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1.
Rev Med Virol ; 29(2): e2024, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30548740

RESUMEN

Respiratory infections, especially those of the lower respiratory tract, remain a foremost cause of mortality and morbidity of children greater than 5 years in developing countries including Pakistan. Ignoring these acute-level infections may lead to complications. Particularly in Pakistan, respiratory infections account for 20% to 30% of all deaths of children. Even though these infections are common, insufficiency of accessible data hinders development of a comprehensive summary of the problem. The purpose of this study was to determine the prevalence rate in various regions of Pakistan and also to recognize the existing viral strains responsible for viral respiratory infections through published data. Respiratory viruses are detected more frequently among rural dwellers in Pakistan. Lower tract infections are found to be more lethal. The associated pathogens comprise respiratory syncytial virus (RSV), human metapneumovirus (HMPV), coronavirus, enterovirus/rhinovirus, influenza virus, parainfluenza virus, adenovirus, and human bocavirus. RSV is more dominant and can be subtyped as RSV-A and RSV-B (BA-9, BA-10, and BA-13). Influenza A (H1N1, H5N1, H3N2, and H1N1pdm09) and Influenza B are common among the Pakistani population. Generally, these strains are detected in a seasonal pattern with a high incidence during spring and winter time. The data presented include pneumonia, bronchiolitis, and influenza. This paper aims to emphasise the need for standard methods to record the incidence and etiology of associated pathogens in order to provide effective treatment against viral infections of the respiratory tract and to reduce death rates.


Asunto(s)
Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/etiología , Virosis/epidemiología , Virosis/etiología , Virus/clasificación , Virus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Pakistán/epidemiología , Prevalencia , Infecciones del Sistema Respiratorio/patología , Topografía Médica , Virosis/patología , Adulto Joven
2.
J Med Virol ; 91(11): 1909-1917, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31273791

RESUMEN

Dengue viral infection has become a challenge in tropical and subtropical countries where dengue virus is endemic. Its epidemics are occurring at higher rates amid its circulation throughout the year. Since the first documented outbreak in Pakistan in 1994, this region has reported many sporadic cases and epidemics. There is availability of small scale demographic and epidemiological studies on dengue viral infection in Pakistan. The year 2017 witnessed a huge dengue outbreak in Peshawar city of Pakistan with 69 deaths and 24 807 laboratory-confirmed cases. We suspect that the circulation of a different lineage or genotype could be responsible for the enhanced number of infected patients in Pakistan's 2017 outbreak since previous studies have already described this phenomenon in other countries. For this, we collected 1447 suspected blood samples and their epidemiological data. After serotyping through polymerase chain reaction nine samples of Dengue virus2 (DENV2) were randomly selected and were subjected to Sanger's sequencing for genotyping analysis. The mean distance, genetic diversity, and phylogenetic analysis were carried out using K2 model. The phylogenetic analysis split Pakistani isolates into two lineages, the sequences from 2017 outbreak in Peshawar grouped within A1 lineage of cosmopolitan genotype (IV) of DENV2. The difference in distance, genetic diversity, and amino acids composition strongly back the results that the new lineage is circulating in the region. This is significant as Pakistan is struggling to control dengue epidemics which have caused much loss in both monetary and health sectors.


Asunto(s)
Virus del Dengue/genética , Dengue/epidemiología , Dengue/virología , Brotes de Enfermedades/estadística & datos numéricos , Adolescente , Adulto , Anticuerpos Antivirales/sangre , Dengue/sangre , Virus del Dengue/inmunología , Femenino , Variación Genética , Genotipo , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Pakistán/epidemiología , Filogenia , ARN Viral/genética , Serogrupo , Adulto Joven
3.
Pak J Pharm Sci ; 32(5): 1957-1964, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31813858

