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1.
Ther Adv Respir Dis ; 18: 17534666241231122, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357899

RESUMO

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an established minimally invasive method for the diagnosis of benign and malignant conditions. Continuous efforts are underway to improve the material adequacy of EBUS-TBNA, including the introduction of a new technique called EBUS-guided transbronchial nodal cryobiopsy (EBUS-TBNC). This method allows for the retrieval of larger and well-preserved histologic samples from the mediastinum. We present a case series of four patients who underwent combined EBUS-TBNA and EBUS-TBNC procedures in our centre. All procedures were performed under general anaesthesia using a convex probe EBUS scope (Pentax EB-1970UK). Two patients were diagnosed with malignancy and two with benign disorders (silicosis and tuberculosis). In the malignant cases, both EBUS-TBNA/cell block and cryobiopsy provided a diagnosis but cryobiopsy yielded more material for ancillary tests in one patient. However, in the benign cases, there was discordance between EBUS-TBNA/cell block and cryobiopsy. Only cryobiopsy detected granuloma in the patient with TB (tuberculosis), and in the patient with silicosis, TBNC provided a better overall histological evaluation, leading to a definitive diagnosis. No complications were observed. This case series supports the potential diagnostic value of combining EBUS-TBNA and EBUS-TBNC, particularly in benign mediastinal lesions (granulomatous diseases), and in cases requiring additional molecular tests in cancer diagnosis.


Exploring a new lymph node biopsy technique: case series from Sabah, MalaysiaWe explored a new technique for lung diagnosis called EBUS-guided transbronchial nodal cryobiopsy (EBUS-TBNC). This method helps get larger and well-preserved tissue samples from the chest area. In our study, we used this technique on four patients alongside the established method called EBUS-guided transbronchial needle aspiration (EBUS-TBNA). All procedures were done with the patient under general anesthesia using a specific type of scope. Two patients were found to have cancer, and two had non-cancerous conditions (silicosis and tuberculosis). In the cancer cases, both methods provided a diagnosis, but the cryobiopsy gave more material for additional tests in one patient. However, in non-cancer cases, there were differences between the two methods. Only the cryobiopsy detected granulomas in the tuberculosis patient, and in the silicosis patient, cryobiopsy gave a better overall tissue evaluation, leading to a clear diagnosis. No complications were seen in any of the cases. This study suggests that combining EBUS-TBNA and EBUS-TBNC can be valuable, especially for non-cancerous chest lesions (like granulomatous diseases) and when extra tests are needed for cancer diagnosis.


Assuntos
Neoplasias Pulmonares , Silicose , Tuberculose , Humanos , Malásia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Mediastino/diagnóstico por imagem , Mediastino/patologia , Broncoscopia/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Estudos Retrospectivos
2.
Trends Plant Sci ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38036390

RESUMO

Molecular motifs can explain information processing within single cells, while how assemblies of cells collectively achieve this remains less well understood. Plant fitness and survival depend upon robust and accurate decision-making in their decentralised multicellular organ systems. Mobile agents, including hormones, metabolites, and RNAs, have a central role in coordinating multicellular collective decision-making, yet mechanisms describing how cell-cell communication scales to organ-level transitions is poorly understood. Here, we explore how unified outputs may emerge in plant organs by distributed information processing across different scales and using different modalities. Mathematical and computational representations of these events are also explored toward understanding how these events take place and are leveraged to manipulate plant development in response to the environment.

3.
Cureus ; 15(9): e44676, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809275

RESUMO

Background The application of the Box-Jenkins autoregressive integrated moving average (ARIMA) model has been widely employed in predicting cases of infectious diseases. It has shown a positive impact on public health early warning surveillance due to its capability in producing reliable forecasting values. This study aimed to develop a prediction model for new tuberculosis (TB) cases using time-series data from January 2013 to December 2018 in Malaysia and to forecast monthly new TB cases for 2019. Materials and methods The ARIMA model was executed using data gathered between January 2013 and December 2018 in Malaysia. Subsequently, the well-fitted model was employed to make projections for new TB cases in the year 2019. To assess the efficacy of the model, two key metrics were utilized: the mean absolute percentage error (MAPE) and stationary R-squared. Furthermore, the sufficiency of the model was validated via the Ljung-Box test. Results The results of this study revealed that the ARIMA (2,1,1)(0,1,0)12 model proved to be the most suitable choice, exhibiting the lowest MAPE value of 6.762. The new TB cases showed a clear seasonality with two peaks occurring in March and December. The proportion of variance explained by the model was 55.8% with a p-value (Ljung-Box test) of 0.356. Conclusions The application of the ARIMA model has developed a simple, precise, and low-cost forecasting model that provides a warning six months in advance for monitoring the TB epidemic in Malaysia, which exhibits a seasonal pattern.

