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Vasantha Shekar Reddy H, S Nagabushana D, Kattamanchi D, Dakappa A. Nystagmus in a child with nephrotic syndrome. BMJ Case Rep 2024; 17:e259734. [PMID: 38417935 PMCID: PMC10900356 DOI: 10.1136/bcr-2024-259734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2024] Open
Abstract
We report a child with steroid-dependent nephrotic syndrome presenting with excessive irritability, double vision and inability to walk for 5 days. On examination, the child was irritable with Glasgow coma sccale (GCS of 12/15, had bilateral convergent squint (R>L), vertical nystagmus, ataxia without any focal neurological deficits and normal fundus. MRI brain with venogram showed bilateral symmetric FLAIR hyperintensity in the medial thalamus and periaqueductal grey matter showing diffuse restriction with normal venogram. A possibility of Wernicke encephalopathy (WE) was considered and the child was started on thiamine supplementation, following which he had significant improvement in his symptoms. His irritability reduced with significant improvement in the range of eye movements and vertical nystagmus. At 3-month follow-up, the child is asymptomatic with normal gait. Although WE is uncommon in children with nephrotic syndrome, the possibility has to be kept in mind when a child presents with atypical neurological symptoms.
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Affiliation(s)
| | | | | | - Ahish Dakappa
- Pediatrics, MS Ramaiah Medical College Hospital, Bangalore, India
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Rahman MM, Islam F, Afsana Mim S, Khan MS, Islam MR, Haque MA, Mitra S, Emran TB, Rauf A. Multifunctional Therapeutic Approach of Nanomedicines against Inflammation in Cancer and Aging. JOURNAL OF NANOMATERIALS 2022; 2022:1-19. [DOI: 10.1155/2022/4217529] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Cancer is a fatal disorder that affects people across the globe, yet existing therapeutics are ineffective. The development of submicrometer transport for optimizing the biodistribution of systemically provided medications is the focus of nanomedicine. Nanoparticle- (NP-) based treatments may enable the development of novel therapeutic approaches to combat this deadly disorder. In multifunctional, multimodal imaging, and drug delivery carriers, NPs generally play a major role. They have emerged as potential strategies for the invention of innovative therapeutic procedures in the last decade. The exponential growth of nanotechnologies in recent years has increased public awareness of the application of these innovative therapeutic approaches. Many tumor-targeted nanomedicines have been studied in cancer therapy, and there is clear evidence for a significant improvement in the therapeutic index of antineoplastic drugs. Age-related factors such as metabolic and physiological alterations in old age and inadequate animal models are currently understudied in nanomedicine and pharmacology. This review highlighted the most important targeting approaches, as well as public awareness, therapeutic advancements, and future prospects in age-related metabolic variations, and tumor-targeted nanomedicine studies.
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Affiliation(s)
- Md. Mominur Rahman
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Fahadul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Sadia Afsana Mim
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Md. Shajib Khan
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Md. Rezaul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Md. Anamul Haque
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh
| | - Saikat Mitra
- Department of Pharmacy, Faculty of Pharmacy, University of Dhaka, Dhaka 1000, Bangladesh
| | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong 4381, Bangladesh
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Anbar, Swabi, Khyber Pakhtunkhwa, Pakistan
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Whiteley P, Marlow B, Kapoor RR, Blagojevic-Stokic N, Sala R. Autoimmune Encephalitis and Autism Spectrum Disorder. Front Psychiatry 2021; 12:775017. [PMID: 34975576 PMCID: PMC8718789 DOI: 10.3389/fpsyt.2021.775017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 11/29/2021] [Indexed: 11/23/2022] Open
Abstract
The concept of "acquired autism" refers to the hypothesis that amongst the massive heterogeneity that encompasses autism spectrum disorder (ASD) there may be several phenotypes that are neither syndromic nor innate. Strong and consistent evidence has linked exposure to various pharmacological and infective agents with an elevated risk of a diagnosis of ASD including maternal valproate use, rubella and herpes encephalitis. Autoimmune encephalitis (AE) describes a group of conditions characterised by the body's immune system mounting an attack on healthy brain cells causing brain inflammation. The resultant cognitive, psychiatric and neurological symptoms that follow AE have also included ASD or autism-like traits and states. We review the current literature on AE and ASD. Drawing also on associated literature on autoimmune psychosis (AP) and preliminary evidence of a psychosis-linked subtype of ASD, we conclude that AE may either act as a potentially causative agent for ASD, and/or produce symptoms that could easily be mistaken for or misdiagnosed as autism. Further studies are required to discern the connection between AE and autism. Where autism is accompanied by regression and atypical onset patterns, it may be prudent to investigate whether a differential diagnosis of AE would be more appropriate.
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Affiliation(s)
| | - Ben Marlow
- Colchester Hospital, East Suffolk and North Essex NHS Foundation Trust, Colchester, United Kingdom
- The Synapse Centre for Neurodevelopment ESNEFT, Colchester, United Kingdom
| | - Ritika R. Kapoor
- Paediatric Endocrinology, Variety Club Children's Hospital, King's College Hospital NHS Foundation Trust, London, United Kingdom
- Faculty of Medicine and Life Sciences, King's College London, London, United Kingdom
| | | | - Regina Sala
- Centre for Psychiatry, Wolfson Institute, Barts and The London School of Medicine and Dentistry Queen Mary University of London, London, United Kingdom
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Soni S, Ruhela RK, Medhi B. Nanomedicine in Central Nervous System (CNS) Disorders: A Present and Future Prospective. Adv Pharm Bull 2016; 6:319-335. [PMID: 27766216 DOI: 10.15171/apb.2016.044] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 08/25/2016] [Accepted: 09/05/2016] [Indexed: 12/12/2022] Open
Abstract
Purpose: For the past few decades central nervous system disorders were considered as a major strike on human health and social system of developing countries. The natural therapeutic methods for CNS disorders limited for many patients. Moreover, nanotechnology-based drug delivery to the brain may an exciting and promising platform to overcome the problem of BBB crossing. In this review, first we focused on the role of the blood-brain barrier in drug delivery; and second, we summarized synthesis methods of nanomedicine and their role in different CNS disorder. Method: We reviewed the PubMed databases and extracted several kinds of literature on neuro nanomedicines using keywords, CNS disorders, nanomedicine, and nanotechnology. The inclusion criteria included chemical and green synthesis methods for synthesis of nanoparticles encapsulated drugs and, their in-vivo and in-vitro studies. We excluded nanomedicine gene therapy and nanomaterial in brain imaging. Results: In this review, we tried to identify a highly efficient method for nanomedicine synthesis and their efficacy in neuronal disorders. SLN and PNP encapsulated drugs reported highly efficient by easily crossing BBB. Although, these neuro-nanomedicine play significant role in therapeutics but some metallic nanoparticles reported the adverse effect on developing the brain. Conclusion: Although impressive advancement has made via innovative potential drug development, but their efficacy is still moderate due to limited brain permeability. To overcome this constraint,powerful tool in CNS therapeutic intervention provided by nanotechnology-based drug delivery methods. Due to its small and biofunctionalization characteristics, nanomedicine can easily penetrate and facilitate the drug through the barrier. But still, understanding of their toxicity level, optimization and standardization are a long way to go.
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Affiliation(s)
- Shringika Soni
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Rakesh Kumar Ruhela
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
| | - Bikash Medhi
- Department of Pharmacology, Postgraduate Institute of Medical Education & Research, Chandigarh, 160012, India
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Fitting S, Booze RM, Mactutus CF. HIV-1 proteins, Tat and gp120, target the developing dopamine system. Curr HIV Res 2015; 13:21-42. [PMID: 25613135 DOI: 10.2174/1570162x13666150121110731] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 11/17/2014] [Accepted: 12/23/2014] [Indexed: 11/22/2022]
Abstract
In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection.
