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1.
Ann Clin Microbiol Antimicrob ; 18(1): 27, 2019 Sep 24.
Article in English | MEDLINE | ID: mdl-31551072

ABSTRACT

BACKGROUND: Identification of all possible HIV reservoirs is an important aspect in HIV eradication efforts. The urinary tract has however not been well studied as a potential HIV reservoir. In this pilot study we molecularly characterized HIV-1 viruses in urine and plasma samples to investigate HIV-1 replication, compartmentalization and persistence in the urinary tract. METHODS: Prospectively collected urine and blood samples collected over 12-36 months from 20 HIV-1 infected individuals were analysed including sampling points from prior to and after ART initiation. HIV-1 pol gene RNA and DNA from urine supernatant and urine pellets respectively were analysed and compared to plasma RNA viruses from the same individual. RESULTS: HIV-1 nucleic acid was detected in urine samples from at least one time point in 8/20 (40%) treatment-naïve subjects compared to 1/13 (7.7%) individuals on antiretroviral treatment (ART) during periods of plasma viral suppression and 1/7 (14.3%) individuals with virological failure. HIV-1 RNA was undetectable in urine samples after ART initiation but HIV-1 DNA was detectable in one patient more than 6 months after treatment initiation. There was co-clustering of urine-derived pol sequences but some urine-derived sequences were interspersed among the plasma-derived sequences. CONCLUSIONS: Suppressive ART reduces HIV-1 replication in the urinary tract but HIV-1 DNA may persist in these cells despite treatment. A larger number of sequences would be required to confirm HIV compartmentalization in the urinary tract.


Subject(s)
Genotype , HIV Infections/virology , HIV-1/classification , HIV-1/isolation & purification , Urinary Tract/virology , Adult , Anti-Retroviral Agents/therapeutic use , DNA, Viral/genetics , DNA, Viral/isolation & purification , Female , HIV Infections/drug therapy , HIV-1/genetics , Humans , Male , Pilot Projects , Plasma/virology , Prospective Studies , RNA, Viral/genetics , RNA, Viral/isolation & purification , Sequence Analysis, DNA , Viral Load , pol Gene Products, Human Immunodeficiency Virus/genetics
2.
Virol J ; 13(1): 170, 2016 10 12.
Article in English | MEDLINE | ID: mdl-27733203

ABSTRACT

BACKGROUND: Although the use of highly active antiretroviral therapy in HIV positive individuals has proved to be effective in suppressing the virus to below detection limits of commonly used assays, virological failure associated with drug resistance is still a major challenge in some settings. The prevalence and effect of pre-treatment resistance associated variants on virological outcomes may also be underestimated because of reliance on conventional population sequencing data which excludes minority species. We investigated long term virological outcomes and the prevalence and pattern of pre-treatment minority drug resistance mutations in individuals initiating HAART at a local HIV clinic. METHODS: Patient's records of viral load results and CD4 cell counts from routine treatment monitoring were used and additional pre-treatment blood samples for Sanger sequencing were obtained. A selection of pre-treatment samples from individuals who experienced virological failure were evaluated for minority resistance associated mutations to 1 % prevalence and compared to individuals who achieved viral suppression. RESULTS: At least one viral load result after 6 months or more of treatment was available for 65 out of 78 individuals followed for up to 33 months. Twenty (30.8 %) of the 65 individuals had detectable viremia and eight (12.3 %) of them had virological failure (viral load > 1000 RNA copies/ml) after at least 6 months of HAART. Viral suppression, achieved by month 8 to month 13, was followed by low level viremia in 10.8 % of patients and virological failure in one patient after month 20. There was potentially reduced activity to Emtricitabine or Tenofovir in three out of the eight cases in which minority drug resistance associated variants were investigated but detectable viremia occurred in one of these cases while the activity of Efavirenz was generally reduced in all the eight cases. CONCLUSIONS: Early viral suppression was followed by low level viremia for some patients which may be an indication of failure to sustain viral suppression over time. The low level viremia may also be representing early stages of resistance development. The mutation patterns detected in the minority variants showed potential reduced drug sensitivity which highlights their potential to dominate after treatment initiation. TRIAL REGISTRATION: Not applicable.