4.
Asia Pac J Public Health ; 35(2-3): 162-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36872616

RESUMO

This single-center study aimed to explore the factors associated with coronavirus disease (COVID-19) transmission in a hospital. All laboratory-confirmed COVID-19 cases among health care workers (HCWs) in a tertiary hospital in Malaysia were analyzed cross-sectionally from January 25, 2020, to September 10, 2021. A total of 897 HCWs in the hospital had laboratory-confirmed COVID-19 infection during the study period. Around 37.4% of HCWs were suspected to acquire COVID-19 infection from the hospital workplace. Factors associated with lower odds of workplace COVID-19 transmission were being females, ≥30 years old, fully vaccinated, and working as clinical support staff. Involvement in COVID-19 patient care was significantly associated with higher odds (adjusted odds ratio = 3.53) of workplace COVID-19 transmission as compared with non-workplace transmission. Most HCWs in the tertiary hospital acquired COVID-19 infection from non-workplace settings. During a pandemic, it is important to communicate with HCWs about the risk of both workplace and non-workplace COVID-19 transmission and to implement measures to reduce both workplace and non-workplace COVID-19 transmission.


Assuntos
COVID-19 , Infecção Hospitalar , Feminino , Humanos , Adulto , Masculino , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , SARS-CoV-2 , Malásia/epidemiologia , Pessoal de Saúde , Centros de Atenção Terciária
6.
Front Cardiovasc Med ; 10: 1295602, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259311

RESUMO

A 14-year-old male with no significant medical history presented with intermittent palpitations for 2-3 months that occurred at rest and were associated with light-headedness. Electrocardiogram in clinic showed sinus arrhythmia with early repolarization and no ischemic changes. The echocardiogram showed normal cardiac structure and function, however, there was a concern for possible anomalous origin of the left coronary artery. Contrast-enhanced CT coronary artery angiogram confirmed a single coronary origin from the right coronary sinus. The single main coronary artery gave rise to the right coronary artery (RCA) and the left coronary artery (LCA). The LCA demonstrated a trans-septal course before it gave rise to the left anterior descending and left circumflex artery. There were intraarterial and intramural portions of the LCA, and the sinoatrial node artery arose from the LCA. The RCA demonstrated a normal course to the right atrioventricular groove, and the posterior descending artery arose from the RCA. Treadmill exercise stress test showed excellent functional capacity without exercise-induced chest pain or ischemic ECG changes. Invasive coronary angiography ruled out luminal narrowing or dynamic compression. Given the absence of physiologic or anatomic evidence of coronary flow restriction, no intervention was pursued and the palpitations were deemed to be likely unrelated to the coronary anomaly and eventually subsided spontaneously on 6 month follow-up.

7.
Epilepsy Res ; 187: 107033, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36274423

RESUMO

OBJECTIVES: Prevalence of seizures in brain tumors vary substantially between studies even with similar histopathological types. We aimed to identify the seizure prevalence of the commonest types of brain tumors. METHODS: Systematic computerized search of PubMed, Embase, and Web of Science were performed. The meta-analysis of pooled prevalence and 95 % confidence interval (CI) for tumor-related seizures were calculated by using a random effect model. Based on the 2014 epilepsy definition, a mean seizure prevalence of 60 % is used to indicate high seizure prevalence in this study. RESULTS: 74 studies that reported seizure prevalence with 23,116 patients were included in this meta-analysis. These tumors has higher seizure incidence rate (at least 60 %) with pooled prevalence of 63 % for adult with low-grade astrocytoma (95 % CI: 57-68 %), 65 % for oligodendroglioma (95% CI: 57-72 %), 72 % for oligoastrocytoma (95 % CI: 67-77 %), 81 % for ganglioglioma (95 % CI: 66-97 %) and 94 % for DNET (94 % CI: 83-100 %). CONCLUSION: This study highlights the type of brain tumors that carry a high seizure prevalence. Screening for subtle seizures and early management of seizures may be beneficial in patients with low-grade astrocytoma (adult), oligodendroglioma, oligoastrocytoma, ganglioglioma or DNET brain tumor.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Ganglioglioma , Oligodendroglioma , Adulto , Humanos , Oligodendroglioma/complicações , Prevalência , Convulsões/etiologia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/patologia , Astrocitoma/complicações , Astrocitoma/epidemiologia
8.
BMC Infect Dis ; 21(1): 1238, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34886794

