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1.
J Am Soc Nephrol ; 34(1): 145-159, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36195441

ABSTRACT

BACKGROUND: Ischemia-reperfusion (IR) of a kidney transplant (KTx) upregulates TNF α production that amplifies allograft inflammation and may negatively affect transplant outcomes. METHODS: We tested the effects of blocking TNF peri-KTx via a randomized, double-blind, placebo-controlled, 15-center, phase 2 clinical trial. A total of 225 primary transplant recipients of deceased-donor kidneys (KTx; 38.2% Black/African American, 44% White) were randomized to receive intravenous infliximab (IFX) 3 mg/kg or saline placebo (PLBO) initiated before kidney reperfusion. All patients received rabbit anti-thymocyte globulin induction and maintenance immunosuppression (IS) with tacrolimus, mycophenolate mofetil, and prednisone. The primary end point was the difference between groups in mean 24-month eGFR. RESULTS: There was no difference in the primary end point of 24-month eGFR between IFX (52.45 ml/min per 1.73 m 2 ; 95% CI, 48.38 to 56.52) versus PLBO (57.35 ml/min per 1.73 m 2 ; 95% CI, 53.18 to 61.52; P =0.1). There were no significant differences between groups in rates of delayed graft function, biopsy-proven acute rejection (BPAR), development of de novo donor-specific antibodies, or graft loss/death. Immunosuppression did not differ, and day 7 post-KTx plasma analyses showed approximately ten-fold lower TNF ( P <0.001) in IFX versus PLBO. BK viremia requiring IS change occurred more frequently in IFX (28.9%) versus PLBO (13.4%; P =0.004), with a strong trend toward higher rates of BKV nephropathy in IFX (13.3%) versus PLBO (4.9%; P =0.06). CONCLUSIONS: IFX induction therapy does not benefit recipients of kidney transplants from deceased donors on this IS regimen. Because the intervention unexpectedly increased rates of BK virus infections, our findings underscore the complexities of targeting peritransplant inflammation as a strategy to improve KTx outcomes.Clinical Trial registry name and registration number:clinicaltrials.gov (NCT02495077).


Subject(s)
BK Virus , Kidney Transplantation , Virus Diseases , Humans , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/adverse effects , Kidney Transplantation/methods , Infliximab/therapeutic use , Graft Rejection/prevention & control , Inflammation/drug therapy , Virus Diseases/drug therapy
2.
Am J Transplant ; 22(9): 2169-2179, 2022 09.
Article in English | MEDLINE | ID: mdl-35634722

ABSTRACT

Histopathologic lung allograft injuries are putative harbingers for chronic lung allograft dysfunction (CLAD). However, the mechanisms responsible are not well understood. CXCL9 and CXCL10 are potent chemoattractants of mononuclear cells and potential propagators of allograft injury. We hypothesized that these chemokines would be quantifiable in plasma, and would associate with subsequent CLAD development. In this prospective multicenter study, we evaluated 721 plasma samples for CXCL9/CXCL10 levels from 184 participants at the time of transbronchial biopsies during their first-year post-transplantation. We determined the association between plasma chemokines, histopathologic injury, and CLAD risk using Cox proportional hazards models. We also evaluated CXCL9/CXCL10 levels in bronchoalveolar lavage (BAL) fluid and compared plasma to BAL with respect to CLAD risk. Plasma CXCL9/CXCL10 levels were elevated during the injury patterns associated with CLAD, acute rejection, and acute lung injury, with a dose-response relationship between chemokine levels and CLAD risk. Importantly, there were strong interactions between injury and plasma CXCL9/CXCL10, where histopathologic injury associated with CLAD only in the presence of elevated plasma chemokines. We observed similar associations and interactions with BAL CXCL9/CXCL10 levels. Elevated plasma CXCL9/CXCL10 during allograft injury may contribute to CLAD pathogenesis and has potential as a minimally invasive immune monitoring biomarker.


