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1.
Infect Prev Pract ; 3(2): 100139, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34316578

RESUMO

PPE is an integral part of reducing transmission of COVID-19. We assessed a 5-week pilot project of utilising health science student volunteers as PPE coaches in the adult and paediatric emergency department (ED) during the pandemic. PPE coaches were provided with training, PPE checklist, area for written observations, and feedback surveys. Overall, correct PPE use improved over time. Coaches felt safe, that training was adequate, and part of the team. Factors that contributed to project effectiveness included institutional support, role clarification, and continuous feedback from staff. Our findings support the utilisation of students in IPC projects.

2.
J Epidemiol Community Health ; 57(5): 361-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12700221

RESUMO

STUDY OBJECTIVE: This study investigated which risk factors might explain social inequalities in both depressive symptoms and physical functioning and whether a common set of risk factors might account for the association between depressive symptoms and physical functioning. DESIGN: A longitudinal prospective occupational cohort study of female and male civil servants relating risk factors at baseline (phase 1: 1985-8) to employment grade gradients in depressive symptoms and physical functioning at follow up (phase 5: 1997-9). Analyses include the 7270 men and women who participated at phase 5. SETTING: Whitehall II Study: 20 London based white collar civil service departments. PARTICIPANTS: Male and female civil servants, 35-55 years at baseline. MAIN RESULTS: Depressive symptoms were measured by a subscale of items from the 30 item General Health Questionnaire. Physical functioning was measured by a subscale of the SF-36. Employment grade was used as a measure of socioeconomic position as it reflects both income and status. The grade gradient in depressive symptoms was entirely explained by risk factors including work characteristics, material disadvantage, social supports, and health behaviours. These risk factors only partially explained the gradient in physical functioning. The correlation between depressive symptoms and physical functioning was reduced by adjustment for risk factors and baseline health status but not much of the association was explained by adjustment for risk factors. Among women, the association between depression and physical functioning was significantly stronger in the lower grades both before and after adjustment for risk factors and baseline health. For women, there was only a significant grade gradient in depressive symptoms among those reporting physical ill health. CONCLUSIONS: Some risk factors contribute jointly to the explanation of social inequalities in mental and physical health although their relative importance differs. Work is most important for inequalities in depressive symptoms in men, and work and material disadvantage are equally important in explaining inequalities in depressive symptoms in women while health behaviours are more important for explaining inequalities in physical functioning. These risk factors did not account for the association between mental health and physical health or the greater comorbidity seen in women of lower socioeconomic status. The risk of secondary psychological distress among those with physical ill health is greater in the low employment grades.


Assuntos
Depressão/etiologia , Nível de Saúde , Classe Social , Adulto , Comorbidade , Depressão/epidemiologia , Depressão/fisiopatologia , Emprego , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Londres/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Apoio Social , Inquéritos e Questionários
3.
J Immunol ; 167(5): 2452-5, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11509582

RESUMO

Systemic lupus erythematosus (SLE) is a common, potentially fatal, non-organ-specific autoimmune disorder. Immune complex-mediated kidney disease is the major cause of mortality. Apoptotic cells in the epidermis are a possible source of self Ags, and apoptosis of endothelial cells and lymphocytes is thought to contribute to end-organ damage. We have previously shown that female transgenic mice expressing IFN-gamma in the epidermis develop inflammatory skin disease and features of SLE that have striking parallels with the human condition. We have now tested the effects of a pan-caspase inhibitor, carbobenzoxy-valyl-alanyl-aspartyl-(beta-o-methyl)-fluoromethylketone, on disease progression. Daily s.c. administration of carbobenzoxy-valyl-alanyl-aspartyl-(beta-o-methyl)-fluoromethylketone to female transgenic mice over a 3-wk period resulted in significant amelioration of both glomerular and interstitial renal damage, independent of the effects on autoantibody levels or skin inflammation. We propose that apoptosis inhibitors could be beneficial in the treatment of human SLE.


