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1.
Mo Med ; 114(2): 125-128, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30228559

RESUMEN

This review seeks to educate clinicians and advocate for patients having acute-onset pediatric autoimmune encephalopathy. Primary care providers caring for children are not fully aware of the debilitating illness that changes the life of a child and a family overnight. Our goal is to heighten awareness of a) the initial diagnosis, b) treatment and c) information about referral of affected children by health professionals in Missouri and surrounding states.

2.
J Pediatr ; 175: 68-73.e3, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27260839

RESUMEN

OBJECTIVE: To evaluate the safety and explore the efficacy of recombinant human lactoferrin (talactoferrin [TLf]) to reduce infection. STUDY DESIGN: We conducted a randomized, double blind, placebo-controlled trial in infants with birth weight of 750-1500 g. Infants received enteral TLf (n = 60) or placebo (n = 60) on days 1 through 28 of life; the TLf dose was 150 mg/kg every 12 hours. Primary outcomes were bacteremia, pneumonia, urinary tract infection, meningitis, and necrotizing enterocolitis (NEC). Secondary outcomes were sepsis syndrome and suspected NEC. We recorded clinical, laboratory, and radiologic findings, along with diseases and adverse events, in a database used for statistical analyses. RESULTS: Demographic data were similar in the 2 groups of infants. We attributed no enteral or organ-specific adverse events to TLf. There were 2 deaths in the TLf group (1 each due to posterior fossa hemorrhage and postdischarge sudden infant death), and 1 death in the placebo group, due to NEC. The rate of hospital-acquired infections was 50% lower in the TLf group compared with the placebo group (P < .04), including fewer blood or line infections, urinary tract infections, and pneumonia. Fourteen infants in the TLf group weighing <1 kg at birth had no gram-negative infections, compared with only 3 of 14 such infants in the placebo group. Noninfectious outcomes were not statistically significantly different between the 2 groups, and there were no between-group differences in growth or neurodevelopment over a 1-year posthospitalization period. CONCLUSION: We found no clinical or laboratory toxicity and a trend toward less infectious morbidity in the infants treated with TLf. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00854633.


Asunto(s)
Infección Hospitalaria/prevención & control , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Grampositivas/prevención & control , Enfermedades del Prematuro/prevención & control , Lactoferrina/uso terapéutico , Sustancias Protectoras/uso terapéutico , Administración Oral , Bacteriemia/prevención & control , Método Doble Ciego , Enterocolitis Necrotizante/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Meningitis/prevención & control , Neumonía/prevención & control , Sepsis/prevención & control , Resultado del Tratamiento , Infecciones Urinarias/prevención & control
3.
J Pediatr ; 173 Suppl: S37-42, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27234409

RESUMEN

UNLABELLED: The purpose of this study is to evaluate the effects of enteral lactoferrin on the fecal microbiome and contrast those influences with the neonatal intensive care unit (NICU) environment. We theorized that lactoferrin and the NICU habitat shape the fecal microbial composition of very preterm infants. Although functions attributed to lactoferrin include intestinal immune system development and emergence of a healthy gut microbiota, evidence is limited. Twenty-one very low birth weight (VLBW <1500 g) infants received twice-daily talactoferrin (TLf, a drug designation for recombinant human lactoferrin) or its excipient by gastric gavage from day 1-28 of life. Twenty-four-hour fecal samples were collected on day 21 of life and compared with fecal operational taxonomy units (OTUs) in treated and control infants in 2 NICUs. Workflow included fecal DNA isolation, generation of amplicons for the V1-V3 region of bacterial 16S ribosomal RNA, and sequencing of a gel-purified multiplex amplicon library using a Roche 454 GS FLX Titanium (Roche, Branford, Connecticut) platform and protocols. Fecal OTUs per infant were higher in NICU 1 vs NICU 2 (P < .001), consistent with fewer antibiotic days (P < .02) and a shorter duration of parenteral nutrition (P < .007) in NICU 1. Proteobacteria and Firmicutes were the major phyla in infants treated with TLf and placebo. Among Enterobacteriaceae, TLf prophylaxis reduced Enterobacter and Klebsiella, but increased Citrobacter in feces of VLBW infants. Citrobacter caused no neonatal infections in the study population. OTUs for Clostridiaceae increased in NICU 1 among infants treated with TLf. Importantly, OTUs of staphylococci were barely detectable in both NICUs among infants fed TLf. Fewer hospital-acquired infections occurred in infants treated with TLf vs controls, although the reduction was seen mostly in coagulase-negative staphylococci-related bloodstream and central line infections (P = .06). TLf modified the fecal microbiome in VLBW infants, but care practices in the NICU habitat also contributed. Future research must establish whether elimination vs enrichment of gut-related microbiota reduces clinically significant hospital-acquired infections and promotes a healthy commensal microflora in the intestines of VLBW infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00854633.