Subject(s)
Graft vs Host Disease , Lung Transplantation , Allografts , Biomarkers , Chemokine CXCL10 , Chemokine CXCL9 , Graft Rejection/diagnosis , Graft Rejection/etiology , Humans , Lung , Lung Transplantation/adverse effects , Prospective Studies
3.
Pediatr Transplant ; 26(4): e14247, 2022 06.
Article in English | MEDLINE | ID: mdl-35146849

ABSTRACT

BACKGROUND: Long-term survival after lung transplantation (LTx) is limited by chronic lung allograft dysfunction (CLAD). METHODS: We report an analysis of cytokine profiles in bronchoalveolar lavage samples collected during a prospective multicenter non-interventional trial primarily designed to determine the impact of community-acquired respiratory viral infections (CARV) in outcomes after pediatric LTx. In this analysis, we identify potential biomarkers of auto-inflammation and auto-immunity associated with survival and risk of bronchiolitis obliterans (BOS) after LTx with cytokine analysis of bronchoalveolar lavage fluid (BALF) from 61 pediatric recipients. RESULTS: Higher IL-23 (p = .048) and IL-31 (p = .035) levels were associated with the risk of BOS, and lower levels of epithelial growth factor (EGF) (p = .041) and eotaxin (EOX) (p = .017) were associated with BOS. Analysis using conditional inference trees to evaluate cytokines at each visit associated with survival identified soluble CD30 (p < .001), pro-inflammatory cytokine IL-23 (p = .02), and sTNFRI (p = .01) below cutoff levels as associated with BOS-free survival. CONCLUSIONS: Our results indicate that post-LTx survival in children may be linked to activation of alternate pathways of the immune system that affect airway remodeling in addition to activation of "classical" pathways that have been described in adult LTx recipients. These may indicate pathways to target for intervention.


Subject(s)
Bronchiolitis Obliterans , Lung Transplantation , Adult , Bronchiolitis Obliterans/diagnosis , Bronchiolitis Obliterans/etiology , Child , Cytokines/metabolism , Humans , Inflammation , Interleukin-23 , Prospective Studies
4.
Am J Transplant ; 21(9): 3112-3122, 2021 09.
Article in English | MEDLINE | ID: mdl-33752251

ABSTRACT

Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), p = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (p = .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.


Subject(s)
Liver Transplantation , Organ Transplantation , Child , Humans , Immunosuppressive Agents/therapeutic use , Tacrolimus , Transplant Recipients
5.
Am J Transplant ; 19(12): 3284-3298, 2019 12.
Article in English | MEDLINE | ID: mdl-31216376

ABSTRACT

Based on reports in adult lung transplant recipients, we hypothesized that community-acquired respiratory viral infections (CARVs) would be a risk factor for poor outcome after pediatric lung transplant. We followed 61 pediatric lung transplant recipients for 2+ years or until they met a composite primary endpoint including bronchiolitis obliterans syndrome/obliterative bronchiolitis, retransplant, or death. Blood, bronchoalveolar lavage, and nasopharyngeal specimens were obtained with standard of care visits. Nasopharyngeal specimens were obtained from recipients with respiratory viral symptoms. Respiratory specimens were interrogated for respiratory viruses by using multiplex polymerase chain reaction. Donor-specific HLA antibodies, self-antigens, and ELISPOT reactivity were also evaluated. Survival was 84% (1 year) and 68% (3 years). Bronchiolitis obliterans syndrome incidence was 20% (1 year) and 38% (3 years). The primary endpoint was met in 46% of patients. CARV was detected in 156 patient visits (74% enterovirus/rhinovirus). We did not find a relationship between CARV recovery from respiratory specimens and the primary endpoint (hazard ratio 0.64 [95% confidence interval: 0.25-1.59], P = .335) or between CARV and the development of alloimmune or autoimmune humoral or cellular responses. These findings raise the possibility that the immunologic impact of CARV following pediatric lung transplant is different than that observed in adults.


Subject(s)
Bronchiolitis Obliterans/surgery , Community-Acquired Infections/virology , Graft Rejection/virology , Graft Survival/immunology , Lung Transplantation/adverse effects , Respiratory Tract Infections/virology , Virus Diseases/virology , Adolescent , Child , Child, Preschool , Community-Acquired Infections/epidemiology , Community-Acquired Infections/immunology , Female , Follow-Up Studies , Graft Rejection/epidemiology , Graft Rejection/immunology , Humans , Incidence , Infant , Longitudinal Studies , Male , Prognosis , Prospective Studies , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/immunology , Risk Factors , Transplant Recipients , Virus Diseases/epidemiology , Virus Diseases/immunology , Viruses/isolation & purification
6.
Br J Haematol ; 169(2): 262-6, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25612463

ABSTRACT

Serial phlebotomy was performed on sixty children with sickle cell anaemia, stroke and transfusional iron overload randomized to hydroxycarbamide in the Stroke With Transfusions Changing to Hydroxyurea trial. There were 927 phlebotomy procedures with only 33 adverse events, all of which were grade 2. Among 23 children completing 30 months of study treatment, the net iron balance was favourable (-8·7 mg Fe/kg) with significant decrease in ferritin, although liver iron concentration remained unchanged. Therapeutic phlebotomy was safe and well-tolerated, with net iron removal in most children who completed 30 months of protocol-directed treatment.


