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Experience on postmortem minimally invasive tissue sampling to ascertain the cause of death determination in South African children: A case for implementing as standard of care. S Afr Med J 2024; 114:e1538. [PMID: 38525575 DOI: 10.7196/samj.2024.v114i2.1538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/06/2023] [Indexed: 03/26/2024] Open
Abstract
Determining the death burden for prioritising public health interventions necessitates detailed data on the causal pathways to death. Postmortem minimally invasive tissue sampling (MITS), incorporating histology, molecular and microbial culture diagnostics, enhances cause-of-death attribution, particularly for infectious deaths. MITS proves a valid alternative to full diagnostic autopsies, especially in low- and middle-income countries. In Soweto, South Africa (SA), the Child Health and Mortality Prevention Surveillance (CHAMPS) programme has delineated over 1 000 child and stillbirth deaths since 2017. This SA CHAMPS site supports advocating for the use of postmortem MITS as routine practice, for more granular insights into under-5 mortality causes. This knowledge is crucial for SA's pursuit of Sustainable Development Goal 3.2, targeting reduced neonatal and under-5 mortality rates. This commentary explores the public health advantages and ethicolegal considerations surrounding implementing MITS as standard of care for stillbirths, neonatal and paediatric deaths in SA. Furthermore, based on the data from CHAMPS, we present three pragmatic algorithmic approaches to the wide array of testing options for cost-effectiveness and scalability of postmortem MITS in South African state facilities.
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Bronchiolitis versus bronchopneumonia: navigating antibiotic use within the LRTI spectrum. S Afr Med J 2023; 113:20-23. [PMID: 37278266 DOI: 10.7196/samj.2023.v113i6.709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Accepted: 02/06/2023] [Indexed: 06/07/2023] Open
Abstract
Bronchiolitis, a common reason for infant hospitalisation in South Africa (SA), is caused by viral pathogens. Bronchiolitis is typically an illness of mild to moderate severity that occurs in well-nourished children. Hospitalised SA infants frequently have severe disease and/or coexisting medical conditions, and these cases of bronchiolitis may have bacterial co-infection that requires antibiotic therapy. However, the existence of widespread antimicrobial resistance in SA warrants the judicious use of antibiotics. This commentary describes: (i) common clinical pitfalls leading to an incorrect diagnosis of bronchopneumonia; and (ii) considerations for antibiotic therapy in hospitalised infants with bronchiolitis. If antibiotics are prescribed, the indication for their use should be clearly stated, and antibiotic therapy must be stopped promptly if investigations indicate that bacterial co-infection is unlikely. Until more robust data emerge, we recommend a pragmatic management strategy to inform antibiotic use in hospitalised SA infants with bronchiolitis in whom bacterial co-infection is suspected.
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Quantifying the Acute Care Costs of Neonatal Bacterial Sepsis and Meningitis in Mozambique and South Africa. Clin Infect Dis 2022; 74:S64-S69. [PMID: 34725702 PMCID: PMC8776306 DOI: 10.1093/cid/ciab815] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Sepsis and meningitis are among the leading causes of neonatal deaths in sub-Saharan Africa (SSA). Neonatal sepsis caused ~400 000 deaths globally in 2015, half occurring in Africa. Despite this, there are few published data on the acute costs of neonatal sepsis or meningitis, with none in SSA. METHODS We enrolled neonates admitted to 2 hospitals in South Africa and Mozambique between 16 April 2020 and 1 April 2021. In South Africa all cases were microbiologically confirmed, but in Mozambique both clinically suspected and microbiologically confirmed cases were included. Data were collected on healthcare resource use and length of stay, along with information on household expenditure and caregiving. We used unit costs of healthcare resources in local currencies to estimate healthcare provider costs per patient and costs per household. Results were converted to 2019 international dollars (I$). RESULTS We enrolled 11 neonates in Mozambique and 18 neonates in South Africa. Mean length of stay was 10 days (median, 9 [interquartile range {IQR}, 4-14) and 16 days (median, 15 [IQR, 13-18]), respectively. In Mozambique we estimated mean household costs of I$49.62 (median, 10.19 [IQR, 5.10-95.12]) and hospitalization costs of I$307.58 (median, 275.12 [IQR, 149.43-386.12]). In South Africa these costs were I$52.31 (median, 30.82 [IQR, 19.25-73.08]) and I$684.06 (median, 653.62 [IQR, 543.33-827.53]), respectively. CONCLUSIONS We found substantial costs associated with acute neonatal bacterial (all-cause) sepsis and meningitis in SSA. Our estimates will inform economic evaluations of interventions to prevent neonatal invasive bacterial infections.
