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BACKGROUND: Therapeutic plasma exchange (TPE) is utilised in the management of a limited number of paediatric renal conditions. Despite its widespread acceptance and advancements in the practice of apheresis, there remains a paucity of data pertaining to paediatrics. We present a large retrospective review of our cohort of paediatric patients undergoing TPE for renal indications, outlining their outcomes and complications. METHODS: A retrospective chart review was conducted for all patients (under 16 years) undergoing TPE for renal conditions between January 2002 and June 2019 in Ireland. Demographic and clinical data were extracted, with patients anonymised and stratified according to their pathology. RESULTS: A total of 58 patients were identified. A total of 1137 exchanges were performed using heparin sodium anticoagulation. The median age was 35.5 months (IQR 18-110 months). The leading indication was neurological involvement in Shiga toxin-producing Escherichia coli haemolytic uraemic syndrome (STEC-HUS) (n = 29). Complications (minor or major) occurred in 65.5% (n = 38) of patients, with most experiencing minor complications 58.6% (n = 34). Asymptomatic hypocalcaemia was the most common complication in 43.1% (n = 25). CONCLUSIONS: Our experience of TPE, spanning 1137 exchanges, proved a safe, well-tolerated therapy. Most complications were minor, and with therapy conducted in specialised centres, there are very low levels of adverse events.
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BACKGROUND: Adolescence is a time of significant change for patients, guardians and clinicians. The paediatrician must ensure patients develop the necessary skills and knowledge required to transition and to function as an independent entity, with autonomy over their own care. The transfer from paediatric to adult care carries an increased risk of graft-related complications attributable to a multitude of reasons, particularly non-adherence to immunosuppressive medicines and poor attendance at scheduled appointments. This systematic review was conducted to ascertain the transitional care models available to clinicians caring for kidney transplant recipients and to compare the approach in each respective case. METHODS: A systematic review was performed, in a methodology outlined by the PRISMA guidelines. OVID MEDLINE and EMBASE databases were searched for studies that outlined valid, replicable models pertaining to transitional care of paediatric kidney transplant recipients between 1946 and Quarter 3 of 2021. The reference lists of selected articles were also perused for further eligible studies and experts in the field were consulted for further eligible articles. Two investigators assessed all studies for eligibility and independently performed data extraction. Any discrepancies were settled by consensus. RESULTS: A total of 1121 abstracts were identified, which was reduced to 1029 upon removal of duplicates. A total of 51 articles were deemed appropriate for full-text review and critical appraisal. A total of 12 articles that described models for transition pertaining to kidney transplant patients were included in qualitative synthesis. Every paper utilized a different transition model. All but one model included a physician and nurse at minimum in the transition process. The involvement of adult nephrologists, medical social work, psychology and psychiatry was variable. The mean age for the initiation of transition was 13.4 years (range: 10-17.5 years). The mean age at transfer to adult services was 18.3 years (range: 16-20.5 years). CONCLUSIONS: Despite the well-established need for good transitional care for paediatric solid-organ transplant recipients, models tailored specifically for kidney transplant recipients are lacking. Further research and validation studies are required to ascertain the best method of providing effective transitional care to these patients. Transitional care should become a standardized process for adolescents and young adults with kidney transplants.
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Transplante de Rim , Transição para Assistência do Adulto , Cuidado Transicional , Adulto Jovem , Humanos , Criança , Adolescente , Adulto , Transplante de Rim/efeitos adversosRESUMO
Acute kidney injury (AKI) is a common problem in the neonatal intensive care unit (NICU). Neonates born at <1,000 g (extremely low birth weight, ELBW) are at an increased risk of secondary associated comorbidities such as intrauterine growth restriction, prematurity, volume restriction, ischaemic injury, among others. Studies estimate up to 50% ELBW infants experience at least one episode of AKI during their NICU stay. Although no curative treatment for AKI currently exists, recognition is vital to reduce potential ongoing injury and mitigate long-term consequences of AKI. However, the definition of AKI is imperfect in this population and presents clinical challenges to correct identification, thus contributing to under recognition and reporting. Additionally, the absence of guidelines for the management of AKI in ELBW infants has led to variations in practice. This review summarizes AKI in the ELBW infant and includes suggestions such as close observation of daily fluid balance, review of medications to reduce nephrotoxic exposure, management of electrolytes, maximizing nutrition, and the use of diuretics and/or dialysis when appropriate.