Asunto(s)
Antiinfecciosos/farmacología , Heces/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Cuidado Intensivo Neonatal/métodos , Lactoferrina/farmacología , Administración Oral , Antiinfecciosos/uso terapéutico , Infección Hospitalaria/prevención & control , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Enfermedades del Prematuro/prevención & control , Unidades de Cuidado Intensivo Neonatal , Lactoferrina/uso terapéutico , Masculino , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento
4.
Biochem Biophys Res Commun ; 467(4): 766-70, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26478433

RESUMEN

Health policy precludes neonatal vaccination against influenza. Hence, morbidity and mortality are high under 6 months of age. Lactoferrin may activate diminished numbers of dysfunctional dendritic cells and reverse neonatal vaccine failures. Aluminum hydroxide/ALUM recruits neutrophils that secrete lactoferrin at deposition sites of antigen. We theorized lactoferrin + influenza antigen initiates an equivalent antibody response compared to ALUM. Three-day-old mice received subcutaneously 30 µg of H1N1 hemagglutinin + 200 µg of bovine lactoferrin versus hemagglutinin + ALUM. Controls received hemagglutinin, lactoferrin, or ALUM. After 21 days, sera measured anti-H1N1 (ELISA) and neutralizing antibody (plaque assays). ELISA detected equal antibody production with lactoferrin + hemagglutinin compared to hemagglutinin + ALUM; both sera also neutralized H1N1 virus at a 1:20 dilution (p < 0.01). Controls had no anti-H1N1 antibody. Neonates given lactoferrin had no anaphylaxis when challenged four weeks later. Lactoferrin is a safe and effective adjuvant for inducing antibody against influenza in neonates.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Lactoferrina/farmacología , Infecciones por Orthomyxoviridae/inmunología , Vacunación/métodos , Hidróxido de Aluminio/inmunología , Hidróxido de Aluminio/farmacología , Animales , Animales Recién Nacidos , Bovinos , Perros , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/farmacología , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Lactoferrina/inmunología , Células de Riñón Canino Madin Darby/virología , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/virología
5.
Neonatology ; 108(2): 137-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26159186