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Pathophysiology and Imaging Findings of COVID-19 Infection: An Organ-system Based Review. Acad Radiol 2021; 28:595-607. [PMID: 33583712 PMCID: PMC7859715 DOI: 10.1016/j.acra.2021.01.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/12/2021] [Accepted: 01/21/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND COVID-19 commonly presents with upper respiratory symptoms; however, studies have shown that SARS-CoV-2 infection affects multiple organ systems. Here, we review the pathophysiology and imaging characteristics of SARS-CoV-2 infection in organ systems throughout the body and explore commonalities. OBJECTIVE Familiarity with the underlying pathophysiology and imaging characteristics is essential for the radiologist to recognize these findings in patients with COVID-19 infection. Though pulmonary findings are the most prevalent presentation, COVID-19 may have multiple manifestations and recognition of the extrapulmonary manifestations is especially important because of the potential serious and long-term effects of COVID-19 on multiple organ systems.
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Isoniazid Preventive Therapy and Pregnancy Outcomes in Women Living With Human Immunodeficiency Virus in the Tshepiso Cohort. Clin Infect Dis 2021; 71:1419-1426. [PMID: 31631221 PMCID: PMC7486841 DOI: 10.1093/cid/ciz1024] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 10/17/2019] [Indexed: 01/06/2023] Open
Abstract
Background Both pregnancy and human immunodeficiency virus (HIV) increase the risk of tuberculosis disease, which results in poor maternal, pregnancy, and infant outcomes. Isoniazid preventive therapy (IPT) reduces mortality among individuals living with HIV in high-burden settings but has recently been associated with adverse pregnancy outcomes when initiated during pregnancy. Methods In this secondary analysis, we used multivariable logistic regression to evaluate the association between IPT exposure and adverse pregnancy outcomes (fetal demise, prematurity, low birth weight, congenital anomaly) in pregnant women living with HIV enrolled as controls in the Tshepiso study, a prospective observational cohort of pregnant women living with HIV with and without tuberculosis disease in Soweto, South Africa, from 2011–2014. Results There were 151 women enrolled with known pregnancy outcomes; 69 (46%) reported IPT initiation during pregnancy. Of the 69 IPT-exposed women, 11 (16%) had an adverse pregnancy outcome compared with 23 (28%) IPT-unexposed women. The adjusted odds of having an adverse pregnancy outcome was 2.5 (95% confidence interval, 1.0–6.5; P = .048) times higher in IPT-unexposed women compared with IPT-exposed women after controlling for maternal age, CD4 count, viral load, antiretroviral regimen, body mass index, and anemia. Conclusions IPT exposure during pregnancy was not negatively associated with pregnancy outcomes after controlling for demographic, clinical, and HIV-related factors. These results provide some reassurance that IPT can be safely used in the second or third trimester of pregnancy. Additional research is needed to evaluate the safety of IPT and new short-course tuberculosis preventive therapies during pregnancy.