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Our objective was to establish the rate of neurological involvement in Shiga toxin-producing Escherichia coli-hemolytic uremic syndrome (STEC-HUS) and describe the clinical presentation, management and outcome. A retrospective chart review of children aged ≤ 16 years with STEC-HUS in Children's Health Ireland from 2005 to 2018 was conducted. Laboratory confirmation of STEC infection was required for inclusion. Neurological involvement was defined as encephalopathy, focal neurological deficit, and/or seizure activity. Data on clinical presentation, management, and outcome were collected. We identified 240 children with HUS; 202 had confirmed STEC infection. Neurological involvement occurred in 22 (11%). The most common presentation was seizures (73%). In the neurological group, 19 (86%) were treated with plasma exchange and/or eculizumab. Of the 21 surviving children with neurological involvement, 19 (91%) achieved a complete neurological recovery. A higher proportion of children in the neurological group had renal sequelae (27% vs. 12%, P = .031). One patient died from multi-organ failure.Conclusion: We have identified the rate of neurological involvement in a large cohort of children with STEC-HUS as 11%. Neurological involvement in STEC-HUS is associated with good long-term outcome (complete neurological recovery in 91%) and a low case-fatality rate (4.5%) in our cohort. What is Known: ⢠HUS is associated with neurological involvement in up to 30% of cases. ⢠Neurological involvement has been reported as predictor of poor outcome, with associated increased morbidity and mortality. What is New: ⢠The incidence of neurological involvement in STEC-HUS is 11%. ⢠Neurological involvement is associated with predominantly good long-term outcome (90%) and a reduced case-fatality rate (4.5%) compared to older reports.
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Infecções por Escherichia coli , Síndrome Hemolítico-Urêmica , Escherichia coli Shiga Toxigênica , Adolescente , Criança , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/terapia , Síndrome Hemolítico-Urêmica/complicações , Síndrome Hemolítico-Urêmica/diagnóstico , Síndrome Hemolítico-Urêmica/epidemiologia , Humanos , Troca Plasmática , Estudos RetrospectivosRESUMO
Cerebral Palsy (CP) describes a heterogenous group of non-progressive disorders of posture or movement, causing activity limitation, due to a lesion in the developing brain. CP is an umbrella term for a heterogenous condition and is, therefore, descriptive rather than a diagnosis. Each case requires detailed consideration of etiology. Our understanding of the underlying cause of CP has developed significantly, with areas such as inflammation, epigenetics and genetic susceptibility to subsequent insults providing new insights. Alongside this, there has been increasing recognition of the multi-organ dysfunction (MOD) associated with CP, in particular in children with higher levels of motor impairment. Therefore, CP should not be seen as an unchanging disorder caused by a solitary insult but rather, as a condition which evolves over time. Assessment of multi-organ function may help to prevent complications in later childhood or adulthood. It may also contribute to an improved understanding of the etiology and thus may have an implication in prevention, interventional methods and therapies. MOD in CP has not yet been quantified and a scoring system may prove useful in allowing advanced clinical planning and follow-up of children with CP. Additionally, several biomarkers hold promise in assisting with long-term monitoring. Clinicians should be aware of the multi-system complications that are associated with CP and which may present significant diagnostic challenges given that many children with CP communicate non-verbally. A step-wise, logical, multi-system approach is required to ensure that the best care is provided to these children. This review summarizes multi-organ dysfunction in children with CP whilst highlighting emerging research and gaps in our knowledge. We identify some potential organ-specific biomarkers which may prove useful in developing guidelines for follow-up and management of these children throughout their lifespan.