Subject(s)
Anti-HIV Agents/therapeutic use , Drug Resistance, Viral , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/drug effects , HIV-1/genetics , Adult , Aged , CD4 Lymphocyte Count , Female , Follow-Up Studies , Humans , Male , Middle Aged , Mutation , Mutation Rate , Prevalence , Treatment Outcome , Viral Load , Young Adult
3.
Br J Cancer ; 114(10): 1084-9, 2016 05 10.
Article in English | MEDLINE | ID: mdl-27124339

ABSTRACT

BACKGROUND: Recent phase III clinical trials have established the superiority of the anti-PD-1 antibodies pembrolizumab and nivolumab over the anti-CTLA-4 antibody ipilimumab in the first-line treatment of patients with advanced melanoma. Ipilimumab will be considered for second-line treatment after the failure of anti-PD-1 therapy. METHODS: We retrospectively identified a cohort of 40 patients with metastatic melanoma who received single-agent anti-PD-1 therapy with pembrolizumab or nivolumab and were treated on progression with ipilimumab at a dose of 3 mg kg(-1) for a maximum of four doses. RESULTS: Ten percent of patients achieved an objective response to ipilimumab, and an additional 8% experienced prolonged (>6 months) stable disease. Thirty-five percent of patients developed grade 3-5 immune-related toxicity associated with ipilimumab therapy. The most common high-grade immune-related toxicity was diarrhoea. Three patients (7%) developed grade 3-5 pneumonitis leading to death in one patient. CONCLUSIONS: Ipilimumab therapy can induce responses in patients who fail the anti-PD-1 therapy with response rates comparable to previous reports. There appears to be an increased frequency of high-grade immune-related adverse events including pneumonitis that warrants close surveillance.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Melanoma/drug therapy , Skin Neoplasms/drug therapy , Adult , Aged , Antibodies, Monoclonal/adverse effects , Antineoplastic Agents/adverse effects , Drug Administration Schedule , Female , Humans , Ipilimumab , Male , Middle Aged , Neoplasm Metastasis , Retrospective Studies , Treatment Outcome
4.
Antiviral Res ; 127: 90-8, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26704023

ABSTRACT

Approximately 1 million South Africans are infected with Hepatitis C virus (HCV). The standard of care (SOC) in South Africa is combination therapy (pegylated interferon and ribavirin). HCV genotypes and/or mutations in the core/non-structural regions have been associated with response to therapy and/or disease progression. This study examines mutations in the core (29-280 amino acids, including ∼ 90 E1 amino acids) and NS5B (241-306 amino acids) regions on pre-treatment isolates from patients attending Johannesburg hospitals or asymptomatic South African blood donors. Diversity within known CD4+ and CD8+ T-cell epitopes was also explored. Samples grouped into subtypes 1a(N = 10) 1b(N = 12), 3a(N = 5), 4a(N = 3) and 5a(N = 61). Two mutations, associated with interferon resistance-R70Q and T110N-were present in 29 genotype 5a core sequences. No resistance mutation to NS5B nucleotide inhibitors, sofosbuvir was found. Six putative CD8+ and one CD4+ T-cell epitope sequence in the core region showed binding scores of <300 IC50nM to HLA alleles frequently observed in the South African population. No known CD8+ and CD4+ T-cell epitopes were mapped in the NS5B region. The analysis begs the question whether those infected with genotype 5a will benefit better on interferon-free combination therapies. This study provides new insight into one of the lesser studied HCV genotypes and compares the diversity seen in a large pre-treatment cohort with other subtypes.