Subject(s)
Anemia, Sickle Cell/complications , Iron Overload/etiology , Iron Overload/therapy , Phlebotomy , Adolescent , Anemia, Sickle Cell/therapy , Child , Child, Preschool , Female , Ferritins/metabolism , Humans , Iron/metabolism , Liver/metabolism , Liver/pathology , Male , Phlebotomy/adverse effects , Phlebotomy/methods , Transfusion Reaction , Treatment Outcome , Young Adult
7.
Blood ; 124(6): 891-8, 2014 Aug 07.
Article in English | MEDLINE | ID: mdl-24914136

ABSTRACT

The Stroke With Transfusions Changing to Hydroxyurea (SWiTCH) trial compared standard (transfusions/chelation) to alternative (hydroxyurea/phlebotomy) treatment to prevent recurrent stroke and manage iron overload in children chronically transfused over 7 years before enrollment. Standardized brain magnetic resonance imaging/magnetic resonance angiography (MRA) and transcranial Doppler (TCD) exams were performed at entry and exit, with a central blinded review. A novel MRA vasculopathy grading scale demonstrated frequent severe baseline left/right vessel stenosis (53%/41% ≥Grade 4); 31% had no vessel stenosis on either side. Baseline parenchymal injury was prevalent (85%/79% subcortical, 53%/37% cortical, 50%/35% subcortical and cortical). Most children had low or uninterpretable baseline middle cerebral artery TCD velocities, which were associated with worse stenoses (incidence risk ratio [IRR] = 5.1, P ≤ .0001 and IRR = 4.1, P < .0001) than normal velocities; only 2% to 12% had any conditional/abnormal velocity. Patients with adjudicated stroke (7) and transient ischemic attacks (19 in 11 standard/8 alternative arm subjects) had substantial parenchymal injury/vessel stenosis. At exit, 1 child (alternative arm) had a new silent infarct, and another had worse stenosis. SWiTCH neuroimaging data document severe parenchymal and vascular abnormalities in children with SCA and stroke and support concerns about chronic transfusions lacking effectiveness for preventing progressive cerebrovascular injury. The novel SWiTCH vasculopathy grading scale warrants validation testing and consideration for use in future clinical trials. This trial was registered at www.clinicaltrials.gov as #NCT00122980.


Subject(s)
Anemia, Sickle Cell/complications , Anemia, Sickle Cell/diagnosis , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Stroke/diagnosis , Stroke/etiology , Ultrasonography, Doppler, Transcranial , Adolescent , Anemia, Sickle Cell/therapy , Blood Flow Velocity , Blood Transfusion , Brain/blood supply , Brain/pathology , Cerebrovascular Circulation , Child , Child, Preschool , Female , Functional Neuroimaging , Humans , Hydroxyurea/therapeutic use , Male , Prognosis , Secondary Prevention , Stroke/prevention & control , Young Adult
8.
Neurology ; 82(10): 835-41, 2014 Mar 11.
Article in English | MEDLINE | ID: mdl-24523480

ABSTRACT

OBJECTIVE: This study was conducted to determine the relationship of frontal lobe cortical thickness and basal ganglia volumes to measures of cognition in adults with sickle cell anemia (SCA). METHODS: Participants included 120 adults with SCA with no history of neurologic dysfunction and 33 healthy controls (HCs). Participants were enrolled at 12 medical center sites, and raters were blinded to diagnostic group. We hypothesized that individuals with SCA would exhibit reductions in frontal lobe cortex thickness and reduced basal ganglia and thalamus volumes compared with HCs and that these structural brain abnormalities would be associated with measures of cognitive functioning (Wechsler Adult Intelligence Scale, 3rd edition). RESULTS: After adjusting for age, sex, education level, and intracranial volume, participants with SCA exhibited thinner frontal lobe cortex (t = -2.99, p = 0.003) and reduced basal ganglia and thalamus volumes compared with HCs (t = -3.95, p < 0.001). Reduced volume of the basal ganglia and thalamus was significantly associated with lower Performance IQ (model estimate = 3.75, p = 0.004) as well as lower Perceptual Organization (model estimate = 1.44, p = 0.007) and Working Memory scores (model estimate = 1.37, p = 0.015). Frontal lobe cortex thickness was not significantly associated with any cognitive measures. CONCLUSIONS: Our findings suggest that basal ganglia and thalamus abnormalities may represent a particularly salient contributor to cognitive dysfunction in adults with SCA.