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BACKGROUND: CAKUT are the most common cause of end-stage renal failure in children (Pediatr Nephrol. 24, 2009, 1719). Many children with CAKUT have poor urinary drainage which can compromise post-transplant outcome. Identifying safe ways to manage anatomical abnormalities and provide effective urinary drainage is key to transplant success. Much debate exists regarding optimum urinary diversion techniques. The definitive formation of a continent urinary diversion is always preferable but may not always be possible. We explore the role of ureterostomy formation at transplantation in a complex pediatric group. METHODS: We report six pediatric patients who had ureterostomy formation at the time of transplantation at the National Paediatric Transplant Centre in Dublin, Ireland. We compared renal function and burden of urinary tract infection to a group with alternative urinary diversion procedures and a group with normal bladders over a 5-year period. RESULTS: There was no demonstrable difference in estimated glomerular filtration rate between the groups at 5-year follow-up. The overall burden of UTI was low and similar in frequency between the three groups. CONCLUSIONS: Ureterostomy formation is a safe and effective option for temporary urinary diversion in children with complex abdominal anatomy facilitating transplantation; it is, however, important to consider the implications and risk of ureterostomy for definitive surgery after transplantation.
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Transplante de Rim/métodos , Ureterostomia , Anormalidades Urogenitais/cirurgia , Refluxo Vesicoureteral/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Derivação UrináriaRESUMO
The T cell-specific adaptor protein (TSAd), encoded by the SH2D2A gene, is an intracellular molecule that binds Lck to elicit signals that result in cytokine production in CD4+ T effector cells (Teff). Nevertheless, using Sh2d2a knockout (KO; also called TSAd-/-) mice, we find that alloimmune CD4+ Teff responses are fully competent in vivo. Furthermore, and contrary to expectations, we find that allograft rejection is accelerated in KO recipients of MHC class II-mismatched B6.C-H-2bm12 heart transplants versus wild-type (WT) recipients. Also, KO recipients of fully MHC-mismatched cardiac allografts are resistant to the graft-prolonging effects of costimulatory blockade. Using adoptive transfer models, we find that KO T regulatory cells (Tregs) are less efficient in suppressing Teff function and they produce IFN-γ following mitogenic activation. In addition, pyrosequencing demonstrated higher levels of methylation of CpG regions within the Treg-specific demethylated region of KO versus WT Tregs, suggesting that TSAd, in part, promotes Treg stability. By Western blot, Lck is absent in the mitochondria of KO Tregs, and reactive oxygen species production by mitochondria is reduced in KO versus WT Tregs. Full transcriptomic analysis demonstrated that the key mechanism of TSAd function in Tregs relates to its effects on cellular activation rather than intrinsic effects on mitochondria/metabolism. Nevertheless, KO Tregs compensate for a lack of activation by increasing the number of mitochondria per cell. Thus, TSAd serves as a critical cell-intrinsic molecule in CD4+Foxp3+ Tregs to regulate the translocation of Lck to mitochondria, cellular activation responses, and the development of immunoregulation following solid organ transplantation.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T CD4-Positivos/imunologia , Mitocôndrias/metabolismo , Transplante , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/citologia , Proliferação de Células , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
BACKGROUND: Cardiac allograft vasculopathy (CAV) is the leading cause of chronic allograft loss after pediatric heart transplantation. We hypothesized that biomarkers of endothelial injury and repair would predict CAV development in pediatric heart transplant recipients. METHODS: Blood was collected from pediatric heart transplant recipients at the time of routine annual coronary angiography, and the concentrations of 13 angiogenesis-related molecules were determined. The primary end point was the presence of moderate or severe CAV by angiography during a 5-year follow-up period. RESULTS: The study enrolled 48 recipients (57% male) with a median age of 15.5 years (range, 2-22 years) and median time post-transplant of 5.8 years (range, 2-15 years). Eight recipients developed moderate/severe CAV at a median follow-up of 4.7 years, of whom 3 died, 3 underwent retransplantation, 1 had a myocardial infarction, and 1 was listed for retransplantation. Clinical characteristics associated with the development of moderate/severe CAV included prednisone use at enrollment (p = 0.03) and positive recipient cytomegalovirus immunoglobulin G at the time of transplant (p = < 0.01). Multivariable Cox proportional hazards regression identified plasma vascular endothelial growth factor (VEGF)-A concentration greater than 90 pg/ml at the time of blood draw as a significant predictor of time to moderate or severe CAV (hazard ratio, 14.3; 95% confidence interval, 1.3-163). Receiver operating characteristic curve analysis demonstrated that VEGF-A shows moderate performance for association with the subsequent development of CAV (area under the curve, 0.77; 95% confidence interval, 0.61-0.92). CONCLUSIONS: VEGF-A levels in pediatric heart transplant recipients are associated with clinically important CAV progression within the subsequent 5 years.