Subject(s)
Hepacivirus/genetics , Mutation , Viral Core Proteins/genetics , Viral Nonstructural Proteins/genetics , Antiviral Agents/pharmacology , Base Sequence , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/virology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/virology , Drug Resistance, Viral/genetics , Drug Therapy, Combination , Epitopes, T-Lymphocyte/genetics , Female , Gene Frequency , Genotype , HLA Antigens/immunology , Hepacivirus/drug effects , Hepacivirus/immunology , Hepatitis C/blood , Hepatitis C/drug therapy , Hepatitis C/immunology , Hepatitis C/virology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/genetics , Humans , Interferons/therapeutic use , Male , Middle Aged , Molecular Sequence Data , RNA, Viral/genetics , Ribavirin/therapeutic use , Sequence Analysis, Protein , South Africa
5.
Arthritis Rheum ; 64(1): 285-96, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22031171

ABSTRACT

OBJECTIVE: Statins reduce atherosclerosis and cardiovascular morbidity in the general population, but their efficacy and safety in children and adolescents with systemic lupus erythematosus (SLE) are unknown. This study was undertaken to determine the 3-year efficacy and safety of atorvastatin in preventing subclinical atherosclerosis progression in pediatric-onset SLE. METHODS: A total of 221 participants with pediatric SLE (ages 10-21 years) from 21 North American sites were enrolled in the Atherosclerosis Prevention in Pediatric Lupus Erythematosus study, a randomized double-blind, placebo-controlled clinical trial, between August 2003 and November 2006 with 36-month followup. Participants were randomized to receive atorvastatin (n=113) or placebo (n=108) at 10 or 20 mg/day depending on weight, in addition to usual care. The primary end point was progression of mean-mean common carotid intima-media thickening (CIMT) measured by ultrasound. Secondary end points included other segment/wall-specific CIMT measures, lipid profile, high-sensitivity C-reactive protein (hsCRP) level, and SLE disease activity and damage outcomes. RESULTS: Progression of mean-mean common CIMT did not differ significantly between treatment groups (0.0010 mm/year for atorvastatin versus 0.0024 mm/year for placebo; P=0.24). The atorvastatin group achieved lower hsCRP (P=0.04), total cholesterol (P<0.001), and low-density lipoprotein (P<0.001) levels compared with placebo. In the placebo group, CIMT progressed significantly across all CIMT outcomes (0.0023-0.0144 mm/year; P<0.05). Serious adverse events and critical safety measures did not differ between groups. CONCLUSION: Our results indicate that routine statin use over 3 years has no significant effect on subclinical atherosclerosis progression in young SLE patients; however, further analyses may suggest subgroups that would benefit from targeted statin therapy. Atorvastatin was well tolerated without safety concerns.


Subject(s)
Anticholesteremic Agents/therapeutic use , Atherosclerosis/prevention & control , Heptanoic Acids/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Pyrroles/therapeutic use , Adolescent , Atherosclerosis/complications , Atherosclerosis/diagnosis , Atorvastatin , Carotid Intima-Media Thickness , Child , Disease Progression , Double-Blind Method , Female , Humans , Lipids/blood , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/complications , Male , Treatment Outcome , Young Adult
6.
J Virol Methods ; 175(2): 272-7, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21600241

ABSTRACT

The HCV stem-loop subdomains III-a, -b and -c have been shown to reflect the characteristics of the virus and identify isolates by genus, genotype and subtype. The aim of this study was to investigate the genotype-specific PNS within the 5'UTR of prevalent HCV genotypes (1 and 5a) found in South Africa. The genotype 5a (N = 35) and genotype 1 sequences (N=20) were from patients presenting with liver disease or haemophilia, respectively. PNS HCV typing characteristics, defined previously, were observed. The PNS method differentiated subtypes 1a and 1c from subtype 1b by the base change at nucleotide position 243. A lack of structural data from the variable loci V1 of the 5'UTR did not allow us to further differentiate the subtypes of 1. A nucleotide change from a thymine (T) to a cytosine (C) at position 183 was found among genotype 5a sequences. This mutation changed the stable U-AA bond to a Y AA bulge at base-pair position 32. There was an insertion of a single adenine (A) at position 207. At present PNS analysis is labour intensive but, with development of further software to aid the computer analysis, it has the potential to provide a rapid, reliable alternative to phylogenetic analysis.


