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1.
Molecules ; 28(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37630414

RESUMO

High concentrations of graphene oxide (GO), a nanoparticle substance with rapid manufacturing development, have the ability to penetrate the soil surface down to the mineral-rich subsurface layers. The destiny and distribution of such an unusual sort of nanomaterial in the environment must therefore be fully understood. However, the way the chemistry of solutions impacts GO nanoparticle adsorption on clay minerals is still unclear. Here, the adsorption of GO on clay minerals (e.g., bentonite and kaolinite) was tested under various chemical conditions (e.g., GO concentration, soil pH, and cation valence). Non-linear Langmuir and Freundlich models have been applied to describe the adsorption isotherm by comparing the amount of adsorbed GO nanoparticle to the concentration at the equilibrium of the solution. Our results showed fondness for GO in bentonite and kaolinite under similar conditions, but the GO nanoparticle adsorption with bentonite was superior to kaolinite, mainly due to its higher surface area and surface charge. We also found that increasing the ionic strength and decreasing the pH increased the adsorption of GO nanoparticles to bentonite and kaolinite, mainly due to the interaction between these clay minerals and GO nanoparticles' surface oxygen functional groups. Experimental data fit well to the non-linear pseudo-second-order kinetic model of Freundlich. The model of the Freundlich isotherm was more fitting at a lower pH and higher ionic strength in the bentonite soil while the lowest R2 value of the Freundlich model was recorded at a higher pH and lower ionic strength in the kaolinite soil. These results improve our understanding of GO behavior in soils by revealing environmental factors influencing GO nanoparticle movement and transmission towards groundwater.

2.
Adv Exp Med Biol ; 1395: 309-313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527654

RESUMO

Connexin 43 (Cx43) is a multifunction protein that forms gap junction channels and hemichannels and is suggested to play an essential role in oxygen-glucose deprivation, induced via neuroinflammation during astrocytoma expansion into healthy tissue. To prove this assumption we studied connexin 43 localisation and ultrastructure of gap junctions in samples of malignant brain tumour (anaplastic astrocytomas grade III). For confocal laser microscopy, vibratome sections of tumour fragments were incubated in a mixture of primary antibodies to connexin 43 and glial fibrillary acidic protein (GFAP), then in a mixture of secondary antibodies conjugated with a fluorescent label. After the immunofluorescence study, sections were washed in phosphate buffer, additionally postfixed with 1% OsO4 solution, dehydrated and embedded in epoxy resin by a plane-parallel method. Ultra-thin sections obtained from these samples were contrasted with uranyl acetate and lead citrate and viewed under a Jem 1011 electron microscope. Confocal laser examination detected a positive reaction to Cx43 in the form of point fluorescence. These points were of various sizes. Most of them were localised around or at the intersection of small processes containing GFAP. Electron microscopy of the tumour samples containing the most significant number of Cx43 revealed single and closely spaced gap junctions with a typical ultrastructure on the processes and bodies of tumour cells. Sequential analysis in the fields of view revealed 62 gap junctions in the area of 100 µm2. Numerous gap junctions in anaplastic astrocytomas revealed in our study may indicate electrotonic and metabolic transmission between glioma cells, possibly promoting its progression.


Assuntos
Astrocitoma , Conexina 43 , Junções Comunicantes , Microscopia Confocal , Microscopia Eletrônica , Humanos , Astrocitoma/genética , Astrocitoma/metabolismo , Astrocitoma/patologia , Astrocitoma/ultraestrutura , Conexina 43/genética , Conexina 43/metabolismo , Conexina 43/ultraestrutura , Junções Comunicantes/genética , Junções Comunicantes/metabolismo , Junções Comunicantes/ultraestrutura , Lasers
3.
Acta Neurochir (Wien) ; 164(6): 1653-1657, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35171374

RESUMO

Malignant ischemic infarction in the territory supplied by the middle cerebral artery is an extremely severe form of ischemic stroke associated with development of massive uncontrollable postischemic edema of the affected cerebral hemisphere; the end result of which is development of transtentorial herniation and death. METHOD: The surgical technique of performance of decompressive hemicraniectomy involves removal of an extensive bone flap in the fronto-temporo-parieto-occipital zone with resection of the temporal squama and of the greater wing of the sphenoid bone to visualize the level of entrance of the middle meningeal artery to the cranial cavity, which, in its turn, allows resection of the upright margin of the middle cranial fossa. Decompressive hemicraniectomy is supplemented with resection of the temporal pole and tentoriotomy. CONCLUSION: Performance of decompressive hemicraniectomy in combination with resection of the resection of the temporal pole and tentoriotomy is an effective surgical method of treatment of malignant ischemic stroke in the territory supplied by the middle cerebral artery, capable of reducing the lethality rate during the postoperative period.


