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1.
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
2.
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
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.
Lancet Infect Dis ; 19(12): 1287-1288, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31782395
5.
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
6.
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
7.
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
8.
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
9.
Viral Immunol ; 30(10): 734-736, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28949818

RESUMEN

Over the years, dengue fever has become a significant infectious disease in different parts of the world. Medical and public health services have been unable to deal with infection as there is no vaccine available for the prevention of this infection. With dengue, effective treatments are not available due to which severe symptoms may develop. To deal with this challenge, a sensitive and specific technique is required for its early diagnosis along with the knowledge of dengue serotype to increase the specificity of diagnosis and treatment. This study was designed to check the usefulness of immunological and nucleic acid-based molecular determination of dengue virus. The study recommends polymerase chain reaction as a suitable method for the rapid detection of dengue virus as it was found more sensitive than other utilized techniques, including antibodies detection. Nucleic acid analysis may also help to define the common serotypes/genotypes of dengue virus circulating in any region.


Asunto(s)
Virus del Dengue/genética , Dengue/diagnóstico , ARN Viral/genética , Anticuerpos Antivirales/sangre , Antígenos Virales/sangre , Dengue/sangre , Dengue/epidemiología , Dengue/virología , Virus del Dengue/clasificación , Diagnóstico Precoz , Femenino , Humanos , Masculino , Pakistán/epidemiología , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , Sensibilidad y Especificidad
10.
J Dig Dis ; 18(7): 404-409, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28608576

RESUMEN

OBJECTIVE: The study was aimed to evaluate the specificity, cost and turnaround time of three different techniques that can be used for analyzing the single nucleotide polymorphism of interleukin 28B (IL28B) rs129796860. METHODS: DNA from peripheral blood samples of 111 patients with chronic hepatitis C were genotyped using three types of genotyping methods: direct sequencing, SNaPshot polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Three distinct profiles for IL28B rs12979860 alleles (CC, CT and TT) were obtained with direct sequencing, SNaPshot PCR and PCR-RFLP and the results were consistent among all three methods. CONCLUSION: For routine medical practice, screening IL28B rs12979860 can be performed by PCR-RFLP, which is efficient and reliable as well as cost-effective.


Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Interleucinas/genética , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Nucleótido Simple , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , Técnicas de Genotipaje , Humanos , Interferones , Polimorfismo de Longitud del Fragmento de Restricción , Pronóstico , Resultado del Tratamiento
11.
Viral Immunol ; 30(5): 366-370, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28346804

RESUMEN

Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major cause of the global burden of hepatitis. One of the main routes of transmission for both viruses is through exposure to infected blood, which includes sharing blood-contaminated syringes and needles. Human immunodeficiency virus (HIV) attacks the immune system and results in acquired immune deficiency syndrome and opportunistic infections. The objective of this study was to assess the epidemiology of HBV and HCV infections among HIV-infected people who inject drugs (PWID). The study enrolled 100 PWID from different addiction centers of the city of Lahore in Pakistan. All subjects were HIV-infected males and were above 16 years of age. Screening of HBV and HCV infections was performed through immunochromatography tests and enzyme-linked immunosorbent assays. The prevalence of HCV and HBV infections among the 100 HIV-infected PWID was 55% and 6%, respectively. HIV monoinfection was found in 37% of the subjects, while triple infection was detected in 2% of the subjects. Majority of the HIV-infected PWID were using heroin and Avil injections (65%). Half of the subjects had used injection drugs for 1-5 years, while 32% had used injection drugs for 6-10 years. HCV infection was more common than HBV infection among the enrolled subjects. Most of the PWID were practicing heroin and Avil injections.


Asunto(s)
Coinfección/epidemiología , Infecciones por VIH/complicaciones , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adolescente , Adulto , Cromatografía de Afinidad , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Persona de Mediana Edad , Pakistán/epidemiología , Prevalencia , Adulto Joven
12.
Viral Immunol ; 30(1): 20-27, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27830995

RESUMEN

Viruses are the intracellular pathogens that reproduce only in the living cell and manipulate the cellular machinery to produce more viruses. Viral replications can affect cellular genes of the host in multiple cancerous ways. Approximately, 20% of all human oncogenesis is caused by cancer-causing viruses known as oncoviruses. Viral infection causes chronic inflammation leading to cell death, uncontrollable proliferation, and modulated expression of some of the regulatory proteins. Oncogenesis is a multistep phenomenon in which normal host cells are transformed into cancerous cells on the basis of host genetic variability. Oncogenic viruses encode genes that cause viral replication and transformation of the host cells to produce viral proteins and protein complexes. The phenomenon from basic viral infection to tumorigenesis is lengthy due to the involvement of factors like immunity complications, cellular mutations, and exposure to other cancerous agents. The viruses that are involved in human cancer development are Hepatitis B virus (HBV), Hepatitis C virus (HCV), Epstein-Barr virus (EBV), Human papilloma virus (HPV), Kaposi's sarcoma herpes virus (KSHV), and Human T lymphotrophic virus 1 (HTLV-1). This review article summarizes advanced knowledge related to human oncogenic viruses and the molecular mechanisms that lead to tumorigenesis in humans.