Subject(s)
Anemia, Sickle Cell/pathology , Cerebrum/pathology , Cognition Disorders/pathology , Magnetic Resonance Imaging/methods , Adult , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/physiopathology , Basal Ganglia/pathology , Basal Ganglia/physiopathology , Cerebrum/physiopathology , Cognition Disorders/etiology , Cognition Disorders/physiopathology , Female , Humans , Magnetic Resonance Imaging/instrumentation , Male , Middle Aged , Neuropsychological Tests , Prefrontal Cortex/pathology , Prefrontal Cortex/physiopathology , Single-Blind Method , Thalamus/pathology , Thalamus/physiopathology
9.
Pediatr Blood Cancer ; 61(2): 291-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24115743

ABSTRACT

BACKGROUND: The epidemiology of painful episodes in infants and younger children with SCD has not been well studied, particularly for pain managed at home. PROCEDURE: SCD infants identified by newborn screening were enrolled in a longitudinal observational study of pain symptoms requiring parents to report the presence or absence of pain daily. When sickle cell related-pain events occurred, pain occurrence, location, associated symptoms and the treatment provided also were reported. RESULTS: 103 children were enrolled at a median age of 7.2 months; 50 had an SS genotype, 32 SC, 6 SB(0)thalassemia, and 15 SB(+)thalassemia. Parents/guardians reported for a median of 3.8 years (range 0.3-7.6 years) assessing pain for a total of 141,197 days, excluding any period of recurrent transfusions, with an additional 28,079 days of missing data (16%). Children had pain reported on 2,288 days (1.6%), representing 768 distinct episodes of pain, of which 108 required hospitalizations (14%). Pain locations and symptoms consistent with dactylitis were most prevalent (80%) in the 0-12 month age group, and became progressively less prevalent thereafter. Group-based trajectory modeling of pain episode or pain day frequency identified several trajectory groups with progressively older ages of peak pain frequency, which included 40-45% of SS/SB(0)thalassemia and 10-12% of SC/SB(+)thalassemia children. CONCLUSIONS: Pain is relatively infrequent in SCD infants and young children and commonly managed at home. Analyses of longitudinal pain trajectories suggest several different pain trajectories, differing in their frequency, age of onset, and age at peak pain frequency with clinical implications for hydroxyurea management.


Subject(s)
Anemia, Sickle Cell/complications , Pain/etiology , Age Factors , Anemia, Sickle Cell/therapy , Child, Preschool , Female , Follow-Up Studies , Health Services , Hospitalization , Humans , Hydroxyurea/therapeutic use , Infant , Longitudinal Studies , Male , Pain/diagnosis , Pain/drug therapy , Prognosis
10.
Int Arch Allergy Immunol ; 157(3): 269-74, 2012.
Article in English | MEDLINE | ID: mdl-22042247

ABSTRACT

BACKGROUND: This study was carried out to determine whether humoral and cellular immune responses would be provoked by cutaneous administration of keyhole limpet hemocyanin (KLH) and in particular by scarification of the skin (SS). METHODS: This was an unblinded, single-center, 8-week pilot study in healthy young adults. Twenty-four subjects assigned to 4 groups completed the study. Each group was immunized twice, with a 3-week interval, either by SS or intradermally (ID), with an SS dose of 50 or 250 µg and an ID dose of 100 or 250 µg. Serum was collected for antibody assays at baseline and 3 weeks after both the first and second immunizations. Delayed-type hypersensitivity (DTH) testing was performed before the first immunization and 3 weeks after the second. RESULTS: In the 250-µg SS group, there was a significant increase from day 0 to day 47 in anti-KLH IgG (p = 0.02; day 0: 3.46 ± 5.49 mg/dl, day 47: 7.54 ± 8.87 mg/dl) and anti-KLH IgA (p = 0.04; day 0: 4.78 ± 9.15 mg/dl, day 47: 11.42 ± 13.62 mg/dl). One subject in each treatment group showed a positive DTH test result representing 20% (50-µg SS), 10% (250-µg SS), 25% (100-µg ID) and 20% (250-µg ID) of the subjects. CONCLUSIONS: It was possible to induce both humoral and cellular immune responses by SS administration despite the limited antigenic potency of the low-molecular-weight KLH preparation. This approach may be useful for studying the mechanisms of immune response in allergic skin diseases such as atopic dermatitis.


