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1.
Toxics ; 11(11)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37999533

RESUMEN

Microplastics (MPs) are emerging environmental pollutants worldwide, posing potential health risks. Moreover, MPs may act as vectors for other contaminants and affect their fate, transport, and deposition in the environment. Therefore, efficient and economical techniques are needed for the removal of contemporary MPs and contaminants from the environment. The present research study investigated the sorption of phosphorus (P) and ammonium (NH4+) onto date palm waste-derived biochar (BC) from an aqueous solution in the presence of polyamide (PA) and polyethylene (PE) MPs. The BC was prepared at 600 °C, characterized for physio-chemical properties, and applied for P and NH4+ removal via isotherm and kinetic sorption trials. The results of the sorption trials demonstrated the highest removal of NH4+ and P was obtained at neutral pH 7. The highest P sorption (93.23 mg g-1) by BC was recorded in the presence of PA, while the highest NH4+ sorption (103.76 mg g-1) was found with co-occurring PE in an aqueous solution. Sorption isotherm and kinetics models revealed that P and NH4+ removal by MP-amended BC followed chemisorption, electrostatic interaction, precipitation, diffusion, and ion exchange mechanisms. Overall, co-existing PA enhanced the removal of P and NH4+ by 66% and 7.7%, respectively, while co-existing PE increased the removal of P and NH4+ by 55% and 30%, respectively, through the tested BC. Our findings suggested that converting date palm waste into BC could be used as a competent and economical approach to removing P and NH4+ from contaminated water. Furthermore, microplastics such as PE and PA could assist in the removal of P and NH4+ from contaminated water using BC.

2.
Eur Rev Med Pharmacol Sci ; 25(22): 7162-7184, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34859882

RESUMEN

The last two decades have witnessed the emergence of three deadly coronaviruses (CoVs) in humans: severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). There are still no reliable and efficient therapeutics to manage the devastating consequences of these CoVs. Of these, SARS-CoV-2, the cause of the currently ongoing coronavirus disease 2019 (COVID-19) pandemic, has posed great global health concerns. The COVID-19 pandemic has resulted in an unprecedented crisis with devastating socio-economic and health impacts worldwide. This highlights the fact that CoVs continue to evolve and have the genetic flexibility to become highly pathogenic in humans and other mammals. SARS-CoV-2 carries a high genetic homology to the previously identified CoV (SARS-CoV), and the immunological and pathogenic characteristics of SARS-CoV-2, SARS-CoV, and MERS contain key similarities and differences that can guide therapy and management. This review presents salient and updated information on comparative pathology, molecular pathogenicity, immunological features, and genetic characterization of SARS-CoV, MERS-CoV, and SARS-CoV-2; this can help in the design of more effective vaccines and therapeutics for countering these pathogenic CoVs.


Asunto(s)
COVID-19/virología , Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Patología Molecular/métodos , SARS-CoV-2/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Animales , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/transmisión , Femenino , Salud Global/economía , Humanos , Masculino , Mamíferos , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Coronavirus del Síndrome Respiratorio de Oriente Medio/patogenicidad , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/patogenicidad , SARS-CoV-2/inmunología , SARS-CoV-2/patogenicidad , Virulencia
3.
Eur Rev Med Pharmacol Sci ; 25(19): 5947-5964, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34661254

RESUMEN

The recent Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) outbreak has resulted in coronavirus disease 2019 (COVID-19) pandemic worldwide, affecting millions of lives. Although vaccines are presently made available, and vaccination drive is in progress to immunize a larger population; still the risk of SARS-CoV-2 infection and related mortality is persistent amid threats of the third wave of the ongoing pandemic. In the scenario of unavailability of robust and efficient treatment modalities, it becomes essential to understand the mechanism of action of the virus and deeply study the molecular mechanisms (both at the virus level and the host level) underlying the infection processes. Recent studies have shown that coronaviruses (CoVs) cause-specific epigenetic changes in the host cells to create a conducive microenvironment for replicating, assembling, and spreading. Epigenetic mechanisms can contribute to various aspects of the SARS-CoV-2 multiplication cycle, like expressing cytokine genes, viral receptor ACE2, and implicating different histone modifications. For SARS-CoV-2 infection, viral proteins are physically associated with various host proteins resulting in numerous interactions between epigenetic enzymes (i.e., histone deacetylases, bromodomain-containing proteins). The involvement of epigenetic mechanisms in the virus life cycle and the host immune responses to control infection result in epigenetic factors recognized as emerging prognostic COVID-19 biomarkers and epigenetic modulators as robust therapeutic targets to curb COVID-19. Therefore, this narrative review aimed to summarize and discuss the various epigenetic mechanisms that control gene expression and how these mechanisms are altered in the host cells during coronavirus infection. We also discuss the opportunities to exploit these epigenetic changes as therapeutic targets for SARS-CoV-2 infection. Epigenetic alterations and regulation play a pivotal role at various levels of coronavirus infection: entry, replication/transcription, and the process of maturation of viral proteins. Coronaviruses modulate the host epigenome to escape the host immune mechanisms. Therefore, host epigenetic alterations induced by CoVs can be considered to develop targeted therapies for COVID-19.


