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1.
Sci Rep ; 13(1): 11766, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474551

RESUMO

The objective of this research is to produce oil from the catalytic pyrolysis of waste polypropylene (WPP) using a low-cost natural catalyst. Three natural catalysts were examined, i.e. Kaolin, Hematite, and white sand. Different catalyst-to-plastic ratios were examined, i.e. 1:1, 1:2, 1:4, 1:6, and 1:8. The utilized catalysts were elementally analyzed using the XRF analysis and the surface area was analyzed by the BET multi-point method. The WPP thermal degradation behavior was investigated by the thermogravimetric analysis (TGA), then the generated liquid oil was analyzed using the gas chromatography-mass spectrometry (GC-MS) and the differential scanning calorimetry (DSC). Thermal cracking without a catalyst produced a yield of 70 wt% of liquid oil, and the maximum oil yield in case of using Hematite and white sand as a catalysts were 70 wt% and 68 wt%, respectively. However, the ratio of 1:2 of the Kaolin to the WPP produced the highest oil yield of 80.75 wt%, and the ratio of 1:8 of the white sand to the WPP produced the highest gas yield, i.e. 44 wt%. Using Kaolin in the catalytic pyrolysis of WPP produced oil with the lowest percentage of heavy oils, i.e. 25.98%, and the highest percentage of light oils, which is 25.37%, when compared to other catalysts such as Hematite and white sand. Kaolin has the lowest cost of oil production compared to Hematite and white sand, which is 0.28 $/kg of oil. Kaolin is an economical catalyst that improves the quality, as well as the quantity of the produced oil in comparison to Hematite, white sand and the non-catalytic case.

3.
PLoS One ; 15(1): e0226070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923252

RESUMO

Conjugated linoleic acid (CLA) is known for its multiple benefits including improvement of growth, increasing lean mass, and anti-carcinogenic effects. However, when used in long-term supplementations CLA does not improve semen parameters in boar and bull and reduces fertility in Japanese quails. The content of unsaturated fatty acids in dietary lipids plays a significant role in spermatogenesis owning the high proportion of unsaturated fatty acids in plasma membrane of sperms. Whether CLA plays a role in testicular tissue and epididymal fat is still unknown. Therefore, in this study we hypothesize that long-term supplementation of equal proportion of CLA isomer mix (c9,t11-CLA and t10,c12- CLA) in rabbit bucks might alter male reproductive potentials. Twelve V-Line weaned male rabbits were used in 26 weeks trial, rabbits were individually raised and randomly allocated into three dietary groups. Control group (CON) received a basal diet, a group received 0.5% CLA (CLA 0.5%), and a group received 1% CLA (CLA 1%). Rabbits were euthanized at the end of the trial and several parameters were evaluated related to growth, semen quality, and testicular and epididymal tissue histopathology and transcriptome. The long-term supplementation of CLA increased feed intake by 5% and body weight by 2-3%. CLA 1% decreased sperm progressive motility. In testicular tissue L-carnitine and α-tocopherol were decreased by CLA supplementation. In epididymal fat, CLA tended to decrease concentration of polyunsaturated fatty acids, the expression of SCD5 gene was upregulated by CLA 1% and CASP3 gene was upregulated by CLA 0.5%. Transcription of PPARG was downregulated by CLA. Feeding 1% CLA also decreased testicular epithelial thickness. Long-term supplementation of CLA modestly enhanced male rabbit growth, but negatively impacted male reproduction, especially at high dose of CLA.


Assuntos
Apoptose , Ácidos Linoleicos Conjugados , Motilidade dos Espermatozoides , Espermatozoides , Animais , Masculino , Coelhos , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Carnitina/metabolismo , Suplementos Nutricionais , Regulação para Baixo/efeitos dos fármacos , Epididimo/metabolismo , Epididimo/patologia , Ácidos Graxos Insaturados/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , PPAR gama/genética , PPAR gama/metabolismo , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Testículo/metabolismo , Testículo/patologia , Testosterona/sangue , Transcriptoma/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
4.
Int J Biol Macromol ; 147: 1029-1040, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31751747

RESUMO

Red palm weevil (RPW), Rhynchophorus ferrugineus, is one of the most destructive pests of cultivated palm trees. The application of synthetic insecticides is currently a main strategy for RPW control. In this study we estimated the distribution of acetylcholinesterase (AChE), as a detoxifying enzyme and the target site of inhibition by insecticides, using ASChI as substrate in different organs of the pest including whole gut, cuticle, fat body, head and haemolymph. The activity ranged from 314.9 to 3868 U in individual organs while the specific activity ranged from 99 to 340.8 U/mg proteins; the cuticle had the highest enzyme level. During larval development, the 11th instar larvae had the highest enzyme content with 5630 U in the cuticle, with a specific activity of 140 U/mg protein. The two major AChE isoenzymes were purified by chromatography on gel filtration and ion exchange columns. They had specific activities of 3504.3 and 2979 U/mg protein, molecular weights of 33 and 54 kDa and activation energies of 8.3 and 4.4 kcal/mol, respectively. Both isoenzymes had monomeric forms, optimum activity at pH 8.0 and 40 °C, were completely inhibited by Hg2+ and Cu2 and showed similar trends towards the inhibitors eserine, BW284C51 and iso-OMPA. The catalytic properties were compared with those previously recorded for different insect species. This work will pave the way for more studies for improving the understanding of insecticide resistance and developing the field application of synthetic insecticides for controlling R. ferrugineus to ensure successful application.