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Affiliation(s)
| | - Rosemarie M Booze
- Department of Psychology, 1512 Pendleton Street, University of South Carolina, Columbia, SC 29208, USA.
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Abstract
BACKGROUND Wernicke encephalopathy is caused by thiamine (vitamin B1) deficiency. It is generally considered to be a disease of adult alcoholics. However, it is known to occur in the pediatric population and in non-alcoholic conditions. DATA SOURCES We searched PubMed with the key words Wernicke, thiamine, pediatric, children and adolescents and selected publications that were deemed appropriate. RESULTS The global prevalence rates of hunger, poverty and resultant nutrient deprivation have decreased in the 21st century. However, several scenarios which may predispose to Wernicke encephalopathy may be increasingly prevalent in children and adolescents such as malignancies, intensive care unit stays and surgical procedures for the treatment of obesity. Other predisposing conditions include magnesium deficiency and defects in the SLC19A3 gene causing thiamine transporter-2 deficiency. The classic triad consists of encephalopathy, oculomotor dysfunction and gait ataxia but is not seen in a majority of patients. Treatment should be instituted immediately when the diagnosis is suspected clinically without waiting for laboratory confirmation. Common magnetic resonance findings include symmetric T2 hyperintensities in dorsal medial thalamus, mammillary bodies, periaqueductal gray matter, and tectal plate. CONCLUSIONS Wernicke encephalopathy is a medical emergency. Delay in its recognition and treatment may lead to significant morbidity, irreversible neurological damage or even death. This article aims to raise the awareness of this condition among pediatricians.
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Moran LM, Fitting S, Booze RM, Webb KM, Mactutus CF. Neonatal intrahippocampal HIV-1 protein Tat(1-86) injection: neurobehavioral alterations in the absence of increased inflammatory cytokine activation. Int J Dev Neurosci 2014; 38:195-203. [PMID: 25285887 DOI: 10.1016/j.ijdevneu.2014.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 01/05/2023] Open
Abstract
Pediatric AIDS caused by human immunodeficiency virus type 1 (HIV-1) remains one of the leading worldwide causes of childhood morbidity and mortality. HIV-1 proteins, such as Tat and gp120, are believed to play a crucial role in the neurotoxicity of pediatric HIV-1 infection. Detrimental effects on development, behavior, and neuroanatomy follow neonatal exposure to the HIV-1 viral toxins Tat1-72 and gp120. The present study investigated the neurobehavioral effects induced by the HIV-1 neurotoxic protein Tat1-86, which encodes the first and second exons of the Tat protein. In addition, the potential effects of HIV-1 toxic proteins Tat1-86 and gp120 on inflammatory pathways were examined in neonatal brains. Vehicle, 25 μg Tat1-86 or 100 ng gp120 was injected into the hippocampus of male Sprague-Dawley pups on postnatal day 1 (PD1). Tat1-86 induced developmental neurotoxic effects, as witnessed by delays in eye opening, delays in early reflex development and alterations in prepulse inhibition (PPI) and between-session habituation of locomotor activity. Overall, the neurotoxic profile of Tat1-86 appeared more profound in the developing nervous system in vivo relative to that seen with the first exon encoded Tat1-72 (Fitting et al., 2008b), as noted on measures of eye opening, righting reflex, and PPI. Neither the direct PD1 CNS injection of the viral HIV-1 protein variant Tat1-86, nor the HIV-1 envelope protein gp120, at doses sufficient to induce neurotoxicity, necessarily induced significant expression of the inflammatory cytokine IL-1β or inflammatory factors NF-κβ and I-κβ. The findings agree well with clinical observations that indicate delays in developmental milestones of pediatric HIV-1 patients, and suggest that activation of inflammatory pathways is not an obligatory response to viral protein-induced neurotoxicity that is detectable with behavioral assessments. Moreover, the amino acids encoded by the second tat exon may have unique actions on the developing hippocampus.
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Affiliation(s)
- Landhing M Moran
- University of South Carolina, Behavioral Neuroscience Program, Department of Psychology, Columbia, SC 29208, USA
| | - Sylvia Fitting
- University of South Carolina, Behavioral Neuroscience Program, Department of Psychology, Columbia, SC 29208, USA
| | - Rosemarie M Booze
- University of South Carolina, Behavioral Neuroscience Program, Department of Psychology, Columbia, SC 29208, USA
| | - Katy M Webb
- University of South Carolina, Behavioral Neuroscience Program, Department of Psychology, Columbia, SC 29208, USA
| | - Charles F Mactutus
- University of South Carolina, Behavioral Neuroscience Program, Department of Psychology, Columbia, SC 29208, USA.
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Walker SY, Pierre RB, Christie CDC, Chang SM. Neurocognitive function in HIV-positive children in a developing country. Int J Infect Dis 2013; 17:e862-7. [PMID: 23562357 DOI: 10.1016/j.ijid.2013.02.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 02/14/2013] [Accepted: 02/16/2013] [Indexed: 10/27/2022] Open
Abstract
OBJECTIVES We aimed to characterize neurological outcomes and determine the prevalence of HIV encephalopathy in a cohort of HIV-infected children in Jamaica. METHODS Data for 287 HIV-infected children presenting between 2002 and 2008 were reviewed and neurological outcomes characterized. A nested case-control study was conducted between July and September 2009 used 15 randomly selected encephalopathic HIV-infected children aged 7-10 years and 15 matched controls (non-encephalopathic HIV-infected). Their neurocognitive functions were evaluated using clinical assessment and standardized tests for intelligence, short term memory (visuo-spatial and auditory), selective attention, and fine motor and coordination functions. Outcomes were compared using Fisher's exact test and the Mann-Whitney U-test. RESULTS Sixty-seven (23.3%) children were encephalopathic. The median age at diagnosis of HIV encephalopathy was 1.6 years (interquartile range (IQR) 1.1-3.4 years). Predominant abnormalities were delayed milestones (59, 88.1%), hyperreflexia (59, 86.5%), spasticity (50, 74.6%), microcephaly (42, 61.7%), and quadriparesis (21, 31.3%). The median age of tested children was 8.7 years (IQR 7.6-10.8 years) in the encephalopathic group and 9 years (IQR 7.4-10.7 years) in the non-encephalopathic group. Encephalopathic children performed worse in all domains of neurocognitive function (p<0.05). CONCLUSIONS A high prevalence of HIV encephalopathy was noted, and significant neurocognitive dysfunction identified in encephalopathic children. Optimized management through the early identification of neurological impairment and implementation of appropriate interventions is recommended to improve quality of life.
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Affiliation(s)
- S Y Walker
- Department of Child and Adolescent Health, University of the West Indies, Mona, Kingston 7, Jamaica
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Hahn YK, Podhaizer EM, Hauser KF, Knapp PE. HIV-1 alters neural and glial progenitor cell dynamics in the central nervous system: coordinated response to opiates during maturation. Glia 2012; 60:1871-87. [PMID: 22865725 DOI: 10.1002/glia.22403] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 07/12/2012] [Indexed: 02/06/2023]
Abstract
HIV-associated neurocognitive disorders (HANDs) are common sequelae of human immunodeficiency virus (HIV) infection, even when viral titers are well controlled by antiretroviral therapy. Evidence in patients and animal models suggests that neurologic deficits are increased during chronic opiate exposure. We have hypothesized that central nervous system (CNS) progenitor cells in both adult and developing CNS are affected by HIV infection and that opiates exacerbate these effects. To examine this question, neural progenitors were exposed to HIV-1 Tat(1-86) in the developing brain of inducible transgenic mice and in vitro. We examined whether Tat affected the proliferation or balance of progenitor populations expressing nestin, Sox2, and Olig2. Disease relevance was further tested by exposing human-derived progenitors to supernatant from HIV-1 infected monocytes. Studies concentrated on striatum, a region preferentially targeted by HIV and opiates. Results were similar among experimental paradigms. Tat or HIV exposure reduced the proliferation of undifferentiated (Sox2(+)) progenitors and oligodendroglial (Olig2(+)) progenitors. Coexposure to morphine exacerbated the effects of Tat or HIV-1(SF162) supernatant, but partially reversed HIV-1(IIIB) supernatant effects. Populations of Sox2(+) and Olig2(+) cells were also reduced by Tat exposure, although progenitor survival was unaffected. In rare instances, p24 immunolabeling was detected in viable human progenitors by confocal imaging. The vulnerability of progenitors is likely to distort the dynamic balance among neuron/glial populations as the brain matures, perhaps contributing to reports that neurologic disease is especially prevalent in pediatric HIV patients. Pediatric disease is atypical in developed regions but remains a serious concern in resource-limited areas where infection occurs commonly at birth and through breast feeding.
