morphogenesis as well as neuron physiology and dynamic cell signaling, and specifically at dendritic spines. As a result, AMPAR and NMDAR dysregulation underlies several primary neural disorders that have also shown epidemiological associations with cataract. Previously, we demonstrated AMPAR GluA1 and REST (RE-1 silencing transcription factor)-regulated GluA2 subunits are expressed in the lens, and showed C-terminal phospho-tyrosine-GluA2, and striatal-enriched tyrosine phosphatase (STEP), as well as GluA2 Q/R RNA editing in lenses similar to neurons. Here, we demonstrated that REST-regulated NMDAR NR1, NR2A, and NR2B are also expressed in lenses and localize predominantly in fiber cell membranes, consistent with REST transcription factors, as well as miR-124 and other REST gene targets identified in the lens. We also showed NR2B Tyr-1472 phosphorylation occurs in lens. These p-Tyr-GluA2 and p-Tyr-NR2B phosphorylation events are linked with membrane insertion regulated by STEP. We next determined that NR1 transcripts that include exon 5 are produced in lens consistent with Fox-1 RNA binding protein isoforms linked with this alternative splicing event, and shown to be expressed in lens as well as brain. These findings provide further evidence that fundamental neuronal morphogenetic programs, and hallmark neuronal gene expression and modes of regulation, are shared with elongated fiber cells of the lens.
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Cristalino/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Coelhos , Receptores de N-Metil-D-Aspartato/químicaRESUMO
This retrospective study evaluates the prognostic value of pulmonary artery oxygen saturation (PA O2) among patients who undergo mechanical intervention for pulmonary embolism (PE). Patients who died within 90 days had less PA O2, and a greater percentage of patients with a PA O2 of <50 died within 90 days of intervention. Regression analysis revealed an association of PA O2 with mortality that held true despite accounting for Pulmonary Embolism Severity Index (PESI) score and type of endovascular intervention. Receiver operator curve testing revealed PA O2 <50% to be inferior to PESI score but superior to Bova score in predicting mortality after mechanical PE intervention, with the combination of PA O2 <50% and PESI outperforming PESI and PA O2 in predicting mortality. Our pilot evaluation suggests preintervention PA O2 <50% to be associated with increased risk of all-cause mortality and may help identify patients at greatest risk of deterioration.
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Artéria Pulmonar , Embolia Pulmonar , Humanos , Prognóstico , Estudos Retrospectivos , Medição de Risco , Saturação de Oxigênio , Valor Preditivo dos Testes , Embolia Pulmonar/complicações , Índice de Gravidade de DoençaRESUMO
Background: There is significant debate on whether large-bore thrombectomy (LBT) or catheter-directed thrombolysis (CDT) is superior for the treatment of intermediate- and high-risk pulmonary embolism (PE) while employing an early invasive strategy through endovascular therapies. Methods: Between 2018 and 2021, 147 patients who presented to our institution with acute intermediate- or high-risk PE and had undergone PE Response Team-guided endovascular intervention with either LBT (Inari FlowTriever) or CDT (EKOSonic) were retrospectively reviewed. Data on the patients' clinical characteristics, comorbidities, serum biomarkers, hemodynamics, and imaging characteristics were obtained. The primary outcome was all-cause mortality; the secondary outcomes were all-cause readmission, readmission for PE, and length of stay in the intensive care unit and hospital. The safety outcome of procedure-related bleeding was evaluated. Kaplan-Meier curves were used to estimate the cumulative event rate. Multivariate Cox-proportional hazard regression and inverse propensity weighting were used to adjust for confounders. Results: The median age of the patients was 63 (IQR, 53-73) years, and 48.3% of the patients were women. Patients in the LBT group had a higher PE Severity Index score (LBT vs CDT: median, 132 vs 108; P = .015) and greater prevalence of malignancy (LBT vs CDT: median, 22.7% vs 6%; P = .011). After propensity matching for baseline characteristics, there was no significant difference in all-cause mortality (LBT vs CDT: median, 15.8% vs 9.1%; hazard ratio, 0.64; 95% CI, 0.21-1.98; P = .442) for up to 1 year. The secondary outcomes or safety end points were also similar between the 2 interventions. An exploratory analysis showed elevated PE Severity Index scores, lower systolic blood pressures, and higher lactic acid levels to be associated with an increased risk of early death at 30 days. Conclusions: In this retrospective cohort study, there was no significant difference in the cumulative event rate of all-cause mortality between LBT and CDT. Further studies are needed to evaluate the use of LBT versus CDT versus noninvasive therapy to understand outcomes and appropriate patient selection among those with intermediate- and high-risk PE.