Assuntos
Acetilcolinesterase/química , Acetilcolinesterase/isolamento & purificação , Proteínas de Insetos/química , Proteínas de Insetos/isolamento & purificação , Gorgulhos/enzimologia , Animais , Catálise , Cátions , Cobre/química , Hemolinfa , Concentração de Íons de Hidrogênio , Hidrólise , Inseticidas , Isoenzimas/química , Cinética , Larva , Mercúrio/química , Peso Molecular , Especificidade por Substrato , Temperatura
5.
Epidemiol Infect ; 146(13): 1625-1627, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30056812

RESUMO

Zika virus infection in humans has been linked to severe neurological sequels and foetal malformations. The rapidly evolving epidemics and serious complications made the frequent updates of Zika virus mandatory. Web search query has emerged as a low-cost real-time surveillance system to anticipate infectious diseases' outbreaks. Hence, we developed a prediction model that could predict Zika-confirmed cases based on Zika search volume in Google Trends. We extracted weekly confirmed Zika cases of two epidemic countries, Brazil and Colombia. We got the weekly Zika search volume in the two countries from Google Trends. We used standard time-series regression (TSR) to predict the weekly confirmed Zika cases based on the Zika search volume (Zika query). The basis TSR model - using 1-week lag of Zika query and using 1-week lag of Zika cases as a control for autocorrelation - was the best for predicting Zika cases in Brazil and Colombia because it balanced the performance of the model and the advance time in the prediction. Our results showed that we could use Google search queries to predict Zika cases 1 week earlier before the outbreak. These findings are important to help healthcare authorities evaluate the outbreak and take necessary precautions.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Ferramenta de Busca/estatística & dados numéricos , Infecção por Zika virus/epidemiologia , Brasil/epidemiologia , Colômbia/epidemiologia , Humanos , Internet , Zika virus , Infecção por Zika virus/psicologia
6.
Public Health ; 159: 78-88, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29627116

RESUMO

OBJECTIVE: To systematically review the evidence for an association between maternal depression and the risk of diarrheal illness in infants. STUDY DESIGN: This study is a meta-analysis. METHODS: Nine databases were searched systematically for studies that investigated the risk of diarrheal illness in infants born to mothers with depression. RESULTS: Our search strategy yielded 10 studies of the association between maternal depression and the risk of diarrheal illness in infants: eight studies of postnatal depression, two studies of antenatal depression, and one study of perinatal depression. Our meta-analysis showed that infants born to mothers with postnatal depression were more likely to develop diarrheal illness (odds ratio [OR] = 1.902, 95% confidence interval [95% CI] = 1.385-2.612, P < 0.001, n = 18,585). A similar trend was noted for antenatal depression (OR = 2.703, 95% CI = 0.920-7.942, P = 0.071, n = 583). Only one study reported an association between perinatal depression and risk of diarrhea in infants (OR = 1.848, log OR = 0.614, standard error = 0.093, n = 107,587). CONCLUSIONS: Only a few studies so far have identified an association between maternal depression and risk of diarrhea in infants. The evidence available to date suggests that infants born to mothers with depression are more likely to develop diarrhea than infants whose mothers do not have depression.


Assuntos
Transtorno Depressivo/epidemiologia , Diarreia Infantil/epidemiologia , Mães/psicologia , Feminino , Humanos , Lactente , Risco
7.
Parasitol Res ; 116(9): 2393-2406, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28668985