RESUMO

BACKGROUND: Hospitals are vulnerable to COVID-19 outbreaks. Intrahospital transmission of the disease is a threat to the healthcare systems as it increases morbidity and mortality among patients. It is imperative to deepen our understanding of transmission events in hospital-associated cases of COVID-19 for timely implementation of infection prevention and control measures in the hospital in avoiding future outbreaks. We examined the use of epidemiological case investigation combined with whole genome sequencing of cases to investigate and manage a hospital-associated cluster of COVID-19 cases. METHODS: An epidemiological investigation was conducted in a University Hospital in Malaysia from 23 March to 22 April 2020. Contact tracing, risk assessment, testing, symptom surveillance, and outbreak management were conducted following the diagnosis of a healthcare worker with SARS-CoV-2 by real-time PCR. These findings were complemented by whole genome sequencing analysis of a subset of positive cases. RESULTS: The index case was symptomatic but did not fulfill the initial epidemiological criteria for routine screening. Contact tracing suggested epidemiological linkages of 38 cases with COVID-19. Phylogenetic analysis excluded four of these cases. This cluster included 34 cases comprising ten healthcare worker-cases, nine patient-cases, and 15 community-cases. The epidemic curve demonstrated initial intrahospital transmission that propagated into the community. The estimated median incubation period was 4.7 days (95% CI: 3.5-6.4), and the serial interval was 5.3 days (95% CI: 4.3-6.5). CONCLUSION: The study demonstrated the contribution of integrating epidemiological investigation and whole genome sequencing in understanding disease transmission in the hospital setting. Contact tracing, risk assessment, testing, and symptom surveillance remain imperative in resource-limited settings to identify and isolate cases, thereby controlling COVID-19 outbreaks. The use of whole genome sequencing complements field investigation findings in clarifying transmission networks. The safety of a hospital population during this COVID-19 pandemic may be secured with a multidisciplinary approach, good infection control measures, effective preparedness and response plan, and individual-level compliance among the hospital population.


Assuntos
COVID-19 , Surtos de Doenças , Hospitais Universitários , Humanos , Malásia/epidemiologia , Pandemias , Filogenia , SARS-CoV-2
11.
J Relig Health ; 60(6): 4579-4599, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34514548

RESUMO

The COVID-19 pandemic has been a global phenomenon defined by uncertainty, fear and grief which has resulted in record high levels of stress and anxiety in the first half of 2020. It also led to an increased interest in the study of the role of belief, religion, and spirituality as responses to coping with and responding to the pandemic throughout different societal domains. This study explores the impact of anxiety and stress caused by the pandemic on Muslim academics' subjective well-being. It also explores correlations between coping and spirituality by assessing Muslim academics' coping strategies in overcoming stress and anxiety. To this end, this study sampled 480 Muslim academics ages 25-60 years residing in Muslim countries. The findings show a negative yet significant correlation between anxiety and well-being while also showing a positive and significant correlation between coping strategies and subjective well-being. The research also points to the role of coping strategies in reducing anxiety and stress, the resulting improvements in well-being for Muslim academics, and the mediating effect of coping strategies between anxiety, stress, and well-being for Muslim academics.


Assuntos
COVID-19 , Pandemias , Adaptação Psicológica , Adulto , Ansiedade/epidemiologia , Humanos , Islamismo , Pessoa de Meia-Idade , SARS-CoV-2
12.
Trop Life Sci Res ; 32(1): 107-117, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33936554

RESUMO

Mitragyna speciosa (Korth.) Havil. or locally known as ketum/daun sebiak/biak-biak belongs to Rubiaceae family and generally occurs in secondary forest or disturbed areas in tropical and subtropical region. This research enumerated the characterisation of Mitragyna speciosa leaf anatomy and micromorphology features which is still not well documented. This medium to large sized tree species characterised with opposite arrangement, ovate-acuminate leaf and with 12-17 pairs of veins. Transverse sections of petioles showed that this species has petiole outlines with slightly convex at the middle of the adaxial part and 'U'-shaped on abaxial side. Results also showed that this species has paracytic and hypostomatic stomata, combination of non-glandular (majority) and glandular trichomes (minority), with observation on the secretory cells present in petiole and midrib parenchyma cells. Cuticle on the abaxial and adaxial epidermal surfaces showed the presence granule and wax films with periclinal and anticlinal walls can be differentiated clearly. The results obtained in this study can be used to providing additional systematics information of Mitragyna speciosa with the documentation of the leaf anatomy and micromorphology characters.