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Affiliation(s)
- Yun Kyung Hahn
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia 23298-0709, USA
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Interactive Effects of Morphine on HIV Infection: Role in HIV-Associated Neurocognitive Disorder. AIDS Res Treat 2012; 2012:953678. [PMID: 22666564 PMCID: PMC3362817 DOI: 10.1155/2012/953678] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 02/13/2012] [Accepted: 03/02/2012] [Indexed: 01/06/2023] Open
Abstract
HIV epidemic continues to be a severe public health problem and concern within USA and across the globe with about 33 million people infected with HIV. The frequency of drug abuse among HIV infected patients is rapidly increasing and is another major issue since injection drug users are at a greater risk of developing HIV associated neurocognitive dysfunctions compared to non-drug users infected with HIV. Brain is a major target for many of the recreational drugs and HIV. Evidences suggest that opiate drug abuse is a risk factor in HIV infection, neural dysfunction and progression to AIDS. The information available on the role of morphine as a cofactor in the neuropathogenesis of HIV is scanty. This review summarizes the results that help in understanding the role of morphine use in HIV infection and neural dysfunction. Studies show that morphine enhances HIV-1 infection by suppressing IL-8, downregulating chemokines with reciprocal upregulation of HIV coreceptors. Morphine also activates MAPK signaling and downregulates cAMP response element-binding protein (CREB). Better understanding on the role of morphine in HIV infection and mechanisms through which morphine mediates its effects may help in devising novel therapeutic strategies against HIV-1 infection in opiate using HIV-infected population.
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Abstract
Central nervous system (CNS) infections are the main cause of seizures and acquired epilepsy in the developing world. Geographical variations determine the common causes in a particular region. Acute seizures are common in severe meningitis, viral encephalitis, malaria, and neurocysticercosis, and in most cases are associated with increased mortality and morbidity, including subsequent epilepsy. Neuronal excitability secondary to proinflammatory signals induced by CNS infections are an important common mechanism for the generation of seizures, in addition to various other specific mechanisms. Newer insights into the neurobiology of these infections and the associated epilepsy could help in developing neuroprotective interventions. Management issues include prompt treatment of acute seizures and the underlying CNS infection, correction of associated predisposing factors, and decisions regarding the appropriate choice and duration of antiepileptic therapy. Strategies for the prevention of epilepsy in CNS infections such as early anti-infective and anti-inflammatory therapy need scientific exploration. Prevention of CNS infections is the only definitive way forward to reduce the burden of epilepsy in developing countries.
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Affiliation(s)
- Pratibha Singhi
- Department of Paediatrics, Advanced Paediatrics Centre, Post Graduate Institute of Medical Sciences and Research, Chandigarh, India.
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Gandhi N, Saiyed ZM, Napuri J, Samikkannu T, Reddy PVB, Agudelo M, Khatavkar P, Saxena SK, Nair MPN. Interactive role of human immunodeficiency virus type 1 (HIV-1) clade-specific Tat protein and cocaine in blood-brain barrier dysfunction: implications for HIV-1-associated neurocognitive disorder. J Neurovirol 2010; 16:294-305. [PMID: 20624003 DOI: 10.3109/13550284.2010.499891] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In recent years, increasing interest has emerged to assess the human immunodeficiency virus type 1 (HIV-1) clade C viral pathogenesis due to its anticipated spread in the United States and other western countries. Previous studies suggest that clade C is less neuropathogenic than clade B; however, the underlying mechanism is poorly understood. Additionally, the interactive role of drugs of abuse such as cocaine on clade C-associated neuropathogenesis has not been reported. In the current study, we hypothesize that HIV-1 clade-specific Tat proteins exert differential effects on blood-brain barrier (BBB) integrity and cocaine further differentially aggravates the BBB dysfunction. We evaluated the effect of Tat B and Tat C and/or cocaine on the BBB integrity using an in vitro model constructed with primary human brain microvascular endothelial cells (HBMECs) and astrocytes. The BBB membrane integrity was measured by transendothelial electrical resistance (TEER) and paracellular permeability was measured by fluorescein isothiocyanate (FITC)-dextran transport assay and monocytes transmigration across the BBB. Results indicate that Tat B disrupts BBB integrity to a greater extent compared to Tat C and cocaine further differentially exacerbates the BBB dysfunction. This BBB dysfunction was associated with altered expression of tight junction proteins zona occuldens (ZO-1) and junctional adhesion molecule (JAM)-2. Thus, these results for the first time delineate the differential role of Tat B and Tat C and/or cocaine in BBB dysfunction, which may be correlated with the clade-specific differences observed in HIV-1-associated neurological disorders.
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Affiliation(s)
- Nimisha Gandhi
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida 33199, USA
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Fitting S, Booze RM, Hasselrot U, Mactutus CF. Dose-dependent long-term effects of Tat in the rat hippocampal formation: a design-based stereological study. Hippocampus 2010; 20:469-80. [PMID: 19489004 DOI: 10.1002/hipo.20648] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The human immunodeficiency virus type 1 (HIV-1) protein transactivator of transcription (Tat) is believed to play a critical role in mediating central nervous system (CNS) pathology in pediatric HIV-1 infection. Long-term neurotoxicity was investigated in a design-based stereology study following intrahippocampal injection of Tat on postnatal day (P)10, a time period that approximates the peak in the rats' rate of brain growth and mimics clinical HIV-1 CNS infection at labor/delivery. The goal was to examine the impact of P10 intrahippocampal Tat injection on the anatomy of the adult hippocampus (5 month) to gain a better understanding about how timing of infection influences the rate of progression of pediatric HIV-1 infection [cf. Fitting et al. (2008a) Hippocampus 18:135-147]. Male P10 Sprague-Dawley rats were bilaterally injected with vehicle or one of three different doses of Tat (5, 25, or 50 mug). Unbiased stereological estimates were used to quantify total neuron number (Nissl stain) in five major subregions of the rat hippocampus: granular layer (GL), hilus of the dentate gyrus (DGH), cornu ammonis fields (CA)2/3, CA1, and subiculum (SUB). Glial cells (astrocytes and oligodendrocytes) were quantified in the DGH and SUB. No significant reduction of neuron number was noted for any of the five hippocampal subregions, in contrast to the very prominent reductions reported when Tat was administered on P1 [Fitting et al. (2008a) Hippocampus 18:135-147]. However, for glial cells, the number of astrocytes in the DGH and SUB as well as the number of oligodendrocytes in the DGH were linear dose dependently increased as a function of dose of Tat. In conjunction with previous stereological research [Fitting et al., (2008a) Hippocampus 18:135-147], the present data suggest that variability in the progression of pediatric HIV/acquired immunodeficiency syndrome (AIDS) may be better understood with the knowledge of the factor of timing of HIV-1 CNS infection.
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Affiliation(s)
- Sylvia Fitting
- Department of Psychology, University of South Carolina, Columbia, South Carolina, USA.