Assuntos
Craniectomia Descompressiva , AVC Isquêmico , Craniectomia Descompressiva/métodos , Humanos , Infarto da Artéria Cerebral Média/cirurgia , Artéria Cerebral Média/cirurgia , Lobo Temporal/cirurgia , Resultado do Tratamento
4.
Ultrastruct Pathol ; 44(2): 227-236, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32148147

RESUMO

The phenomenon of unstable expression of gap junction's proteins connexins remains a "visiting card" of astrocytic tumors with various degrees of malignancy. At the same time, it stays unclear what is detected by the positive expression of connexins in astrocytic tumors: gap junctions, hemi-channels, or connexin proteins in cytosol. In the present work, for the first time, we demonstrate an ultrastructural evidence of gap junctions in pleomorphic xanthoastrocytoma, a rare primary brain tumor, the intercellular characteristics of which are poorly studied and remain very discursive and controversial. The primary tumor mass was resected during craniotomy from a 57-old patient diagnosed with pleomorphic xanthoastrocytoma Grade II based on the histopathological analysis. The immunohistochemical study was conducted with primary antibodies: Neurofilament, Myelin basic protein, Glial fibrillary acidic protein, and Synaptophysin. For electron microscopic examination fragments of tumor tissue were fixed in a glutaraldehyde, postfixed in a 1% OsO4, dehydrated and embedded into resin. After the detailed clinical, histological, and immunohistochemical study we revealed some ultrastructural characteristics of the tumor, as well as the first evidence of direct intercellular connection between the tumor cells via gap junctions. Regularly arranged gap junctions connected the somas of xanthastrocytes with dark cytoplasm containing lipid drops. Besides the localization between the cell bodies, from one to several gap junctions were found between the branches of xanthoastrocytoma in tumor intercellular space in close proximity to tumor cell. Our results may indicate gap junctions as a possible structure for intercellular communication between pleomorphic xanthoastrocytoma cells.


Assuntos
Astrocitoma/ultraestrutura , Neoplasias Encefálicas/ultraestrutura , Junções Comunicantes/ultraestrutura , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade
5.
J Egypt Soc Parasitol ; 45(3): 633-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26939242

RESUMO

A cohort of children presented with pelvic inflammatory diseases (gastrointestinal and/or genitourinary surgical conditions) and had concomitant infection with E. vermicularis. To find out this relationship, a total of 135 patients suffering from different gastrointestinal and genitourinary surgical conditions were selected from Departments of Surgery and Gynecology. They were subjected to stool analysis, peri-anal swabs and blood examination mainly for eosinophilia. The results showed that 26 patients out of 135 (19.2%) had. E. vermicularis with high eosinophilia in 30 cases (22.2%). Identification of E. vermicularis by peri-anal swab test in the cohort was successful (16.30%). Males were more affected than females with ratio 2.2:1 and age mean 7.13 +/- 1.92. As to residence and housing, rural children with bad housing (73.08% & 88.46% respectively) were more affected than those living in urban areas with healthy housing (26.92% and 11.54% respectively).


Assuntos
Enterobíase/complicações , Enterobius , Infecção Pélvica/complicações , Animais , Criança , Pré-Escolar , Enterobíase/epidemiologia , Feminino , Humanos , Masculino , Infecção Pélvica/epidemiologia , Infecção Pélvica/parasitologia , Fatores de Risco
6.
J Egypt Soc Parasitol ; 43(2): 463-70, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24260825

RESUMO

Ninety children infected with Cryptosporidium parvum attending Al-Azhar University Teaching Hospital (Assuit) were chosen (60 males & 30 females) with age range from 6 months to ten years. The patients were divided into two groups of 45 patients for each (G1 & G2). All patients suffered from chronic diarrhea for more than fifteen days. Cross-matched 45 children suffering from chronic diarrhea were used as a control group (G3). Stool samples were collected and examined for detection of Cryptosporidium oocysts using Sheather's sugar and Modified Ziehl-Nelseen stain techniques. The first group (G1) received Nitazoxanide (100 mg and 200 mg every 12 hours for 3 days for children aged 6 months to 3 years and chil dren aged 4 to 10 years respectively), G2 received Paromomycin (25 mg/kg/day for 2 weeks). Third group received placebo. Significant improvement and shortening of the duration of diarrhea occur in G1; of 45 patients received Nitazoxanide 39 cases showed complete clinical and laboratory cure (86.6%), 5 cases showed clinical improvement with reduction in the number of oocysts and 1 case showed no cure. In G2 of 45 cases received Paromomycin 31 cases showed complete cure (68.8%), 8 cases showed clinical improvement with reduction of oocysts number and 6 cases were not cured. Nitazoxanide proved highly effective than Paromomycin in cryptosporidiosis.