Assuntos
Clorometilcetonas de Aminoácidos/uso terapêutico , Inibidores de Caspase , Inibidores de Cisteína Proteinase/uso terapêutico , Nefrite Lúpica/tratamento farmacológico , Animais , Anticorpos Antinucleares/sangue , Autoanticorpos/sangue , Modelos Animais de Doenças , Feminino , Histonas/imunologia , Humanos , Interferon gama/genética , Rim/patologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Nefrite Lúpica/enzimologia , Nefrite Lúpica/genética , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Pele/patologia
5.
Kidney Int ; 59(6): 2069-72, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11380808

RESUMO

BACKGROUND: How red cells enter the urinary filtrate in most cases of hematuria of glomerular origin has remained a mystery despite the frequent ultrastructural examination of renal biopsy material. METHODS: Serial sections of glutaraldehyde-fixed, resin-embedded material from a case of sporadic microhematuria were examined by transmission electron microscopy when the site of a red cell traversing the glomerular capillary wall was fortuitously discovered on routine examination. RESULTS: The red cell assumed a dumbbell shape and traversed a localized gap 2.25 microm in diameter in the glomerular endothelium and basement membrane. Serial sections suggested a transcellular route. Apart from the thinning of the basement membrane (167 nm), there were no other generalized abnormalities. CONCLUSION: Red cells can traverse through gaps in the glomerular capillary walls to gain access to Bowman's space. This may be the origin of glomerular hematuria in common noninflammatory forms of glomerular disease, including thin basement membrane nephropathy.


Assuntos
Movimento Celular , Eritrócitos/citologia , Hematúria/patologia , Hematúria/fisiopatologia , Glomérulos Renais/patologia , Adulto , Membrana Basal/patologia , Biópsia , Capilares/patologia , Capilares/ultraestrutura , Eritrócitos/ultraestrutura , Feminino , Humanos , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/ultraestrutura , Microscopia Eletrônica , Nefrite Hereditária/patologia , Nefrite Hereditária/fisiopatologia
6.
Soc Sci Med ; 52(10): 1501-16, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11314847

RESUMO

This paper explores the dynamics between poverty and exclusion; neighbourhood, and health and well being by considering the role of social networks and social capital in the social processes involved. It is based on qualitative research taking two deprived areas as exemplary case studies, and involving depth interviews with residents. Neighbourhood influences on networks and social capital were explored, network typologies developed reflecting structural and cultural aspects of individual's networks, and pathways implicated in health effects considered. The complexity of social capital is addressed. The role of three factors in influencing social networks and social capital are demonstrated: neighbourhood characteristics and perceptions; poverty and social exclusion, and social consciousness. Perceptions of inequality could be a source of social capital as well as demoralisation. Different network structures-dense and weak, homogeneous and heterogeneous- were involved in the creation of social capital and had implications for well being. Coping, enjoyment of life and hope are identified as benefits. Although participation in organisations was confirmed as beneficial, it is suggested that today's heterogeneous neighbourhoods also require regenerated local work opportunities to develop bridging ties necessary for the genesis of inclusive social capital and better health. Despite the capacity of social capital to buffer its harsher effects, the concept is not wholly adequate for explaining the deleterious effects of poverty on health and well being.


Assuntos
Atitude Frente a Saúde , Redes Comunitárias/organização & administração , Participação da Comunidade , Nível de Saúde , Relações Interpessoais , Pobreza , Apoio Social , Estresse Psicológico/prevenção & controle , Estresse Psicológico/psicologia , Adaptação Psicológica , Adulto , Idoso , Anomia (Social) , Crime/psicologia , Crime/estatística & dados numéricos , Medo , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Moral , Avaliação das Necessidades , Pobreza/psicologia , Pobreza/estatística & dados numéricos , Distância Psicológica , Qualidade de Vida , Estresse Psicológico/etiologia , Inquéritos e Questionários
7.
QJM ; 94(4): 187-93, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11294961