13.
Chemosphere ; 280: 130730, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33964756

RESUMO

Phosphate functionalized graphene oxide (PGO) was successfully prepared by Arbuzov reaction and employed for adsorption of resorcinol from an aqueous phase. The phosphate functional groups were successfully incorporated onto the PGO surface by the formation of P-C bonds as identified by the analysis of FTIR and XPS spectra. The evaluation of adsorption capacity of resorcinol onto PGO exhibited significant improvement of resorcinol removal, achieving an adsorption capacity of 50.25 mg/g in the pH range of 4-7 which was 15 times higher than pristine graphene oxide. The addition of 2.4 M and 5 M NaCl in the adsorption system significantly increased the adsorption capacity towards resorcinol from 50.25 mg/g to 82.10 mg/g and 128.10 mg/g, respectively. Based on kinetics and adsorption isotherm studies, Pseudo-First-Order and Langmuir model are the best model to describe the adsorption process indicating that the adsorption is dominantly controlled by physisorption. The thermodynamic analysis suggested that the adsorption process was the favorable, spontaneous, and endothermic process. Besides, the interplay of hydrogen bonding and π-π interactions is proposed to be the governing physisorption mechanism. The outstanding reusability and better adsorption performance make PGO a promising adsorbent for environmental remediation of resorcinol.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Ligação de Hidrogênio , Cinética , Fosfatos , Resorcinóis , Poluentes Químicos da Água/análise
14.
PLoS One ; 16(4): e0249394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852588

RESUMO

INTRODUCTION: The reporting of Coronavirus Disease 19 (COVID-19) mortality among healthcare workers highlights their vulnerability in managing the COVID-19 pandemic. Some low- and middle-income countries have highlighted the challenges with COVID-19 testing, such as inadequate capacity, untrained laboratory personnel, and inadequate funding. This article describes the components and implementation of a healthcare worker surveillance programme in a designated COVID-19 teaching hospital in Malaysia. In addition, the distribution and characteristics of healthcare workers placed under surveillance are described. MATERIAL AND METHODS: A COVID-19 healthcare worker surveillance programme was implemented in University Malaya Medical Centre. The programme involved four teams: contact tracing, risk assessment, surveillance and outbreak investigation. Daily symptom surveillance was conducted over fourteen days for healthcare workers who were assessed to have low-, moderate- and high-risk of contracting COVID-19. A cross-sectional analysis was conducted for data collected over 24 weeks, from the 6th of March 2020 to the 20th of August 2020. RESULTS: A total of 1,174 healthcare workers were placed under surveillance. The majority were females (71.6%), aged between 25 and 34 years old (64.7%), were nursing staff (46.9%) and had no comorbidities (88.8%). A total of 70.9% were categorised as low-risk, 25.7% were moderate-risk, and 3.4% were at high risk of contracting COVID-19. One-third (35.2%) were symptomatic, with the sore throat (23.6%), cough (19.8%) and fever (5.0%) being the most commonly reported symptoms. A total of 17 healthcare workers tested positive for COVID-19, with a prevalence of 0.3% among all the healthcare workers. Risk category and presence of symptoms were associated with a positive COVID-19 test (p<0.001). Fever (p<0.001), cough (p = 0.003), shortness of breath (p = 0.015) and sore throat (p = 0.002) were associated with case positivity. CONCLUSION: COVID-19 symptom surveillance and risk-based assessment have merits to be included in a healthcare worker surveillance programme to safeguard the health of the workforce.


Assuntos
Teste para COVID-19/métodos , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Adulto , COVID-19/diagnóstico , Teste para COVID-19/tendências , Comorbidade , Busca de Comunicante/métodos , Estudos Transversais , Monitoramento Epidemiológico , Feminino , Pessoal de Saúde , Hospitais de Ensino , Humanos , Malásia/epidemiologia , Masculino , Pandemias , SARS-CoV-2/isolamento & purificação
15.
Zootaxa ; 4802(3): zootaxa.4802.3.7, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-33056047

RESUMO

The first representative of the genus Cerapus in Malaysian waters, Cerapus bumbumiensis sp. nov. is described from specimens sampled from Pulau Bum Bum, Sabah (east Malaysia). The main identifying characteristics of this new amphipod species are: pereonites 1, 2 with constriction; male gnathopod 2 carpochelate, carpus large with long defining posterior tooth and well-developed anterodistal tooth; pereopod 6 coxa with fine hair/fringe setae ventrally; and telson with deep cleft. An updated identification key for the 23 known species in the genus is also presented.


