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1.
Biochemistry (Mosc) ; 88(11): 1956-1969, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38105212

RESUMO

Euphorbiaceae, also known as the spurge family, is a large group of flowering plants. Despite being tropical natives, they are now widespread. Due to its medicinal and commercial importance, this family of plants attracted a lot of attention in the scientific community. The distinctive characteristic of the family is production of milky latex, which is a rich source of several lectins, the proteins that bind carbohydrates. Although their function is unclear, they are believed to defend plants against damaging phytopathogenic microorganisms, insects, and predatory animals. Additionally, they serve as crucial metabolic regulators under a variety of stressors. Detection, separation, purification, and characterization of lectins from the Euphorbiaceae family - mostly from the latex of plants - began over 40 years ago. This effort produced over 35 original research papers that were published. However, no systematic review that compiles these published data has been presented yet. This review summarizes and describes several procedures and protocols employed for extraction and purification of lectins belonging to this family. Physicochemical properties and biological activities of the lectins, along with their medicinal and pharmacological properties, have also been analyzed. Additionally, using examples of ricin and ricin agglutinin, we have structurally analyzed characteristics of the lectin known as Ribosome Inactivating Protein Type II (RIP-Type II) that belongs to this family. We anticipate that this review article will offer a useful compendium of information on this important family of lectins, show the scientists involved in lectin research the gaps in our knowledge, and offer insights for future research.


Assuntos
Euphorbiaceae , Ricina , Animais , Ricina/química , Lectinas de Plantas/farmacologia , Látex/química , Plantas
2.
SAGE Open Med ; 11: 20503121231187736, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37489137

RESUMO

Objective: The continuing COVID-19 pandemic is a coronavirus-related health emergency (severe acute respiratory syndrome coronavirus 2). Inadequate efforts are still being made to address the illness situation in Libya, and this must change. To address these issues, we looked into the demography and trend of the disease as well as the potential risk factors for infection. Methods: This study is a retrospective case-control study conducted online among 616 COVID-19 patients. The p0.05 value, odds ratios, and 95% confidence intervals were calculated and analyzed from the drawn data. Results: Males were at high risk of COVID-19 than females (odds ratio = 1.3, 95% confidence interval: 1.042-1.622; p = 0.02). Anosmia and ageusia were more prominent in females. Patients with an "AB" blood group are significantly susceptible to infection. Adults (31 and above) are highly liable to infection. The univariate logistic regression analysis revealed that smoking is a risk factor for those above 60 years (odds ratio = 2.228, 95% confidence interval: 1.145-4.336; p = 0.018). Individuals with chronic diseases such as diabetes and/or hypertension are more prone to COVID-19 (odds ratio = 10.045, 95% confidence interval: 3.078-32.794; p = 0.000 and odds ratio = 11.508, 95% confidence interval: 3.930-33.695; p = 0.000, respectively). Conclusion: This study provided for the first time the demographic data and the trend of COVID-19 infection in Libya, which will assist the stakeholders and governmental bodies in planning protection strategies against the pandemic.

3.
Saudi J Biol Sci ; 30(6): 103676, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37213699

RESUMO

The date palm, Phoenix dactylifera, is a vital crop in nations in the Middle East and North Africa. The date palm was thought to have outstanding traditional medicinal value because it was abundant in phytochemicals with diverse chemical structures. The date palm's ability to withstand harsh environments could be partly attributed to a class of proteins known as lectins, which are carbohydrate-binding proteins that can bind sugar moieties reversibly and without changing their chemical structures. After scanning the genome of P. dactylifera (GCF 009389715.1), this in silico study discovered 196 possible lectin homologs from 11 different families, some specific to plants. At the same time, others could also be found in other kingdoms of life. Their domain architectures and functional amino acid residues were investigated, and they yielded a 40% true-lectin with known conserved carbohydrate-binding residues. Further, their probable subcellular localization, physiochemical and phylogenetic analyses were also performed. Scanning all putative lectin homologs against the anticancer peptide (ACP) dataset found in the AntiCP2.0 webpage identified 26 genes with protein kinase receptors (Lec-KRs) belonging to 5 lectin families, which are reported to have at least one ACP motif. Our study offers the first account of Phoenix-lectins and their organization that can be used for further structural and functional analysis and investigating their potential as anticancer proteins.