RESUMO

There is a high incidence of end-stage renal failure (ESRF) of undetermined cause in the Indo-Asian population of the UK. We studied patients presenting from the district of Brent and Harrow, which has a large Indo-Asian community, and whose renal services are largely provided by our centre. The diagnosis and ethnicity of patients starting renal replacement therapy and/or undergoing renal biopsy were collated. The incidences of ESRF, rates of renal biopsy and underlying diagnoses were calculated for Indo-Asians and Caucasians. Requirement for renal replacement therapy in Indo-Asians presenting to our centre from Brent and Harrow was 221/10(6)/year; no underlying diagnosis was identified in 77/10(6)/year. Renal biopsy rate in these patients was 456/10(6)/year, and the diagnostic categories significantly over-represented compared to Caucasians were: hypertension and ischaemia, focal segmental glomerulosclerosis (FSGS), idiopathic interstitial nephritis (IIN), diabetic nephropathy, minor glomerular abnormality, lupus nephritis and non-specific advanced chronic renal disease (p<0.001). The first three of these had a combined incidence of 135/10(6)/year in Indo-Asians and 31/10(6)/year in Caucasians. ESRF of undetermined cause is common in UK Indo-Asians, as is requirement for renal biopsy. Hypertension with ischaemia, FSGS and IIN are over-represented in the Indo-Asian population, and should be targeted for early diagnosis and treatment in this group.


Assuntos
Falência Renal Crônica/etnologia , Adulto , Idoso , Ásia/etnologia , Biópsia/estatística & dados numéricos , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/etnologia , Nefropatias Diabéticas/terapia , Glomerulosclerose Segmentar e Focal/complicações , Glomerulosclerose Segmentar e Focal/etnologia , Glomerulosclerose Segmentar e Focal/terapia , Humanos , Hipertensão/complicações , Hipertensão/etnologia , Hipertensão/terapia , Incidência , Índia/etnologia , Falência Renal Crônica/etiologia , Falência Renal Crônica/terapia , Pessoa de Meia-Idade , Nefrite Intersticial/complicações , Nefrite Intersticial/etnologia , Nefrite Intersticial/terapia , Terapia de Substituição Renal/estatística & dados numéricos , Reino Unido/epidemiologia
8.
Virchows Arch ; 436(6): 567-73, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10917170

RESUMO

Cell death is central to many physiological and pathological processes. As tissue reactions to the two forms of cell death, necrosis and apoptosis, differ, it is critical to distinguish between them. Although ultrastructure is still the definitive means of assessing this, there are very few in vivo studies. Administration of anti-Thy 1 antibody in rats is a model of acute glomerular mesangial cell death due to their expression of the Thy 1.1 epitope. The nature of this process is unclear; apoptosis was suggested from early morphological studies and recent in vitro effects of anti-Thy 1.1 antibody. We have re-examined the changes by electron microscopy, and identified a process of cell necrosis starting within 30 min of anti-Thy 1.1 antibody administration. Although there was chromatin condensation, the necrotic features distinctive from apoptosis were: loss of nuclear membranes, cell swelling and degeneration of cytoplasmic organelles, with liberation of chromatin and organelles into the interstitium causing acute inflammation without phagocytic uptake of apoptotic bodies. These findings accord with the known complement dependence of this model. Ultrastructure is a valuable means of differentiating between in vivo necrosis and apoptosis and this is important for understanding the pathogenesis of injury and subsequent tissue responses.