RESUMEN

The present study comprises the synthesis of a new series of benzenesulfonamides derived from N-sulfonation of 2-(4-methoxyphenyl)-1-ethanamine (1). The synthesis was initiated by the reaction of 2-(4-methoxyphenyl)-1-ethanamine (1) with benzenesulfonyl chloride (2), to yield N-(4-methoxyphenethyl)benzenesulfonamide (3). This parent molecule 3 was subsequently treated with various alkyl/aralkyl halides (4a-j) in N,N-dimethylformamide (DMF) and in the presence of a weak base lithium hydride (LiH) to obtain various N-(alkyl/aralkyl)-N-(4-methoxyphenethyl) benzenesulfonamides (5a-j). The characterization of these derivatives was carried out by spectroscopic techniques like IR, 1H-NMR, and 13C-NMR. Elemental analysis also supported this data. The biofilm inhibitory action of all the synthesized compounds was carried out on Escherichia coli and some of the compounds were identified to be very suitable inhibitors of this bacterial strain. Furthermore, the molecules were also tested for their cytotoxicity behavior to assess their utility as less cytotoxic therapeutic agents.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Sulfonamidas/síntesis química , Sulfonamidas/farmacología , Biopelículas/efectos de los fármacos , Relación Estructura-Actividad , Sulfonamidas/química , Bencenosulfonamidas
4.
Virol J ; 12: 148, 2015 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-26395339

RESUMEN

BACKGROUND: Pattern of Dengue periodic epidemics through the years along with sporadic cases of Dengue hemorrhagic fever followed by a severe 2011 epidemic of Dengue fever in Pakistan make Pakistan a Dengue endemic country. To study the entry and evolution of dengue virus serotype 2 (DENV-2) in Pakistan, we sequenced three full length genomes and 24 complete envelope sequences of DENV-2 from the years 2010, 2011 and 2013 collected from Punjab province of Pakistan. METHODS: Phylogenetic and Bayesian phylogeographic analyses was applied to three full genome sequences as well as 24 envelope sequences to study the spatiotemporal dynamics of DENV-2 in Pakistan. RESULTS: Most of the DENV-2 viruses from the years 2008 to 2013 formed a monophyletic Pakistani clade in IVb sublineage of cosmopolitan genotype except one 2008 DENV-2 strain. Phylogeographic analysis revealed that this 2008 DENV-2 strain was rooted to India 25.4 years ago with a location probability of 0.88. However Pakistani clade rooted back to Sri Lanka 12.6 years ago with a location probability of 0.57. CONCLUSION: DENV-2 genotype IV was introduced in Pakistan in two time events. First event was introduction from India to Pakistan in the late 1980s (around 1986), and second event was introduction from Sri Lanka to Pakistan around 2000. The later introduction event was responsible for major outbreaks in the Punjab region of Pakistan, including major 2011 outbreak. After the second Introduction event, DENV-2 circulated locally in the region forming a distinct Sublineage within the IVb cosmopolitan genotype of DENV-2.


Asunto(s)
Virus del Dengue/clasificación , Virus del Dengue/genética , Dengue/virología , Brotes de Enfermedades , Filogeografía , Análisis por Conglomerados , Dengue/epidemiología , Virus del Dengue/aislamiento & purificación , Evolución Molecular , Genoma Viral , Humanos , India , Datos de Secuencia Molecular , Pakistán , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Sri Lanka/epidemiología
5.
Singapore Dent J ; 35: 47-52, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25496585

RESUMEN

BACKGROUND: Instrumentation of the root surface, results in formation of a smear layer of organic and mineralized debris which serves as a physical barrier, inhibiting new connective tissue attachment to the root surface. The present study advocates the use of an endodontic irrigant MTAD (mixture of tetracycline, citric acid and detergent) as a root conditioning agent. The main aim of the study was to compare the root conditioning ability of an endodontic irrigant MTAD (mixture of tetracycline, acid and detergent) with 17% EDTA (ethylenediaminetetraacetic acid). MATERIALS AND METHODS: Sixty freshly extracted human single rooted teeth with confirmed periodontal involvement were selected for this study and decoronated. The apical third of each root was removed and the remaining root was sectioned longitudinally to produce a 6mm to 8mm long tooth section. The root surface was then instrumented by hand using a sharp Gracey 1-2 periodontal curette with 6-8 strokes per area to achieve a smooth glass-like surface. A total of 60 specimens were prepared which were randomly divided into three groups (n=20). Each group received the root conditioning treatments as follows: All specimens were prepared for SEM and scored according to the presence of smear layer. RESULTS AND CONCLUSIONS: MTAD removed the smear layer successfully from the root surfaces. The mean smear score for samples treated with Biopure MTAD was lower than those treated with EDTA, (p=0.04). MTAD can be used as a root conditioning agent with efficient smear layer removal ability and known antimicrobial and anticollagenase activity.