Asunto(s)
COVID-19/genética , COVID-19/terapia , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/terapia , Epigénesis Genética/genética , Epigenoma , Interacciones Huésped-Patógeno , Humanos
4.
Molecules ; 26(15)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34361826

RESUMEN

Vertical translocation/leaching of sulfamethoxazole (SMZ) through manure-amended sandy loam soil and significance of biochar application on SMZ retention were investigated in this study. Soil was filled in columns and amended with manure spiked with 13.75 mg kg-1 (S1), 27.5 mg kg-1 (S2), and 55 mg kg-1 (S3) of SMZ. Jujube (Ziziphus jujube L.) wood waste was transformed into biochar and mixed with S3 at 0.5% (S3-B1), 1.0% (S3-B2), and 2.0% (S3-B3) ratio. Cumulative SMZ leaching was lowest at pH 3.0, which increased by 16% and 34% at pH 5.0 and 7.0, respectively. A quicker release and translocation of SMZ from manure occurred during the initial 40 h, which gradually reduced over time. Intraparticle diffusion and Elovich kinetic models were the best fitted to leaching data. S3 exhibited the highest release and vertical translocation of SMZ, followed by S2, and S1; however, SMZ leaching was reduced by more than twofold in S3-B3. At pH 3.0, 2.0% biochar resulted in 99% reduction in SMZ leaching within 72 h, while 1.0% and 0.5% biochar applications reduced SMZ leaching to 99% within 120 and 144 h, respectively, in S3. The higher SMZ retention onto biochar could be due to electrostatic interactions, H-bonding, and π-π electron donor acceptor interactions.


Asunto(s)
Carbón Orgánico/química , Estiércol/análisis , Arena/química , Contaminantes del Suelo/metabolismo , Sulfametoxazol/metabolismo , Madera/química , Riego Agrícola , Contaminantes del Suelo/análisis , Sulfametoxazol/análisis
5.
Sci Rep ; 10(1): 16125, 2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32999378

RESUMEN

Novel carbon nanodots (nCD-DBC) and nano zero-valent iron composites (nZVI-DBC) were synthesized using date palm waste-derived biochar (DBC). The synthesized materials were analyzed for chemical and structural composition by using FTIR, SEM, XRD, and TGA, and evaluated for their methylthioninium chloride dye (MB) removal efficiency from contaminated aqueous solutions. pH 7.0 was found optimum for the highest MB removal in sorption batch studies. Kinetics sorption of MB onto the sorbents was best described by pseudo-second-order (R2 = 0.93-0.99) and Elovich models (R2 = 0.86-0.97) implying that sorption was being controlled by chemisorption. Langmuir model predicted maximum sorption capacities for nCD-DBC, nZVI-DBC, and DBC were 1558.66, 1182.90, and 851.67 mg g-1, respectively, which correlated with the results of kinetics sorption. Likewise, nCD-DBC yielded the highest partition coefficient (7067 mL g-1), followed by nZVI-DBC (1460 mL g-1), and DBC (930 mL g-1). Post-sorption XRD, FTIR, and SEM analyses depicted the binding of MB onto the sorbents. It was suggested that electrostatic interactions, π-π electron donor-accepter interactions, degradation, and diffusion were responsible for MB removal by the synthesized materials. Therefore, the nCD-DBC, nZVI-DBC, and DBC can potentially be used for scavenging MB dye from contaminated aqueous solutions.