Subject(s)
Hemocyanins/immunology , Hypersensitivity, Delayed/immunology , Immunity, Cellular , Immunity, Humoral , Immunotherapy, Active/methods , Adjuvants, Immunologic/administration & dosage , Administration, Cutaneous , Adolescent , Adult , Female , Hemocyanins/administration & dosage , Humans , Hypersensitivity, Delayed/diagnosis , Immunoglobulin A/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Injections, Intradermal , Male , Pilot Projects , Young Adult
11.
Br J Haematol ; 155(2): 263-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21848879

ABSTRACT

Tapered oral dexamethasone for acute chest syndrome (ACS) in sickle cell anaemia was studied using a novel ACS assessment tool and investigational biomarkers. Twelve participants were randomized (mean age 17·3 years) before early study termination. Dexamethasone decreased duration of hospitalization for ACS by 20·8 h compared to placebo (P = 0·024). Rebound pain occurred in both groups (3 dexamethasone versus 1 placebo). Overall, dexamethasone decreased the leucocyte activation biomarker, sL-selectin; however, participants with rebound pain had higher sL-selectin within 24 h of treatment (dexamethasone or placebo). This ACS assessment tool was feasibly applied, and sL-selectin is a promising biomarker of ACS therapy.


Subject(s)
Acute Chest Syndrome/drug therapy , Anemia, Sickle Cell/complications , Dexamethasone/therapeutic use , Acute Chest Syndrome/blood , Acute Chest Syndrome/etiology , Acute Chest Syndrome/therapy , Adolescent , Adult , C-Reactive Protein/analysis , Cell Adhesion Molecules/blood , Child , Child, Preschool , Combined Modality Therapy , Dexamethasone/administration & dosage , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Humans , Male , Middle Aged , Nitric Oxide/blood , Oxygen Inhalation Therapy , Sickle Cell Trait/complications , Treatment Outcome , Young Adult , beta-Thalassemia/complications
12.
Br J Haematol ; 152(6): 771-6, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21275961

ABSTRACT

In a phase-II multi-centre double-blinded trial, we evaluated haematological effects of oral hydroxycarbamide (HC) and magnesium (Mg) in patients with HbSC, aged 5-53 years old. Subjects were randomized to HC + placebo, Mg + placebo, HC + Mg, or placebo + placebo. The primary endpoint was the proportion of hyperdense red blood cells after 8 weeks. Thirty-six subjects were evaluable, but the study was terminated early because of slow enrollment. In the combined HC groups, mean cell volume and HbF were increased, but differences were not seen in hyperdense red cells or vaso-occlusive events. Mg had no effects. Further investigation of hydroxycarbamide as monotherapy in HbSC disease is warranted.


Subject(s)
Antisickling Agents/therapeutic use , Hemoglobin SC Disease/drug therapy , Hydroxyurea/therapeutic use , Magnesium/therapeutic use , Adolescent , Adult , Biomarkers/blood , Cell Adhesion/drug effects , Child , Child, Preschool , Double-Blind Method , Erythrocyte Indices/drug effects , Erythrocytes/drug effects , Erythrocytes/physiology , Female , Fetal Hemoglobin/metabolism , Hemoglobin SC Disease/blood , Humans , Hydroxyurea/adverse effects , Magnesium/adverse effects , Male , Middle Aged
13.
Am J Hematol ; 86(2): 203-5, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21264908

ABSTRACT

Adults with Sickle Cell Disease (SCD) experience multiple disease-related complications, but few studies have examined relationships between these events and health-related quality of life (HRQOL). We determined the number and type of previous or co-occurring SCD-related complications and their reported HRQOL in a cohort of 1,046 adults from the Comprehensive Sickle Cell Centers (CSCC). Participants had a median age of 28.0 years (48% male, 73% SS or Sß° thalassemia) and had experienced several SCD-related complications (mean 3.8 ± 2.0), which were influenced by age, gender, and hemoglobinopathy type (P < 0.0001). In multivariate models, increasing age reduced all SF-36 scales scores (P < 0.05) except mental health, while female gender additionally diminished physical function and vitality scale scores (P < 0.01). Of possible complications, only vaso-occlusive crisis, asthma, or avascular necrosis diminished SF-36 scale scores. Chronic antidepressants usage predominantly diminished scores on bodily pain, vitality, social functioning, emotional role, and mental health scales, whereas chronic opioid usage diminished all scale scores (P < 0.01). Our study documents substantial impairment of HRQOL in adults with SCD that was influenced by only a few of many possible medical complications. It suggests that more effective treatments of persistent pain and depression would provide the largest HRQOL benefit.