4.
Saudi Med J ; 42(9): 969-974, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34470834

RESUMO

OBJECTIVES: To identify ribosome protein L5 gene variants and the risk of hepatic vein thrombosis in Saudi patients. METHODS: A case-control study was conducted during the period of May 2018 to September 2019. Sixty-five patient cases of hepatic vein thrombosis (HVT) were chosen, and 50 healthy individuals of the same ages and both gender were set as a control group. The genotype of the gene RPL5 was determined by PCR please provide abbreviation in full and capillary electrophoresis. Sanger sequencing for genetically screened variants was applied for the RPL5 gene. RESULTS: Alleles A at variant rs182018447 and T allele at variant rs559377519 were strongly corelated (p=0.009 and p=0.037, respectively) with the risk of HVT. The genotype frequencies of the RPL5 gene, the A/A genotypes at rs182018447 and T/T at rs559377519 were associated with HVT (p=0.000 and p=0.004; respectively) and an increase in risk for HVT among these patients. Please rephrase the highlighted text without using the word respectively. CONCLUSION: Our findings indicate that the 5 genetic novel variants examined in the RPL5 gene were associated with a risk of HVT in all our Saudi cases. Additionally, the A/A at rs182018447 and T/T at rs559377519 genotypes were substantially susceptible to HVT in all these patients.


Assuntos
Síndrome de Budd-Chiari , Proteínas Ribossômicas/genética , Alelos , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Arábia Saudita/epidemiologia
5.
Blood Purif ; 45(1-3): 201-207, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29478066

RESUMO

BACKGROUND: The burden of acute kidney injury (AKI) is high in Africa. While there are no reliable statistics about AKI in Africa, the Global Snapshot Study of the 0by25 initiative of the International Society of Nephrology has determined dehydration, infections, animal envenomation, and complications during pregnancy as the main causes. METHODS: This study was conducted at the Soba University Hospital (SUH), Khartoum, Sudan, a tertiary referral center. We included all hemodialysis patients treated for AKI at SUH between -January 1, 2013 and December 31, 2014 in the study. We reviewed patients' hospital records and characterized pathogenesis, treatment, and patient outcomes. In addition, we investigated survival by Kaplan-Meier and Cox regression analysis. RESULTS: Out of 520 patients who received emergency HD, 71 patients (14%) had AKI (age 40.6 ± 17.3 years, 56.5% were males). Glomerular and tubular-interstitial diseases were the leading cause of AKI, followed by envenomation and intoxication by hair dye. Patients received a median of 5 dialysis sessions for a median of 8 days. In 32 patients (45%) renal function recovered, 10 patients (14%) died, and 29 patients (41%) remained dialysis-dependent. Mortality was significantly higher in females compared to men (hazard ratio 4.1 [95% CI 1.02-16.67]). Outcomes were worse in patients with pre-renal AKI and intoxications. CONCLUSION: Our results indicate a higher mortality in females and in patients with pre-renal AKI and intoxications. Awareness of factors associating with poor outcomes is central to diagnostic and therapeutic efforts, and must be considered in the design of initiatives to reduce risk factors and improve outcomes of AKI in developing countries.


Assuntos
Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Complicações na Gravidez/mortalidade , Complicações na Gravidez/terapia , Diálise Renal , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Sudão , Taxa de Sobrevida
6.
J Mol Recognit ; 30(2)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27774692