Assuntos
Anticorpos Monoclonais , Mesângio Glomerular/patologia , Glomerulonefrite/patologia , Isoanticorpos , Necrose , Animais , Apoptose/imunologia , Endotélio/patologia , Endotélio/ultraestrutura , Mesângio Glomerular/imunologia , Mesângio Glomerular/ultraestrutura , Glomerulonefrite/induzido quimicamente , Glomerulonefrite/imunologia , Macrófagos/imunologia , Masculino , Microscopia Eletrônica , Neutrófilos/imunologia , Ratos , Fatores de Tempo
9.
Exp Nephrol ; 8(3): 128-34, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10810229

RESUMO

Arginase metabolizes L-arginine to L-ornithine and urea. Two arginase isoforms, AI (liver arginase) and AII (ubiquitously expressed, functions unknown), have been identified. It is clear that arginases potentially have important roles in addition to urea generation for high concentrations are present at inflammatory sites. Regulation occurs through cytokines, substrate competition and products of nitric oxide (NO) metabolism. The functions of arginases at inflammatory sites are unknown, but may include regulation of apoptosis and NO production and generation of structural and cellular protein precursors. In glomerulonephritis there is increased arginase activity in nephritic glomeruli following a pattern similar to that in wound healing. The level can be further increased by NO inhibition suggesting substrate competition. The potential sources in the inflamed glomerulus include infiltrating leucocytes and mesangial cells, and the predominant isoform expressed is AI (AII predominates under physiological conditions). The recent identification of different isoforms of arginase has been an important step towards understanding the significance of arginase activity in glomerulonephritis.


Assuntos
Arginase/metabolismo , Glomerulonefrite/enzimologia , Animais , Arginase/fisiologia , Mesângio Glomerular/metabolismo , Glomerulonefrite/fisiopatologia , Humanos , Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/metabolismo
10.
Clin Exp Immunol ; 118(2): 309-14, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10540196

RESUMO

Increased NO synthesis, due to inducible NO synthase (iNOS) activity, is found in macrophage-associated glomerulonephritis. Little is known about NO in neutrophil-dependent immune complex inflammation, and its role remains controversial. We therefore studied early phase heterologous nephrotoxic nephritis (HNTN) induced in rats by nephrotoxic globulin and the effects of selective iNOS inhibition of this model. At 2 h of the model iNOS mRNA was induced and nitrite (NO-2) was generated in glomeruli incubated ex vivo (5.2 +/- 1.0 nmol/2000 glomeruli per 24 h). There were 14.7 +/- 2.2 polymorphonuclear neutrophils (PMN)/glomerulus (normal controls 0.1 +/- 0.1). At 8 h urinary protein was 69 +/- 15.3 (normal controls 0. 6 +/- 0.2 mg/24 h). Peritoneal PMN expressed iNOS and produced significant NO-2 (basal 11.2 +/- 0.3 nmol/106 cells per 24 h). Selective iNOS inhibition with L-N6-(1-iminoethyl)-lysine (L-NIL) in vitro inhibited nephritic glomerular and PMN NO-2 synthesis. In HNTN L-NIL in vivo significantly suppressed elevated plasma NO-2/NO-3 levels (representative experiment: 17 +/- 2 microM, untreated 40 +/- 4 microM, P = < 0.01, normal control 18 +/- 2 microM). This inhibition did not affect leucocyte infiltration into glomeruli or induce thrombosis. There was no consistent effect on proteinuria. This is the first demonstration of glomerular iNOS induction and high output NO production in the acute phase of PMN-dependent acute immune complex glomerulonephritis. Selective iNOS inhibition does not affect the primary mechanism of injury (leucocyte infiltration) in this model.


Assuntos
Glomerulonefrite/imunologia , Neutrófilos/imunologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Animais , Indução Enzimática/imunologia , Inibidores Enzimáticos/metabolismo , Glomerulonefrite/induzido quimicamente , Glomerulonefrite/enzimologia , Complexo Antigênico da Nefrite de Heymann , Glomérulos Renais/enzimologia , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Lisina/análogos & derivados , Lisina/farmacologia , Masculino , Glicoproteínas de Membrana/imunologia , Neutrófilos/enzimologia , Neutrófilos/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Endogâmicos Lew
11.
J Immunol ; 162(12): 7241-8, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10358171