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BACKGROUND: The prevalence and prognosis of previously undiagnosed angina pectoris (AP) in the absence of established cardiovascular disease (CVD) are unknown. This study sought to determine the prevalence and prognosis of previously undiagnosed AP in the absence of established CVD in the United States. METHODS: Data derived from the National Health and Nutrition Examination Survey (2001-2018) and the Rose Angina Questionnaire (RAQ) were used to identify AP among participants ≥ 40 years without established CVD. Determinants of previously undiagnosed AP (AP undiagnosed prior to RAQ analysis) and predictors of all-cause mortality were identified using multivariable logistic regression analysis and the Cox proportional hazard model. RESULTS: Of the 27,506 participants eligible for analysis, 621 participants had previously undiagnosed AP. Thus, the prevalence of previously undiagnosed AP was 1.99% (95% CI 1.79-2.20). Female gender, poverty, < high school education, hypertension, cigarette smoking, and obesity were independent predictors of previously undiagnosed AP. All-cause mortality rates were 1.71 per 1000 person months for participants with previously undiagnosed AP and were 1.08 per 1000 person months to those without previously undiagnosed AP (p = 0.003). CONCLUSIONS: The prevalence of previously undiagnosed AP in the United States is 1.99% in persons ≥ 40 years of age without established CVD. Previously undiagnosed AP in those without established CVD was an independent predictor of all-cause mortality.
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Doenças Cardiovasculares , Humanos , Estados Unidos/epidemiologia , Feminino , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Prevalência , Inquéritos Nutricionais , Angina Pectoris/diagnóstico , Angina Pectoris/epidemiologia , PrognósticoRESUMO
The lower limit of soluble zinc content that can possibly be applied onto a wounded skin as a healing promoter was not known. This study examined skin wound healing process of rats inflicted by partial thickness thermal burn wound as a function of applied soluble zinc contents (0.1 ml of zinc chloride solution 0.01% (w/w) or 5.0% (w/w)). The size, surface morphology and histological profiles of wound beds of untreated rats and those treated with zinc chloride solutions were characterized. A soluble zinc content as low as 10.5 µg/cm2 of skin negated skin wound healing when compared to the untreated rats. This was alarming as the commercial products currently in the market are formulated with a high level of zinc content. Albeit the zinc salt employed was water-insoluble, a minute fraction of soluble zinc might be available to the treatment sites. This could be partially responsible for the late adverse effects such as pruritis and inflammation reported with calamine/diphenhydramine lotion, medicated shampoo, Olay Complete defense moisturizing lotion and Zineryt® topical solution. The skin irritation was likely a resultant oxidative stress action of soluble zinc, where a small fraction could be adequate to negate the skin homeostasis.[Figure: see text]Key messagesZinc is essentially a cofactor for skin collagen formation.Soluble zinc content as low as 10.5 µg/cm2 of skin irritates skin and negates burn wound healing.Skin irritation of commercial products relates to minute soluble zinc content availability.
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Queimaduras/tratamento farmacológico , Cloretos/uso terapêutico , Pele/patologia , Compostos de Zinco/uso terapêutico , Animais , Queimaduras/patologia , Queimaduras/veterinária , Cloretos/farmacologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos , Compostos de Zinco/farmacologiaRESUMO
A 61-year-old male presented with worsening dyspnoea and constitutional symptoms for few weeks followed by bloody diarrhoea and loss and fever. Physical exam revealed tachycardia, respiratory distress, and splenomegaly without lymphadenopathy. Work up showed pancytopenia, hypofibrinogenemia, acute kidney injury requiring haemodialysis, high ferritin level, positive IgG and IgM for EBV and positive soluble CD25. Chest CT scan showed bilateral pulmonary nodules. Lung biopsy showed intravascular pulmonary histiocytosis while bone marrow biopsy was negative for hemophagocytes. A diagnosis of hemophagocytic lymphohistiocytosis (HLH) was made based on fulfilling the diagnostic criteria and systemic steroids were initiated, which improved the patient's condition gradually with resolution of dyspnoea, AKI and pancytopenia. Repeat chest CT scan showed resolution of bilateral pulmonary nodules. The patient was transferred to a tertiary centre to receive HLH-specific therapy. We present a rare presentation of HLH with steroid-responsive bilateral pulmonary nodules and a rare histopathologic finding of pulmonary intravascular histiocytosis, which has never been described in HLH or the lung tree.