RESUMO

Toxoplasma gondii has subpopulation structures in different geographical regions caused by less frequent sexual recombination, population sweeps, and biogeography. The majority of strains isolated in North America and Europe fall into one of three clonal lineages, referred to as types I, II, and III. So far, little is known about genetics of Toxoplasma strains in Africa. The present study aimed to determine the genotype of Toxoplasma strains obtained directly from trophoblastic/placental tissues of 29 complicated pregnant women using multilocus nested-PCR-RFLP technique depending on four independent genetic loci (5' SAG2 and 3' SAG2), SAG3, GRA6, and BTUB genes. All samples gave positive amplicons at 5'-3' SAG2 and SAG3 genes. Meanwhile, no amplification products were observed in 12 (41.37%) and 10 (34.48%) samples with GRA6 and BTUB genes, respectively. The restriction pattern revealed the presence of genotype I in all samples, except one sample, which revealed atypical genotype with unusual restriction pattern at 3' SAG2 gene. The negative amplifications in some samples could be due to presence of mutations or polymorphisms in the primer binding sites of these isolates, raising the possibility of mixed or recombinant genotypes. To the best of our knowledge, this is the first time to perform genotype analysis study based on Multiplex nPCR-RFLP technique for genetic characterization of T. gondii in Egypt. Besides, it is the first time to prove that the most prevalent strain of T. gondii, responsible for congenital toxoplasmosis in Upper Egypt, is the highly virulent type I. Atypical genotype was detected as well.


Assuntos
Complicações Parasitárias na Gravidez/epidemiologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Congênita/epidemiologia , Adulto , África/epidemiologia , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/genética , Egito/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Genótipo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Epidemiologia Molecular/métodos , Tipagem Molecular/métodos , América do Norte/epidemiologia , Filogenia , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição/genética , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Estudos Prospectivos , Toxoplasma/isolamento & purificação , Toxoplasmose Congênita/parasitologia , Adulto Jovem
8.
Ultrastruct Pathol ; 36(6): 377-80, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23216235

RESUMO

Leprosy is a devastating disease caused by Mycobacterium leprae. It includes a spectrum of clinicopathological lesions. Neuritic leprosy with caseation necrosis (abscess) manifesting as a soft tissue mass is a relatively rare presentation of leprosy. Here, the authors report their experience with three patients with neuritic leprosy. The patients presented with swellings in the right ulnar nerve, the right great auricular nerve, and the temporal branch of the right sixth cranial nerve. The clinical impression was that of tumorous masses. Gross examination of the biopsy specimens revealed caseous necrotic materials. Further histological evaluation disclosed tuberculoid granulomas with extensive caseation necrosis. Stains for acid-fast bacilli were positive in the third case. A comparison between the caseation encountered in the tuberculoid neurotic leprosy and the neurolysis of lepromatous neurotic leprosy has been also discussed. The findings here emphasize "mass lesion with necrosis" as a possible clinical presentation of the neuritic leprosies. The clinicopathologic features were addressed and the relevant literature was reviewed.


Assuntos
Nervo Abducente/patologia , Abscesso/patologia , Hanseníase Dimorfa/patologia , Hanseníase Tuberculoide/patologia , Neurite (Inflamação)/patologia , Pele/patologia , Nervo Ulnar/patologia , Nervo Abducente/microbiologia , Abscesso/microbiologia , Adolescente , Biópsia , Feminino , Humanos , Hanseníase Dimorfa/microbiologia , Hanseníase Tuberculoide/microbiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Necrose , Neurite (Inflamação)/microbiologia , Pele/microbiologia , Nervo Ulnar/microbiologia
9.
Comp Biochem Physiol C Toxicol Pharmacol ; 146(3): 314-24, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17531543

RESUMO

Acetylcholinesterases (AChEs) have been estimated in the infective juveniles (IJs) of eight different strains of heterorhabditid nematodes. The enzyme content ranged from 45.6 to 421.3 units/10(5) IJs with specific activity 34.0 to 82.6 units/mg protein. The isoenzyme patterns revealed the existence of two-slow-moving isoforms. Heterorhabditis bacteriophora AChE1A has been purified from the IJs of the heterorhabditid nematode strain of the highest enzymatic activity to homogeneity by ammonium sulfate precipitation, gel filtration on Sephacryl S-200 and DEAE-Sepharose. The specific activity of the purified enzyme was 1378.1 units/mg protein with purification fold 17.5 over crude extract. The enzyme has a pH optimum at 7.5. The optimum temperature for enzyme activity and stability was 35 degrees C. The activation energy was calculated to be 9.0 kcal/mol. The enzyme hydrolyzes acetylthiocholine (AcSCh), propionylthiocholine (PrSCh), S-butyrylthiocholine (BuSCh) and benzoylthiocholine (BzSCh) iodides with relative rate 100, 74.6, 41.7 and 22.2%, respectively. It displayed an apparent Michaelis-Menten behavior in the concentration range from 0.1 to 2 mM for the three former substrates with Km values 0.27, 0.42 and 0.59 mM, respectively. H. bacteriophora ChE1A is an AChE since it hydrolyzed AcSChI at higher rate than the other substrates and displayed excess substrate inhibition with AcSChI at concentrations over 2 mM. It was inhibited by eserine and BW284C51, but not by iso-OMPA. Its biochemical properties were compared with those reported for different species of insects as target hosts for heterorhabditid nematodes and animal parasitic nematodes.