Asunto(s)
Carcinogénesis , Transformación Celular Neoplásica , Interacciones Huésped-Patógeno , Neoplasias/fisiopatología , Neoplasias/virología , Virus Oncogénicos/patogenicidad , Humanos
13.
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
14.
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.

16.
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
17.
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
18.
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
19.
Hepatol Int ; 7(2): 662-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26201799

RESUMEN

PURPOSE: The effectiveness of imaging (including apparent diffusion coefficient [ADC] of diffusion-weighted magnetic resonance imaging [DWI]) and laboratory variables for predicting early tumor recurrence and overall survival after surgery in hepatocellular carcinoma (HCC) patients are analyzed. METHODS: The present study included 116 consecutive patients with HCC who underwent partial hepatectomy. Patients were classified into two groups: patients with and without early recurrence (<1 year). Preoperative imaging variables (tumor number, size, shape, capsule, ADC, and venous invasion) and laboratory variables were evaluated to predict early recurrence using univariate and multivariate analyses. Overall survival was calculated using the Kaplan-Meier method. RESULTS: Twenty patients (17 %) developed early recurrence after surgery. Multivariate logistic regression analysis showed that tumor ADC (p = 0.0002), aspartate aminotransferase (p = 0.0121), and serum prothrombin time activity percentage (p = 0.0082) were statistically significant for predicting early recurrence. The optimal ADC cutoff value for predicting early recurrence obtained from receiver operating characteristic analysis was ≤0.898 × 10(-3) mm(2)/s. In patients with ADC ≤0.898 × 10(-3) mm(2)/s, the 3- and 5-year survival rates (77 and 56 %, respectively) were significantly decreased compared with those in patients with ADC >0.898 × 10(-3) mm(2)/s (97 and 97 %, respectively; p = 0.0015). CONCLUSIONS: Low tumor ADC value by DWI was a risk factor for early postoperative HCC recurrence and was associated with lower patient survival rates.

20.
Acad Radiol ; 19(11): 1362-7, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22906594

RESUMEN

RATIONALE AND OBJECTIVES: The purpose of this study was to determine the effectiveness of combining basi-parallel anatomic scanning (BPAS)-magnetic resonance (MR) imaging findings with those of time-of-flight (TOF)-MR angiography (MRA) for differentiating vertebral artery dissection (VAD) from other causes of true artery narrowing such as atherosclerosis or an anatomical variation such as vertebral artery hypoplasia. MATERIALS AND METHODS: Fifteen cases of VAD, 15 of atherosclerotic narrowing, and 8 of hypoplastic vertebral arteries were retrospectively selected for this study. Conventional MR sequences (T1WI, T2WI, and T2*WI, fluid attenuation inversion recovery, TOF-MRA) and BPAS images were analyzed by two readers blinded to the patients' clinical data and history. Receiver operating characteristic analyses were performed to compare the diagnostic capability of conventional MR sequences with and without BPAS imaging in suspected VAD cases. RESULTS: The area under the curve increased significantly by combining BPAS imaging findings with those of conventional MRI (0.72 vs. 0.96 and 0.81 vs. 0.99; P = .0022 and P = .0068, respectively, for readers 1 and 2). In addition, the sensitivity was 100% (15/15) for both readers and significantly greater than that of conventional MRI (53.3% [8/15] for both readers, P = .0156); however, specificities were not significantly different (82.6% [19/23] vs. 82.6% [19/23] and 91.33% [21/23] vs. 95.7% [22/23]). The interobserver agreement also improved by adding BPAS imaging. CONCLUSIONS: Adding BPAS imaging to conventional MRI and MRA sequences can improve diagnostic capability and sensitivity in suspected VAD cases and be helpful in differentiating it from other causes of vertebral artery narrowing such as atherosclerosis or hypoplasia.


Asunto(s)
Algoritmos , Aterosclerosis/patología , Interpretación de Imagen Asistida por Computador/métodos , Angiografía por Resonancia Magnética/métodos , Disección de la Arteria Vertebral/patología , Adolescente , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
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