Subject(s)
Genetic Variation , Hepacivirus/classification , Hepacivirus/genetics , Inverted Repeat Sequences , RNA, Viral/genetics , Base Sequence , Genotype , Hepacivirus/isolation & purification , Humans , Molecular Sequence Data , Sequence Alignment , South Africa
7.
Lupus ; 20(5): 527-30, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21148604

ABSTRACT

We report a case of a 3-month old male infant, born to a mother with a known history of systemic lupus erythematosus (SLE). The infant initially presented with petechiae, anemia, and thrombocytopenia. His evaluation revealed antinuclear antibody (ANA) titer of 1 : 160, negative anti-SS-A/SS-B antibody, positive anti-Smith antibody, elevated anti-dsDNA titer, and a slightly low C4 level. His subsequent development of hematuria with nephrotic grade proteinuria fulfilled criteria for a diagnosis of SLE. His condition improved with corticosteroids, mycophenolate mofetil and low-dose aspirin. At 18 months of age, he is clinically well, off all immunosuppression with normal growth parameters and no detectable autoantibodies.


Subject(s)
Lupus Erythematosus, Systemic/diagnosis , Thrombocytopenia/etiology , Aspirin/administration & dosage , Fibrinolytic Agents/administration & dosage , Glucocorticoids/therapeutic use , Humans , Immunosuppressive Agents/therapeutic use , Infant , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/drug therapy , Male , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/therapeutic use , Prednisolone/therapeutic use , Thrombocytopenia/drug therapy
8.
Lupus ; 19(11): 1315-25, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20861207

ABSTRACT

As part of the Atherosclerosis Prevention in Pediatric Lupus Erythematosus (APPLE) Trial, a prospective multicenter cohort of 221 children and adolescents with systemic lupus erythematosus (SLE) (mean age 15.7 years, 83% female) underwent baseline measurement of markers of cardiovascular risk, including fasting levels of high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), lipoprotein A (Lpa), homocysteine and high-sensitivity C-reactive protein (hs-CRP). A cross-sectional analysis of the baseline laboratory values and clinical characteristics of this cohort was performed. Univariable relationships between the cardiovascular markers of interest and clinical variables were assessed, followed by multivariable linear regression modeling. Mean levels of LDL, HDL, Lpa, TG, hs-CRP and homocysteine were in the normal or borderline ranges. In multivariable analysis, increased Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), prednisone dose, and hypertension (HTN) were independently associated with higher LDL levels. Higher hs-CRP and creatinine clearance were independently related to lower HDL levels. Higher body mass index (BMI), prednisone dose, and homocysteine levels were independently associated with higher TG levels. Only Hispanic or non-White status predicted higher Lpa levels. Proteinuria, higher TG and lower creatinine clearance were independently associated with higher homocysteine levels, while use of multivitamin with folate predicted lower homocysteine levels. Higher BMI, lower HDL, and longer SLE disease duration, but not SLEDAI, were independently associated with higher hs-CRP levels. The R(2) for these models ranged from 7% to 23%. SLE disease activity as measured by the SLEDAI was associated only with higher LDL levels and not with hs-CRP. Markers of renal injury (HTN, proteinuria, and creatinine clearance) were independently associated with levels of LDL, HDL, and homocysteine, highlighting the importance of renal status in the cardiovascular health of children and adolescents with SLE. Future longitudinal analysis of the APPLE cohort is needed to further examine these relationships.