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Aloenxertos , Doença das Coronárias/sangue , Insuficiência Cardíaca/sangue , Transplante de Coração/efeitos adversos , Complicações Pós-Operatórias/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Doença das Coronárias/diagnóstico , Doença das Coronárias/etiologia , Feminino , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Adulto JovemRESUMO
BACKGROUND: Dent disease 1 is a rare cause of chronic kidney disease (CKD) in childhood secondary to mutations in the gene encoding the chloride-proton exchanger, CLC-5, which is found mainly in the proximal tubule. Clinical manifestations are variable and there are no known genotype-phenotype correlations. CASE DIAGNOSIS/TREATMENT: The proband was identified as having a mutation in CLCN5. The extended family of the proband was invited to participate in a study of Dent disease after several males were noted to have a history of CKD. Urine retinol binding protein, urine calcium, serum creatinine, and DNA samples were collected for analysis. Ten hemizygous males and 6 heterozygous females were identified. Advanced CKD was detected in 3 males (1 child). Renal biopsies in 4 children showed both glomerular and tubulo-interstitial changes. There was no correlation between age and disease severity. CONCLUSIONS: This is the first reported family from the southern hemisphere with this condition. A novel CLCN5 mutation is described, c.1618G>C (p.Ala540Pro). The severity of renal disease varies greatly among individuals.
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Canais de Cloreto/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Nefrolitíase/genética , Fenótipo , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Humanos , Hipercalciúria/urina , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/etiologia , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Nefrolitíase/diagnóstico , Nefrolitíase/fisiopatologia , Nova Zelândia , Proteinúria/urina , Insuficiência Renal Crônica/etiologia , UltrassonografiaRESUMO
Cellular heterogeneity presents an important challenge to the development of cell-based therapies where there is a fundamental requirement for predictable and reproducible outcomes. Transplanted Dental Pulp Stem/Progenitor Cells (DPSCs) have demonstrated early promise in experimental models of spinal cord injury and stroke, despite limited evidence of neuronal and glial-like differentiation after transplantation. Here, we report, for the first time, on the ability of single cell-derived clonal cultures of murine DPSCs to differentiate in vitro into immature neuronal-like and oligodendrocyte-like cells. Importantly, only DPSC clones with high nestin mRNA expression levels were found to successfully differentiate into Map2 and NF-positive neuronal-like cells. Neuronally differentiated DPSCs possessed a membrane capacitance comparable with primary cultured striatal neurons and small inward voltage-activated K(+) but not outward Na(+) currents were recorded suggesting a functionally immature phenotype. Similarly, only high nestin-expressing clones demonstrated the ability to adopt Olig1, Olig2, and MBP-positive immature oligodendrocyte-like phenotype. Together, these results demonstrate that appropriate markers may be used to provide an early indication of the suitability of a cell population for purposes where differentiation into a specific lineage may be beneficial and highlight that further understanding of heterogeneity within mixed cellular populations is required.