RESUMO

We have previously shown that female transgenic mice expressing IFN-gamma in the epidermis, under the control of the involucrin promoter, develop inflammatory skin disease and a form of murine lupus. To investigate the pathogenesis of this syndrome, we generated female IFN-gamma transgenic mice congenitally deficient in either alpha beta or gamma delta T cells. TCR delta-/- transgenics continued to produce antinuclear autoantibodies and to develop severe kidney lesions. In contrast, TCR beta-/- IFN-gamma transgenic mice failed to produce antinucleosome, anti-dsDNA, or antihistone autoantibodies, and kidney disease was abolished. Both alpha beta- and gamma delta-deficient transgenics continued to develop IFN-gamma-associated skin disease, lymphadenopathy, and splenomegaly. The data show that the autoantibody-mediated pathology of murine lupus in IFN-gamma transgenic mice is completely alpha beta T cell dependent and that gamma delta T cells cannot drive autoantibody production. These results imply that production of antinuclear autoantibodies in IFN-gamma transgenic animals is Ag driven, and we identified clusters of apoptotic cells in the epidermis of the mice as a possible source of self Ags. Our findings emphasize the relevance of this murine lupus model to the human disease.


Assuntos
Nefrite Lúpica/etiologia , Nefrite Lúpica/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Subpopulações de Linfócitos T/imunologia , Animais , Anticorpos Antinucleares/biossíntese , Apoptose/imunologia , Autoanticorpos/biossíntese , Autoanticorpos/sangue , DNA/imunologia , Dermatite/genética , Dermatite/imunologia , Dermatite/patologia , Feminino , Histonas/imunologia , Imunoglobulina G/biossíntese , Interferon gama/genética , Nefrite Lúpica/genética , Nefrite Lúpica/patologia , Doenças Linfáticas/genética , Doenças Linfáticas/imunologia , Linfopenia/genética , Linfopenia/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/deficiência , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/fisiologia , Pele/patologia , Esplenomegalia/genética , Esplenomegalia/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia
12.
Semin Nephrol ; 19(3): 277-87, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10226334

RESUMO

The normal glomerulus expresses constitutive nitric oxide (NO) synthesis. Increased NO from inducible nitric oxide synthase (iNOS) occurs in acute immune glomerulonephritis (GN), in which rapid induction probably depends on local cytokines and/or oxygen radical production. Although intrinsic glomerular cells possess iNOS, in acute GN, a leukocyte origin for iNOS activity is most evident. Although NO potentially could be toxic or protective, there is as yet no clear understanding of how it affects the pathogenesis of GN. This may depend on the amount present, which in turn depends on NOS gene regulation, simultaneous production of other radicals, and the activity of arginase. High-output NO has been implicated in injury in only one model of GN, and no effect of iNOS knockout found in another. The concept is emerging that constitutive NO is critical for offsetting increased vasoconstriction in the injured glomerulus.


Assuntos
Glomerulonefrite/etiologia , Óxido Nítrico/fisiologia , Animais , Arginina/metabolismo , Humanos , Lipopolissacarídeos/toxicidade , Nefrite Lúpica/etiologia , Camundongos , Camundongos Knockout , Óxido Nítrico Sintase/fisiologia , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III
13.
Exp Nephrol ; 7(1): 26-34, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-9892811