Subject(s)
Biomarkers/blood , Cardiovascular Diseases , Lupus Erythematosus, Systemic , Adolescent , C-Reactive Protein/metabolism , Cardiovascular Diseases/blood , Cardiovascular Diseases/etiology , Child , Cholesterol/blood , Cross-Sectional Studies , Double-Blind Method , Female , Humans , Lipoprotein(a)/blood , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/complications , Placebos , Risk Factors , Triglycerides/blood , Young Adult
9.
Emerg Med J ; 25(5): 276-8, 2008 May.
Article in English | MEDLINE | ID: mdl-18434461

ABSTRACT

BACKGROUND: The risks and benefits of thrombolytic therapy for acute myocardial infarction are usually discussed with patients before treatment. Numerous factors may make it difficult for a patient to understand these issues fully; one of these is the language doctors use to describe risk. STUDY OBJECTIVE: To determine whether emergency department (ED) patients who experience chest pain have the same understanding of the frequency of side effects when expressed as percentages or in descriptive language (eg, "uncommon") as emergency medicine doctors. SETTING: The chest pain area of an urban ED. METHOD: A short questionnaire survey was administered to both patients and ED doctors. RESULTS: Of the 50 patients recruited, 88% correctly understood data when presented as percentages. When patients were asked to identify the frequency of an "uncommon" and "rare" side effect only 22% and 18%, respectively, were able to do so. The corresponding results for the doctors were 70% (p<0.0001) and 54% (p = 0.0006). 39% of patients felt that there was no difference between these two verbal descriptors. CONCLUSION: Patients understand side-effect frequencies when expressed as percentages. Patients have different understandings of the frequency of events to doctors when verbal descriptors are used. This lack of a shared understanding has implications for informed decision-making and we recommend that percentages are used to communicate risk in the ED.


Subject(s)
Emergency Service, Hospital , Myocardial Infarction/drug therapy , Patient Education as Topic/methods , Thrombolytic Therapy/adverse effects , Adolescent , Adult , Aged , Communication , Decision Making , England , Humans , Middle Aged , Patient Participation , Risk Assessment/methods , Surveys and Questionnaires , Terminology as Topic
10.
Rheumatology (Oxford) ; 46(10): 1606-11, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17890275

ABSTRACT

OBJECTIVES: Clinical care and therapeutic trials in idiopathic inflammatory myopathies (IIM) require accurate and consistent assessment of cutaneous involvement. The Cutaneous Assessment Tool (CAT) was designed to measure skin activity and damage in IIM. We describe the development and inter-rater reliability of the CAT, and the frequency of lesions endorsed in a large population of juvenile IIM patients. METHODS: The CAT includes 10 activity, 4 damage and 7 combined lesions. Thirty-two photographic slides depicting IIM skin lesions were assessed by 11 raters. One hundred and twenty-three children were assessed by 11 paediatric rheumatologists at 10 centres. Inter-rater reliability was assessed using simple agreements and intra-class correlation coefficients (ICC). RESULTS: Simple agreements in recognizing lesions as present or absent were generally high (0.5-1.0). ICCs for CAT lesions were moderate (0.4-0.75) in both slides and real patients. ICCs for the CAT activity and damage scores were 0.71 and 0.81, respectively. CAT activity scores ranged from 0 to 44 (median 7, potential range 0-96) and CAT damage scores ranged from 0 to 13 (median 1, potential range 0-22). The most common cutaneous lesions endorsed were periungual capillary loop changes (63%), Gottron's papules/sign (53%), heliotrope rash (49%) and malar/facial erythema (49%). CONCLUSIONS: Total CAT activity and damage scores have moderate to good reliability. Assessors generally agree on the presence of a variety of cutaneous lesions. The CAT is a promising, semi-quantitative tool to comprehensively assess skin disease activity and damage in IIM.