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BACKGROUND: Acute pediatric dialysis is provided by a single center in New Zealand. Most acute dialysis in our center is performed in the under 5 age group. The advantage of using peritoneal dialysis (PD) in these children is the ability to perform continuous renal replacement therapy without always requiring an ICU setting, avoiding central venous access and promoting greater cardiovascular stability. The disadvantage of PD in the acute setting includes the requirement for immediate use and the potential for early leaks due to peritoneal disruption with resulting delayed use and restricted volumes. There is a growing trend toward minimally invasive surgery and the laparoscopic method allows this. Surgeons at this center have been using a laparoscopic technique since 2005. METHODS: We performed a 10-year review of acute PD at the Starship Hospital from 2003 to 2013. Data on 102 children who met the criteria were collected. RESULTS: These 102 children had 113 acute PD catheters. The two groups were comparable in terms of age and reason for presentation. The median age of the laparoscopic group was 2 years (interquartile range [IQR] 6) and the open group was 3 years (IQR 3.2). The predominant diagnosis for both groups was hemolytic uremic syndrome (HUS) accounting for 71% of laparoscopic cases, and 72% of open cases. The incidence of infection was 0% versus 7% in the laparoscopic versus open approach. Ten percent of patients required further manipulation of the catheter after initial insertion in the laparoscopic group, compared with 11% in the open approach. Conversion to hemodialysis (HD) due to catheter-related complications was seen in 10% of laparoscopic cases and 9% of the open cases. Dialysate fluid leak was noted in 26% in the laparoscopic group compared with 11% in the open group (p = 0.08). Anesthesia time is longer in the laparoscopic group (p = 0.008). CONCLUSION: We found no significant differences in complication rates between laparoscopic and open surgical approaches regarding acute PD catheter insertion. We saw a trend in increased leakage with laparoscopic procedures and a significantly longer operative time. We concluded that the laparoscopic approach in the acute situation for emergency dialysis is safe and effective.
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Injúria Renal Aguda/terapia , Cateteres de Demora , Laparoscopia/métodos , Diálise Peritoneal/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Laparoscopia/efeitos adversos , Masculino , Nova Zelândia , Diálise Peritoneal/efeitos adversos , Complicações Pós-Operatórias , Estudos RetrospectivosRESUMO
UNLABELLED: Phaeochromocytomas are a rare clinical entity, with dual hormone-secreting lesions particularly uncommon, seen in <1%. ACTH is the most common hormone co-produced, and is potentially lethal if not diagnosed. We present the case of a previously well 10-year-old boy, who presented acutely with a hypertensive crisis and was found to have a unilateral, non-syndromic phaeochromocytoma. Medical stabilization of his hypertension was challenging, and took 3 weeks to achieve, before proceeding to unilateral adrenalectomy. Post-operatively the child experienced severe fatigue and was subsequently confirmed to have adrenal insufficiency. He improved markedly with hydrocortisone replacement therapy, which is ongoing 6 months post-operatively. In retrospect this likely represents unrecognized, sub-clinical ACTH-dependent Cushing's syndrome secondary to an ACTH/or precursor dual-hormone secreting phaeochromocytoma. At follow-up, his hypertension had resolved, there was no biochemical evidence of recurrence of the phaeochromocytoma, and genetic analysis was indicative of a sporadic lesion. LEARNING POINTS: Dual hormone secreting phaeochromocytomas with ACTH/or a precursor may cause secondary adrenal insufficiency following surgical removal.The concurrent features of Cushing's syndrome can be mild and easily overlooked presenting diagnostic and management pitfalls.As concomitant syndromes of hormone excess are rare in phaeochromocytomas; the diagnosis requires a high index of suspicion.Serial/diurnal cortisol levels, ACTH measurement +/- low dose dexamethasone suppression (when clinically stable, appropriate adrenergic blockade in place, and well supervised), can all be considered as needed.
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The childhood obesity epidemic continues to be a serious concern in the U.S., disproportionately affecting low socioeconomic and minority groups. Because many interventions are based in schools, both individual and school factors contributing to obesity were examined in this study. Employing data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K), a three level hierarchical linear model was used to estimate children's body mass index (BMI) growth trajectories within their school contexts. Results indicated an inverse relationship between BMI and socioeconomic status (SES), except for black males. Additionally, results showed that low school SES and rural locality of the school were school-level risk factors of obesity. Lastly, a major portion of the between-schools variance was explained by aggregated student characteristics, indicating that students were more likely to attend schools with peers of similar BMI who had similar SES and race/ethnicity, supporting a school-level compositional effect associated with obesity.