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Prevalence and risk factors for latent tuberculosis infection among household contacts of index cases in two South African provinces: Analysis of baseline data from a cluster-randomised trial. PLoS One 2020; 15:e0230376. [PMID: 32182274 PMCID: PMC7077873 DOI: 10.1371/journal.pone.0230376] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/26/2020] [Indexed: 01/16/2023] Open
Abstract
INTRODUCTION Household contacts of patients with active pulmonary tuberculosis (TB) often have latent TB infection, and are at risk of progression to disease. We set out to investigate whether index TB case HIV status was linked to a higher probability of latent TB infection among household contacts. MATERIALS AND METHODS Data were collected prospectively from participants in the intervention arm of a household cluster-randomised trial in two South Africa provinces (Mangaung, Free State, and Capricorn, Limpopo). In intervention group households, TB contacts underwent HIV testing and tuberculin skin testing (TST). TST induration was estimated at two cut-offs (≥5mm, ≥10mm). Multilevel Bayesian regression models estimated posterior distributions of the percentage of household contacts with TST induration ≥5mm and ≥10mm by age group, and compared the odds of latent TB infection by key risk factors including HIV status index case age and study province. RESULTS A total of 2,985 household contacts of 924 index cases were assessed, with most 2,725 (91.3%) undergoing TST. HIV prevalence in household contacts was 14% and 10% in Mangaung and Capricorn respectively. Overall, 16.8% (458/2,725) had TST induration of ≥5mm and 13.1% (359/2,725) ≥10mm. In Mangaung, children aged 0-4 years had a high TST positivity prevalence compared to their peers in Capricorn (22.0% vs. 7.6%, and 20.5% vs. 2.3%, using TST thresholds of ≥5mm and ≥10mm respectively). Compared to contacts from Capricorn, household contacts living in Mangaung were more likely to have TST induration ≥5mm (odds ratio [OR]: 3.08, 95% credibility interval [CI]: 2.13-4.58) and ≥10mm (OR: 4.52, 95% CI: 3.03-6.97). There was a 90% and 92% posterior probability that the odds of TST induration ≥5mm (OR: 0.79, 95% CI: 0.56-1.14) and ≥10mm (OR: 0.77, 95% CI: 0.53-1.10) respectively were lower in household contacts of HIV-positive compared to HIV-negative index cases. CONCLUSIONS High TST induration positivity, especially among young children and people living in Mangaung indicates considerable TB transmission despite high antiretroviral therapy coverage. Household contact of HIV-positive index TB cases were less likely to have evidence of latent TB infection than contacts of HIV-negative index cases.
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Poor Obstetric and Infant Outcomes in Human Immunodeficiency Virus-Infected Pregnant Women With Tuberculosis in South Africa: The Tshepiso Study. Clin Infect Dis 2019; 66:921-929. [PMID: 29028970 DOI: 10.1093/cid/cix851] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 09/21/2017] [Indexed: 11/13/2022] Open
Abstract
Background Before the wide availability of antiretroviral therapy (ART), tuberculosis and human immunodeficiency virus (HIV) disease among pregnant women resulted in poor maternal and neonatal outcomes, including high rates of mother-to-child transmission of both HIV and tuberculosis. We aimed to describe the impact of tuberculosis among HIV-infected mothers on obstetric and infant outcomes in a population with access to ART. Methods In this prospective cohort study, we followed up HIV-infected pregnant women with or without tuberculosis disease from January 2011 through January 2014 in Soweto, South Africa. Two controls were enrolled for each case patient, matched by enrollment time, maternal age, gestational age, and planned delivery clinic and followed up for 12 months after delivery. Results We recruited 80 case patients and 155 controls, resulting in 224 live-born infants. Infants of mothers with HIV infection and tuberculosis disease had a higher risk of low birth weight (20.8% vs 10.7%; P = .04), prolonged hospitalization at birth (51% vs 16%; P < .001), infant death (68 vs 7 deaths per 1000 births; P < .001), and tuberculosis disease (12% vs 0%; P < .001) despite appropriate maternal therapy and infant tuberculosis preventive therapy. HIV transmission was higher among these infants (4.1% vs 1.3%; P = .20), though this difference was not statistically significant. Obstetric outcomes in coinfected women were also poorer with higher risks of maternal hospitalization (25% vs 11%; P = .005) and preeclampsia (5.5% vs 0.7%; P = .03). Conclusions Tuberculosis in HIV coinfected pregnant women remains a significant threat to the health of both mothers and infants. Improving tuberculosis prevention and early diagnosis among pregnant women is critical.