Subject(s)
Dermatomyositis/diagnosis , Severity of Illness Index , Child , Humans , Observer Variation , Reproducibility of Results
12.
Neurocase ; 13(5): 390-401, 2007 Oct.
Article in English | MEDLINE | ID: mdl-18781438

ABSTRACT

Treatment effects of Fast ForWord, hypothesized to ameliorate temporal processing deficits, were demonstrated by magnetoencephalography in a child with dyslexia using four paradigms: Word/Non-word Reading (NW), Grapheme-to-Phoneme Matching (GP), Verbal, and Spatial Working Memory (VWM, SWM). Shifts in brain activation from right inferior frontal and temporal to left frontal, bilateral supramarginal, and transverse temporal regions occurred during GP. During NW, shifts progressed from (1) right or bilateral anterior and superior to (2) left, inferior frontal, to (3) left, superior posterior temporoparietal, to (4) left, inferior, posterior temporooccipital regions. Reading and written language improvements were noted in passage comprehension and spelling.


Subject(s)
Cerebral Cortex/physiopathology , Dyslexia/therapy , Language Therapy/methods , Speech Perception , Therapy, Computer-Assisted/methods , Acoustic Stimulation/methods , Attention , Child , Dyslexia/physiopathology , Female , Humans , Language Therapy/instrumentation , Magnetoencephalography , Treatment Outcome
13.
Bone Marrow Transplant ; 37(7): 629-34, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16501594

ABSTRACT

Autologous hematopoietic cell transplantation (HCT) is being used to treat autoimmune diseases refractory to conventional therapy, including rheumatoid arthritis. Macrophage activation syndrome (MAS) is a descriptive term for a systemic inflammatory disorder that has been described in patients with juvenile rheumatoid arthritis (JRA). This case report describes a young adult with systemic JRA (sJRA) who developed MAS on day # 12 post-autologous transplantation. The patient developed high fever, laboratory evidence of disseminated intravascular coagulation (DIC), hepatocellular injury, pancytopenia and hyper-ferritinemia. All viral, bacterial and fungal studies were negative and the patient improved with high-dose glucocorticosteroid and cyclosporine therapy. Extreme elevation of serum ferritin was documented and helpful in monitoring response to therapy. A number of systemic inflammatory syndromes have been described in association with HCT. These include DIC, 'engraftment syndrome,' infection-associated hemophagocytic syndrome and familial hemophagocytic lymphohistiocytosis. Macrophage activation syndrome presents with features of DIC and is closely related or identical to infection-associated hemophagocytic syndrome. The diagnosis needs to be established in a timely fashion because early and appropriate treatment may improve outcome.


Subject(s)
Autoimmune Diseases/immunology , Hematopoietic Stem Cell Transplantation/adverse effects , Macrophage Activation/immunology , Macrophages/immunology , Adult , Arthritis, Juvenile/diagnosis , Arthritis, Juvenile/immunology , Arthritis, Juvenile/therapy , Autoimmune Diseases/etiology , Autoimmune Diseases/therapy , Humans , Inflammation/immunology , Male , Remission Induction , Syndrome
14.
J Neurooncol ; 77(2): 161-6, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16292486

ABSTRACT

Visual evoked cortical magnetic field (VEF) waveforms were recorded from both hemifields in 21 patients with temporo-parieto-occipital mass lesions to identify preserved visual pathways. Fifteen patients had visual symptoms pre-operatively. Magnetoencephalographic (MEG) VEF responses were detected, using single equivalent current dipole (ECD), in 17/21 patients studied. Displaced or abnormal responses were seen in 15 patients with disruption of pathway in one patient. Three of 21 patients had alterations in the surgical approach or the planned resection based on the MEG findings. The surgical outcome for these three patients suggests that the MEG study may have played a useful role in pre-surgical planning.