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Neonatal intrahippocampal injection of the HIV-1 proteins gp120 and Tat: differential effects on behavior and the relationship to stereological hippocampal measures. Brain Res 2008; 1232:139-54. [PMID: 18674522 DOI: 10.1016/j.brainres.2008.07.032] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 04/29/2008] [Accepted: 07/09/2008] [Indexed: 11/21/2022]
Abstract
HIV-1 proteins, such as Tat and gp120, are believed to play a crucial role in the central nervous system (CNS) pathology of acquired immune deficiency syndrome (AIDS). The present study sought to determine the potential role of Tat and/or gp120 on behavioral development and the relationship to the long-term effects of the HIV-1 proteins on the rat hippocampus. Male pups of 13 Sprague-Dawley litters were bilaterally injected on postnatal day (P)1. Every litter contributed an animal to each of four treatment condition: VEH (0.5 microl sterile buffer), gp120 (100 ng), Tat (25 microg) or combined gp120+Tat (100 ng+25 microg). Body weight was not affected by either protein treatment. Tat revealed a transient effect on many of the behavioral assessments early in development as well as on preattentive processes and spatial memory in adulthood. Gp120 had more selective effects on negative geotaxis (P8-P10) and on locomotor activity (P94-P96). Combined gp120+Tat effects were noted for eye opening with potential interactive effects of gp120 and Tat on negative geotaxis. Anatomical assessment at approximately 7 1/2 months of age was conducted by using design-based stereology to quantify the total cell number in five hippocampal subregions [granule layer (GL), hilus of the dentate gyrus (DGH), cornu ammonis fields (CA)2/3, CA1, and subiculum (SUB)] [Fitting, S., Booze, R.M., Hasselrot, U., Mactutus, C.F., 2007a. Differential long-term neurotoxicity of HIV-1 proteins in the rat hippocampal formation: a design-based stereological study. Hippocampus 18(2), 135-147]. A relationship between early reflex development and estimated cell number in the adult hippocampus was indicated by simple regression analyses. In addition, estimated number of neurons and astrocytes in the DGH explained 81% of the variance of the distribution of searching behavior in the probe test. Collectively, these data indicate that the DGH may participate in the spatial memory alterations observed in adulthood consequent to neonatal exposure to HIV-1 proteins.
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Fitting S, Booze RM, Hasselrot U, Mactutus CF. Differential long-term neurotoxicity of HIV-1 proteins in the rat hippocampal formation: a design-based stereological study. Hippocampus 2008; 18:135-47. [PMID: 17924522 DOI: 10.1002/hipo.20376] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The human immunodeficiency virus type 1 (HIV-1) proteins, gp120 and Tat, are believed to play a role in mediating central nervous system (CNS) pathology in HIV-1 infected patients. Using design-based stereology, we examined the role of neonatal intrahippocampal injections of gp120 and Tat on the adult hippocampus ( approximately 7(1/2) month). Postnatal day (P)1-treated Sprague-Dawley rats were bilaterally injected with vehicle (VEH, 0.5 microl sterile buffer), gp120 (100 ng), Tat (25 microg) or combined gp120 + Tat (100 ng + 25 microg). Using Nissl-stained tissue sections, we quantified total neurons in five subregions of the rat hippocampus [granual layer (GL), hilus of the dentate gyrus (DGH), cornu ammonis fields (CA)2/3, CA1, and subiculum (SUB)], and total glial cells (astrocytes and oligodendrocytes) in two subregions (DGH and SUB). Estimates of cell area and cell volume were taken in the DGH. There was a significant reduction of neuron number in the CA2/3 subfield by Tat and gp120, and a significant reduction in the DGH by Tat only. For glial cells, numbers of astrocytes in the DGH and SUB were increased by the Tat protein, whereas no effects were noted for gp120. Finally, for oligodendrocytes Tat increased cell number in the DGH but not in any other region; gp120 had no detectable effect in any brain region. Estimates of cell area and cell volume of the three different cell types revealed no significant differences between treatments. Collectively, these results suggest differential effects of gp120 and Tat on the estimated total number of neurons, as well as on the number of glial cells.
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Affiliation(s)
- Sylvia Fitting
- Department of Psychology, University of South Carolina, Columbia, South Carolina SC 29208, USA.
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16
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Gericke GS. Does HIV-1/AIDS-associated frontotemporal neuropathology following perinatal infection influence the development of moral behaviour? Med Hypotheses 2008; 70:1139-46. [PMID: 18255237 DOI: 10.1016/j.mehy.2006.05.074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2006] [Accepted: 05/23/2006] [Indexed: 11/16/2022]
Abstract
While HIV encephalopathy and the AIDS dementia complex are considered hallmark neurologic manifestations of HIV-1 infection, increasing evidence of a continuum of nervous system involvement indicates the existence of an unrecognized number of individuals with milder, mostly cognitive and/or behavioural effects. Questions are raised whether HIV-related frontotemporal neuropathology during critical developmental stages could affect development of the brain networks documented to be involved in moral decisions, and whether this could contribute to the phenomenon of delinquency in an unknown percentage of the current generation of approximately 18-25 year old survivors of early childhood or vertically acquired HIV infection. Carefully planned and executed long term, prospective controlled studies using environmental, clinical, neurological, behavioural, genetic, immune and functional neuroimaging correlates would be required to elucidate whether HIV-specific neuropathology could indeed act as an independent risk factor for the development of a frontotemporal sociopathy syndrome. If such an association is proven, the accelerated development of neurospecific therapies should be a priority, especially for clinically and immunologically stable HIV-infected children. It may be necessary to institute such treatment as early as possible in perinatally infected cases, and maybe even during intrauterine life if HIV-1 is demonstrated to also act as a neurobehavioural teratogen for the developing fetal brain. It may, however, prove to be difficult to separate primary neurobiological from environmental factors, since the epigenetic effects on the host genome of retroviral insertion influencing behavioural gene expression characteristics, and altered gene expression following early life stresses may involve overlapping neurodevelopmental gene regulatory networks. In the meantime it remains necessary to prevent or ameliorate frequent neuropsychiatric morbidity from whatever causes.
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Affiliation(s)
- G S Gericke
- Department of Biomedical Sciences, Tshwane University of Technology, PO Box 2040, Brooklyn Square, 0075 Pretoria, Gauteng, South Africa.
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17
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Schwartz L, Civitello L, Dunn-Pirio A, Ryschkewitsch S, Berry E, Cavert W, Kinzel N, Lawrence DMP, Hazra R, Major EO. Evidence of human immunodeficiency virus type 1 infection of nestin-positive neural progenitors in archival pediatric brain tissue. J Neurovirol 2007; 13:274-83. [PMID: 17613718 DOI: 10.1080/13550280701344975] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) central nervous system (CNS) infection in children is associated with impaired brain growth and neurodevelopmental delays. Neural progenitors are critical for neurogenesis. Human multipotential neural progenitors grown in culture are permissive for HIV-1 infection, but it is not known if infection of these cells occurs in vivo. Brain tissue from pre-highly active antiretroviral therapy (HAART) era pediatric acquired immunodeficiency syndrome (AIDS) patients was examined for evidence of HIV-1 infection of nestin-positive neural progenitors by in situ hybridization; or after laser microdissection harvest, DNA extraction, and polymerase chain reaction (PCR). HIV-1 or viral DNA was identified in nestin-positive cells in four of seven HIV-1-infected children, suggesting in vivo infection of neural progenitors.
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Affiliation(s)
- Lynnae Schwartz
- Laboratory of Molecular Medicine and Neuroscience, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-1296, USA.