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Communicating the External Beam Radiation Experience (CEBRE): A Novel Graphic Narrative Patient Education Tool. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Structural and microstructural interpretations of Zn-doped biocompatible bone-like carbonated hydroxyapatite synthesized by mechanical alloying. J Appl Crystallogr 2015. [DOI: 10.1107/s1600576714026119] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Single-phase nanocrystalline biocompatible Zn-dopedA-type carbonated hydroxyapatite (A-cHAp) powder has been synthesizedviamechanical alloying of a stoichiometric mixture of CaCO3, CaHPO4·2H2O and ZnO powders in open air at room temperature by 10 h of milling. TheA-type carbonation in HAp (A-cHAp) is confirmed by Fourier transform IR analysis. The structural and microstructural parameters of the as-milled powders are revealed by Rietveld powder structure refinement analysis and transmission electron microscopy. Zn substitution along with mechanical alloying causes partial amorphization of crystallineA-cHAp, analogous to native bone mineral. Zn2+cations substitute into the ninefold-coordinated Ca2+sites in theA-cHAp unit cell. An assay test using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] reveals a high percentage of cell viability and hence confirms the biocompatibility of the sample. The overall results indicate that the processedA-cHAp has a chemical composition very close to that of natural biological apatite.
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Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure. Dalton Trans 2015; 44:20087-97. [DOI: 10.1039/c5dt03398e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Mn substitution reduces Ca2/Mn–O bond lengths leading to structural changes in the A-cHAp lattice.
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Structural and microstructural characterizations of nanocrystalline hydroxyapatite synthesized by mechanical alloying. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 33:2891-8. [DOI: 10.1016/j.msec.2013.03.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 02/18/2013] [Accepted: 03/05/2013] [Indexed: 10/27/2022]
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Emphysematous pyelonephritis: a case report series of four patients with review of literature. Ren Fail 2010; 31:597-601. [PMID: 19839858 DOI: 10.1080/08860220903003396] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Emphysematous pyelonephritis (EPN) is an acute necrotizing infection with gas presence in the kidney, perinephric space, and/or urinary collecting system that carries a bad prognosis. Some clinical conditions predispose to this entity, such as diabetes mellitus, urinary tract obstruction, and immune-incompetence. Immediate resuscitation, broad-spectrum antibiotics, percutaneous and surgical drainage, and emergent and delayed nephrectomy are therapeutic options that should be applied in a timely fashion. We report our experience of four patients with EPN. Two of the patients were kidney transplant recipients, one patient had bilateral urolithiasis, and one patient was an elderly patient with debilitated general condition and an abdominal mass that could not be defined. Late transplant nephrectomy was performed in one patient, and three patients were treated conservatively. Three patients died, including the patient who had transplant nephrectomy. One patient who presented with lithiasis showed a remarkable recovery with conservative management. The bacteria involved were E. Coli and a resistant Klebsiella. We conclude that EPN is a life-threatening condition that carries a bad prognosis. Early diagnosis is essential for a positive outcome. Therapeutic measures should be applied immediately after diagnosis. An aggressive approach including nephrectomy may be emergently required.
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Designing and Testing of an Effective Oil-in-Water Microemulsion Drug Delivery System forIn VivoApplication. Drug Deliv 2008; 12:267-73. [PMID: 16188725 DOI: 10.1080/10717540500176373] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The phase behavior of a new psedoternary system of clove oil/Tween 20 has been studied. Several compositions from the single-phase region were selected and their stability toward time, temperature, and electrolytes has been examined. A particular composition(clove oil/Tween 20/water as 5/30/65) was chosen as the drug delivery system from the clear oil-in-water zone of the pseudoternary system. The droplet dimension and the polydispersity state of the particular composition was determined by dynamic light scattering. A bioactive compound quarcetin was encapsulated in the vehicle. The efficacy of the drug in the vehicle was examined against leishmaniasis in hamster models. The hepatotoxicity of the vehicle (o/w microemulsion) with and without the drug quarcetin was examined by estimating serum alkaline phosphatase, glutamate pyruvate transaminase, urea, and creatinine.