Subject(s)
Brain Diseases/physiopathology , Brain Diseases/surgery , Evoked Potentials, Visual/physiology , Magnetoencephalography , Adult , Aged , Aged, 80 and over , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Preoperative Care , Retrospective Studies
15.
Brain Topogr ; 18(1): 1-17, 2005.
Article in English | MEDLINE | ID: mdl-16193262

ABSTRACT

A variety of techniques are available for imaging magnetoencephalographic (MEG) data to the corresponding cortical structures. Each performs a functional optimization that includes mathematical and physical restrictions on source activity. Unlike other imaging techniques, MR-FOCUSS (Multi-Resolution FOCal Underdetermined System Solution) utilizes a wavelet statistical operator that allows spatial resolution to be chosen appropriately for focal or extended sources. Control of focal imaging properties is achieved by specifying P in an l(P) norm distribution template used to construct the wavelets. In addition, incorporation of a multi-resolution wavelet operator desensitizes the mathematical algorithm to noise, (regularization). Like the FOCUSS imaging technique, an initial estimate of cortical activity is recursively enhanced to obtain the final high resolution imaging results. Studies of model MEG data representing all regions of a realistic cortical model are performed to quantify MR-FOCUSS imaging properties. These modeled data studies included single and multiple dipole sources as well as an extended source model. Thus, MR-FOCUSS is found to be very effective for imaging language processing for pre-surgical planning and provides a high-resolution method to image sequential activation of multiple correlated sources involved in language processing.


Subject(s)
Brain Mapping/methods , Cerebral Cortex/physiology , Magnetoencephalography/methods , Signal Processing, Computer-Assisted , Algorithms , Artifacts , Evoked Potentials/physiology , Humans , Language , Language Tests , Models, Neurological , Neurosurgical Procedures/methods , Postoperative Complications/prevention & control , Preoperative Care/methods , Verbal Behavior/physiology
16.
Neurology ; 62(12): 2247-55, 2004 Jun 22.
Article in English | MEDLINE | ID: mdl-15210890

ABSTRACT

OBJECTIVE: To demonstrate noninvasive localization of cognitive cortical areas involved in language processing with magnetoencephalography (MEG) interpreted by multiresolution FOCUSS (MR-FOCUSS), a current density imaging technique. METHOD: MEG data were collected during verb-generation and picture-naming tasks from 18 right-handed control subjects and 24 right-handed patients with epilepsy. RESULTS: The averaged epic data from the verb-generation task, analyzed by MR-FOCUSS, showed initial activation in the left supramarginal gyrus, superior temporal gyrus, and angular gyrus at 239 +/- 31 ms in all subjects, consistent with other language mapping studies. Average amplitude of underlying cortical sources was approximately 452 pAm. The averaged epic data from the picture-naming task, analyzed by MR-FOCUSS, showed activation in the left inferior frontal gyrus (IFG) area starting at 436 +/- 40 ms in all subjects. Average amplitudes of underlying cortical sources were approximately 380 pAm. CONCLUSION: The time course of neuronal language processing can be imaged noninvasively with millisecond resolution by magnetoencephalography using the multiresolution FOCUSS technique.


Subject(s)
Cerebral Cortex/physiology , Epilepsy/physiopathology , Language , Magnetoencephalography , Evoked Potentials , Female , Humans , Male
17.
Ann Neurol ; 50(5): 582-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11706963

ABSTRACT

We investigate and characterize the magnetoencephalographic waveforms from patients during spontaneous and visually induced migraine aura. Direct current neuromagnetic fields were measured during spontaneous onset of migraine auras in 4 migraine patients, and compared with recordings from 8 migraine-with-aura patients and 6 normal controls during visual stimulation of the occipital cortex. Complex direct current magnetoencephalographic shifts, similar in waveform, were observed in spontaneous and visually induced migraine patients, but not in controls. Two-dimensional inverse imaging showed multiple cortical areas activated in spontaneous and visually induced migraine aura patients. In normal subjects, activation was only observed in the primary visual cortex. Results support a spreading, depression-like neuroelectric event occurring during migraine aura that can arise spontaneously or be visually triggered in widespread regions of hyperexcitable occipital cortex.