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18
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Lindsey JC, Malee KM, Brouwers P, Hughes MD. Neurodevelopmental functioning in HIV-infected infants and young children before and after the introduction of protease inhibitor-based highly active antiretroviral therapy. Pediatrics 2007; 119:e681-93. [PMID: 17296781 DOI: 10.1542/peds.2006-1145] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES The purpose of this work was to examine the effects of HIV infection and the impact of highly active antiretroviral treatment with protease inhibitors on neurodevelopmental functioning during the first 3 years of life. PATIENTS AND METHODS Pediatric AIDS Clinical Trials Group 219/219C is a longitudinal cohort study that has enrolled HIV-infected (HIV+) and HIV-exposed but uninfected (HIV-) infants and children since 1993. Longitudinal profiles of neurodevelopmental functioning as measured by the Bayley Scales of Infant Development were compared by HIV-infection status before and after the availability of highly active antiretroviral therapy with a protease inhibitor and within infants with Bayley tests available before and after initiating protease inhibitor therapy. RESULTS In the pre-protease inhibitor era, mean mental and motor scores in HIV+ (n = 54) infants <1 year of age were significantly lower than those among HIV- infants (n = 221) and remained lower up to 2 years of age. After protease inhibitors became available, mean mental and motor functioning of HIV+ infants (n = 91) <1 year of age were still significantly lower than those of HIV- infants (n = 838). However, against a background of declining scores among the HIV- infants, there was evidence of limited improvement in the HIV+ infants relative to their uninfected peers. Among infants who had Bayley II evaluations before and after starting a protease inhibitor, there was a trend to improved mental and motor scores after initiation of protease inhibitor therapy. CONCLUSIONS The suppression of systemic viral replication and subsequent substantial improvements in survival and immunologic status brought about by highly active antiretroviral therapy have been followed by limited improvements in neurodevelopmental functioning in young children. Additional longitudinal research is needed to better understand the role of antiretroviral therapy as well as the impact of genetic and environmental factors on neurodevelopmental functioning in children affected by HIV.
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Affiliation(s)
- Jane C Lindsey
- Center for Biostatistics in AIDS Research, Harvard School of Public Health, Boston, Massachusetts, USA
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19
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Cantó-Nogués C, Sánchez-Ramón S, Alvarez S, Lacruz C, Muñóz-Fernández MA. HIV-1 infection of neurons might account for progressive HIV-1-associated encephalopathy in children. J Mol Neurosci 2005; 27:79-89. [PMID: 16055948 DOI: 10.1385/jmn:27:1:079] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2004] [Accepted: 02/08/2005] [Indexed: 01/19/2023]
Abstract
Direct and productive infection of neurons in vivo is still a matter of debate, although in vitro experiments have demonstrated that immature neuronal cells can be productively infected by various human immunodeficiency virus (HIV) strains. To address this controversy we have analyzed, using light microscopy and in situ hybridization (ISH), HIV-1 infected cells in brain tissue from four pediatric cases of HIV-1-associated encephalopathy (EP). HIV-1 RNA-expressing cells--therefore, actively infected cells--were detected by ISH in different amounts in all brain specimens from the four children. They mainly correspond to glial cells. However, in two of the four children, who had severe progressive EP, but not in the other two, who had the static form, HIV-1-infected neurons were clearly observed in the cortical brain samples. These results provide initial evidence that HIV-1 can actively infect neurons in vivo in children and show a cortical involvement of HIV brain infection in clear correlation with the clinical EP symptoms.
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Affiliation(s)
- Carmen Cantó-Nogués
- Lab. Inmuno-Biología Molecular y, Hospital General Universitario Gregorio Marañón, Madrid, Spain
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20
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Worlein JM, Leigh J, Larsen K, Kinman L, Schmidt A, Ochs H, Ho RJY. Cognitive and motor deficits associated with HIV-2(287) infection in infant pigtailed macaques: a nonhuman primate model of pediatric neuro-AIDS. J Neurovirol 2005; 11:34-45. [PMID: 15804957 DOI: 10.1080/13550280590901732] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Lentivirus-infected nonhuman primates exhibit behavioral and neurological pathology similar to human immunodeficiency virus (HIV)-infected humans and offer a means to examine the effects of lentivirus infection while controlling for confounding factors inherent in human populations. The purpose of this study was to examine cognitive and motor development in infant macaques vertically infected with HIV-2287. Subjects were 20 infant pigtail macaques (Macaca nemestrina); 8 controls born to uninfected dams, and 12 infants whose dams had been inoculated and infected with HIV-2287 in the third trimester of pregnancy. Eight of these pregnancies had undergone surgical procedures in the form of maternal amniotic catheters or maternal amniotic and fetal carotid artery and jugular vein catheters. Data indicated that catheterization had little or no impact on behavioral development. Seven infants were vertically infected (as measured by polymerase chain reaction (PCR) at birth) and five were not infected (as measured by PCR and coculture on repeated testing). Infected infants attained cognitive and motor milestones at significantly later ages than controls. Uninfected infants, born to infected dams, attained developmental milestones at later ages than controls on all tasks, but this reached statistical significance only for the Fine Motor Task. Attainment of milestones was not correlated with viral dose, maternal CD4+ levels at parturition or infant viral RNA levels at birth. Attainment of milestones was negatively correlated with infants' proportions of CD4+ lymphocytes at birth and significantly correlated with proportions of CD4+ lymphocytes 2 weeks after birth, indicating poorer performance in those infants with a more rapid CD4+ depletion. These cognitive and motor deficits closely resemble those observed in human infants and children infected with HIV and indicate that HIV-2287-infected infant macaques represent an excellent model of pediatric neuro-acquired immunodeficiency syndrome (neuroAIDS).
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Affiliation(s)
- J M Worlein
- Washington National Primate Research Center, University of Washington, Seattle, WA 98195, USA.
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21
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Abstract
Human immunodeficiency virus type I (HIV-1) infection leads to penetration of the central nervous system (CNS) in virtually all infected individuals and HIV-1-induced encephalopathy in a significant number of untreated patients. The molecular mechanisms by which HIV-1 enters the CNS and yields CNS dysfunction are still unclear. Our laboratories and others have begun to explore the direct effects of prioritized HIV-1-specific proteins on diverse human CNS cell types. One of these proteins, the accessory HIV-1 protein Vpr, is a critical moiety in these studies, and will be discussed in this article.
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Affiliation(s)
- Roger J Pomerantz
- Biochemistry and Molecular Pharmacology, Division of Infectious Disease and Environmental Medicine, Center for Human Virology and Biodefense, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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Madhivanan P, Mothi SN, Kumarasamy N, Yepthomi T, Venkatesan C, Lambert JS, Solomon S. Clinical manifestations of HIV infected children. Indian J Pediatr 2003; 70:615-20. [PMID: 14510080 DOI: 10.1007/bf02724249] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Heterosexual contact is the predominant mode of transmission among adults in India with an increasing number of women of childbearing age becoming infected with HIV. Consequently, children in India increasingly getting infected, primarily from vertical transmission. A retrospective review of the profile of HIV infected children attending an HIV clinic in South India is reported. METHODS All HIV-infected children under 15 years of age at the time of first presentation and managed at this center between June 1996 and June 2000 are included in this report. Socio-demographic characteristics and clinical manifestation were collected in a precoded proforme. A complete physical examination and baseline laboratory investigations were performed at entry into the clinic and at subsequent follow-up. RESULTS Fifty-eight HIV-infected children were included: thirty-nine (67.2%) were male with mean age 4 years. Perinatal transmission was the predominant mode of HIV acquisition (67%). Common clinical manifestations in these children at presentation included oral candidiasis (43%), pulmonary tuberculosis (35%), recurrent respiratory infections (26%), bacterial skin infection (21%), papulo-pruritic dermatitis (19%), hepatosplenomegaly and lymphadenopathy (14%) each and chronic diarrhea (7%). CONCLUSION An understanding of the epidemiology of pediatric HIV infection may reveal opportunities to reduce and perhaps eliminate perinatal transmission. Knowledge of clinical manifestations in this setting will help physicians meet the management challenges presented by HIV infected children.
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Affiliation(s)
- Purnima Madhivanan
- YR Gaitonde Centerfor AIDS Research and Education, Chennai, Tamil Nadu, India.