6.
PLoS One ; 15(7): e0232811, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32614852

RESUMEN

In the present work, the olive mill solid waste (OMSW)-derived biochar (BC) was produced at various pyrolytic temperatures (300-700°C) and characterized to investigate its potential negative versus positive application effects on pH, electrical conductivity (EC), and nutrients (P, K, Na, Ca, Mg, Fe, Mn, Zn, and Cu) availability in a calcareous loamy sand soil. Therefore, a greenhouse pot experiment with maize (Zea mays L.) was conducted using treatments consisting of a control (CK), inorganic fertilizer of NPK (INF), and 1% and 3% (w/w) of OMSW-derived BCs. The results showed that BC yield, volatile matter, functional groups, and zeta potential decreased with pyrolytic temperature, whereas BC pH, EC, and its contents of ash and fixed carbon increased with pyrolytic temperature. The changes in the BC properties with increasing pyrolytic temperatures reflected on soil pH, EC and the performance of soil nutrients availability. The BC application, especially with increasing pyrolytic temperature and/or application rate, significantly increased soil pH, EC, NH4OAc-extractable K, Na, Ca, and Mg, and ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA)-extractable Fe and Zn, while AB-DTPA-extractable Mn decreased. The application of 1% and 3% BC, respectively, increased the NH4OAc-extractable K by 2.5 and 5.2-fold for BC300, by 3.2 and 8.0-fold for BC500, and by 3.3 and 8.9-fold for BC700 compared with that of untreated soil. The results also showed significant increase in shoot content of K, Na, and Zn, while there was significant decrease in shoot content of P, Ca, Mg, and Mn. Furthermore, no significant effects were observed for maize growth as a result of BC addition. In conclusion, OMSW-derived BC can potentially have positive effects on the enhancement of soil K availability and its plant content but it reduced shoot nutrients, especially for P, Ca, Mg, and Mn; therefore, application of OMSW-derived BC to calcareous soil might be restricted.


Asunto(s)
Carbón Orgánico/farmacología , Nutrientes/análisis , Olea/química , Arena/química , Suelo/química , Carbón Orgánico/química , Concentración de Iones de Hidrógeno , Minerales/metabolismo , Nutrientes/metabolismo , Factores de Tiempo , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo
7.
Acta Neurochir Suppl ; 124: 69-74, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28120055

RESUMEN

Minimally invasive spine surgery (MISS), including percutaneous pedicle-screw fixation (PPSF), mini-open transforaminal lumbar interbody fusion (m-open TLIF), vertebroplasty, and stentoplasty, allows the preservation of neurological function and the restoration of spine stability, while reducing associated risks and complications. This study aimed to analyze the safety and efficacy of MISS in elderly patients suffering from degenerative or traumatic thoracolumbar diseases. Forty-five patients (28 females), with a mean age of 73 years (range 65-89), suffering from osteoporotic vertebral fractures (24), degenerative spondylolisthesis (15), and lumbar canal stenosis with instability and/or de novo scoliosis (6) were included.Twenty-one patients underwent PPSF and m-open TLIF. The remaining patients received PPSF without interbody fusion, and in six of these fenestrated screws were used for vertebral body cement augmentation.Functional evaluation was obtained with a visual analog scale (VAS) and the Oswestry Disability Index (ODI) pre- and postoperatively. Preoperative imaging included X-rays, computed tomography (CT), and magnetic resonance imaging (MRI). Patients were followed-up with X-rays, and a CT scan was also obtained at the last follow-up. Follow-up ranged from 6 to 59 months (mean 28 months). Follow-up CT scan documented intersomatic fusion in only 14 % of patients treated with m-open TLIF. Despite the high incidence of non-union, mean VAS and ODI scores showed a significant improvement, with a reduction of mean VAS from 9 to 4 and a reduction of mean ODI from 76.33 to 38.15 %. Only three patients developed postoperative complications. No patients showed neurological deficits.Minimally invasive spine surgery for degenerative and traumatic spinal diseases is a safe and effective treatment also in elderly patients.