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Desenvolvimento Infantil , Obesidade Infantil/epidemiologia , Instituições Acadêmicas , Índice de Massa Corporal , Criança , Demografia , Feminino , Humanos , Modelos Lineares , Masculino , Análise Multinível , Obesidade Infantil/etnologia , Fatores de Risco , Fatores Socioeconômicos , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Early institution of enteral feeding in paediatric end-stage kidney disease (ESKD) is recommended. For patients on peritoneal dialysis (PD) there is concern that gastrostomy tube (GT) insertion may be complicated by increased peritonitis, in particular fungal. Our unit favours early planned GT insertion, and for those with late presentation, there is prompt consideration of GT insertion following dialysis initiation. This study evaluates our rates of peritonitis with GT insertion following or concurrent with PD initiation. METHODS: This was a retrospective, single-centre, cross-sectional study of of 17 New Zealand children with ESKD who received PD in the period 2000-2011. Inclusion criteria were GT placement while on PD or initiation of PD within 72 h of GT insertion. RESULTS: There were no cases of fungal peritonitis among the 17 children; however, two cases of early peritonitis with organisms derived from the gastrointestinal tract were identified. No statistically significant difference was found between incident rates of bacterial peritonitis before GT placement (0.6 episodes per patient-year; 95% confidence interval (CI) 0.26-1.18) and post-GT placement (1.21 episodes per patient-year; 95% CI 0.69-1.97). CONCLUSION: Fungal peritonitis has never been encountered by out unit during its many years of experience in GT placement in patients without advanced malnutrition. When children on PD have insufficient dietary intake to maintain appropriate growth velocity, enteral feeding should be initiated promptly. A GT is considered to be safe for long-term use in selected patients.
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Gastrostomia/efeitos adversos , Diálise Peritoneal , Peritonite/epidemiologia , Peritonite/etiologia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Nutrição Enteral/efeitos adversos , Nutrição Enteral/métodos , Feminino , Humanos , Lactente , Recém-Nascido , Falência Renal Crônica/terapia , Masculino , Estudos RetrospectivosRESUMO
In these studies, we find that the vascular endothelial growth factor (VEGF) receptor KDR is expressed on subsets of mitogen-activated CD4(+) and CD8(+) T cells in vitro. We also found that KDR colocalizes with CD3 on mitogen-activated T cells in vitro and on infiltrates within rejecting human allografts in vivo. To evaluate whether VEGF and KDR mediate lymphocyte migration across endothelial cells (ECs), we used an in vitro live-time transmigration model and observed that both anti-VEGF and anti-KDR antibodies inhibit the transmigration of both CD4(+) and CD8(+) T cells across tumor necrosis factor α (TNFα)-activated, but not unactivated ECs. In addition, we found that interactions among CD4(+) or CD8(+) T cells and TNFα-activated ECs result in the induction of KDR on each T cell subset, and that KDR-expressing lymphocytes preferentially transmigrate across TNFα-activated ECs. Finally, using a humanized severe combined immunodeficient mouse model of lymphocyte trafficking, we found that KDR-expressing lymphocytes migrate into human skin in vivo, and that migration is reduced in mice treated with a blocking anti-VEGF antibody. These observations demonstrate that induced expression of KDR on subsets of T cells, and locally expressed VEGF, facilitate EC-dependent lymphocyte chemotaxis, and thus, the localization of T cells at sites of inflammation.
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Movimento Celular/fisiologia , Linfócitos T/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Anticorpos/imunologia , Anticorpos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Western Blotting , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Citometria de Fluxo , Prepúcio do Pênis/metabolismo , Prepúcio do Pênis/transplante , Humanos , Recém-Nascido , Masculino , Camundongos , Camundongos SCID , Microscopia de Fluorescência , Interferência de RNA , Transplante de Pele , Linfócitos T/citologia , Transplante Heterólogo , Fator de Necrose Tumoral alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologiaRESUMO
In this study, we find that CD45RO+ memory populations of CD4+ T lymphocytes express the vascular endothelial growth factor (VEGF) receptors KDR and Flt-1 at both the mRNA and protein levels. Furthermore, by Western blot analysis, we find that VEGF increases the phosphorylation and activation of ERK and Akt within CD4+CD45RO+ T cells. These VEGF-mediated signaling responses were inhibited by a KDR-specific small interfering RNA in a VEGF receptor-expressing Jurkat T cell line and by SU5416, a pharmacological KDR inhibitor, in CD4+CD45RO+ T cells. We also find that VEGF augments mitogen-induced production of IFN-gamma in a dose-dependent manner (p < 0.001) and significantly (p < 0.05) increases directed chemotaxis of this T cell subset. Collectively, our results for the first time define a novel function for VEGF and KDR in CD45RO+ memory T cell responses that are likely of great pathophysiological importance in immunity.