RESUMO

Three isolectins denoted hereforth MBaL-30, MBaL-60, and MBaL-80 were isolated from seeds extract of Momordica balsamina by 30%, 60%, and 80% ammonium sulfate saturations, respectively. The native molecular weights of these lectins, as judged by gel filtration, were 108, 56, and 160 kDa, respectively. On SDS-PAGE, under reduced condition, 27 kDa band was obtained for all isolectins. The lectins hemagglutinating activities were variably inhibited by d-galactose (minimum inhibitory concentrations = 12.5mM, 50mM, and 0.391mM, respectively). MBaL-30 and -60 could agglutinate all human blood types with slight preference for the A and O blood groups, whereas MBaL-80 did not agglutinate B and AB blood types. The 3 isolectins were purified from crude seeds extract, collectively, in a single step on the affinity matrix Lactamyl-Seralose 4B; this purified lectin fraction, which contains all isolectins, is termed MBaL. The N-terminal of MBaL till the 25th amino acid was NLSLSELDFSADTYKSFIKNLRKQL, which shares 88% sequence identity with Momordica charantia lectin type-2 ribosomal inactivating protein from Momordica charantia and 50% with momordin II from Momordica balsamina. MBaL retained 100% activity at up to 50°C for 30 minutes. MBaL-30 and MBaL-60 exhibited maximum activities in the pH range between 4 and 8, while MBaL-80 was showing maximum activity in the pH range between 3 and 5. Treatment of MBaL-30 and MBaL-60 with EDTA completely abolished their hemagglutinating activities. Addition of Zn and Fe ions to the ethylenediaminetetraacetic acid-treated MBaL-30 and MBaL-60 lectins did not only regained the loss of activity but also resulted in 200% to 300% increase in activity, respectively. MBaL-30 and -60 agglutinated gram positive Listeria monocytogenes and Staphylococcus aureus, whereas MBaL-30 could merely agglutinate Escherichia coli. None of these lectins could arrest bacterial growth. Addition of MBaL to cancer cell lines (Gastric cancer cell line (AGS) and Gastric cencer cell line (MKN45), Glioblastoma (ECV-304), and Human urinary bladder cancer cell line (U87-MG)) at varying concentrations did not cause statistically significant changes on cell growth and viability.


Assuntos
Momordica/metabolismo , Lectinas de Plantas/análise , Sementes/metabolismo , Sequência de Aminoácidos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Galactose/metabolismo , Testes de Hemaglutinação , Humanos , Peso Molecular , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo
7.
Neurology ; 77(2): 138-44, 2011 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21490322

RESUMO

BACKGROUND: Chronic cerebrospinal venous insufficiency (CCSVI) was recently described in patients with multiple sclerosis (MS). A subject is considered CCSVI positive if ≥ 2 venous hemodynamic (VH) criteria are fulfilled. OBJECTIVE: To determine prevalence of CCSVI in a large cohort of patients with MS, clinically isolated syndrome (CIS), other neurologic diseases (OND), and healthy controls (HC), using specific proposed echo-color Doppler (ECD) criteria. METHODS: Transcranial and extracranial ECD were carried out in 499 enrolled subjects (289 MS, 163 HC, 26 OND, 21 CIS). Prevalence rates for CCSVI were calculated in 3 ways: first, using only the subjects for whom diagnosis was certain (i.e., borderline subjects were excluded); secondly, including the borderline subjects in the "no CCSVI" group; and finally, taking into account subjects who presented any of the VH criteria. RESULTS: CCSVI prevalence with borderline cases included in the "no CCSVI" group was 56.1% in MS, 42.3% in OND, 38.1% in CIS, and 22.7% in HC (p < 0.001). The CCSVI prevalence figures were 62.5% for MS, 45.8% for OND, 42.1% for CIS, and 25.5% for HC when borderline cases were excluded (p < 0.001). The prevalence of one or more positive VH criteria was the highest in MS (81.3%), followed by CIS (76.2%), OND (65.4%), and HC (55.2%) (p < 0.001). CCSVI prevalence was higher in patients with progressive than in nonprogressive MS (p = 0.004). CONCLUSIONS: Our findings are consistent with an increased prevalence of CCSVI in MS but with modest sensitivity/specificity. Our findings point against CCSVI having a primary causative role in the development of MS.