RESUMEN

BACKGROUND: Eosinophils infiltrate intestinal tissue during necrotizing enterocolitis (NEC) and adult bowel diseases. We theorized that epithelial damage causes eosinophilic activation and recruitment at NEC onset. OBJECTIVE: We studied the relationship between persistent blood eosinophilia and medical or surgical complications during NEC. METHODS: NEC cases and controls at MU Children's Hospital (2008-2013) underwent review. A Likert scale measured NEC severity. We utilized an SPSS database for statistical analyses. RESULTS: Of 50 NEC cases, infants in group 1 (n = 15) had eosinophilia <2 days after onset and those in group 2 (n = 25) had NEC but no persistent eosinophilia. Group 3 (n = 46) consisted of controls, i.e. infants without NEC matched for birth weight and gestational age and group 4 (n = 4) of preterm infants with infection and ≤5 days of eosinophilia. Hematologic assessment defined persistent eosinophilia as ≥5% eosinophils for ≥5 days after NEC onset. Absolute eosinophil counts were 2 times higher in group 1 than in group 2 (p = 0.002). The mean duration of eosinophilia was 8 days in group 1 versus 1 day in group 2 (p < 0.001). A Likert score of NEC severity was 3-fold higher in group 1 than in group 2 (p < 0.001). Compared to group 2, group 1 infants were 8 times more likely to have hepatic fibrosis or intestinal strictures. CONCLUSIONS: Early persistent blood eosinophilia is not currently a predictor of complications after the onset of NEC. This biomarker identifies immature infants at a high risk for adverse outcomes during NEC convalescence.


Asunto(s)
Citocinas/sangre , Enterocolitis Necrotizante/complicaciones , Eosinofilia/sangre , Recien Nacido Prematuro/sangre , Biomarcadores/sangre , Peso al Nacer , Bases de Datos Factuales , Femenino , Edad Gestacional , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Missouri , Pronóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
6.
J Immunol ; 195(2): 507-18, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-26034171

RESUMEN

Neonatal immunity exhibits weak Th1 but excessive Th2 responses, and the underlying mechanisms remain elusive. In this article, we show that neonatal basophils readily produce IL-4, a cytokine that proved to be pivotal in shaping the programs of both lymphocyte subsets. Besides promoting Th2 programs, IL-4 is captured by the IL-4 heteroreceptor (IL-4Rα/IL-13Rα1) expressed on dendritic cells and instigates IL-12 downregulation. Under these circumstances, differentiating Th1 cells upregulate IL-13Rα1, leading to an unusual expression of the heteroreceptor, which will serve as a death marker for these Th1 cells during rechallenge with Ag. The resulting Th1/Th2 imbalance impacts childhood immunity culminating in sensitivity to allergic reactions, susceptibility to microbial infection and perhaps poor efficacy of pediatric vaccines.


Asunto(s)
Basófilos/inmunología , Células Dendríticas/inmunología , Regulación del Desarrollo de la Expresión Génica/inmunología , Células TH1/inmunología , Células Th2/inmunología , Traslado Adoptivo , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos , Basófilos/citología , Basófilos/efectos de los fármacos , Basófilos/trasplante , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/trasplante , Femenino , Inmunidad Innata , Interleucina-12/genética , Interleucina-12/inmunología , Subunidad alfa1 del Receptor de Interleucina-13/genética , Subunidad alfa1 del Receptor de Interleucina-13/inmunología , Interleucina-4/genética , Interleucina-4/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Datos de Secuencia Molecular , Ovalbúmina/farmacología , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunología , Transducción de Señal , Células TH1/citología , Células TH1/efectos de los fármacos , Células TH1/trasplante , Células Th2/citología , Células Th2/efectos de los fármacos , Células Th2/trasplante
7.
Pediatr Res ; 77(1-2): 127-35, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25303278

RESUMEN

The conceptual framework for a gut-brain axis has existed for decades. The Human Microbiome Project is responsible for establishing intestinal dysbiosis as a mediator of inflammatory bowel disease, obesity, and neurodevelopmental disorders in adults. Recent advances in metagenomics implicate gut microbiota and diet as key modulators of the bidirectional signaling pathways between the gut and brain that underlie neurodevelopmental and psychiatric disorders in adults. Evidence linking intestinal dysbiosis to neurodevelopmental disease outcomes in preterm infants is emerging. Recent clinical studies show that intestinal dysbiosis precedes late-onset neonatal sepsis and necrotizing enterocolitis in intensive care nurseries. Moreover, strong epidemiologic evidence links late-onset neonatal sepsis and necrotizing enterocolitis in long-term psychomotor disabilities of very-low-birth-weight infants. The notion of the gut-brain axis thereby supports that intestinal microbiota can indirectly harm the brain of preterm infants. In this review, we highlight the anatomy and physiology of the gut-brain axis and describe transmission of stress signals caused by immune-microbial dysfunction in the gut. These messengers initiate neurologic disease in preterm infants. Understanding neural and humoral signaling through the gut-brain axis will offer insight into therapeutic and dietary approaches that may improve the outcomes of very-low-birth-weight infants.