RESUMO

Thy 1 glomerulonephritis (GN) is a rat model of complement-dependent immune mesangial injury with induced glomerular nitric oxide (NO) synthesis. To examine mechanisms of inducible nitric oxide synthase (iNOS) induction, we studied the effects of treatment with the antioxidant N-acetyl-cysteine (NAC) and soluble complement receptor 1 (sCR1). Thy 1 GN was induced by intravenous anti-Thy 1 antibody. Glomeruli were isolated and kidney tissue taken from 30 min to 24 h after induction. Nitrite (NO-2) synthesis, luminol chemiluminescence for reactive oxygen species (ROS), and iNOS and cytokine mRNA were assayed in isolated glomeruli. Mesangial injury (mesangiolysis) and leucocyte infiltration were quantitated on tissue sections. NAC (i.p. 1,000 mg/kg, 1 h prior to anti-Thy 1) reduced glomerular NO-2 synthesis (3.5 +/- 0.66 vs. untreated 8.2 +/- 1.1, p = 0.02), and iNOS mRNA expression, and abolished enhanced chemiluminescence. In vitro incubation of nephritic glomeruli with 20 mM NAC also suppressed nitrite production (4.7 +/- 0.8 vs. untreated 12.2 +/- 0. 7 nmol NO-2/2,000 glomeruli/48 h, p = 0.003), and chemiluminescence. In NAC-treated animals, neutrophil infiltration (0.5 +/- 0 vs. untreated 9.6 +/- 1.6 glomerulus, p = 0.0005), and macrophage infiltration (1.7 +/- 0.4 vs. untreated 12.0 +/- 0.1, p = 0.006) were abolished, and mesangiolysis was significantly reduced (45.9 +/- 1.3 vs. untreated 34.4 +/- 2.1 cells/glomerulus, p = 0.009). NAC did not inhibit anti-Thy 1 antibody deposition. C1q was unaffected, but C3 was reduced. sCR1 treatment prevented iNOS mRNA induction, the enhanced chemiluminescence, and the neutrophil infiltration at 1 h. IL-1beta and TNFalpha mRNAs were not affected by either NAC or sCR1. These results show that NAC inhibits iNOS induction and NO synthesis in this model, and suppresses ROS synthesis and injury. They suggest that complement-dependent ROS generation is the critical initiating event that follows fixation of anti-Thy 1 antibody.


Assuntos
Proteínas do Sistema Complemento/metabolismo , Glomerulonefrite/imunologia , Glomerulonefrite/metabolismo , Óxido Nítrico Sintase/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Antígenos Thy-1 , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Sequência de Bases , Primers do DNA/genética , Modelos Animais de Doenças , Indução Enzimática , Glomerulonefrite/tratamento farmacológico , Técnicas In Vitro , Interleucina-1/biossíntese , Interleucina-1/genética , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew , Receptores de Complemento/administração & dosagem , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética
14.
Biochem Biophys Res Commun ; 247(1): 84-7, 1998 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9636659

RESUMO

Previous studies have shown high arginase activity at inflammatory sites. Arginase converts L-arginine to L-ornithine, sharing a common substrate with nitric oxide synthase. It exists as two isoforms, AI and AII. While the function of liver arginase (AI) in ureagenesis has been defined, the role and isoform of arginase in cells without a complete urea cycle are unknown. We therefore determined arginase isoform mRNA expression in glomerular acute immune complex inflammation, and its cultured constituent cells. AI was induced in nephritic glomeruli, and in mesangial cells stimulated with IL-4 and cAMP, and was present in elicited neutrophils and macrophages. AII was constitutively expressed. Our data strongly suggest that AI, thought to be restricted to the liver, accounts for high arginase activity at inflammatory sites where it may limit high output nitric oxide production and generate polyamines and proline essential for cell proliferation and matrix production. This identification of AI in inflamed tissue is an important step for understanding the consequences of increased arginase activity.


Assuntos
Arginase/biossíntese , Doenças do Complexo Imune/enzimologia , Doenças do Complexo Imune/patologia , Regulação para Cima/imunologia , Doença Aguda , Animais , Mesângio Glomerular/enzimologia , Glomerulonefrite/enzimologia , Glomerulonefrite/patologia , Inflamação/enzimologia , Inflamação/imunologia , Isoenzimas/biossíntese , Glomérulos Renais/enzimologia , Glomérulos Renais/patologia , Macrófagos/enzimologia , Masculino , Neutrófilos/enzimologia , Ratos , Ratos Endogâmicos Lew
15.
Am J Physiol ; 274(3): F473-80, 1998 03.
Artigo em Inglês | MEDLINE | ID: mdl-9530263