6.
Eur Radiol ; 23(8): 2258-63, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23519438

RESUMEN

OBJECTIVES: The purposes of this MR-based study were to calculate q-space imaging (QSI)-derived mean displacement (MDP) in meningiomas, to evaluate the correlation of MDP values with apparent diffusion coefficient (ADC) and to investigate the relationships among these diffusion parameters, tumour cell count (TCC) and MIB-1 labelling index (LI). METHODS: MRI, including QSI and conventional diffusion-weighted imaging (DWI), was performed in 44 meningioma patients (52 lesions). ADC and MDP maps were acquired from post-processing of the data. Quantitative analyses of these maps were performed by applying regions of interest. Pearson correlation coefficients were calculated for ADC and MDP in all lesions and for ADC and TCC, MDP and TCC, ADC and MIB-1 LI, and MDP and MIB-1 LI in 17 patients who underwent subsequent surgery. RESULTS: ADC and MDP values were found to have a strong correlation: r = 0.78 (P = <0.0001). Both ADC and MDP values had a significant negative association with TCC: r = -0.53 (p = 0.02) and -0.48 (P = 0.04), respectively. MIB-1 LI was not, however, found to have a significant association with these diffusion parameters. CONCLUSION: In meningiomas, both ADC and MDP may be representative of cell density. KEY POINTS: • Diffusion-weighted MRI offers possibilities to assess the aggressiveness of meningiomas. • The q-space imaging-derived mean displacement correlates strongly with apparent diffusion coefficients. • Both diffusion parameters showed a strong negative association with tumour cell counts. • Derived mean displacement may help assess the aggressiveness of meningiomas preoperatively.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias Meníngeas/patología , Meningioma/patología , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador
7.
Neuroradiology ; 55(3): 253-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23053002

RESUMEN

INTRODUCTION: To assess and compare age-related diffusion changes in the white matter in different cerebral lobes, as quantified by diffusion-weighted imaging (DWI) and high b-value q-space imaging (QSI). METHODS: Seventy-three cases without neurological symptoms or imaging abnormalities were grouped by age as young (<30 years, n = 20), middle-aged (30-49 years, n = 19), old (50-69 years, n = 18), and very old (> 70 years, n = 16) and imaged by a 1.5-T MR scanner for DWI and QSI. Apparent diffusion coefficient (ADC) and mean displacement (MDP) values were calculated in the white matter of frontal, parietal, and temporal lobes and compared using Dunnett's test, with the young group as a control. RESULTS: MDP values in frontal and parietal lobes were significantly higher in old and very old age groups than in the young, while those in the temporal lobes were significantly higher only in the very old group. ADC values were significantly higher in all three lobes in the very old group. CONCLUSION: QSI is more sensitive than DWI to age-related myelin loss in white matter.


Asunto(s)
Envejecimiento/patología , Algoritmos , Corteza Cerebral/citología , Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos , Fibras Nerviosas Mielínicas/ultraestructura , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
8.
Can Assoc Radiol J ; 64(1): 51-5, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22397827