Asunto(s)
Encéfalo/fisiología , Tracto Gastrointestinal/microbiología , Tracto Gastrointestinal/fisiología , Enfermedades del Recién Nacido/microbiología , Microbiota/fisiología , Modelos Biológicos , Transducción de Señal/fisiología , Disbiosis/microbiología , Enterocolitis Necrotizante/microbiología , Humanos , Recién Nacido , Recién Nacido de muy Bajo Peso , Sepsis/microbiología
8.
Curr Opin Pediatr ; 26(2): 146-50, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24503532

RESUMEN

PURPOSE OF REVIEW: There is an intense interest among neonatal caregivers as to whether lactoferrin given enterally may reduce the incidence of necrotizing enterocolitis in preterm infants. This review presents scientific and clinical evidence that lactoferrin alleviates or prevents this life-threatening disease. RECENT FINDINGS: Preclinical studies in neonatal rats showed that lactoferrin given orally before enteral infection with pathogenic Escherichia coli reduced bacteremia and mortality. A multicentered clinical trial found that very low-birth weight preterm infants given bovine lactoferrin had a significant reduction in late-onset sepsis; there was also a trend towards a diminished incidence of necrotizing enterocolitis. Although multicentered trials of lactoferrin use in preterm infants are near completion, regulatory burdens required to bring lactoferrin to the bedside may limit its availability. SUMMARY: Extremely preterm infants should receive colostrum, a natural lactoferrin concentrate, immediately after birth and, ideally, continue on breast milk throughout the hospital stay. This practice appears well tolerated, but additional experience will tell us whether this practice reduces the prevalence of necrotizing enterocolitis.


Asunto(s)
Calostro , Enterocolitis Necrotizante/prevención & control , Tracto Gastrointestinal/inmunología , Inflamación/inmunología , Lactoferrina/uso terapéutico , Sepsis/prevención & control , Animales , Nutrición Enteral , Enterocolitis Necrotizante/inmunología , Humanos , Inmunidad Innata , Incidencia , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/prevención & control , Recién Nacido de muy Bajo Peso , Lactoferrina/administración & dosificación , Lactoferrina/inmunología , Ensayos Clínicos Controlados Aleatorios como Asunto , Sepsis/inmunología
9.
JPEN J Parenter Enteral Nutr ; 38(6): 711-6, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23963690

RESUMEN

BACKGROUND: Preliminary studies suggest that fish-oil lipid emulsion given parenterally to very preterm infants reduces the severity of retinopathy (ROP) and cholestasis. METHODS: Infants weighing <1250 g at birth were randomly allocated to 2 groups: an experimental group of 60 infants that received an intravenous (IV) soybean, olive oil, and fish oil emulsion, and a control group of 70 infants that was given a parenteral soybean and olive oil emulsion. Plasma and erythrocyte concentrations of docosahexaenoic acid (DHA) were determined using a high-performance liquid chromatography-mass spectrometry analysis. RESULTS: Nine infants in the fish oil group required laser therapy for ROP compared with 22 infants in the standard intralipid group (risk ratio [RR], 0.48; 95% confidence interval [CI], 0.24-0.96). Three infants in the fish oil group developed cholestasis compared with 20 infants in the standard intralipid group (RR, 0.18; 95% CI, 0.055-0.56). The mean plasma DHA concentrations in treated infants were 2.9-fold higher in the fish oil group than in control infants on the 7th and 14th days of life. The mean DHA content in erythrocytes of treated infants was 4.5-fold and 2.7-fold higher compared with controls at 7 and 14 days of age. CONCLUSIONS: Premature infants receiving an IV fat emulsion containing fish oil had less ROP requiring laser treatment and less cholestasis than those receiving a standard lipid emulsion. These infants also had higher plasma and erythrocyte DHA levels at 7 and 14 days, suggesting potential long-term neurodevelopmental benefits.