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23
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Sánchez-Ramón S, Bellón JM, Resino S, Cantó-Nogués C, Gurbindo D, Ramos JT, Muñoz-Fernández MA. Low blood CD8+ T-lymphocytes and high circulating monocytes are predictors of HIV-1-associated progressive encephalopathy in children. Pediatrics 2003; 111:E168-75. [PMID: 12563091 DOI: 10.1542/peds.111.2.e168] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE Human immunodeficiency virus type 1 (HIV-1)-associated progressive encephalopathy (PE) is a common and devastating complication of HIV-1 infection in children, whose risk factors have not yet been clearly defined. Regardless of the age of presentation, PE shortens life expectancy. Paradoxically, as survival of patients has been prolonged as a result of the use of antiretroviral therapy, the prevalence of PE has increased. Therefore, a predictive marker of PE emergence is critical. The objective of this study was to determine in an observational study whether any immunologic (CD4(+) and CD8(+) T-lymphocyte counts, monocyte counts) or virologic (viral load [VL], biological characteristics of viral isolates) marker might be predictive of PE and whether any particular marker may be involved in the timing of clinical onset of PE. METHODS A total of 189 children who were vertically infected with HIV-1 were studied retrospectively, 58 of whom fulfilled criteria of the American Academy of Neurology for PE. T-lymphocyte subsets and monocytes in peripheral blood were quantified by flow cytometry. HIV-1 RNA was measured in plasma using a quantitative reverse transcriptase polymerase chain reaction assay. Demographic, clinical, and viro-immunologic characteristics in infants were compared with control groups using logistic regression. Proportions were compared using the chi(2) test or Fisher exact test. For each child, immunologic and virologic markers were analyzed in parallel closely before clinical onset of PE and closely after PE onset and compared by using the Student t test for paired samples. RESULTS Overall, mortality of 58 HIV-1-infected children who developed PE was significantly higher than of children who did not develop this complication. Blood CD8(+) T-lymphocytes <25% in the first months of life suggested a relative risk of progressing to PE 4-fold higher than those with CD8(+) >25% (95% confidence interval: 1.2-13.9) and remained statistically significant after adjustment for treatment. When we compared the PE-positive group with the acquired immunodeficiency syndrome (AIDS)/PE-negative group (children who developed clinical category C and without neurologic manifestations) in a cross-sectional study within 12 months before PE or AIDS diagnosis, respectively, the %CD8(+) T-lymphocytes were significantly lower in the PE-positive group. Normalized absolute counts of CD8(+) T-lymphocytes with respect to seroreverting children were significantly lower in the group of children with encephalopathy with respect to the AIDS/PE-negative group (data not shown). It is interesting that a statistically significant increase was observed in circulating monocyte percentages and absolute counts shortly before the first neurologic symptoms compared with values after PE was established and with those from HIV-1-infected controls. With respect to AIDS-related events, PE was strongly associated with anemia and lymphoid interstitial pneumonitis in the PE-positive group with respect to a group of children with AIDS but without PE. CONCLUSION HIV-1 infection of the central nervous system (CNS) remains an important clinical concern. The first step toward PE prevention in HIV-1-infected children should be directed at predicting risk of PE and thus the prompt and reliable identification of infants who are at risk for CNS disease progression. Low blood CD8(+) T-lymphocytes is a strong early predictive marker of PE emergence in vertical HIV-1 infection. Indeed, among all of the immunologic and virologic variables assessed in this observational study, the only significant difference during the first months of life are the CD8(+) T-lymphocytes. A peak of significantly higher peripheral monocytes before the onset of PE with respect to established PE has not been previously described, and strengthens the growing evidence that an increased traffic of monocytes to the brain may be a key factor in triggering neurologic symptoms. The suppression of HIV-1 replication is dependent on the presence of a relatively small number of HIV-1-specifof HIV-1-specific CD8(+) T-lymphocytes, and it is possible that the duration of the neurologically asymptomatic phase for any given child may depend mostly on the magnitude of specific CD8(+) T-lymphocyte responses. Thus, a decrease of CD8(+) T-lymphocytes would diminish the host capacity to control viral infection, as reported in animal models, enabling infected macrophages to cross the blood-brain barrier. Our results advocate the use of CD8(+) T-lymphocyte and monocyte counts to follow-up HIV-1-infected children. We suggest that CD8(+) T-lymphocytes may be the nexus for many different aspects of the disease, namely loss of control of HIV-1 replication determining higher VL, increased traffic of activated and/or infected monocytes, spread of infection to immune sanctuaries, and finally clinical neurologic emergence of PE. Moreover, we suggest that CD8(+) T-lymphocytes or/and monocytes may be used as putative biological markers of neuropathogenicity. This might suggest their use in decision making of when to start more effective antiretroviral regimens for HIV-1 infection of the CNS and the need of new therapies either to preserve or to augment an adequate CD8(+) T-lymphocyte immune response. Early detection of children who are at risk for developing PE is particularly important because aggressive highly active antiretroviral therapy improves neurologic symptoms, allows possible use of neuroprotective treatment to prevent further development of encephalopathy, and emphasizes the relevance of developing therapies aimed to enhance CD8(+) T-lymphocyte function. In conclusion, the surrogate markers routinely used in clinical practice for HIV-1 infection (ie, CD4(+) T-lymphocyte counts and VL) seem to be insufficient to evaluate the clinical involvement of the CNS. Other systemic markers, as the recent proposed markers for PE evolution (cerebrospinal fluid VL by lumbar puncture and brain atrophy by cerebral magnetic resonance imaging) are undoubtedly more invasive than measuring CD8(+) T-lymphocyte and monocyte counts, when the neurologic manifestations of PE are still preventable.
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Affiliation(s)
- Silvia Sánchez-Ramón
- Unit of Neuroimmunology, Hospital General Universitario Gregorio Marañón, Madrid, Spain
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24
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Mitchell W. Neurological and developmental effects of HIV and AIDS in children and adolescents. MENTAL RETARDATION AND DEVELOPMENTAL DISABILITIES RESEARCH REVIEWS 2002; 7:211-6. [PMID: 11553937 DOI: 10.1002/mrdd.1029] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
HIV-related encephalopathy is an important problem in vertically infected children with HIV. Infected infants may manifest early, catastrophic encephalopathy, with loss of brain growth, motor abnormalities, and cognitive dysfunction. Even without evidence of AIDS, infected infants score lower than serorevertors on developmental measures, particularly language acquisition. Children with perinatal or later transfusion-related infection generally are roughly comparable developmentally to their peers until late in their course. Symptoms similar to adult AIDS dementia complex are occasionally seen in adolescents with advanced AIDS, including dementia, bradykinesia, and spasticity. Opportunistic CNS infections such as toxoplasmosis and progressive multifocal leukoencephalopathy are less common in children and adolescents than in adults. Increasing evidence suggests that aggressive antiretroviral treatment may halt or even reverse encephalopathy. Neuroimaging changes may precede or follow clinical manifestations, and include early lenticulostriate vessel echogenicity on cranial ultrasound, calcifying microangiopathy on CT scan, and/or white matter lesions and central atrophy on MRI. Differential diagnosis of neurological dysfunction in an HIV-infected infant includes the effects of maternal substance abuse, other CNS congenital infections, and other causes of early static encephalopathy. Initial entry of HIV into the nervous system occurs very early in infection. The risk of clinical HIV encephalopathy increases with very early age of infection and with high viral loads. Virus is found in microglia and brain derived macrophages, not neurons. The neuronal effect of HIV is probably indirect, with various cytokines implicated. Apoptosis is the presumed mechanism of damage to neurons by HIV.
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Affiliation(s)
- W Mitchell
- Childrens Hospital Los Angeles, Los Angeles, California 90027, USA.
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25
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Madhivanan P, Mothi SN, Kumarasamy N, Yepthomi T, Lambert J, Solomon S. Regression of attained milestones in an HIV infected infant. Indian J Pediatr 2001; 68:991-3. [PMID: 11758142 DOI: 10.1007/bf02722605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
We report a case of an 18-month-old child with regression of attained developmental milestones as a manifestation of HIV encephalopathy. This is the first such report in Indian literature. Commencing antiretroviral therapy in this child resulted in arrest of further regression of milestones. This alerts pediatricians to be aware that early developmental delay and regression may be a presenting manifestation of HIV infection in a child.