RESUMEN

PURPOSE: To evaluate imaging characteristics of optic nerves by using magnetic resonance imaging, especially diffusion-weighted imaging (DWI) with apparent diffusion coefficient measurements in acute and chronic phases of optic neuritis (ON). MATERIALS AND METHODS: A retrospective study was conducted by using records of 14 patients with clinically suspected acute ON (15 nerves), 5 chronic ON (7 nerves), and 11 normal volunteers with no eye symptoms were used as controls. Magnetic resonance imaging was performed by a 1.5T scanner. Affected nerves were evaluated for sizes, signal characteristics on DWI and T2-weighted imaging (T2WI), contrast enhancement, and apparent diffusion coefficient values. Visually assessed characteristics were compared between the acute and chronic, whereas apparent diffusion coefficient values were assessed among acute ON, chronic ON, and the control groups by using the Fisher exact test and Mann-Whitney U test. RESULTS: There were significant differences in the diameter of the optic nerves, hyperintensity on DWI, and enhancement characteristics on post-enhanced images in acute and chronic phases of ON (P = .0001, P < .0001, and P = .0022, respectively), apparent diffusion coefficient values of the optic nerves in acute ON, chronic ON, and control groups also differed significantly from each other. CONCLUSION: In conclusion, DWI can add valuable information in assessment of damage to nerve and neuronal barriers and thus in predicting recovery in cases of ON.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Neuritis Óptica/diagnóstico , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no Paramétricas
9.
J Ayub Med Coll Abbottabad ; 35(1): 110-113, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36849388

RESUMEN

BACKGROUND: Hepatitis C is a diverse illness that causes significant death and morbidity. The hepatitis C virus infects hundreds of millions of individuals globally (HCV). More than 80% of those infected develop chronic infection; the remaining 10-20% recovers spontaneously through natural immunity. Acute hepatitis is only icteric in 20% of individuals and is seldom severe. METHODS: A pilot study was conducted at INOR hospital Abbottabad. Eleven hepatitis C positive and 10 hepatitis C negative participants were included in the study. RESULTS: A significant difference correlation was found between viral load and SWE quantification for fibrosis stage in Kilo-Pascal, r=0.904 (p-value=0.000

Asunto(s)
Hepatitis C , Humanos , Proyectos Piloto , Carga Viral , Hepacivirus , Fibrosis
10.
Medicine (Baltimore) ; 102(2): e32651, 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36637937

RESUMEN

High-risk-human papillomavirus (HR-HPV)-induced cervical cancer is the second most common cause of death among females worldwide. HPV16 is the most prevalent HR-HPV infection worldwide. This study found the genotypic distribution of HR-HPV in the local population and investigated the sequence variations among the E6 and E7 oncogenes of the local HPV16 genotype to the E6 and E7 oncogenes of the foreign HPV16 genotypes and constructed a phylogenetic relationship based on nucleotide sequence comparison among the variants identified in our study along with previously reported isolates that were obtained from different regions of the world. The samples were collected from patients with cervical cancer. Genomic DNA was extracted, and HR-HPV genotypes were determined using real-time PCR. The HPV16 E6 and E7 genes were amplified and sequenced. A HPV16 phylogenetic tree was constructed using the maximum likelihood method with MEGA 7. HPV16 was the most prevalent human papillomavirus (HPV) type identified in the present study. HPV16 isolates belonged to the A1 sublineage of the European branch. Twenty-one nucleotide sequences were included in this analysis. The first, second, and third codon positions are also included. The final dataset included 776 positions.


Asunto(s)
Virus del Papiloma Humano , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Genotipo , Papillomavirus Humano 16/genética , Virus del Papiloma Humano/genética , Proteínas Oncogénicas Virales/genética , Pakistán/epidemiología , Proteínas E7 de Papillomavirus/genética , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Filogenia
11.
J Magn Reson Imaging ; 35(4): 827-36, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22069025