RESUMO

Arginase shares a common substrate, L-arginine, with nitric oxide synthase (NOS). Both enzymes are active at inflammatory sites. To understand regulation of arginase and its relationship to nitric oxide (NO) production, we studied effects of NG-hydroxy-L-arginine (HOArg) and interleukin-4 (IL-4) on urea and NO2- synthesis by glomeruli during rat immune glomerulonephritis and compared these with macrophages and glomerular mesangial cells (MC). In nephritic glomeruli, elicited macrophages, and MC stimulated with IL-1 and adenosine 3',5'-cyclic monophosphate agonists, increased arginase and induced NOS activity was found. Urea production was inhibited by HOArg and increased by IL-4. NO inhibition [NG-monomethyl-L-arginine (L-NMMA)] increased arginase activity in nephritic glomeruli and macrophages but not MC. NO2- synthesis was inhibited by L-NMMA and IL-4. It was increased with HOArg under conditions of NO inhibition. In contrast, in normal glomeruli and basal MC, where there was no induced NO synthesis, IL-4 had no effect on arginase activity, whereas HOArg consistently reduced it in glomeruli only. Type II arginase (Arg II) mRNA was detected in normal glomeruli; nephritic glomeruli expressed both Arg I and Arg II mRNAs. This is the first demonstration of arginase modulation in glomeruli and MC and of the expression of arginase isoforms in glomeruli. The differential responses to two endogenous compounds generated by inflammation suggest this may be part of coordinated regulation of arginase and inducible NOS in immune injury, whereby arginase is inhibited during high-output NO production and stimulated with NO suppression. This, together with control of arginase and NOS isoforms, may be important in controlling the balance of inflammatory and repair mechanisms.


Assuntos
Arginase/metabolismo , Arginina/análogos & derivados , Mesângio Glomerular/enzimologia , Interleucina-4/fisiologia , Isoenzimas/metabolismo , Glomérulos Renais/enzimologia , Nefrite/enzimologia , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Arginina/metabolismo , Arginina/farmacologia , Toxina da Cólera/farmacologia , AMP Cíclico/fisiologia , Interleucina-1/farmacologia , Interleucina-4/farmacologia , Macrófagos Peritoneais/metabolismo , Masculino , Nitritos/metabolismo , Ratos , Ratos Endogâmicos Lew
16.
Kidney Int ; 53(4): 932-6, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9551400

RESUMO

Nitric oxide is synthesized in experimental immune complex glomerulonephritis due to local induction of type 2 nitric oxide synthase (NOS2). To determine the role of NOS2, the course of accelerated anti-glomerular basement membrane glomerulonephritis (anti-GBM) was examined in mice homozygous for disruption of the NOS2 gene compared with heterozygous littermates. Disease in the wild type strain (129Sv) was characterized by heavy albuminuria, glomerular neutrophil and macrophage infiltration and glomerular thrombosis. NOS2, interleukin 1B (IL-1 beta) and tumor necrosis factor alpha (TNF alpha) mRNA were induced by 24 hours. The NOS2-deficient mutant mice and the heterozygous mice displayed early (24 hr) and full autologous phase (day 6) injury indistinguishable from the wild-type mice. The equivalent degree of albuminuria and glomerular inflammation indicates that NOS2 does not play an essential role in this form of glomerulonephritis in the mouse.


Assuntos
Doença Antimembrana Basal Glomerular/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Camundongos Knockout/fisiologia , Óxido Nítrico Sintase/genética , Animais , Doença Antimembrana Basal Glomerular/imunologia , Anticorpos/farmacologia , Autoanticorpos , Membrana Basal/enzimologia , Membrana Basal/imunologia , Heterozigoto , Homozigoto , Camundongos , RNA Mensageiro/análise
17.
Kidney Int ; 53(3): 672-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9507213