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Affiliation(s)
- P Madhivanan
- YR Gaitonde Centre for AIDS Research and Education, No. 1 Raman Street, T. Nagar, Chennai-17, India
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26
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Mukhtar M, Duke H, BouHamdan M, Pomerantz RJ. Anti-human immunodeficiency virus type 1 gene therapy in human central nervous system-based cells: an initial approach against a potential viral reservoir. Hum Gene Ther 2000; 11:347-59. [PMID: 10680847 DOI: 10.1089/10430340050016076] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Studies have demonstrated that human immunodeficiency virus type 1 (HIV-1) infection of central nervous system (CNS)-based cells in vivo results in a series of devastating clinical conditions collectively termed acquired immune deficiency syndrome (AIDS) dementia complex (ADC). Gene therapy for these neurovirological disorders necessitates utilization of a vector system that can mediate in vivo delivery and long-term expression of an antiretroviral transgene in nondividing/postmitotic CNS cellular elements. The present studies focus on the transfer of an anti-HIV-1 gene to primary isolated CNS microvascular endothelial cells (MVECs) and neuronal-based cells, for its effects in protecting these cells from HIV-1 infection. By using an HIV-1-based vector system, it was possible to efficiently transduce and maintain expression of a marker transgene, beta-galactosidase (beta-Gal), in human CNS MVECs, human fetal astrocytes, plus immature and mature (differentiated) NT2 cells. Significant transduction of the marker gene, beta-Gal, in CNS-based cells prompted the utilization of this system with an anti-HIV-1 gene therapeutic construct, RevM10, a trans-dominant negative mutant Rev protein. Initially, it was not possible to generate any HIV-1 vector particles with the RevM10 gene in the transducing construct, because of inhibitory effects on the HIV-1 vector by this gene product. However, the vector could be partially rescued by adding an additional construct that supplied wild-type rev, in trans, during a multiple construct transfection in the packaging 293T cells. Thus, it was possible to significantly improve the titer of RevM10-expressing viral particles generated from these cells. Moreover, this RevM10 vector transduced the neuronal precursor cell line NT2, retinoic acid-differentiated human neurons (hNT) from the precursor cells, and primary isolated human brain MVECs with high efficiency. RevM10 generated from the HIV-1-based vector system potently inhibited replication of diverse HIV-1 strains in human CNS MVECs and neuronal cells. The data generated from these studies represent an initial approach for future development of anti-HIV-1 gene therapy in the CNS.
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Affiliation(s)
- M Mukhtar
- Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
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27
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Steigerwald ES, Sarter M, March P, Podell M. Effects of feline immunodeficiency virus on cognition and behavioral function in cats. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1999; 20:411-9. [PMID: 10225221 DOI: 10.1097/00042560-199904150-00001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Experimental intravenous challenge of 8-week old cats with the Maryland isolate of feline immunodeficiency virus, Maryland isolate (FIV-MD) was investigated for its effects on cognitive and behavioral function at 12 months postinfection. Six cats infected with FIV-MD were compared with age-matched controls on several behavioral measures. These measures included an open field observation, locomotion tests, traversing planks of various widths for food reinforcement, and a spatial learning task. No group differences were observed on any measure of locomotion. Differences were present with exploratory and stationary activity in the open field observation, with infected cats exhibiting higher levels of exploratory activity and in less stationary activity compared with that of control cats. In the plank-walking experiment, infected cats were less able to successfully cross progressively narrower planks compared with control animals. A holeboard paradigm was constructed to test spatial learning and memory, in which cats were required to locate food reinforcement based on position in the holeboard array. As a group, FIV-infected cats committed more reference (exploring an unbaited cup) and working memory (returning to a previously visited baited cup) errors than control cats. The main difference demonstrated was a higher activity level and associated distractibility in FIV-infected cats that appears to be related to their overall deficient performance when learning new tasks. These results indicate that behavioral function is altered and cognition is quantitatively impaired in FIV-infected cats.
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Affiliation(s)
- E S Steigerwald
- Department of Veterinary Clinical Sciences, Comprehensive Cancer Center, The Ohio State University, Columbus, USA
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28
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Abstract
The authors report two pediatric patients with definite human immunodeficiency virus infection whose initial presentation was stroke and seizure. The first patient was a 3-year-old female who developed acute hemiparesis as the first manifestation. The other, a 2-month-old infant, had focal seizures secondary to cerebral infarction. Investigations revealed ischemic infarction of the thalamus, hypothalamus, and internal capsule in the first patient and cerebral cortex in the second. Further investigations failed to demonstrate any other causes of these cerebral infarctions. Opportunistic infection of the central nervous system was not documented. The authors emphasize that cerebrovascular accident may be the initial presentation in human immunodeficiency virus infection in children. Human immunodeficiency virus infection must be included in the differential diagnosis, and testing for the disease is mandatory in the investigation of stroke in any child who is at risk of having this infection.
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Affiliation(s)
- A Visudtibhan
- Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
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29
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Salvan AM, Lamoureux S, Michel G, Confort-Gouny S, Cozzone PJ, Vion-Dury J. Localized proton magnetic resonance spectroscopy of the brain in children infected with human immunodeficiency virus with and without encephalopathy. Pediatr Res 1998; 44:755-62. [PMID: 9803458 DOI: 10.1203/00006450-199811000-00019] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Twenty children older than 2 y infected with human immunodeficiency virus (HIV) were examined by in vivo proton magnetic resonance spectroscopy (1H MRS) to study their cerebral metabolism and to identify metabolic profiles in relation with different stages of the disease. Patients were rated regarding their clinical and immunologic status according to the Centers for Disease Control classification and were divided into two groups: without encephalopathy (E-, n = 15) and with progressive encephalopathy (E+, n = 5). The acquisition was performed in the centrum semiovale using the short echo stimulated echo acquisition mode 20-ms sequence. The MRS profile was abnormal in all HIV-infected children compared with healthy age-matched controls (n = 7), even when magnetic resonance images were normal. A significant increase of the proportion of the lipid signals (ANOVA, p < 0.05) was found in all HIV-infected children. In addition, a significant decrease of the proportion of the N-acetylaspartate signal and a significant increase of the proportion of the myo-inositol signal (ANOVA, p < 0.05) characterized the E+ group. The principal component analysis performed on eight variables on 30 spectra confirms that the spectra of HIV-infected children differ from control spectra. The E+ group and the E- group are clearly separated on the map of subjects on the principal plane. The E- group lies in an intermediate position between the E+ group and the control group. The evolution of metabolic alterations in the brain of HIV-infected children can clearly be monitored by 1H MRS and associated with the occurrence of an encephalopathy.
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Affiliation(s)
- A M Salvan
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR CNRS 6612, Faculté de Médecine, Marseille, France
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Stefano GB, Salzet M, Bilfinger TV. Long-term exposure of human blood vessels to HIV gp120, morphine, and anandamide increases endothelial adhesion of monocytes: uncoupling of nitric oxide release. J Cardiovasc Pharmacol 1998; 31:862-8. [PMID: 9641470 DOI: 10.1097/00005344-199806000-00009] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Acute exposure of human saphenous vein or internal thoracic artery endothelium to either morphine [27.4 +/- 3.7 and 35.4 +/- 4.1 nM nitric oxide (NO), respectively] or anandamide (18.3 +/- 2.2 and 24.3 +/- 3.0 nM, respectively) results in NO release, whereas exposure to the human immunodeficiency virus envelope protein gp120 does not. After the short-term exposure of the vessel endothelium, monocyte adherence is diminished with morphine and anandamide treatment (jointly by -80%), whereas it is enhanced with that of gp120 (approximately 40%), indicating that gp120 enhances the ability of the endothelium to adhere monocytes. Long-term or continuous exposure of the endothelia to all agents results in a significant enhancement of monocyte adherence (p < 0.05), which is further increased when exposed to either morphine and anandamide plus gp120. This is caused by a desensitization of the endothelium to further NO release after the initial exposure to either anandamide or morphine. The results serve to indicate that in individuals abusing opiates and or cannabinoids, a tissue [i.e., central nervous system (CNS)] viral load may be higher, and acquired immunodeficiency syndrome (AIDS) may progress more rapidly because monocyte adherence and mobility is significantly increased, indicating a higher level of transmembrane migration.