Subject(s)
Aging , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/psychology , Depression/complications , Pain/complications , Quality of Life/psychology , Adolescent , Adult , Aged , Ambulatory Care Facilities , Analgesics, Opioid/therapeutic use , Anemia, Sickle Cell/physiopathology , Anemia, Sickle Cell/therapy , Antidepressive Agents/therapeutic use , Asthma/complications , Cohort Studies , Comprehensive Health Care , Depression/drug therapy , Female , Hip Joint/pathology , Humans , Leg Ulcer/complications , Male , Middle Aged , Osteonecrosis/etiology , Pain/drug therapy , Pain/etiology , Sex Characteristics , Shoulder Joint/pathology , Vascular Diseases/complications , Young Adult
14.
JAMA ; 303(18): 1823-31, 2010 May 12.
Article in English | MEDLINE | ID: mdl-20460621

ABSTRACT

CONTEXT: Sickle cell anemia (SCA) is a chronic illness causing progressive deterioration in quality of life. Brain dysfunction may be the most important and least studied problem affecting individuals with this disease. OBJECTIVE: To measure neurocognitive dysfunction in neurologically asymptomatic adults with SCA vs healthy control individuals. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study comparing neuropsychological function and neuroimaging findings in neurologically asymptomatic adults with SCA and controls from 12 SCA centers, conducted between December 2004 and May 2008. Participants were patients with SCA (hemoglobin [Hb] SS and hemoglobin level < or = 10 mg/dL) aged 19 to 55 years and of African descent (n = 149) or community controls (Hb AA and normal hemoglobin level) (n = 47). Participants were stratified on age, sex, and education. MAIN OUTCOME MEASURES: The primary outcome measure was nonverbal function assessed by the Wechsler Adult Intelligence Scale, third edition (WAIS-III) Performance IQ Index. Secondary exploratory outcomes included performance on neurocognitive tests of executive function, memory, attention, and language and magnetic resonance imaging measurement of total intracranial and hippocampal volume, cortical gray and white matter, and lacunae. RESULTS: The mean WAIS-III Performance IQ score of patients with SCA was significantly lower than that of controls (adjusted mean, 86.69 for patients with SCA vs 95.19 for controls [mean difference, -5.50; 95% confidence interval {CI}, -9.55 to -1.44]; P = .008), with 33% performing more than 1 SD (<85) below the population mean. Among secondary measures, differences were observed in adjusted mean values for global cognitive function (full-scale IQ) (90.47 for patients with SCA vs 95.66 for controls [mean difference, -5.19; 95% CI, -9.24 to -1.13]; P = .01), working memory (90.75 vs 95.25 [mean difference, -4.50; 95% CI, -8.55 to -0.45]; P = .03), processing speed (86.50 vs 97.95 [mean difference, -11.46; 95% CI, -15.51 to -7.40]; P < .001), and measures of executive function. Anemia was associated with poorer neurocognitive function in older patients. No differences in total gray matter or hippocampal volume were observed. Lacunae were more frequent in patients with SCA but not independently related to neurocognitive function. CONCLUSION: Compared with healthy controls, adults with SCA had poorer cognitive performance, which was associated with anemia and age.


Subject(s)
Anemia, Sickle Cell/complications , Anemia, Sickle Cell/physiopathology , Anemia/complications , Brain/pathology , Cognition Disorders/complications , Adult , Age Factors , Anemia/etiology , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Hypoxia, Brain/complications , Hypoxia, Brain/etiology , Intelligence Tests , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests
15.
Am J Bot ; 96(5): 897-903, 2009 May.
Article in English | MEDLINE | ID: mdl-21628242

ABSTRACT

Mutualisms are key interactions that affect population dynamics and structure communities, but the extent to which mutualists can attract potential partners may depend on community context. Many studies have shown that leaf herbivory reduces pollinator visitation and have focused on reduced floral visual display and rewards as potential mechanisms. However, olfactory display plays a critical role in mediating interactions between plants, herbivores, and pollinators. We simulated leaf damage in Cucurbita pepo subsp. texana and measured fragrance emission and other floral characters of both male and female flowers. Contrary to our expectations, damage increased fragrance production, but only in male flowers. Female flowers, which were bigger and produced more fragrance than males, were unaffected by leaf damage. The greatest increase in floral fragrance compounds was in the terpenoids, which we hypothesize could be byproducts of defensively induced cucurbitacins, or they may function defensively themselves. In summary, this study is the first to demonstrate changes in floral fragrance due to leaf damage. Such changes in floral fragrance following herbivory may be a critical and overlooked mechanism mediating interactions between plants, herbivores, and pollinators.