Assuntos
Anfípodes , Animais , Malásia , Masculino
16.
Trop Med Infect Dis ; 5(2)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370071

RESUMO

Bacillus thuringiensis israelensis (Bti) is an effective biological insecticide for killing mosquito larvae. However, choosing the suitable application method for larviciding is critical in increasing its effectiveness. Therefore, this study aimed to determine the effectiveness of Bti (VectoBac®) WG using various applications at high-rise buildings. Three different applications of Bti treatment were applied at three high-rise buildings in Bandar Saujana Putra. The ULV machine is used for Pangsapuri Impian, a mist blower for Pangsapuri Seri Saujana and a pressured sprayer for BSP 21. BSP Skypark does not undergo treatment and acts as a control. The efficacy of Bti treatment was measured by analyzing the ovitrap surveillance data collected (POI and MLT) for pre and post-treatment. Post-treatment ovitrap surveillance indicates that the Aedes sp. mosquito density was lower than the density at the time of pre-treatment surveillance. Overall, the Aedes albopictus species in both an indoor and outdoor environment setting had shown a reduction. The highest Aedes sp. density reduction is seen through the use of mist blowers in outdoor settings for Aedes albopictus, (%POI reduction = 87.4%; %MLT reduction = 93.8%). The mist blower yielded results that is significantly higher compared to other larviciding applications; the order from greatest to the least was mist blower > pressured sprayer > ULV. It can be concluded that each application produces different degrees of effectiveness in reducing the Aedes sp. density in different environmental settings.

17.
Chemosphere ; 256: 127081, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32447112

RESUMO

Discharging coloring products in water bodies has degraded water quality irreversibly over the past several decades. Order mesoporous carbon (OMC) was modified by embedding neodymium(III) chloride on the surface of OMC to enhance the adsorptive removal towards these contaminants. This paper represents an artificial neural network (ANN) based approach for modeling the adsorption process of sunset yellow onto neodymium modified OMC (OMC-Nd) in batch adsorption experiments. Neodymium modified OMC was characterized using N2 adsorption-desorption isotherm, TEM micrographs, FT-IR and XPS spectra analysis techniques. 2.5 wt% Nd loaded OMC was selected as the final adsorbent for further experiments because OMC-2.5Nd showed highest removal efficiency of 93%. The ANN model was trained and validated with the adsorption experiments data where initial concentration, reaction time, and adsorbent dosage were selected as the variables for the batch study, whereas the removal efficiency was considered as the output. The ANN model was first developed using a three-layer back propagation network with the optimum structure of 3-6-1. The model employed tangent sigmoid transfer function as input in the hidden layer whereas a linear transfer function was used in the output layer. The comparison between modeled data and experimental data provided high degree of correlation (R2 = 0.9832) which indicated the applicability of ANN model for describing the adsorption process with reasonable accuracy.


Assuntos
Compostos Azo/química , Modelos Químicos , Redes Neurais de Computação , Adsorção , Carbono/química , Concentração de Íons de Hidrogênio , Cinética , Neodímio , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Environ Sci Pollut Res Int ; 27(19): 23616-23630, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32291646

RESUMO

Functionalized ordered mesoporous carbon (MOMC-NP) was synthesized by chemical modification using HNO3 and H3PO4 to enhance Pb(II) adsorption. The phosphate functional group represented by P-O-C bonding onto the surface of OMC was verified by FT-IR and XPS. Batch adsorption experiments revealed the improvement of adsorption capacity by 39 times over the virgin OMC. Moreover, the Pb(II) adsorption results provided excellent fits to Langmuir model and pseudo-second-order kinetic model. The adsorption mechanism of Pb(II) onto MOMC-NP revealed the formation of metal complexes with carboxyl, hydroxyl, and phosphate groups through ion exchange reactions and hydrogen bondings. The calculated activation energy was 22.09 kJ/mol, suggesting that Pb(II) adsorption was a chemisorption. At pH>pHpzc, the main Pb(II) existing species of Pb(II) and Pb(OH)+ combine with the carboxyl, hydroxyl, and phosphate functional groups via electrostatic interactions and hydrogen bonding. All these findings demonstrated that MOMC-NP could be a useful and potential adsorbent for adsorptive removal of Pb(II). Graphical abstract.


