RESUMEN
Lynch syndrome is an inherited cancer predisposition syndrome caused by germline defects in any of the mismatch repair (MMR) genes. Diagnosis of carriers makes precision prevention, early detection, and tailored treatment possible. Herein we report a novel founder deletion of 18,758 bp, mediated by Alu repeats on both sides, detected in Ethiopian Jews. The deletion, which encompasses exon 9-10 of the MSH2 coding sequence, is associated mainly with early-onset MSH2/MSH6-deficient colorectal cancer (CRC) and liposarcoma. Testing of 35 members of 5 seemingly unrelated families of Ethiopian origin yielded 10/21 (48%) carriers, of whom 9 had CRC. Age at first tumor diagnosis ranged from 16 to 89 years. Carriers from the oldest generations were diagnosed after age 45 years (mean 57), and carriers from the younger generation were diagnosed before age 45 years (mean 30). Awareness of this founder deletion is important to improve patient diagnosis, institute surveillance from an early age, and refer patients for genetic counseling addressing the risk of bi-allelic constitutional MMR deficiency syndrome.
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Neoplasias Colorrectales Hereditarias sin Poliposis , Neoplasias Colorrectales , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Reparación de la Incompatibilidad de ADN/genética , Etiopía , Mutación de Línea Germinal , Humanos , Judíos/genética , Persona de Mediana Edad , Proteína 2 Homóloga a MutS/genética , Adulto JovenRESUMEN
Nearly 20,000 pediatric patients undergo cholecystectomy annually, and abnormal gallbladder emptying ("biliary dyskinesia") has replaced cholelithiasis as the leading indication for this operation in the USA. Nonetheless, patients with abnormal gallbladder emptying nuclear medicine scans do not uniformly benefit from cholecystectomy. This article reviews the available data on presentation, workup and treatment of patients with abnormally low and high rates of gallbladder emptying.
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Discinesia Biliar/diagnóstico , Discinesia Biliar/terapia , Colecistectomía , Discinesia Biliar/tratamiento farmacológico , Discinesia Biliar/cirugía , HumanosRESUMEN
Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes.
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Algoritmos , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Incontinencia Fecal/cirugía , Enfermedad de Hirschsprung/cirugía , Complicaciones Posoperatorias/prevención & control , Guías de Práctica Clínica como Asunto , Niño , Incontinencia Fecal/etiología , Enfermedad de Hirschsprung/complicaciones , Humanos , Periodo Posoperatorio , Resultado del TratamientoRESUMEN
PURPOSE: To examine the effects of obesity on specialty-specific surgical outcomes in children. MATERIALS AND METHODS: Retrospective cohort study using the National Surgical Quality Improvement Program, Pediatric, 2012-2014. Patients included those aged 2-17 years who underwent a surgical procedure in one of six specialties. Obesity was the primary patient variable of interest. Outcomes of interest were postoperative complications and operative times. Odds ratios for development of postoperative complications were calculated using stepwise multivariate regression analysis. RESULTS: Obesity was associated with a significantly greater risk of wound complications (OR 1.24, 95% CI 1.13-1.36), but decreased risk of non-wound complications (OR 0.68, 95% CI 0.63-0.73) and morbidity (OR 0.79, 95% CI 0.75-0.84). Obesity was not a significant factor in predicting postoperative complications in patients undergoing otolaryngology or plastic surgery procedures. Anesthesia times and operative times were significantly longer for obese patients undergoing most types of pediatric surgical procedures. CONCLUSION: Obesity confers an increased risk of wound complications in some pediatric surgical specialties and is associated with overall decreased non-wound complications and morbidity. These findings suggest that the relationship between obesity and postoperative complications is complex and may be more dependent on underlying procedure- or specialty-related factors than previously suspected.