Asunto(s)
Emulsiones Grasas Intravenosas/uso terapéutico , Aceites de Pescado/uso terapéutico , Recién Nacido de muy Bajo Peso , Retinopatía de la Prematuridad/prevención & control , Desarrollo Infantil/efectos de los fármacos , Colestasis/sangre , Colestasis/prevención & control , Ácidos Docosahexaenoicos/sangre , Ácidos Docosahexaenoicos/uso terapéutico , Emulsiones/uso terapéutico , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Aceite de Oliva , Nutrición Parenteral/métodos , Fosfolípidos/uso terapéutico , Aceites de Plantas/uso terapéutico , Estudios Prospectivos , Retinopatía de la Prematuridad/sangre , Aceite de Soja/uso terapéutico , Resultado del Tratamiento
10.
Neonatology ; 105(1): 14-24, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24193200

RESUMEN

The aim of this article is to educate neonatal caregivers about metagenomics. This scientific field uses novel and ever changing molecular methods to identify how infants become colonized with microbes after birth. Publications using metagenomics appear infrequently in the neonatal literature because clinicians are unaccustomed to the analytical techniques, data interpretation, and illustration of the results. This review covers those areas. After a brief introduction of neonatal citations forthcoming from metagenomic studies, the following topics are covered: (1) the history of metagenomics, (2) a description of current and emerging instruments used to define microbial populations in human organs, and (3) how extensive databases generated by genome analyzers are examined and presented to readers. Clinicians may feel like they are learning a new language; however, they will appreciate this task is essential to understanding and practicing neonatal medicine in the future.


Asunto(s)
Investigación Biomédica/tendencias , Microbiota/genética , Neonatología/educación , Humanos , Recién Nacido , Metagenómica/métodos , Filogenia , Análisis de Secuencia de ADN/métodos
11.
Eur J Immunol ; 44(3): 842-55, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24281978

RESUMEN

In this study, we examined the role IL-13 receptor alpha 1 (IL-13Rα1) plays in macrophage differentiation and function. The findings indicate that IL-13Rα1 is expressed on the M2 but not on the M1 subset of macrophages and specifically heterodimerizes with the IL-4Rα chain to form a type II receptor, which controls the differentiation and function of these cells. Indeed, BM cells from IL-13Rα1(+/+) and IL-13Rα1(-/-) mice yield equivalent numbers of macrophages when cultured under M2 polarizing conditions. However, IL-13Rα1(-/-) BM cells yield a much higher number of macrophages than IL-13Rα1(+/+) BM cells when the differentiation is carried out under M1-polarizing conditions. Further analyses indicated that macrophages that express IL-13Rα1 also display surface markers associated with an M2 phenotype. In addition, the IL-13Rα1(+) macrophages were highly efficient in phagocytizing zymosan bioparticles both in vitro and in vivo, and supported differentiation of naïve T cells to a Th2 phenotype. Finally, when stimulated by IL-13, a cytokine that uses the heteroreceptor, the cells were able to phosphorylate STAT6 efficiently. These previously unrecognized findings indicate that IL-13Rα1 serves as a marker for M2 macrophages and the resulting heteroreceptor influences both their differentiation and function.