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Linfócitos T CD4-Positivos/imunologia , Memória Imunológica , Interferon gama/biossíntese , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , Células Cultivadas , Quimiotaxia , Humanos , Células Jurkat , Antígenos Comuns de Leucócito , RNA Mensageiro/análise , Transdução de Sinais/imunologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/fisiologiaRESUMO
OBJECTIVE: To compare neurally adjusted ventilatory assist ventilation with pressure-support ventilation. DESIGN: Prospective, crossover comparison study. SETTING: Tertiary care pediatric and neonatal intensive care unit. PATIENTS: Sixteen ventilated infants and children: mean age = 9.7 months (range = 2 days-4 yrs) and mean weight = 6.2 kg (range = 2.4-13.7kg). INTERVENTIONS: A modified nasogastric tube was inserted and correct positioning was confirmed. Patients were ventilated in pressure-support mode with a pneumatic trigger for a 30-min period and then in neurally adjusted ventilatory assist mode for up to 4 hrs. MEASUREMENTS AND MAIN RESULTS: Data collected for comparison included activating trigger (neural vs. pneumatic), peak and mean airway pressures, expired minute and tidal volumes, heart rate, respiratory rate, pulse oximetry, end-tidal CO2 and arterial blood gases. Synchrony was improved in neurally adjusted ventilatory assist mode with 65% (+/-21%) of breaths triggered neurally vs. 35% pneumatically (p < .001) and 85% (+/-8%) of breaths cycled-off neurally vs. 15% pneumatically (p = .0001). The peak airway pressure in neurally adjusted ventilatory assist mode was significantly lower than in pressure-support mode with a 28% decrease in pressure after 30 mins (p = .003) and 32% decrease after 3 hrs (p < .001). Mean airway pressure was reduced by 11% at 30 mins (p = .13) and 9% at 3 hrs (p = .31) in neurally adjusted ventilatory assist mode although this did not reach statistical significance. Patient hemodynamics and gas exchange remained stable for the study period. No adverse patient events or device effects were noted. CONCLUSIONS: In a neonatal and pediatric intensive care unit population, ventilation in neurally adjusted ventilatory assist mode was associated with improved patient-ventilator synchrony and lower peak airway pressure when compared with pressure-support ventilation with a pneumatic trigger. Ventilating patients in this new mode seem to be safe and well tolerated.
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Unidades de Terapia Intensiva Neonatal , Unidades de Terapia Intensiva Pediátrica , Respiração com Pressão Positiva/métodos , Estudos Cross-Over , Diafragma/inervação , Diafragma/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Irlanda , Masculino , Estudos Prospectivos , Resultado do TratamentoRESUMO
OBJECTIVE: Before the advent of antituberculous chemotherapy, thoracoplasty (TPL) was the definitive form of therapy for cavitary pulmonary tuberculosis. This study aimed to characterize the late functional sequelae of TPL, and to establish the degree of reversibility of any consequent airway obstruction. METHODOLOGY: Pulmonary function was studied in 21 long-term (mean 35 years) survivors of TPL between the years 1990-2001. RESULTS: A mixed obstructive/restrictive defect was found in this patient cohort. After inhalation of bronchodilator, marginal increases in FEV(1) and FVC and marginal decreases in FRC, RV and TLC were observed. Maximum mid-expiratory flow rate was severely reduced (28.8% of predicted), but reversibility after inhaled beta(2)-agonist was highest for this parameter of pulmonary function (mean 11%). Smokers had a higher RV (P = 0.04), suggesting hyperinflation, while non-smokers had a larger increase in FEV(1)/FVC ratio postbronchodilator (P = 0.004), suggesting more marked reversibility of airways obstruction in this group. CONCLUSIONS: Long-term survivors of TPL have an obstructive as well as a restrictive ventilatory defect. These patients have partial reversibility of the obstructive defect. The degree of reversibility found suggests that bronchodilator therapy may help these patients.