Assuntos
Esclerose Múltipla/epidemiologia , Insuficiência Venosa/epidemiologia , Adulto , Idoso , Doença Crônica , Estudos de Coortes , Estudos Transversais , Avaliação da Deficiência , Ecocardiografia Doppler em Cores/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores , Insuficiência Venosa/diagnóstico
8.
Iran J Immunol ; 6(4): 208-15, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20054109

RESUMO

BACKGROUND: Until now, the comparison of the rK39 strip test (RKT) and direct agglutination test (DAT) for detection of visceral leishmaniasis (VL) is exclusively based on either positive or negative qualification of the reaction outcome. OBJECTIVE: In this study, we compared the diagnostic performance of RKT and DAT for VL both qualitatively and semi-quantitatively. METHODS: For comparison based on semi-quantitative grounds, the execution of RKT and DAT was according to the standard procedures. For comparison on semi-qualitative grounds with DAT, the RKT was applied to aliquots from positive samples that were two-fold serially diluted in saline to determine, as for the DAT, the end-point reaction in RKT. RESULTS: While qualitatively both RKT and DAT demonstrated comparable reliability for VL detection (sensitivity = 96% and specificity = 98.7% or 99.3%), no significant correlation (r = 0.13) could be established between intensities of their positive reactions in 25 cases studied. A negative correlation was further determined in those 25 VL cases between the positive intensities of the RKT and antibody levels measured semi-quantitatively with the same procedure (r = -0.36) or the DAT (r = -0.30). Irrespective of the low, moderate or high antibody levels measured with RKT (< or = 1:8 and 1:16-1:32 > or = 1:256) or DAT (< or = 1:25,600 and 1:51,200- 1:409,600 > or = 1:3,276,800) in patients with confirmed or unconfirmed VL infection, exclusively strong positive intensities were obtained with RKT. CONCLUSION: For further optimizing diagnosis and simultaneously assessing magnitude of immune response to L. donovani infection in Sudanese patients, the combined application of RKT and DAT is recommended.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/imunologia , Testes de Aglutinação , Animais , Anticorpos Antiprotozoários/sangue , Humanos , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Fitas Reagentes/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sudão
9.
Clin Vaccine Immunol ; 14(12): 1592-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17942614

RESUMO

Corroboration of serology results is essential for restricting the risk of inappropriate antileishmanial prescription. A direct agglutination test (DAT) and a recently developed beta-mercaptoethanol-modified enzyme-linked immunosorbent assay (beta-ME ELISA) based on the use of antigen prepared as described for the DAT were applied to 416 sera from two Sudanese populations with and without clinical evidence of visceral leishmaniasis (VL). Of 285 sera with the lowest antileishmanial DAT titers (/=1:25,600), 86 (73.5%) scored maximum (0.81 to >/=1.35) and 30 (25.6%) medium (0.27 to 0.80) beta-ME ELISA absorbance values. VL diagnosis was established for 142 (44.1%) patients in the VL-symptomatic group (n = 322), based on positive microscopy for Leishmania donovani in lymph node aspirates or positive DAT (titer, >/=1:3,200). Of the 125 sera from the symptomatic patients for whom microscopy was positive for VL, 111 (88.8%) had comparable positive DAT and beta-ME ELISA readings. In all 17 sera from the symptomatic DAT-positive patients for whom leishmaniasis was not established by microscopy but who responded favorably to antileishmanial therapy, absorbance values (>/=0.27) indicative of VL were obtained by beta-ME ELISA. Of 197 symptomatic patients for whom microscopy was negative for VL, 172 (87.3%) tested negative in beta-ME ELISA and 180 (91.4%) in DAT. Based on the high reliability demonstrated here for VL detection, beta-ME ELISA fulfills the requirement of confirming DAT results in patients manifesting suspected VL.