RESUMEN

PURPOSE: To differentiate mass-forming autoimmune pancreatitis (AIP) from pancreatic carcinoma by means of analysis of both computed tomography (CT) and magnetic resonance imaging (MRI) findings. MATERIALS AND METHODS: Ten patients with mass-forming AIP diagnosed by revised clinical criteria of Japan Pancreas Society and 70 patients with pathologically proven pancreatic carcinoma were enrolled in this retrospective study. Two radiologists independently evaluated the CT and MR imaging findings. The sensitivity, specificity, and odds ratio of significant imaging findings and combinations of findings were calculated. RESULTS: Seven findings were more frequently observed in AIP patients: (i) early homogeneous good enhancement, (ii) delayed homogeneous good enhancement, (iii) hypoattenuating capsule-like rim, (iv) absence of distal pancreatic atrophy, (v5) duct penetrating sign, (vi) main pancreatic duct (MPD) upstream dilatation ≤ 4 mm, and (vii) an apparent diffusion coefficient (ADC) ≤ 0.88 × 10(-3) mm(2) /s. When the findings of delayed homogeneous enhancement and ADC ≤ 0.88 × 10(-3) mm(2) /s were both used in diagnosis of mass-forming AIP, a sensitivity of 100% and a specificity of 100% were achieved. When 4 of any of the 7 findings were used in the diagnosis of AIP, a sensitivity of 100% and a specificity of 98% were achieved. CONCLUSION: Analysis of a combination of CT and MR imaging findings allows for highly accurate differentiation between mass-forming AIP and pancreatic carcinoma.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico , Pancreatocolangiografía por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Pancreáticas/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
BMC Microbiol ; 11: 200, 2011 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-21906394

RESUMEN

BACKGROUND: Since the first reported outbreak of dengue hemorrhagic fever in Pakistan, several mini outbreaks have erupted in the region. Dengue virus serotype 3 (DEN-3) was first documented in 2005 outbreak in Karachi. Reports show that serotype 3 is prevalent in Lahore since 2008. Serotype 2 (DEN-2) is the major circulating serotype in Pakistan as it is documented since 1994. We have conducted a detailed study of three outbreaks of dengue virus infection that occurred in years 2007, 2008 and 2009 in Lahore by using molecular techniques such as PCR and nucleotide sequencing of the C-prM gene junction of Dengue virus. RESULTS: Through the analysis of 114 serum samples collected over the period of three years (2007-2009), total 20 patients were found to be infected with dengue virus. In year 2007, four were positive for serotype 2 and one sample was positive for serotype DEN-3. In 2008, five samples had concurrent infection with serotypes DEN-2 and DEN-3 while three samples were infected only with serotype DEN-2. In year 2009, one sample had concurrent infection with serotypes DEN-2 and DEN-3 while six were positive for serotype DEN-2 only. CONCLUSIONS: Our study showed that serotype DEN-2 was dominant in positive samples of dengue virus infection collected during the period of three years (2007-2009). The other serotype present was serotype DEN-3. Genotypes of serotype DEN-2 and serotype DEN-3 were subtype IV and subtype III, respectively.


Asunto(s)
Virus del Dengue/clasificación , Virus del Dengue/aislamiento & purificación , Filogenia , Dengue Grave/epidemiología , Dengue Grave/virología , Técnicas de Tipificación Bacteriana , Virus del Dengue/genética , Brotes de Enfermedades , Genotipo , Humanos , Datos de Secuencia Molecular , Pakistán/epidemiología , Reacción en Cadena de la Polimerasa , Serotipificación , Proteínas Virales/genética
13.
J Magn Reson Imaging ; 34(2): 326-35, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21780227