16.
J Pediatr ; 151(3): 260-5, 265.e1, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17719934

ABSTRACT

OBJECTIVE: To determine if INH-A21, an intravenous immune globulin (IGIV) derived from donors with high titers of antibody to surface adhesins of Staphylococcus epidermidis and S. aureus prevents late-onset sepsis (LOS) in very low birth weight (VLBW) infants. STUDY DESIGN: In this double-blind, placebo-controlled study, infants with birth weights 500 to 1250 g were randomized to receive up to four doses of INH-A21 (Veronate) or placebo. The primary objective was to determine the safety and efficacy of INH-A21 versus placebo for prevention of S. aureus LOS in VLBW infants. RESULTS: A total of 1983 infants from 95 neonatal intensive care units were randomized, and received at least one dose of study drug. S. aureus LOS developed in 50 of 989 (5%) and 60 of 994 (6%) infants who received placebo or INH-A21, respectively (P = .34). No differences were found in the frequencies of LOS caused by coagulase-negative staphylococci (CoNS), Candida spp, or overall mortality. No adverse events were statistically significantly associated with INH-A21 infusions compared with placebo. CONCLUSION: INH-A21 failed to reduce the incidence of staphylococcal LOS or candidemia in premature infants.


Subject(s)
Cross Infection/prevention & control , Immunoglobulins, Intravenous/therapeutic use , Immunologic Factors/therapeutic use , Infant, Premature, Diseases/prevention & control , Sepsis/microbiology , Sepsis/prevention & control , Staphylococcal Infections/prevention & control , Age of Onset , Comorbidity , Double-Blind Method , Female , Humans , Infant, Newborn , Infant, Premature , Infant, Very Low Birth Weight , Length of Stay , Male , Sepsis/epidemiology , Time Factors
17.
Clin Infect Dis ; 45(5): 643-9, 2007 Sep 01.
Article in English | MEDLINE | ID: mdl-17683002

ABSTRACT

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) coreceptor tropism, the ability of the virus to enter cells via CCR5 or CXCR4, is a viral characteristic mediated by the envelope gene. The impact of coreceptor tropism on the natural history of HIV-1 infection has not been fully explored. METHODS: Coreceptor tropism was measured using a recombinant virus single-cycle assay on plasma specimens obtained at baseline from 126 children and adolescents in the Hemophilia Growth and Development Study cohort who were enrolled from 1989 through 1990 and underwent follow-up through 1997. RESULTS: Detectable CXCR4-using virus at baseline was associated with a lower baseline CD4(+) T cell count and a higher plasma HIV-1 RNA level. In addition, it independently predicted a greater decrease in CD4(+) T cell count over time (P<.001) and was associated with a 3.8-fold increased risk of progression to clinical AIDS. CONCLUSIONS: This study demonstrates that coreceptor tropism, as assessed by this single-cycle assay, independently influences the natural history of HIV-1 disease.


Subject(s)
HIV Infections/physiopathology , HIV-1/pathogenicity , Receptors, CCR5/immunology , Receptors, CXCR4/immunology , Adolescent , Adult , CD4 Lymphocyte Count , Child , Disease Progression , Hemophilia A/virology , Humans , Kaplan-Meier Estimate , Longitudinal Studies , Male , RNA, Viral/blood , United States , Viral Load
18.
Pediatr Infect Dis J ; 24(10): 858-66, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16220082

ABSTRACT

BACKGROUND: Prophylactic administration of intravenous immunoglobulin has been inconsistent in reducing the risk of sepsis in very low birth weight (VLBW) infants presumably because of varying titers of organism specific IgG antibodies. INH-A21 is an intravenous immunoglobulin from donors with high titers of antistaphylococcal antibodies. This dose-ranging study explored safety and preliminary activity of INH-A21 for prevention of staphylococcal sepsis in VLBW infants. METHODS: This was a multicenter, double blind, group-sequential study. Infants with birth weights 500-1250 g were randomized to receive up to 4 doses of placebo, 250 mg/kg, 500 mg/kg or 750 mg/kg INH-A21. Safety and frequencies of sepsis were compared across treatment groups. RESULTS: All treatment groups had similar mean gestational age, birth weight, Apgar score and maternal use of antibiotics. Randomizations to 250 mg/kg (N = 94) and 500 mg/kg (N = 96) doses were terminated after interim analyses demonstrated a low probability of finding a difference when compared with placebo. Infants randomized to the INH-A21 750 mg/kg group (N = 157) had fewer episodes of Staphylococcus aureus sepsis [relative risk (RR), 0.37; 95% confidence interval (CI), 0.12-1.12; P = 0.14], candidemia (RR 0.34; 95% CI 0.09-1.22; P = 0.09) and mortality (RR 0.64; 95% CI 0.25-1.61; P = 0.27) when compared with the placebo-treated cohort (N = 158). No dose-related trends were observed for adverse events or morbidities associated with prematurity. CONCLUSIONS: INH-A21 750 mg/kg demonstrated potential to reduce sepsis caused by S. aureus, candidemia and mortality in VLBW infants. Although statistical significance was not reached, based on the magnitude of the estimated differences, the efficacy and safety of INH-A21 750 mg/kg should be evaluated in an adequately powered, well-controlled study.