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The pathogen recognition sensor, NOD2, is variably expressed in patients with pulmonary tuberculosis. BMC Infect Dis 2007; 7:96. [PMID: 17705850 PMCID: PMC2018706 DOI: 10.1186/1471-2334-7-96] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 08/16/2007] [Indexed: 11/21/2022] Open
Abstract
Background NOD2, an intracellular pathogen recognition sensor, modulates innate defences to muropeptides derived from various bacterial species, including Mycobacterium tuberculosis (MTB). Experimentally, NOD2 attenuates two key putative mycobactericidal mechanisms. TNF-α synthesis is markedly reduced in MTB-antigen stimulated-mononuclear cells expressing mutant NOD2 proteins. NOD2 agonists also induce resistance to apoptosis, and may thus facilitate the survival of MTB in infected macrophages. To further define a role for NOD2 in disease pathogenesis, we analysed NOD2 transcriptional responses in pulmonary leucocytes and mononuclear cells harvested from patients with pulmonary tuberculosis (PTB). Methods We analysed NOD2 mRNA expression by real-time polymerase chain-reaction in alveolar lavage cells obtained from 15 patients with pulmonary tuberculosis and their matched controls. We compared NOD2 transcriptional responses, in peripheral leucocytes, before and after anti-tuberculous treatment in 10 patients. In vitro, we measured NOD2 mRNA levels in MTB-antigen stimulated-mononuclear cells. Results No significant differences in NOD2 transcriptional responses were detected in patients and controls. In some patients, however, NOD2 expression was markedly increased and correlated with toll-like-receptor 2 and 4 expression. In whole blood, NOD2 mRNA levels increased significantly after completion of anti-tuberculosis treatment. NOD2 expression levels did not change significantly in mononuclear cells stimulated with mycobacterial antigens in vitro. Conclusion There are no characteristic NOD2 transcriptional responses in PTB. Nonetheless, the increased levels of NOD2 expression in some patients with severe tuberculosis, and the increases in expression levels within peripheral leucocytes following treatment merit further studies in selected patient and control populations.
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Tolerance and Safety of Different Concentrations of Chlorhexidine for Peripartum Vaginal and Infant Washes: HIVNET 025. J Acquir Immune Defic Syndr 2004; 35:138-43. [PMID: 14722445 PMCID: PMC2753236 DOI: 10.1097/00126334-200402010-00006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND There is a continuing need to evaluate sustainable interventions for prevention of mother-to-child transmission (MTCT) of HIV type 1. We evaluated different concentrations (0.25%, 1%, and 2%) of chlorhexidine (CHX) for perinatal maternal and infant washes to identify the maximum tolerable concentration of CHX for such an intervention. METHODS Women were enrolled during their third trimester at the maternity unit of the Chris Hani Baragwanath Hospital in Soweto, South Africa, and perinatal maternal and infant washes were completed. Subjective maternal symptoms as well as infant examinations were used to assess tolerability of the washes. RESULTS The 0.25% concentration of CHX was well tolerated by the mothers (n = 29). Ten of 79 women (13%) with 1% CHX washes complained of mild vaginal area burning or itching, and washes were stopped in 5 (6%). Twenty-three of 75 women (31%) in the 2% CHX wash group had subjective complaints, and the washes were stopped in 12 (16%). There were no clinical indications of toxicity of the CHX washes among infants. CONCLUSION A 1% solution of CHX appears to be a safe and tolerable concentration of CHX for consideration in an MTCT prevention trial.