RESUMEN

PURPOSE: To compare the diagnostic accuracy of contrast-enhanced computed tomography (CE-CT), contrast-enhanced ultrasonography (CE-US), superparamagnetic iron oxide-enhanced magnetic resonance imaging (SPIO-MRI), and gadoxetic acid-enhanced MRI (Gd-EOB-MRI) in the evaluation of colorectal hepatic metastases. MATERIALS AND METHODS: In all, 111 patients with colorectal cancers were enrolled in this study. Of the 112 metastases identified in 46 patients, 31 in 18 patients were confirmed histologically and the remaining 81 in 28 patients were confirmed by follow-up imaging. CE-CT, CE-US, SPIO-MRI, and Gd-EOB-MRI were evaluated. Mean (of three readers, except for CE-US) area under the receiver operating characteristic curve (A(z) ), sensitivities, and positive predictive values (PPV) were calculated. Each value was compared to the others by variance z-test or chi-square test with Bonferroni correction. RESULTS: For all lesions, mean A(z) and sensitivity of Gd-EOB-MRI (0.992, 95% [56/59]) were significantly greater than those of CE-CT (0.847, 63% [71/112]) and CE-US (0.844, 73% [77/106]). For lesions ≤1 cm, mean A(z) and sensitivity of Gd-EOB-MRI (0.999, 92% [22/24]) were significantly greater than those of CE-CT (0.685, 26% [13/50]) and CE-US (0.7, 41% [18/44]). Mean A(z) (95% CI) of SPIO-MRI for all lesions (0.966 [0.929-0.987]) and lesions ≤ 1 cm (0.961 [0.911-0.988]) were significantly greater than those of CE-CT and CE-US. Mean sensitivity of SPIO-MRI for lesions ≤1 cm (63%, 26/41) was significantly greater than that of CE-CT. CONCLUSION: Gd-EOB-MRI and SPIO-MRI were more accurate than CE-CT and CE-US for evaluation of liver metastasis in patients with colorectal carcinoma.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Medios de Contraste/farmacología , Compuestos Férricos/farmacología , Gadolinio DTPA/farmacología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC
14.
Acta Radiol ; 52(10): 1155-8, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22067205

RESUMEN

BACKGROUND: Q-space analysis is a new metric that uses multiple, high b-value, diffusion-weighted magnetic resonance (MR) data. This technique shows promising results as a tool to provide information complementary to that of other imaging techniques used on biological tissue in vivo. PURPOSE: To investigate the use of a mean displacement (MDP) map of high b-value, q-space imaging (QSI) to characterize spinal and spinal cord lesions in vivo. MATERIAL AND METHODS: Eight patients with spine or spinal cord disorders (two neurinomas, one myeloma, three cases of syringohydromyelia, and two cases of cervical spondylosis) were included. The MR imaging protocol consisted of conventional MR sequences, conventional diffusion-weighted imaging (DWI; b = 1000), and high b-value QSI with a maximum q value of 836.9 cm(-1). Apparent diffusion coefficient (ADC) maps of conventional DWI and MDP maps of QSI data were obtained and region-of-interest analyses for the lesions were performed. RESULTS: MDP values of normal spinal cord, cerebrospinal fluid (CSF), and tumor parenchyma were 6.57 ± 0.52, 17.6 ± 2.75, and 8.49 ± 2.09, respectively (µm, mean ± standard deviation). In general, MDP maps were not well correlated with the corresponding ADC maps at the pathologic lesions. Spondylotic lesions tended to have higher MDP values than normal spinal cord, whereas syringohydromyelia produced MDP values slightly lower than those of CSF. CONCLUSION: The heterogeneous MDP values were probably due to differences in tissues and pathologic structures. This technique has potential to provide additional clinical information to that obtained with conventional MR imaging.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Aumento de la Imagen/métodos , Enfermedades de la Médula Espinal/patología , Enfermedades de la Columna Vertebral/patología , Estudios de Factibilidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Médula Espinal/patología , Columna Vertebral/patología
15.
Virol J ; 7: 377, 2010 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-21194456