Assuntos
Criptosporidiose/tratamento farmacológico , Paromomicina/uso terapêutico , Tiazóis/uso terapêutico , Animais , Pré-Escolar , Feminino , Hospitalização , Humanos , Lactente , Masculino , Nitrocompostos , População Rural , População Urbana
7.
East Mediterr Health J ; 16(4): 402-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20795424

RESUMO

This study assessed the knowledge and practices about folic acid in pregnancy among pregnant women attending 2 main maternal and child health centres in Abu Dhabi. The majority of the 277 interviewed mothers (79.1%) had heard of folic acid and 46.6% had accurate knowledge about the role of folate in preventing neural tube defects. There were good practices regarding folate supplementation in the current pregnancy; most of the interviewed mothers took it daily and in the recommended dose. However, only a minority took it prior to pregnancy. Education, irrespective of age or parity, was the major factor determining better knowledge of folic acid in pregnancy.


Assuntos
Atitude Frente a Saúde , Ácido Fólico/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Defeitos do Tubo Neural/prevenção & controle , Gestantes/psicologia , Complexo Vitamínico B/uso terapêutico , Adulto , Escolaridade , Comportamento Alimentar , Feminino , Humanos , Modelos Logísticos , Paridade , Cuidado Pré-Concepcional , Gravidez , Cuidado Pré-Natal , Automedicação , Inquéritos e Questionários , Emirados Árabes Unidos , População Urbana
8.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117885

RESUMO

This study assessed the knowledge and practices about folic acid in pregnancy among pregnant women attending 2 main maternal and child health centres in Abu Dhabi. The majority of the 277 interviewed mothers [79.1%] had heard of folic acid and 46.6% had accurate knowledge about the role of folate in preventing neural tube defects. There were good practices regarding folate supplementation in the current pregnancy; most of the interviewed mothers took it daily and in the recommended dose. However, only a minority took it prior to pregnancy. Education, irrespective of age or parity, was the major factor determining better knowledge of folic acid in pregnancy


Assuntos
Educação em Saúde , Ácido Fólico , Gravidez , Paridade , Conhecimentos, Atitudes e Prática em Saúde
9.
Gastroenterology ; 130(2): 304-11, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16472586

RESUMO

BACKGROUND & AIMS: Irritable bowel syndrome (IBS) is a functional disorder with an etiology that has been linked to both psychological stress and infection. The primary aim of this study was to examine the hypothalamic-pituitary-adrenal axis in patients with IBS and to relate such response to plasma cytokine profiles. METHODS: A total of 151 subjects, 76 patients and 75 controls, were recruited. The patients with IBS were diagnosed according to Rome II criteria. Forty-nine patients and 48 matched controls had cytokine levels measured, and a subset of 21 patients and 21 controls also underwent a corticotropin-releasing hormone (CRH) stimulation test with plasma levels of adrenocorticotropic hormone (ACTH) and cortisol measured. The remaining 27 patients and 27 controls underwent a dexamethasone (1 mg) challenge. RESULTS: Cortisol and the proinflammatory cytokines interleukin (IL)-6 (together with its soluble receptor) and IL-8 were elevated in all IBS subgroups (diarrhea predominant, constipated, and alternators), although the elevation was most marked in the constipated subgroup. There was no alteration in the anti-inflammatory cytokine IL-10. Following CRH infusion, an exaggerated release of both ACTH and cortisol was observed in patients with IBS. There was a significant correlation between the ACTH response (deltaACTH) and the IL-6 levels. A similar relationship existed between the deltaACTH/deltacortisol ratio and the IL-6 levels. Dexamethasone suppression of cortisol was similar in patients and controls. CONCLUSIONS: IBS is characterized by an overactivation of the hypothalamic-pituitary-adrenal axis and a proinflammatory cytokine increase.


Assuntos
Citocinas/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Intestinos/fisiopatologia , Síndrome do Intestino Irritável/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Consumo de Bebidas Alcoólicas , Biomarcadores/sangue , Dexametasona , Feminino , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Irlanda , Síndrome do Intestino Irritável/sangue , Masculino , Dor , Valores de Referência
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