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Índice de Masa Corporal , Obesidad/complicaciones , Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias/etiología , Medición de Riesgo/métodos , Procedimientos Quirúrgicos Operativos , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Morbilidad/tendencias , Oportunidad Relativa , Tempo Operativo , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Cesarean delivery is the most common surgical procedure performed in the USA. We evaluated the postoperative analgesic properties of neuraxial hydromorphone compared to neuraxial morphine for post-cesarean delivery analgesia. METHODS: A retrospective chart review was performed of women who underwent cesarean delivery and received neuraxial anesthesia from March to November 2011 and from March to November 2012. A total of 450 patients received intrathecal morphine 200µg and 387 patients received intrathecal hydromorphone 60µg. Eighty-one patients received epidural morphine 3mg and 102 patients received epidural hydromorphone 0.6mg. RESULTS: Median time to first opioid after intrathecal morphine was 17.0h versus 14.6h after intrathecal hydromorphone (P<0.0001). Patients who received intrathecal hydromorphone consumed more opioids in the first 24h; 37.0mg versus 26.4mg oral morphine equivalents (P<0.001). The side effect profile between the intrathecal groups was similar. Median time to first opioid with epidural morphine was 20.1h versus 13.0h with epidural hydromorphone (P=0.0007). Total opioid consumption was not significantly different between the epidural groups. The side effect profiles were similar. CONCLUSIONS: Hydromorphone is a reasonable alternative to morphine for post-cesarean delivery analgesia. With the dosing used in our study, analgesia from morphine lasted longer than hydromorphone via intrathecal and epidural routes; however, neuraxial hydromorphone remains a reasonable option for long-acting analgesia post cesarean delivery.
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Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Cesárea/efectos adversos , Hidromorfona/administración & dosificación , Hidromorfona/uso terapéutico , Morfina/administración & dosificación , Morfina/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Analgesia Epidural , Analgésicos Opioides/efectos adversos , Femenino , Humanos , Hidromorfona/efectos adversos , Inyecciones Espinales , Morfina/efectos adversos , Embarazo , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.
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Enfermedad de Hirschsprung/cirugía , Obstrucción Intestinal/diagnóstico , Obstrucción Intestinal/terapia , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/terapia , Toxinas Botulínicas/uso terapéutico , Niño , Preescolar , Enema , Femenino , Enfermedad de Hirschsprung/complicaciones , Humanos , Lactante , Obstrucción Intestinal/etiología , Masculino , Guías de Práctica Clínica como AsuntoRESUMEN
Apart from their role in humoral immunity, B cells can exhibit IL-10-dependent regulatory activity (Bregs). These regulatory subpopulations have been shown to inhibit inflammation and allograft rejection. However, our understanding of Bregs has been hampered by their rarity, lack of a specific marker, and poor insight into their induction and maintenance. We previously demonstrated that T cell immunoglobulin mucin domain-1 (TIM-1) identifies over 70% of IL-10-producing B cells, irrespective of other markers. We now show that TIM-1 is the primary receptor responsible for Breg induction by apoptotic cells (ACs). However, B cells that express a mutant form of TIM-1 lacking the mucin domain (TIM-1(Δmucin) ) exhibit decreased phosphatidylserine binding and are unable to produce IL-10 in response to ACs or by specific ligation with anti-TIM-1. TIM-1(Δmucin) mice also exhibit accelerated allograft rejection, which appears to be due in part to their defect in both baseline and induced IL-10(+) Bregs, since a single transfer of WT TIM-1(+) B cells can restore long-term graft survival. These data suggest that TIM-1 signaling plays a direct role in Breg maintenance and induction both under physiological conditions (in response to ACs) and in response to therapy through TIM-1 ligation. Moreover, they directly demonstrate that the mucin domain regulates TIM-1 signaling.
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Linfocitos B Reguladores/citología , Proteínas de la Membrana/metabolismo , Transducción de Señal , Animales , Supervivencia de Injerto , Receptor Celular 1 del Virus de la Hepatitis A , Interleucina-10/biosíntesis , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos BALB CRESUMEN
B cells play a complex role in the immune response. In addition to giving rise to plasma cells (PCs) and promoting T cell responses via antigen presentation, they perform immunoregulatory functions. This knowledge has created concerns regarding nonspecific B cell depletional therapy because of the potential to paradoxically augment immune responses. Recent studies now indicate that PCs have immune functions beyond immunoglobulin synthesis. Evidence for a new role for PCs as potent regulatory cells (via IL-10 and IL-35 production) is discussed including the implications for PC-targeted therapies currently being developed for clinical transplantation.