RESUMEN

Hepatitis C is a major health problem affecting more than 200 million individuals in the world. Current treatment regimen consisting of interferon alpha and ribavirin does not always succeed in eliminating the virus completely from patient's body. One of the mechanisms by which virus evades the antiviral effect of interferon alpha involves protein kinase (PKR) eukaryotic initiation factor 2 alpha (eIF2a) phosphorylation homology domain (PePHD). This domain in genotype 1 strains is reportedly homologous to PKR and its target eIF2a. By binding to PKR, PePHD inhibits its activity and therefore cause virus to evade antiviral activity of interferon (IFN). Many studies have correlated substitutions in this domain to the treatment response and lead to inconclusive results. Some studies suggested that substitutions favor response while others emphasized that no correlation exists. In the present study we therefore compared sequences of PePHD domain of thirty one variants of six hepatitis C virus patients of genotype 3. Three of our HCV 3a infected patients showed rapid virological response to interferon alpha and ribavirin combination therapy whereas the remaining three had breakthrough to the same combination therapy. It is found that PePHD domain is not entirely conserved and has substitutions in some isolates irrespective of the treatment response. However substitution of glutamine (Q) with Leucine (L) in one of the breakthrough responders made it more identical to HCV genotype 1a. These substitutions in the breakthrough responders also tended to increase average hydrophilic activity thus making binding of PePHD to PKR and inhibition of PKR more favorable.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Hepatitis C/virología , Interferones/uso terapéutico , Ribavirina/uso terapéutico , Proteínas del Envoltorio Viral/genética , Secuencia de Aminoácidos , Quimioterapia Combinada , Factor 2 Eucariótico de Iniciación/genética , Genotipo , Humanos , Mutación/genética , Pakistán , Estructura Terciaria de Proteína , Alineación de Secuencia , Proteínas del Envoltorio Viral/química
16.
Virol J ; 7: 296, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21040548

RESUMEN

Hepatitis C virus (HCV) is a member of Flaviviridae family and one of the major causes of liver disease. There are about 175 million HCV infected patients worldwide that constitute 3% of world's population. The main route of HCV transmission is parental however 90% intravenous drug users are at highest risk. Standard interferon and ribavirin remained a gold standard of chronic HCV treatment having 38-43% sustained virological response rates. Currently the standard therapy for HCV is pegylated interferon (PEG-INF) with ribavirin. This therapy achieves 50% sustained virological response (SVR) for genotype 1 and 80% for genotype 2 & 3. As pegylated interferon is expensive, standard interferon is still the main therapy for HCV treatment in under developed countries. On the other hand, studies showed that pegylated IFN and RBV therapy has severe side effects like hematological complications. Herbal medicines (laccase, proanthocyandin, Rhodiola kirilowii) are also being in use as a natural and alternative way for treatment of HCV but there is not a single significant report documented yet. Best SVR indicators are genotype 3 and 2, < 0.2 million IU/mL pretreatment viral load, rapid virological response (RVR) rate and age <40 years. New therapeutic approaches are under study like interferon related systems, modified forms of ribavirin, internal ribosome entry site (HCV IRES) inhibitors, NS3 and NS5a inhibitors, novel immunomodulators and specifically targeted anti-viral therapy for hepatitis C compounds. More remedial therapies include caspase inhibitors, anti-fibrotic agents, antibody treatment and vaccines.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Antivirales/efectos adversos , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Quimioterapia Combinada/tendencias , Hepatitis C/epidemiología , Humanos , Interferón alfa-2 , Interferón-alfa/efectos adversos , Polietilenglicoles/efectos adversos , Proteínas Recombinantes , Ribavirina/efectos adversos , Resultado del Tratamiento
17.
Childs Nerv Syst ; 26(8): 1121-4, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20437241

RESUMEN

INTRODUCTION: Evaluation of the congenital vascular lesions of the brain requires multiple conventional intra-arterial digital subtraction angiographic examinations which have many associated risks including exposure to ionizing radiations. Magnetic resonance digital subtraction angiography is a non-invasive procedure with no related risks of radiation exposure. This technique can be of greater clinical significance in diagnosis and treatment planning of neurovascular abnormalities among children who are at far greater risk of invasive procedures like intra-arterial digital subtraction angiography. CASE REPORT: We report a congenital pial arteriovenous fistula in an infant which is a rare vascular lesion and has recently been identified as different from other vascular malformations. Magnetic resonance digital subtraction angiography provided hemodynamic information in absolute agreement with intra-arterial digital subtraction angiography indicating its significance in evaluating vascular lesions. DISCUSSION: Magnetic resonance digital subtraction angiography can be used in children in conjunction with intra-arterial digital subtraction angiography to minimize the cumulative radiation dose and multiple anesthesias.