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Abstract
BACKGROUND AND AIMS Genetic variation in NOD2 has been associated with susceptibility to Crohn's disease (CD) and specifically with ileal involvement. The reason for the unique association of NOD2 mutations with ileal disease is unclear. To identify a possible link, we tested expression of NOD2 in intestinal tissue of CD patients and controls. PATIENTS AND METHODS Fifty five specimens of ileum or colon from 21 CD patients, seven ulcerative colitis (UC) patients, and five controls with pathology other than CD or UC were stained for NOD2 using an immunoperoxidase method. RESULTS Using a monoclonal antibody against NOD2 developed in our laboratory, we detected uniform expression of NOD2 in terminal ileum Paneth cells from controls and patients as well as in metaplastic Paneth cells in the colon. Mechanical purification showed enriched expression of NOD2 mRNA in ileal crypts. In Paneth cells, NOD2 was located in the cytosol in close proximity to the granules that contain antimicrobial peptides. We detected minimal NOD2 in the villous epithelium of the ileum or in the colonic epithelium from both CD patients and controls. CONCLUSIONS These results suggest a role for NOD2 in the regulation of Paneth cell mediated responses against intestinal bacteria and a plausible mechanism to explain the selective association of NOD2 mutations with ileal disease. The impaired capacity of CD associated mutations to sense luminal bacteria may result in increased susceptibility to certain gut microbes.
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Abstract
BACKGROUND & AIMS The NOD2 gene, which is strongly associated with susceptibility to Crohn's disease (CD) of the terminal ileum, interacts with bacterial lipopolysaccharide (LPS), inducing cellular activation. However, the mechanisms by which NOD2 mutations cause terminal ileitis are unknown, and NOD2 is expressed most highly by peripheral blood monocytes, which are distributed ubiquitously and readily respond to LPS via cell-surface receptors. Paneth cells on the other hand, are most numerous in the terminal ileum, are critically important in enteric antibacterial defense, and respond to LPS through as yet undefined pathways. We therefore determined if these specialized intestinal epithelial cells also expressed the NOD2 gene. METHODS In situ hybridization, immunohistochemistry, and laser-capture microdissection were used to determine RNA and protein expression in tissue sections, and real-time reverse-transcription polymerase chain reaction (RT-PCR) was used to quantitate gene expression in intestinal epithelial cells and peripheral blood mononuclear cells. RESULTS NOD2 was detected readily in monocytes, but not in mature macrophages in the lamina propria or within granulomas, and levels declined as monocytes differentiated into macrophages in vitro, so that Caco-2 cells expressed more NOD2 mRNA than macrophages. NOD2 mRNA was enriched in crypts compared with villi, and in situ, Paneth cells were the most prominent cells expressing NOD2 in normal and CD-affected intestinal tissue, where they also strongly expressed tumor necrosis factor alpha (TNFalpha) RNA. CONCLUSIONS The NOD2 gene product is most abundant in Paneth cells in the terminal ileum, which could therefore play a critical and hitherto unrecognized role in the pathogenesis of NOD2-associated CD.
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Delivery in vivo of 14-deoxy-11-oxoandrographolide, an antileishmanial agent, by different drug carriers. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 2003; 40:169-174. [PMID: 22900306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
An antileishmanial compound, 14-deoxy-11-oxo-andrographolide, a derivative of andrographlide, isolated from the Indian medicinal plant Andrographis paniculata was evaluated for efficacy in free form and in different vesicular delivery modes on hamster model of Leishmaniasis. The subcutaneous injection of free drug reduced the spleen parasite load by 39%, whereas for drug incorporated in liposomes, niosomes and microspheres, reductions in the parasite load were 78%, 91% and 59%, respectively. Moreover, the drug in various delivery modes, particularly in liposomal and niosomal forms, showed no apparent immediate toxicity. Although an inverse linear relationship between the size of carriers and per cent efficacy in reduction of spleen parasite load was established, involvement of other factors such as drug release profiles or rates remains an open question. Because of greater efficacy and lesser toxicity, liposomal, niosomal and possibly microsphere-incorporated 14-deoxy-11-oxo-andrographolide might have clinical application to combat visceral Leishmaniasis.
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Abstract
Cardiac myxomas are rarely diagnosed in children, and biatrial tumors are an unusual presentation in any age group. An 8-year-old boy with massive biatrial cardiac myxomas, who presented in acute cardiogenic shock with no preceding cardiac symptomatology, is reported.
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Hepatitis B vaccination in Tauranga. THE NEW ZEALAND MEDICAL JOURNAL 1988; 101:518. [PMID: 2970024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Acute mountain sickness and acetazolamide. THE NEW ZEALAND MEDICAL JOURNAL 1988; 101:463. [PMID: 3399193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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