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BACKGROUND: Hymenolepis nana is among the most common intestinal parasitic infections causing a public health threat in poor communities in Sub-Saharan Africa. The present study was conducted to determine the prevalence of H. nana infections and associated risk factors among preschool children of displacement communities in Khartoum state, Sudan. METHODS: A cross-sectional survey was conducted in May 2013 in displacement camps, Khartoum state, Sudan. A simple random sample of preschool children from the displacement camps, aged between 1 and 5 years, were included. Information was collected by presenting a questionnaire and taking 500 fresh stool specimens which were examined microscopically for the presence of eggs, using direct saline and formal-ether concentration techniques. RESULTS: The prevalence of H. nana was determined to be 32.6% (163/500), 95% CI (28.5%-36.9%). Infections of H. nana were more prevalent among males than females, and this association was statistically significant (P < 0.001, OR = 2.125, 95% CI = 1.452-3.108). H. nana infections were significantly prevalent among the older age group (2.6-5.0 years) (P < 0.001, OR = 2.909, 95% CI = 1.914-4.420). Approximately 76.7% of infected preschool children had diarrhea and it was significantly associated with H. nana infection (P < 0.001, OR = 9.45, 95% CI = 6.10-14.64). None of the preschool children had access to a clean water supply. No significant association was found between use of latrines and infections of H. nana (P = 0.56, OR = 0.880, 95% CI = 0.73-1.763). CONCLUSIONS: There was a high prevalence rate of H. nana infection among preschool children of displacement camps in Khartoum state, Sudan. Being male, aged between 2.6 and 5.0 years, and having diarrhea were identified as important risk factors for H. nana infection. Measures including health education, environmental hygiene, water supply and treatment should be taken into account to reduce the high prevalence of H. nana.
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Himenolepíase/epidemiologia , Hymenolepis nana , Refugiados/estatística & dados numéricos , Animais , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pobreza , Prevalência , Fatores de Risco , Sudão/epidemiologia , Populações VulneráveisRESUMO
Rectocele is an abnormal protrusion of the anterior wall of the rectum into the vagina. When symptomatic, it will typically cause obstructed defecation. It is almost exclusively found in females with rare reports in males and never been described in the literature in children younger than 18 years of age so far. We are presenting 3 cases of rectocele with obstructed defecation in the pediatric population. These children presented with the complaints of constipation along with refractory straining. They were diagnosed by defecography. Two were treated surgically and one conservatively. Surgical intervention completely cured the problem with uneventful postoperative course. Further multicenter studies with the aid of radiologic studies on children with "hard to treat" constipation should be considered to better define that disorder in the pediatric age group. A more vigilant approach may have implications in the prevention of more severe rectal and uterovaginal prolapse in the future.
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Colectomia/métodos , Retocele/diagnóstico , Biópsia , Criança , Colonoscopia , Defecação , Diagnóstico Diferencial , Feminino , Seguimentos , Coprofagia Humana/diagnóstico , Humanos , Retocele/fisiopatologia , Retocele/cirurgiaRESUMO
Although previous studies have implicated lymphocytes in the gut microvascular and inflammatory responses to ischemia-reperfusion (I/R), the lymphocyte population and lymphocyte-derived products that mediate these responses have not been defined. Platelet and leukocyte adhesion was measured in intestinal postcapillary venules of wild-type (WT) mice and mice genetically deficient in either CD4+ T cells (CD4-/-), CD8+ T cells (CD8-/-), B cells (B cell-/-), or interferon-gamma (IFN-gamma-/-) subjected to 45 min of ischemia and 4 h of reperfusion. The I/R-induced platelet and leukocyte recruitment responses were also evaluated following adoptive transfer of WT splenocytes into CD4-/-, CD8-/-, B cell-/-, and IFN-gamma-/- mice. WT mice exposed to gut I/R exhibited significant increases in the adhesion of both platelets and leukocytes, compared with sham-WT mice. These blood cell adhesion responses to I/R were greatly attenuated in CD4-/-, CD8-/-, B cell-/-, and IFN-gamma-/- mice. Adoptive transfer of WT splenocytes restored the WT responses to I/R in all mutants except the B cell-/- mice. These findings implicate both T and B cells and lymphocyte-derived IFN-gamma as mediators of the proinflammatory and prothrombogenic phenotype assumed by intestinal microvessels after I/R.