Subject(s)
Cross Infection/prevention & control , Immunoglobulins, Intravenous/adverse effects , Immunoglobulins, Intravenous/therapeutic use , Infant, Premature, Diseases/prevention & control , Infant, Very Low Birth Weight , Sepsis/prevention & control , Cross Infection/mortality , Double-Blind Method , Female , Humans , Immunoglobulins, Intravenous/administration & dosage , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/etiology , Infant, Premature, Diseases/mortality , Male , Sepsis/etiology , Sepsis/mortality , Staphylococcus/immunology , Treatment Outcome
19.
AIDS ; 19(9): 871-7, 2005 Jun 10.
Article in English | MEDLINE | ID: mdl-15905667

ABSTRACT

OBJECTIVE: To determine the influence of pol replication capacity on the natural history of HIV-1 infection. DESIGN: Pol replication capacity was measured using a recombinant virus single cycle assay on baseline plasma specimens from subjects enrolled in the Hemophilia Growth and Development Study. SETTING: Children and adolescents with hemophilia and HIV-1 infection were enrolled at multiple sites across the USA into a natural history study. PARTICIPANTS: The Hemophilia Growth and Development Study enrolled 207 HIV-1-infected hemophiliacs between 6 and 19 years of age in 1989 and 1990. Subjects were followed every 6 months through 1997 with pol replication capacity measurements available from 128 of the subjects. MAIN OUTCOME MEASURES: A univariate model defined the relationship between pol replication capacity and HIV-1 RNA and CD4 T-cell number. A random effects model assessed the ability of this measure to predict CD4 T-cell decline over time and a Cox proportional hazards model and Kaplan-Meier analyses defined how it predicts clinical progression. RESULTS: Pol replication capacity measures correlated with baseline HIV-1 RNA, R = 0.189 (P = 0.03) and CD4 T-cell number, -0.197 (P = 0.03). It also independently predicted CD4 T-cell decline over time and progression to AIDS. CONCLUSIONS: This study demonstrates that pol replication capacity independently influences the natural history of HIV-1 infection.


Subject(s)
Genes, pol , HIV Infections/virology , HIV-1/genetics , Adolescent , Adult , CD4 Lymphocyte Count , Child , Disease Progression , Epidemiologic Methods , HIV Infections/immunology , HIV-1/isolation & purification , HIV-1/physiology , Hemophilia A/complications , Humans , Male , RNA, Viral/genetics , Viral Load , Virus Replication
20.
Am Heart J ; 146(4): 662-7, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14564320

ABSTRACT

BACKGROUND: Arterial compliance is related to left ventricular hypertrophy and risk for cardiovascular disease events; however, its association with coronary artery stenosis remains uncertain. We sought to assess the relation between lower extremity arterial compliance and presence of angiographically defined coronary artery disease. METHODS: Lower extremity arterial compliance was measured with the use of a noninvasive air plethysmography technique in 376 subjects undergoing routine diagnostic coronary angiography. RESULTS: Measures of calf arterial compliance were significantly associated with the presence of one or more stenoses > or =50% compared with no stenoses, even after adjustment for age, sex, smoking, diabetes, hypertension, hypercholesterolemia, and obesity (P =.03). Measures of thigh arterial compliance were also lower in subjects with disease, although this association did not reach statistical significance (P =.07). Receiver operator curves illustrate the incremental predictive ability of calf arterial compliance over and above age, sex, and conventional risk factors. CONCLUSIONS: Lower extremity arterial compliance is associated with presence of significant coronary stenoses in a cardiac catheterization laboratory referral population. This observation lends support for additional efforts to determine the utility of vascular stiffness measures in both clinical and pre-clinical populations to guide treatment and prevention efforts.


Subject(s)
Coronary Stenosis/diagnostic imaging , Leg/blood supply , Adult , Aged , Arteries/physiopathology , Compliance , Coronary Angiography , Female , Humans , Hypertrophy, Left Ventricular/etiology , Male , Middle Aged , Plethysmography/methods , ROC Curve , Reproducibility of Results , Risk Factors , Statistics as Topic
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