Asunto(s)
Vértebras Lumbares/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Procedimientos Neuroquirúrgicos/métodos , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/cirugía , Estenosis Espinal/cirugía , Espondilolistesis/cirugía , Vértebras Torácicas/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas/métodos , Humanos , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/diagnóstico por imagen , Tornillos Pediculares , Estudios Prospectivos , Radiografía , Escoliosis/diagnóstico por imagen , Escoliosis/etiología , Escoliosis/cirugía , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fusión Vertebral/métodos , Estenosis Espinal/complicaciones , Estenosis Espinal/diagnóstico por imagen , Espondilolistesis/complicaciones , Espondilolistesis/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Resultado del Tratamiento , Vertebroplastia/métodos
8.
Saudi J Kidney Dis Transpl ; 20(2): 260-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19237815

RESUMEN

In most developing countries, nutritional rickets is a major health problem. The aim of this study was to explore the magnitude of nutritional rickets among Saudi infants, and the various clinical presentations, as well as to address the possible operating risk factors behind the disease. We carried out a retrospective study at King Abdulaziz Medical City-King Fahad National Guard Hospital in Riyadh, Saudi Arabia. The records of Saudi infants under the age of 14 months over a 10-year period (between January 1990 and January 2000) were reviewed. Infor-mation collected included age, sex, clinical presentations, biochemical, radiological findings, infant nutrition, presence of other nutritional deficiencies and exposure to sunlight. There were 283 infants diagnosed with nutritional rickets due to Vitamin D deficiency (67% males) who were between 6 and 14 months of age. Among the total, 70% were exclusively breast-fed, and 23% were breast-fed until the age of 1 year. The most frequent clinical presentation was hypo-calcemic convulsions (34%) followed by chest infections (33%) and gastroenteritis (25%). In conclusion, nutritional rickets is still prevalent in Saudi Arabia with the primary etiology being vitamin D deficiency. Therefore we recommend that every infant, who is exclusively on breast-feeding, has routine supplement of vitamin D in the range of 200 IU/day (alone or as apart of multivitamin), started soon after birth until the time of weaning.


Asunto(s)
Estado Nutricional/fisiología , Raquitismo/epidemiología , Femenino , Humanos , Incidencia , Lactante , Masculino , Estudios Retrospectivos , Raquitismo/prevención & control , Factores de Riesgo , Arabia Saudita/epidemiología , Vitamina D/uso terapéutico
11.
J Pediatr Endocrinol Metab ; 13(7): 899-905, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10968478

RESUMEN

Ten patients with juvenile rheumatoid arthritis (JRA) and growth failure were treated with recombinant human growth hormone (GH) for 1 to 3 years at a dosage of 0.57 IU/kg/wk. All the patients had been on prednisone at a mean dosage of 4.12 mg p.o. daily. GH was low in one patient, two patients had a borderline level and seven patients had adequate response to provocative tests or post-sleep measurement. Serum IGF-I was found to be low in five of six patients. Mean growth velocity increased from 2.45 cm/yr to 4.79 cm/yr after 1 year's treatment with GH (P<0.004). Six patients continued on GH treatment for a second year and continued to have a better growth velocity, with a mean of 5.43 cm/yr (P<0.014). Two patients entered puberty during the second year of GH treatment. This study demonstrates the potential beneficial effect of GH treatment in patients with JRA with growth failure of systemic onset or polyarticular onset who are on prednisone. Further study is needed to determine the long-term effect of GH treatment on ultimate height.


Asunto(s)
Artritis Juvenil/tratamiento farmacológico , Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Preescolar , Femenino , Humanos , Lactante , Masculino
13.
Ann Trop Paediatr ; 17(4): 381-6, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9578800

RESUMEN

A 6-year-old girl had a group A beta-haemolytic streptococcal (GABS) throat infection and Henoch-Schonlein purpura (HSP). The clinical course was complicated by nephrotic syndrome due to crescentic glomerulonephritis, transient neurological symptoms due to focal ischaemia of the brain, and congestive cardiac failure due to myocarditis. The clinical presentation highlights the diversity of systemic involvement in HSP, the transient nature of apparently serious central nervous system involvement, and a possible role of GABS in its aetiology.


Asunto(s)
Vasculitis por IgA/microbiología , Infecciones Estreptocócicas/complicaciones , Streptococcus pyogenes , Niño , Femenino , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/microbiología , Humanos , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/microbiología , Síndrome Nefrótico/microbiología , Síndrome Nefrótico/patología , Radiografía , Ultrasonografía
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