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Interferon gama/metabolismo , Linfócitos/imunologia , Traumatismo por Reperfusão/imunologia , Vasculite/imunologia , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Plaquetas/citologia , Pressão Sanguínea , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Adesão Celular/imunologia , Frequência Cardíaca , Interferon gama/genética , Linfócitos/citologia , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Microcirculação/imunologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Vasculite/metabolismo , Vasculite/patologiaRESUMO
BACKGROUND/PURPOSE: Although ingestion of alkali-based and/or hypochlorite-based household cleaners as well as strong acids remains a major cause of esophageal wall injury, little is known about the mechanisms that underlie the injury response to these toxic agents. This study examined the roles of vascular dysfunction and inflammation to the esophageal injury response to different caustic substances in mice. METHODS: The esophageal responses to sodium hydroxide (10%, 5%, and 2.5%), potassium hydroxide (10%, 5%, and 2.5%), sodium hypochlorite (5.25%), and hydrochloric acid (10%, pH 2) were evaluated by intravital videomicroscopy and histopathology. Intravital microscopy was used to monitor changes in the diameter of arterioles and venules, the adhesion and movement of leukocytes in venules, and the time of cessation of arteriolar blood flow in mouse esophagus. The esophageal mucosa was exposed to caustic substances for 0 to 60 minutes before evaluation. RESULTS: The higher concentrations of sodium hydroxide and potassium hydroxide elicited rapid stasis in both arterioles and venules, which was accompanied by arteriolar constriction and thrombosis. An accumulation of adherent leukocytes in venules was not observed with any agent. Histopathological evaluation revealed marked cellular and interstitial edema in the mucosa with alkali, whereas hydrochloric acid and sodium hypochlorite decreased the thickness epithelial layer. CONCLUSION: These findings suggest that ischemia and thrombosis are dominant processes, whereas inflammation is less important in the pathogenesis of acute corrosive injury to the esophageal mucosa.
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Cáusticos/toxicidade , Esôfago/irrigação sanguínea , Esôfago/lesões , Ácido Clorídrico/toxicidade , Hidróxidos/toxicidade , Microcirculação/efeitos dos fármacos , Compostos de Potássio/toxicidade , Hidróxido de Sódio/toxicidade , Hipoclorito de Sódio/toxicidade , Animais , Esôfago/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Molybdenum cofactor and isolated sulphite oxidase deficiencies are two related rare autosomal recessive diseases characterized by severe neurological abnormalities, dislocated lens and mental retardation. Determination of three biochemical markers S-sulphocysteine (SSC), xanthine (XAN) and hypoxanthine (HXAN) in urine is essential for a definitive diagnosis and identification of the exact defect. We developed a rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of SSC, XAN and HXAN in urine. The analysis was carried out in the negative-ion selected-reaction monitoring mode. The turnaround time for the assay was 7 min. Linear calibration curves for the three biomarkers were obtained in the range of 12-480 micromol/L. The intra- and inter-day assay variations were <2.5%. Mean recoveries of SSC, XAN and HXAN added to urine at two significantly different concentrations were in the range 94.3-107.3%. At a normal SSC urine excretion value of 3.2 micromol/mmol creatinine, the signal-to-noise ratio was 337:1. This stable isotope dilution LC-MS/MS method is specific, rapid and simple, and provides definitive diagnosis for molybdenum cofactor and isolated sulphite oxidase deficiencies in very small volumes of urine. We have identified seven new cases of isolated sulphite oxidase deficiency from four Saudi families and one Sudanese family.