Asunto(s)
Subunidad alfa1 del Receptor de Interleucina-13/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Expresión Génica , Inmunofenotipificación , Interleucina-13/farmacología , Subunidad alfa1 del Receptor de Interleucina-13/genética , Macrófagos/citología , Macrófagos/efectos de los fármacos , Ratones , Ratones Noqueados , Monocitos/inmunología , Monocitos/metabolismo , Fenotipo , Fosforilación/efectos de los fármacos , Carácter Cuantitativo Heredable , Factor de Transcripción STAT6/metabolismo
12.
Clin Perinatol ; 40(1): 79-91, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23415265

RESUMEN

Lactoferrin (LF) is a multifunctional protein and a member of the transferrin family. LF and lysozyme in breast milk kill bacteria. In the stomach, pepsin digests and releases a potent peptide antibiotic called lactoferricin from native LF. The antimicrobial characteristics of LF may facilitate a healthy intestinal microbiome. LF is the major whey in human milk; its highest concentration is in colostrum. This fact highlights early feeding of colostrum and also fresh mature milk as a way to prevent necrotizing enterocolitis.


Asunto(s)
Calostro/metabolismo , Enterocolitis Necrotizante/prevención & control , Intestino Delgado/inmunología , Lactoferrina/metabolismo , Leche Humana/metabolismo , Animales , Calostro/inmunología , Enterocolitis Necrotizante/terapia , Humanos , Recién Nacido , Intestino Delgado/microbiología , Lactoferrina/inmunología , Lactoferrina/uso terapéutico , Metagenoma/inmunología , Leche/metabolismo , Leche Humana/química , Leche Humana/inmunología , Muramidasa/inmunología
14.
Neonatology ; 103(1): 10-20, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23006982

RESUMEN

Current models of necrotizing enterocolitis (NEC) propose that intraluminal microbes destroy intestinal mucosa and activate an inflammatory cascade that ends in necrosis. We suggest an alternate hypothesis wherein NEC is caused by injury to Paneth cells (PCs) in the intestinal crypts. PCs are specialized epithelia that protect intestinal stem cells from pathogens, stimulate stem cell differentiation, shape the intestinal microbiota, and assist in repairing the gut. Our novel model of NEC uses neonatal mice and ablates PCs followed by enteral infection. We contrast this model with other animal examples of NEC and the clinical disease. Selective destruction of PCs using dithizone likely releases tumor necrosis factor-α and other inflammatory mediators. We propose that this event produces inflammation in the submucosa, generates platelet-activating factor, and induces a coagulopathy. The role of PCs in NEC is consistent with the onset of disease in preterm infants after a period of PC-related maturation, the central role of PCs in crypt-related homeostasis, the anatomic location of pneumatosis intestinalis close to the crypts, and the proximity of PCs to occluded blood vessels that cause coagulation necrosis of the intestinal villi. We offer this hypothesis to promote new thoughts about how NEC occurs and its potential prevention.


Asunto(s)
Enterocolitis Necrotizante/etiología , Células de Paneth/patología , Células de Paneth/fisiología , Animales , Formación de Concepto , Enfermedad/etiología , Enterocolitis Necrotizante/patología , Enterocolitis Necrotizante/prevención & control , Salud , Humanos , Recién Nacido , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Ratones , Modelos Biológicos
15.
Pediatr Res ; 71(5): 546-51, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22322385

RESUMEN

INTRODUCTION: Necrotizing enterocolitis (NEC) is a devastating disease of premature infants. Probiotics decrease the risk of NEC in clinical and experimental studies. Antimicrobial peptides protect the gut against noxious microbes and shape the commensal microbiota, but their role in NEC remains unclear. METHODS: To investigate the expression of antimicrobial peptides in experimental NEC and the impact of probiotics on their expression, premature rats were divided into three groups: dam fed (DF), hand fed with formula (FF), or hand fed with formula containing Bifidobacterium bifidum (FF + BIF). All groups were exposed to asphyxia and cold stress. RESULTS: Like in human ontogeny, the rat pup has low expression of Paneth cell antimicrobials, which increases rapidly during normal development. The expression of lysozyme, secretory phospholipase A(2) (sPLA(2)), pancreatic-associated proteins 1 and 3 mRNA was elevated in the FF group with a high incidence of NEC, as compared with the DF and FF + BIF groups where the disease was attenuated. DISCUSSION: We conclude that induction of antimicrobial peptides occurs in experimental NEC similar to that reported in human disease and is attenuated when disease is averted by probiotic B. bifidum. The induction of antimicrobial peptides is likely an adaptive mucosal response that is often not sufficient to prevent disease in the premature gut.