RESUMO

Heme oxygenase (HO) catalyses degradation of heme to biliverdin, iron and carbon monoxide (CO). Two isoforms exist, a constitutive form and an inducible form (HO-1). Induction of HO-1 may have protective effects in inflammation. We studied heterologous (HNTN) and accelerated (ANTN) nephrotoxic nephritis in Lewis rats. Hemin, an inducer of HO-1, (30 mumol/kg) was administered 18 hours before induction of nephritis and 72 hours later in ANTN. HO-1 was not detected immunohistochemically in normal glomeruli but was present in HNTN and ANTN in cells with the morphology of macrophages. HO-1 induction was confirmed by RT-PCR. In normal rats hemin induced glomerular HO-1 mRNA at 18 hours. In HNTN hemin markedly reduced proteinuria at 24 hours (10 +/- 4 mg/24 hr; control 54 +/- 16; P < 0.05), neutrophil infiltration at two hours (29.8 +/- 1.8 vs. 22.3 +/- 1.5 neutrophils/glomerulus, P < 0.05), and glomerular macrophage number at two hours (2.1 +/- 0.1 vs. 3.1 +/- 0.4 cells/glomerulus, P < 0.05). In ANTN proteinuria was reduced at day 1 and day 4 (36 +/- 11 vs. 60 +/- 15 and 36 +/- 7 vs. 86 +/- 9 mg protein/24 hr, respectively, P < 0.001), glomerular thrombi were reduced by hemin at day 1 and 4 (1.5 +/- 2.7 vs. 2.7 +/- 0.2 and 1.3 +/- 0.01 vs. 2.9 +/- 0.02, respectively, P < 0.001) and glomerular macrophage infiltration was reduced on day 4 (11.2 +/- 0.8 cells/glom; control 15.9 +/- 0.8, P < 0.01). Possible mechanisms by which HO-1 ameliorates disease include anti-complement or anti-oxidant effects of bilirubin and vasodilator and anti-platelet effects of carbon monoxide.


Assuntos
Glomerulonefrite/enzimologia , Glomerulonefrite/prevenção & controle , Heme Oxigenase (Desciclizante)/biossíntese , Hemina/farmacologia , Animais , Indução Enzimática/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glomerulonefrite/etiologia , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1 , Imuno-Histoquímica , Rim/enzimologia , Rim/patologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew , Fatores de Tempo
19.
J Exp Med ; 186(9): 1451-9, 1997 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-9348302

RESUMO

Systemic lupus erythematosus (SLE) is a potentially fatal non-organ-specific autoimmune disease that predominantly affects women. Features of the disease include inflammatory skin lesions and widespread organ damage caused by deposition of anti-dsDNA autoantibodies. The mechanism and site of production of these autoantibodies is unknown, but there is evidence that interferon (IFN) gamma plays a key role. We have used the involucrin promoter to overexpress IFN-gamma in the suprabasal layers of transgenic mouse epidermis. There was no evidence of organ-specific autoimmunity, but transgenic animals produced autoantibodies against dsDNA and histones. Autoantibody levels in female mice were significantly higher than in male transgenic mice. Furthermore, there was IgG deposition in the glomeruli of all female mice and histological evidence of severe proliferative glomerulonephritis in a proportion of these animals. Our findings are consistent with a central role for the skin immune system, acting under the influence of IFN-gamma, in the pathogenesis of SLE.


Assuntos
Anticorpos Antinucleares/genética , Epiderme/metabolismo , Interferon gama/biossíntese , Nefrite Lúpica/genética , Nefrite Lúpica/imunologia , Animais , Anticorpos Antinucleares/biossíntese , Anticorpos Antinucleares/sangue , Especificidade de Anticorpos/genética , Complexo Antígeno-Anticorpo/metabolismo , DNA/imunologia , Feminino , Glomerulonefrite/genética , Glomerulonefrite/imunologia , Histonas/imunologia , Interferon gama/genética , Nefrite Lúpica/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos MRL lpr , Camundongos Transgênicos , Especificidade de Órgãos/imunologia
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