Asunto(s)
Angiografía de Substracción Digital , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Piamadre/diagnóstico por imagen , Medios de Contraste , Femenino , Humanos , Recién Nacido , Piamadre/anomalías
18.
Viral Immunol ; 32(8): 335-340, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31553269

RESUMEN

Hepatitis delta virus (HDV) is a highly pathogenic virus and causes rapid disease progression from fulminant hepatitis to development of hepatocellular carcinoma in patients infected with hepatitis B virus (HBV). HDV is endemic in Pakistan; however, there are no available data on HDV prevalence among the high-risk group of HBV-infected pregnant women. A total of 1,394 pregnant women, visiting different public-sector hospitals in Lahore, were enrolled in this study. Their demographic data and blood samples were collected from May 2016 to July 2017. Samples were screened for both HBsAg and anti-HDV. Anti-HDV positive samples were tested for HDV RNA, and samples positive for HDV RNA were further sequenced to determine the HDV genotype. Of the 1,394 samples, HBsAg was positive in 63 (4.5%). Of these 63 HBsAg-positive samples, 13 (20.63%) were positive for anti-HDV. Of the 13 HBsAg/anti-HDV positive samples, HDV RNA was detected in 4 (30.8%) samples and all 4 carried HDV genotype 1. The age of enrolled women varied from 20 to 40 years, with most of the women living in urban areas, having education more than secondary school level, belonging to middle class, and being housewives. Majority of the tested women were of age from 25 to 30 years (39.2%); however, the prevalence of HBV was higher in age group 31-35 years (10.7%, confidence interval [CI]: 4.73-16.67); however, anti-HDV prevalence was 1.9% (CI: -0.7 to 4.7). This study is the first report on HDV prevalence among pregnant women in Pakistan. Our study showed a high predominance of HDV (20.63%) in HBV-infected pregnant women and the prevalence of HDV genotype 1 infection. The findings contribute to a better understanding of the HDV/HBV coinfection among pregnant women and circulating HDV genotypes in the country.


Asunto(s)
Coinfección/epidemiología , Hepatitis B/epidemiología , Hepatitis D/epidemiología , Hepatitis D/virología , Virus de la Hepatitis Delta/aislamiento & purificación , Adulto , Anticuerpos Antivirales/sangre , Coinfección/virología , Femenino , Genotipo , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis Delta/clasificación , Virus de la Hepatitis Delta/genética , Virus de la Hepatitis Delta/inmunología , Humanos , Pakistán/epidemiología , Filogenia , Embarazo , Prevalencia , ARN Viral/sangre , ARN Viral/genética , Adulto Joven
20.
J Clin Virol ; 108: 26-31, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30219747

RESUMEN

BACKGROUND: In Pakistan, HCV disease is considered a major public health issue with about 10-17 million people suffering with this infection and rate is increasing every day without any hindrance. The currently available Pyrosequencing approach used to analyze complex viral genomes as it can determine minor variants. It is crucial to understand viral evolution and quasispecies diversity in complex viral strains. OBJECTIVES: To assess genetic diversity in patients with HCV using Next Generation Sequencing (NGS) and compare nucleotide diversity of genotype 3a with respect to other genotypes. STUDY DESIGN: Intra-host viral diversity of HCV was determined using NGS from 13 chronically HCV infected individuals. NGS of three different regions (E2 (HVR1), NS3 and NS5B) of HCV-3a allowed for a comprehensive analysis of the viral population. RESULT: Phylogenetic analysis of different HCV genes revealed great variability within the Pakistani population. The average nucleotide diversity for HVR1, NS3 and NS5B was 0.029, 0.011 and 0.010 respectively. CONCLUSION: Our findings clearly indicate that patient-2 greater quasispecies heterogeneity than other patients of same genotype-3a using phylogenetic and one step network analyses. Initially phylogenetic analysis of these three genes showed that genotype 3a samples have greater genetic diversity. However, no significant difference was determined when nucleotide variability of genotype 3a compared with other genotypes (1a, 1b, 2a & 4a).


Asunto(s)
Variación Genética , Genoma Viral , Genotipo , Hepacivirus/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Hepatitis C/epidemiología , Humanos , Pakistán/epidemiología , Filogenia , Análisis de Secuencia de ADN
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