Subject(s)
Magnetoencephalography , Migraine with Aura/diagnosis , Migraine with Aura/physiopathology , Occipital Lobe/physiopathology , Adult , Brain Mapping , Cortical Spreading Depression , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Photic Stimulation , Visual Cortex/physiopathology
18.
J Rheumatol ; 28(5): 1106-11, 2001 May.
Article in English | MEDLINE | ID: mdl-11361197

ABSTRACT

OBJECTIVE: To examine the validity of the Childhood Health Assessment Questionnaire (CHAQ) in patients with juvenile idiopathic inflammatory myopathy (IIM). METHODS: One hundred fifteen patients were enrolled in a multicenter collaborative study, during which subjects were assessed twice, 7-9 months apart. Physical function was measured using the CHAQ. Internal reliability was assessed using adjusted item-total correlations and item endorsement rates. Construct validity was assessed by comparing predicted and actual correlations of the CHAQ with other measures of physical function and disease activity. Responsiveness was assessed by calculating effect size (ES) and standardized response mean (SRM) in a group of a priori defined "improvers." RESULTS: Item-total correlations were high (rs range = 0.35-0.81), suggesting all items were related to overall physical function. Manual muscle testing and the Childhood Myositis Assessment Scale correlated moderate to strongly with the CHAQ (r = -0.64 and -0.75, both p < 0.001). Moderate correlations were also seen with the physician global assessment of disease activity (rs = 0.58, p < 0.001), parent global assessment of overall health (rs = -0.65, p < 0.001), Steinbrocker function class (rs = 0.69, p < 0.001), and global skin activity (rs = 0.40, p < 0.001), while global disease damage and skin damage had low correlations (rs = 0.13 and 0.07, p > or =0.17). Responsiveness of the CHAQ was high, with ES = 1.05 and SRM = 1.20. CONCLUSION: In this large cohort of patients with juvenile IIM, the CHAQ exhibited internal reliability, construct validity, and strong responsiveness. We conclude that the CHAQ is a valid measure of physical function in juvenile IIM, appropriate for use in therapeutic trials, and potentially in the clinical care of these patients.


Subject(s)
Dermatomyositis/diagnosis , Polymyositis/diagnosis , Surveys and Questionnaires/standards , Adolescent , Child , Child, Preschool , Cohort Studies , Dermatomyositis/therapy , Disability Evaluation , Female , Humans , Male , Polymyositis/therapy , Reproducibility of Results , Treatment Outcome
19.
J Clin Rheumatol ; 7(5): 295-300, 2001 Oct.
Article in English | MEDLINE | ID: mdl-17039159

ABSTRACT

The documentation of treatments used for Juvenile Rheumatoid Arthritis (JRA) is important to allow for the evaluation of practice patterns for future outcome studies. A survey of nine pediatric rheumatologists was performed between September 1999 and February 2000. Each of the physicians prospectively recorded demographic and treatment information on consecutively sampled JRA patients (n=395). Pauciarticular onset JRA was present in 46%, polyarticular onset JRA in 35%, and systemic onset JRA in 19% of the children. Naproxen was the most frequently prescribed medication (55% of the patients), followed by methotrexate (MTX), which was used in 39% of the patients. Folic acid supplementation (1 mg/day) was provided to 69% of the patients treated with MTX. Etanercept was used in 11% of the children. Eleven percent of the patients received corticosteroids, and 13% of children on corticosteroids took calcium supplements. Uveitis was present in 8% and had a chronic course in 79% of those cases. Although systemic medications were used in 50% of the children with uveitis to control eye inflammation, severe damage to the eyes developed in 30% of them. Fourteen percent of the patients required gastroprotective medications. Compared with findings of a similar survey performed in 1993, there was no significant change in the frequency of use of naproxen, but nabumetone is now more often prescribed, and COX-2 inhibitors have been introduced in the therapy of JRA. Changes among second-line agents used for JRA have also occurred, although there was no change in the frequency of use of MTX or corticosteroids. JRA continues to be a treatment challenge for the practicing pediatric rheumatologist. Patients often show incomplete response to the currently available medications. Therefore, new therapeutic agents need to be evaluated for their use in JRA, and the treatment of JRA associated uveitis especially needs to be improved.

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