Assuntos
Carbono , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
19.
Chemosphere ; 248: 126078, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32041070

RESUMO

The surface properties of graphene oxide (GO) have been identified as the key effects on the adsorption of Pb(II) from aqueous solutions in this study. This study reveals the effect of the surface reactivity of GO via Carbon Disulfide (CS2) functionalization for Pb(II) adsorption. After successfully preparing CS2 functionalized GO (GOCS), the specific techniques were applied to investigate Pb(II) adsorption onto GOCS. Results indicated that the new sulfur-containing functional groups incorporated onto GOCS significantly enhanced Pb(II) adsorption capacity on GOCS than that of GO, achieving an improvement of 31% in maximum adsorption capacity increasing from 292.8 to 383.4 mg g-1. The equilibrium adsorption capacity for GOCS was 280.2 mg g-1 having an improvement of 83.2% over that of 152.97 mg g-1 for GO at the same initial concentration of 150 mg L-1 under the optimal pH of 5.7. Moreover, the results of adsorption experiments showed an excellent fit to the Langmuir and Pseudo-Second-Order models indicating the monolayer and chemical adsorption, respectively. The mechanism for Pb(II) adsorption on GOCS was proposed as the coordination, electrostatic interactions, cation-pi interactions, and Lewis acid-base interactions. The regeneration study showed that GOCS had an appreciable reusability for Pb(II) adsorption with the adsorption capacity of 208.92 mg g-1 after five regeneration cycles. In summary, GOCS has been proved to be a novel, useful, and potentially economic adsorbent for the high-efficiency removal of Pb(II) from aqueous solutions.


Assuntos
Dissulfeto de Carbono/química , Grafite/química , Chumbo/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Cinética , Propriedades de Superfície
20.
Front Oncol ; 10: 592130, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33738242

RESUMO

BACKGROUND: Mitochondria are highly dynamic organelles which remain in a continuous state of fission/ fusion dynamics to meet the metabolic needs of a cell. However, this fission/fusion dynamism has been reported to be dysregulated in most cancers. Such enhanced mitochondrial fission is demonstrated to be positively regulated by some activating oncogenic mutations; such as those of KRAS (Kristen rat sarcoma viral oncogene homologue) or BRAF (B- rapidly accelerated fibrosarcoma), thereby increasing tumor progression/ chemotherapeutic resistance and metabolic deregulation. However, the underlying mechanism(s) are still not clear, thus highlighting the need to further explore possible mechanism(s) of intervention. We sought to investigate how BRAFV600E driven CRC (colorectal cancer) progression is linked to mitochondrial fission/fusion dynamics and whether this window could be exploited to target CRC progression. METHODS: Western blotting was employed to study the differences in expression levels of key proteins regulating mitochondrial dynamics, which was further confirmed by confocal microscopy imaging of mitochondria in endogenously expressing BRAFWT and BRAFV600E CRC cells. Proliferation assays, soft agar clonogenic assays, glucose uptake/lactate production, ATP/ NADPH measurement assays were employed to study the extent of carcinogenesis and metabolic reprograming in BRAFV600E CRC cells. Genetic knockdown (shRNA/ siRNA) and/or pharmacologic inhibition of Dynamin related protein1/Pyruvate dehydrogenase kinase1 (DRP1/PDK1) and/or BRAFV600E were employed to study the involvement and possible mechanism of these proteins in BRAFV600E driven CRC. Statistical analyses were carried out using Graph Pad Prism v 5.0, data was analyzed by unpaired t-test and two-way ANOVA with appropriate post hoc tests. RESULTS: Our results demonstrate that BRAFV600E CRC cells have higher protein levels of mitochondrial fission factor- DRP1/pDRP1S616 leading to a more fragmented mitochondrial state compared to those harboring BRAFWT . This fragmented mitochondrial state was found to confer glycolytic phenotype, clonogenic potential and metastatic advantage to cells harboring BRAFV600E . Interestingly, such fragmented mitochondrial state seemed positively regulated by mitochondrial PDK1 as observed through pharmacologic as well as genetic inhibition of PDK1. CONCLUSION: In conclusion, our data suggest that BRAFV600E driven colorectal cancers have fragmented mitochondria which confers glycolytic phenotype and growth advantage to these tumors, and such phenotype is dependent at least in part on PDK1- thus highlighting a potential therapeutic target.

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