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Affiliation(s)
- G B Stefano
- Multidisciplinary Center for the Study of Aging, Neuroscience Research Institute, State University of New York/College at Old Westbury, 11568, USA
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Stefano GB, Salzet M, Rialas CM, Mattocks D, Fimiani C, Bilfinger TV. Macrophage behavior associated with acute and chronic exposure to HIV GP120, morphine and anandamide: endothelial implications. Int J Cardiol 1998; 64 Suppl 1:S3-13. [PMID: 9687087 DOI: 10.1016/s0167-5273(98)00030-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We demonstrate that immediate exposure to gp120 (5 min; 0.1 microg/ml) results in a significant shift of the macrophage population to an amoeboid and motile category (P<0.01; 91.7+/-5.5 vs. a control value of 42.4+/-4.2) and prior exposure with anti-gp120 antagonizes this shift. Acute exposure of the macrophages to morphine (10(-6) M) or anandamide (10(-6) M) resulted in the cells rounding up (shape factors of 0.84 and 0.87 respectively) and becoming non-motile. The action is blocked by prior treatment with the specific antagonists naloxone and SR 141716A. Chronic exposure (6 h) of the cells to all three agents resulted in a random migration pattern. Further, all agents blocked chemotaxis induced by DAMA and IL-1. Observation of the cells behavior during chronic exposure revealed a sporadic activity pattern with gp120 whereas morphine and anandamide first induced a period of inactivity which is followed by a period of activity (chemokinesis). Recent work from our laboratory has demonstrated that both morphine and anandamide acutely stimulate constitutive macrophage nitric oxide (NO) release, which then induces macrophage rounding and inactivity. It was therefore of interest to examine their behavior by exposing macrophages to the NO-donor SNAP. In a concentration dependent manner SNAP exhibited the same behavioral actions as both substances of abuse. Given this, we next determined if macrophages exposed to gp120 would release NO. We demonstrated that NO was released only when exposed to morphine and anandamide not gp120. Thus. the chemokinetic inducing activities of these agents may be the basis for excitotoxin liberation in neural tissues and/or a higher viral load in various organ systems since cellular adherence and random migration are stimulated.
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Affiliation(s)
- G B Stefano
- Multidisciplinary Center for the Study of Aging, Neuroscience Research Institute, State University of New York/College at Old Westbury, 11568, USA.
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Mitchell TW, Buckmaster PS, Hoover EA, Whalen LR, Dudek FE. Axonal sprouting in hippocampus of cats infected with feline immunodeficiency virus (FIV). JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1998; 17:1-8. [PMID: 9436752 DOI: 10.1097/00042560-199801010-00001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Neurologic dysfunction and neuropathology are common findings in patients infected with HIV and in cats infected with feline immunodeficiency virus (FIV). The pathogenesis of lentivirus-associated alterations in the central nervous system (CNS) is multifactorial. Because seizures, alterations in memory, and behavioral changes are clinical manifestations in adults and children infected with HIV, we explored the possibility that changes in neuronal structure may occur in the hippocampus. To do this, we examined the dentate gyrus of FIV-infected cats, an animal model of HIV infection. Neuropathologic findings included gliosis within the hilus of the dentate gyrus and granule cell axonal sprouting. Using the Timm's method, which labels axons of dentate gyrus granule cells, abnormally high amounts of staining were observed in the inner one third of the molecular layer in 45% of FIV-infected cats (n = 11) and in none of the controls (n = 19). Prominent axonal sprouting was seen in three FIV-infected cats that were infected as kittens, suggesting that younger cats may be more susceptible. Axon reorganization of the dentate granule cells has been hypothesized to underlie complex partial seizure activity in human temporal lobe epilepsy. These results suggest that FIV infection causes granule cell axon reorganization in the hippocampus of cats. A similar neuropathogenetic mechanism may contribute to neurologic dysfunction in HIV-infected patients.
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Affiliation(s)
- T W Mitchell
- Department of Anatomy and Neurobiology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA
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Moreno TN, Fortunato EA, Hsia K, Spector SA, Spector DH. A model system for human cytomegalovirus-mediated modulation of human immunodeficiency virus type 1 long terminal repeat activity in brain cells. J Virol 1997; 71:3693-701. [PMID: 9094643 PMCID: PMC191518 DOI: 10.1128/jvi.71.5.3693-3701.1997] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Previously, our laboratory showed that human cytomegalovirus (HCMV) activates human immunodeficiency virus type 1 (HIV-1) in brain-derived cells with limited HIV-1 gene expression but inhibits HIV-1 in cells fully permissive for replication of both viruses (F. M. Jault, S. A. Spector, and D. H. Spector, J. Virol. 68:959-973, 1994). To investigate these effects further, we developed a model system that uncouples HIV-1 gene expression from long terminal repeat (LTR) activity. Two monoclonal U373-MG astrocytoma/glioblastoma cell lines (LTRIG and LIGHIVDC) were generated, each containing an integrated copy of an LTR-chloramphenicol acetyltransferase (CAT) construct and the Escherichia coli lacI gene. LIGHIVDC also has an inducible HIV-1 genome controlled by a Rous sarcoma virus promoter with lac operator sequences. Basal LTR-mediated CAT activity is 65-fold higher in LIGHIVDC than in LTRIG, and this activity is further increased (20-fold) following incubation of LIGHIVDC with isopropyl-beta-D-thiogalactopyranoside (IPTG). Tat protein can be detected by immunostaining in LIGHIVDC. However, Rev-mediated transport and subsequent translation of the singly spliced and unspliced HIV-1 mRNAs is inefficient. In the absence of Tat, HCMV stimulated CAT activity approximately 20-fold, and this activation required HCMV gene expression but not viral DNA replication. LTR-directed transcription was unaffected by HCMV infection in LIGHIVDC but was inhibited in these cells when they contained increased Tat levels following IPTG induction. These results support the hypothesis that HCMV can induce the HIV-1 LTR when HIV-1 gene expression is minimal and that a threshold level of HIV-1 gene products is necessary for HCMV to inhibit this promoter.
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Affiliation(s)
- T N Moreno
- Department of Biology, University of California, San Diego, La Jolla 92093-0357, USA
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Exhenry C, Nadal D. Vertical human immunodeficiency virus-1 infection: involvement of the central nervous system and treatment. Eur J Pediatr 1996; 155:839-50. [PMID: 8891552 DOI: 10.1007/bf02282832] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
UNLABELLED Involvement of the central nervous system (CNS) contributes substantially to morbidity and mortality of vertical infection with the human immunodeficiency virus (HIV)-1. The clinical spectrum ranges from minor developmental disabilities to severe and progressive encephalopathy. Progression of the disease varies considerably. Both direct viral and indirect host-related pathogenic mechanisms have been proposed. The diagnosis depends on neurological and neurodevelopmental assessments. So far, HIV-1-specific antiviral treatment has shown limited effects on neurological manifestations in symptomatic children. Thus, efforts are needed to improve prevention and treatment of CNS involvement. It is still unclear whether early use of antiretroviral agents is of benefit. CONCLUSION Since experience of treatment of HIV-1 infections in adults cannot easily be translated to children, paediatric clinical trials are needed to answer questions specific to the unique characteristics of children.
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Affiliation(s)
- C Exhenry
- Infectious Diseases Unit, University Children's Hospital of Zurich, Switzerland
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