Assuntos
Antígenos de Protozoários/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Leishmaniose Visceral/diagnóstico , Mercaptoetanol/farmacologia , Substâncias Redutoras/farmacologia , Testes de Aglutinação , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/química , Estudos de Casos e Controles , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Imunoglobulina G/sangue , Leishmania donovani/citologia , Leishmania donovani/imunologia , Fitas Reagentes , População Rural , Sensibilidade e Especificidade , Estatística como Assunto , Sudão/epidemiologia
11.
J Med Microbiol ; 55(Pt 10): 1343-1347, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17005782

RESUMO

Three-hundred and eight patients with suspected visceral leishmaniasis (VL) were received at Doka Hospital (eastern Sudan) during the period September 2004 to October 2005. The sensitivity and specificity of a glycerol-preserved (GP) antigen for VL diagnosis was assessed against the results of repeated lymph node aspiration and readings from a direct agglutination test (DAT) employing standard formaldehyde-fixed (FF) or freeze-dried (FD) antigen. Despite 13 months of storage at ambient temperature (28-47 degrees C), the GP antigen mean titres obtained from these 308 patients were no different from those that were FD (P=0.945) and stored under similar conditions, but were significantly different (P=0.019) from those that were FF and kept continuously at the optimum temperature for storage (4-8 degrees C). Taking the parasitological result as the gold standard and using a pre-established titre of 1 : 3200 as the DAT cut-off, the GP antigen revealed a sensitivity (91/105, 86.7 %) and specificity (187/203, 92.1 %) comparable to that of FD antigen (92/105, 87.6 %, and 188/203, 92.6 %, respectively) and FF antigen (94/105, 89.5 %, and 188/203, 92.6 %, respectively). At a titre range of 1 : 400-1 : 800, statistically determined as the optimum cut-off for the three antigens, sensitivities of 92.4, 90.5 and 96.2 % and specificities of 90.6, 90.1 and 88.7 % were achieved for the GP, FD and FF antigens, respectively, at a peripheral hospital. Regardless of the antigen preparation used, DAT results obtained in the peripheral hospital were highly reproducible in the central laboratory in Omdurman (weighted kappa: GP=0.957, FD=0.979 and FF=0.936). With a diagnostic reliability comparable to formaldehyde fixation and stability under ambient conditions similar to freeze drying, glycerol preservation, by virtue of its high potential for reproduction, meets the requirements for the management of VL in developing countries.


Assuntos
Antígenos de Protozoários/isolamento & purificação , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Manejo de Espécimes/métodos , Adolescente , Adulto , Testes de Aglutinação/métodos , Animais , Biópsia por Agulha , Criança , Pré-Escolar , Feminino , Glicerol , Hospitais de Condado , Humanos , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/patologia , Linfonodos/imunologia , Linfonodos/patologia , Masculino , Reprodutibilidade dos Testes , População Rural , Sensibilidade e Especificidade , Sudão , Temperatura , Fatores de Tempo
12.
J Med Microbiol ; 55(Pt 9): 1193-1196, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16914648

RESUMO

Following antigen preparation procedures similar to those of the direct agglutination test (DAT), an IgG ELISA employing intact beta-mercaptoethanol (beta-ME)-treated Leishmania donovani promastigotes was developed. The performance of the beta-ME ELISA thus developed was assessed in patients with confirmed visceral leishmaniasis (VL), revealing slightly lower sensitivity (39/40=97.5%) than that of the DAT (40/40=100%). When challenged with sera of individuals with non-VL conditions, including leukaemia and African trypanosomiasis, the specificity of the beta-ME ELISA was 100% (158/158), compared to 98.8% (156/158) for DAT. In an endemic population (n=145) manifesting a clinical suspicion of VL, results obtained with the beta-ME ELISA were highly concordant with those of DAT, both in the seropositive (65/68=95.6%) and seronegative (77/80=96.3%) groups. Furthermore, the incorporated intact antigen demonstrated higher sensitivity in ELISA (16/18=88.9%) than the water-soluble equivalent (13/18=72.2%). The stability of the formaldehyde-fixed antigen (2 months at 4 degrees C) in beta-ME ELISA, as well as the option for direct testing of whole-blood samples and visual reading of results (within 2 h, compared to 18 h for DAT), advocate the simultaneous application of the technique with DAT for confirmation of VL in laboratories with limited facilities.


Assuntos
Antígenos de Protozoários/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Mercaptoetanol/farmacologia , Substâncias Redutoras/farmacologia , Testes de Aglutinação , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/química , Humanos , Imunoglobulina G/sangue , Sensibilidade e Especificidade , Estatística como Assunto
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