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Encefalopatias Metabólicas Congênitas/diagnóstico , Cisteína/análogos & derivados , Cisteína/urina , Hipoxantina/urina , Xantina/urina , Adulto , Encefalopatias Metabólicas Congênitas/urina , Criança , Pré-Escolar , Cromatografia Líquida , Coenzimas/deficiência , Humanos , Lactente , Recém-Nascido , Metaloproteínas/deficiência , Cofatores de Molibdênio , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/deficiência , Pteridinas , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
To assess the incidence of orthostatic hypotension [OH] in stroke patients undergoing rehabilitation and to determine clinical variables associated with it. Thirty patients with a first clinical stroke who underwent rehabilitation within one month of stroke onset were included in this study. They were 17 males and 13 females. Their age ranged from 49 to 68 years [mean +/- SD= 58.1 +/- 6.3]. Patients were subjected to full history taking, thorough clinical examination and investigations. Patients' blood pressure was measured in the supine position and on tilting at 90[0]. OH was defined as a drop in systolic blood pressure [SBP] of 20 mmHg or more. OH was present in 14 [46.7%] patients. Age was highly significantly associated [p<0.001] with OH and admission modified Barthel Index [MBI] score was significantly associated [p<0.05] with OH. There was a non-significant correlation with the site of stroke or the use of anti-hypertensives. OH was common in stroke patients undergoing inpatient rehabilitation especially in older patients who have a lower functional status
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Humanos , Masculino , Feminino , Reabilitação , Hipotensão OrtostáticaRESUMO
To detect the serum level of soluble E, P and L-selectins in systemic sclerosis [SSc] and Behcet's disease [BD] patients and compare them to normal healthy controls. Also, to determine their relation to clinical parameters of disease activity Serum samples from 15 SSc patients, 10 BD patients and 10 apparently healthy age and sex matched controls were examined with a sensitive linked immunosorbent assay. All patients were evaluated for the presence of gastrointestinal, pulmonary, renal, cardiac, Raynaud's phenomenon as well as joint or muscle involvement. Serum levels of E and P-selectins were highly significantly increased in SSc patients as compared to healthy controls. L-selectin was significantly higher in Raynaud's related scleroderma. Serum level of P-selectin was found to be higher in the diffuse form of SSc. There was no correlation of any selectin and pulmonary fibrosis. As regards BD, there was a highly significant increase in E-selectin and a significant increase in P-selectin in comparison with normal controls. Comparing SSc and BD as regards selectin; there was a significant increase of E and P-selectins in SSc. The values of E and P-selectins were found to be elevated in SSc and BD patients that might reflect their role in the pathogenesis of both diseases. The correlation of E, P and L-selectins with clinical parameters of SSc may help in evaluation of progression or remission of the disease. Further large long term study and serial measurements at different intervals of therapy are needed to correlate it with clinical deterioration or improvement and response to therapy
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Humanos , Masculino , Feminino , Síndrome de Behçet , Escleroderma Sistêmico , Selectina E , Selectina-P , Progressão da Doença , Selectina LRESUMO
Leflunomide and methotrexate have proven to be efficacious in reducing joint inflammation and joint destruction in clinical models of arthritis and in rheumatoid arthritis. The objective of this study was to evaluate the effects of both drugs as well as their combination therapy on the synovium and cartilage of adjuvant arthritis as a model of rheumatoid arthritis [RA] in humans. This study was carried out on forty animals stratified into 5 groups: normal, adjuvant arthritis [AA] control, AA who received leflunomide in a dose of 20 mg/kg orally, AA who received intraperitoneal methotrexate in a dose of 0.3 mg/kg twice weekly and AA who received both leflunomide and methotrexate of the same dose given in groups 3 and 4. All animals were sacrificed after 3 weeks; the right knee was dissected and examined with light microscopy. Oxidants markers [nitric oxide [NO] and malondialdhyde [MAD]] and antioxidants markers [glutathione [GSH], erythrocyte superoxide dismutase [SOD] and ceruloplasmin [CP]] were all measured. All the treatment modalities showed variable degrees of improvement of synovial and cartilage scoring in comparison to AA [the non-treated group]. The leflunomide treated group [group 3] showed the best improvement of synovial pathology, while the combined therapy group [group 5] showed the best improvement of cartilage pathology. The oxidative stress markers showed some changes with different modalities of treatment where, nitric oxide did not change significantly between all groups. Malondialdhyde [MAD] was significantly lower in the methotrexate [MTX] treated group as compared to AA controls. Also, superoxide dismutase [SOD] was significantly lower in the leflunomide treated group, MTX treated group as well as in the group who received combined therapy as compared to AA the controls. Glutathione [GSH] level was significantly decreased with combination therapy as compared to the leflunomide treated group. Serum ceruloplasmin [CP] showed a significant decrease in its level in the MTX treated group as compared to the AA controls. MTX treatment [group 4] was the best in controlling oxidative stress markers. Further study is needed to evaluate the duration and dose effect of each drug on synovium, cartilage and oxidative markers