Asunto(s)
Bifidobacterium , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/microbiología , Péptidos/metabolismo , Probióticos , Proteínas/metabolismo , Animales , Animales Recién Nacidos , Antiinfecciosos , Secuencia de Bases , Cartilla de ADN , Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/terapia , Expresión Génica , Inmunohistoquímica , Péptidos/genética , Reacción en Cadena de la Polimerasa , Proteínas/genética , Ratas , Ratas Sprague-Dawley
16.
Dis Model Mech ; 5(4): 522-32, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22328592

RESUMEN

Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality in premature infants. During NEC pathogenesis, bacteria are able to penetrate innate immune defenses and invade the intestinal epithelial layer, causing subsequent inflammation and tissue necrosis. Normally, Paneth cells appear in the intestinal crypts during the first trimester of human pregnancy. Paneth cells constitute a major component of the innate immune system by producing multiple antimicrobial peptides and proinflammatory mediators. To better understand the possible role of Paneth cell disruption in NEC, we quantified the number of Paneth cells present in infants with NEC and found that they were significantly decreased compared with age-matched controls. We were able to model this loss in the intestine of postnatal day (P)14-P16 (immature) mice by treating them with the zinc chelator dithizone. Intestines from dithizone-treated animals retained approximately half the number of Paneth cells compared with controls. Furthermore, by combining dithizone treatment with exposure to Klebsiella pneumoniae, we were able to induce intestinal injury and inflammatory induction that resembles human NEC. Additionally, this novel Paneth cell ablation model produces NEC-like pathology that is consistent with other currently used animal models, but this technique is simpler to use, can be used in older animals that have been dam fed, and represents a novel line of investigation to study NEC pathogenesis and treatment.


Asunto(s)
Enterocolitis Necrotizante/microbiología , Enterocolitis Necrotizante/patología , Intestino Delgado/microbiología , Intestino Delgado/patología , Klebsiella pneumoniae/fisiología , Células de Paneth/microbiología , Células de Paneth/patología , Envejecimiento/patología , Animales , Diferenciación Celular/efectos de los fármacos , Gránulos Citoplasmáticos/metabolismo , Modelos Animales de Enfermedad , Ditizona , Nutrición Enteral , Enterocolitis Necrotizante/complicaciones , Enterocolitis Necrotizante/tratamiento farmacológico , Humanos , Recién Nacido , Inflamación/complicaciones , Inflamación/microbiología , Inflamación/patología , Intestino Delgado/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Ratones , Células de Paneth/efectos de los fármacos , Zinc/farmacología , Zinc/uso terapéutico
19.
Clin Perinatol ; 37(3): 565-79, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20813271

RESUMEN

Bacterial translocation from the gastrointestinal tract is an important pathway initiating late-onset sepsis and necrotizing enterocolitis in very low-birth-weight infants. The emerging intestinal microbiota, nascent intestinal epithelia, naive immunity, and suboptimal nutrition (lack of breast milk) have roles in facilitating bacterial translocation. Feeding lactoferrin, probiotics, or prebiotics has presented exciting possibilities to prevent bacterial translocation in preterm infants, and clinical trials will identify the most safe and efficacious prevention and treatment strategies.


Asunto(s)
Traslocación Bacteriana , Enterocolitis Necrotizante/prevención & control , Mucosa Intestinal/microbiología , Intestinos/microbiología , Probióticos/uso terapéutico , Enterocolitis Necrotizante/microbiología , Humanos , Recién Nacido
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