Assuntos
Acetilcolinesterase/isolamento & purificação , Acetilcolinesterase/metabolismo , Estágios do Ciclo de Vida/fisiologia , Rhabditoidea/enzimologia , Acetiltiocolina/metabolismo , Animais , Benzoilcolina/análogos & derivados , Benzoilcolina/metabolismo , Butiriltiocolina/metabolismo , Hidrólise , Especificidade por Substrato , Tiocolina/análogos & derivados , Tiocolina/metabolismo
10.
J Clin Pathol ; 60(1): 62-71, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17213348

RESUMO

BACKGROUND: Bullous skin lesions are characterised by the presence of intraepidermal or subepidermal bullae. Although inflammatory cell infiltrate is a constant feature in these lesions, their immunophenotypic characterisation is still incomplete. AIM: To determine whether the development of bullous skin diseases is associated with changes in the inflammatory cell infiltrate. MATERIALS AND METHODS: 34 cases representing lesions with both intraepidermal and subepidermal bullae were examined using immunoperoxidase staining methods and antibodies targeting antigens for histiocytes (CD68), B cells (CD20+), T cells (CD3+), T cells with cytotoxic potential (T cell intracellular associated antigen, TIA1+) and activity (granzyme B, GRB+). The adjacent normal skin (lesions) and an additional five cases of normal skin were also examined (controls). RESULTS: The transition from normal skin to lesional skin (lesions with intraepidermal and subepidermal bullae) was associated with a significant increase (p< or =0.05) in the density of total inflammatory cell infiltrate, CD68+ cells, CD3+ T lymphocytes, CD20+ B lymphocytes, TIA1+ -resting cytotoxic T cells and GRB+ T cells with cytotoxic activity. CONCLUSIONS: The increase in inflammatory cell infiltrate during the transition from normal to lesional skin may reflect the presence of an increased antigenicity of the lesional cells or a response to some basement membrane components. CD68+ and CD3+ cells, especially the resting cytotoxic ones, achieved numerical dominance in these lesions. Cell-mediated immunity seems to have critical role in the development of these lesions.


Assuntos
Dermatopatias Vesiculobolhosas/imunologia , Adolescente , Adulto , Idoso , Complexo CD3/análise , Criança , Pré-Escolar , Epiderme/patologia , Feminino , Histiócitos/patologia , Humanos , Imunidade Celular , Técnicas Imunoenzimáticas/métodos , Imunofenotipagem , Subpopulações de Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Dermatopatias Vesiculobolhosas/patologia , Linfócitos T Citotóxicos/patologia
11.
Eur J Cancer Prev ; 15(1): 64-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16374232

RESUMO

Although melanocytic skin lesions have been recognized since antiquity, their literature was limited to Caucasians. To date, the clinicopathologic features of these lesions in Egyptians are still unknown. To define these features, diagnostic records of the melanocytic skin lesions received at the Pathology Department, Assuit University Hospitals (1989-2004) were reviewed. The lesions examined included 12 benign naevi (BN), 10 dysplastic naevi (DN), and 21 cutaneous malignant melanomas (CMMs). The DN and CMMs were more common in men than in women (2 : 1 and 1.5 : 1, respectively) while BN were more common in women (2 : 1). The average age incidence was 33+/-5, 38+/-7 and 54+/-3 years, for BN, DN and CMM, respectively. The lower limb (13/21, 62%), head and neck (7/21, 33%) were the most common sites for CMMs. The average size (mm) was 2+/-0.3, 4+/-0.6 and 21+/-0.3 for BN, DN and CMMs, respectively. Recurrence occurred in 10% of CMMs. Histologically, CMMs were of nodular type and composed of epithelioid (7/21, 33%), spindle cells (1/21, 5%), or mixed cells (13/21, 62%). The mean tumour thickness (Breslow) was 6+/-0.5 mm. CMMs included two of 21(9%), three of 21(14%), six of 21(38%), and 10 of 21(38%) with Clark level II, III, IV and V. In Egypt, CMM is the third most common cutaneous neoplasm following squamous and basal cell carcinomas. Compared with Western societies, melanoma has a male sex predilection, similar histological features but different topographical distribution and rare incidence. The striking difference from Western series is the incidence of nodular melanoma - in the West this represents 15-30% of melanomas, with superficial spreading being the majority. Another key difference from the West is the 'sun-bed' culture of the West and the desire to have suntans. This is the first study that reports the clinicopathologic features of melanocytic skin lesions in Egypt.


Assuntos
Síndrome do Nevo Displásico/patologia , Melanoma/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Adulto , Distribuição por Idade , Árabes , Feminino , Humanos , Masculino , Melanoma/epidemiologia , Melanoma/etiologia , Pessoa de Meia-Idade , Nevo Pigmentado/epidemiologia , Nevo Pigmentado/etiologia , Estudos Retrospectivos , Distribuição por Sexo , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Raios Ultravioleta/efeitos adversos , População Branca
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