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Presentación de Antígeno/inmunología , Enfermedades Autoinmunes/inmunología , Linfocitos B/inmunología , Enfermedades Transmisibles/inmunología , Células Plasmáticas/inmunología , Anticuerpos Monoclonales/uso terapéutico , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Transmisibles/tratamiento farmacológico , Humanos , PronósticoRESUMEN
A general combined purification and immobilization method to facilitate biocatalytic process development is presented. The support material, EziG™, is based on controlled porosity glass (CPG) or polymer-coated versions thereof (HybCPG) and binds protein affinity tags. Biocatalytic reactions in aqueous and organic media with seven enzymes of biocatalytic interest are shown.
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Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Biocatálisis , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Vidrio , Lipasa/química , Lipasa/metabolismo , Oxigenasas/química , Oxigenasas/metabolismo , Polímeros/química , Porosidad , Esterol Esterasa/química , Esterol Esterasa/metabolismo , Transaminasas/química , Transaminasas/metabolismoRESUMEN
Antibody-mediated rejection (ABMR) represents a significant clinical challenge for solid organ transplantation. Mechanistic understanding of ABMR is incomplete and diagnostic accuracy for ABMR is limited, and as a result, targeted treatment remains elusive and new treatment modalities are difficult to validate. Three hundred twenty-six participants from 15 countries met for the first Cutting Edge of Transplantation (CEOT) symposium organized by the American Society of Transplantation (AST) in Chandler, Arizona, February 14-16, 2013. During the 3-day interactive symposium, presentations, moderated poster sessions and round table discussions addressed cutting edge knowledge of B and plasma cell biology, mechanisms of antibody-mediated tissue injury, advances and limitations in ABMR diagnostics, as well as current and potential new treatment options for ABMR. The outcome of the meeting identified the following unmet needs for: (a) improved understanding of the regulation of B cell maturation and antibody response to enable targeted therapies; (b) more precise diagnostics of ABMR, including molecular pathology, risk stratification by sensitive antibody testing and monitoring of treatment effects; and (c) innovative multicenter trial designs that enhance observational power, in particular, in assessing synergistic multimodality therapies with reduced toxicities.
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Formación de Anticuerpos/inmunología , Linfocitos B/inmunología , Rechazo de Injerto/inmunología , Isoanticuerpos/inmunología , Trasplante de Órganos , Informe de Investigación , Rechazo de Injerto/prevención & control , HumanosRESUMEN
The immune system is comprised of several CD4(+) T regulatory (Treg) cell types, of which two, the Foxp3(+) Treg and T regulatory type 1 (Tr1) cells, have frequently been associated with transplant tolerance. However, whether and how these two Treg-cell types synergize to promote allograft tolerance remains unknown. We previously developed a mouse model of allogeneic transplantation in which a specific immunomodulatory treatment leads to transplant tolerance through both Foxp3(+) Treg and Tr1 cells. Here, we show that Foxp3(+) Treg cells exert their regulatory function within the allograft and initiate engraftment locally and in a non-antigen (Ag) specific manner. Whereas CD4(+) CD25(-) T cells, which contain Tr1 cells, act from the spleen and are key to the maintenance of long-term tolerance. Importantly, the role of Foxp3(+) Treg and Tr1 cells is not redundant once they are simultaneously expanded/induced in the same host. Moreover, our data show that long-term tolerance induced by Foxp3(+) Treg-cell transfer is sustained by splenic Tr1 cells and functionally moves from the allograft to the spleen.
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Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/inmunología , Bazo/inmunología , Linfocitos T Reguladores/inmunología , Tolerancia al Trasplante/inmunología , Traslado Adoptivo , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD4/inmunología , Antígenos CD4/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Factores de Transcripción Forkhead/inmunología , Factores de Transcripción Forkhead/metabolismo , Supervivencia de Injerto , Islotes Pancreáticos/metabolismo , Antígenos Comunes de Leucocito/inmunología , Antígenos Comunes de Leucocito/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Bazo/metabolismo , Linfocitos T Reguladores/metabolismo , Trasplante HomólogoRESUMEN
Inbreeding depression and lack of genetic diversity in inbred mice could mask unappreciated causes of graft failure or remove barriers to tolerance induction. To test these possibilities, we performed heart transplantation between outbred or inbred mice. Unlike untreated inbred mice in which all allografts were rejected acutely (6-16 days posttransplantation), untreated outbred mice had heterogeneous outcomes, with grafts failing early (<4 days posttransplantation), acutely (6-24 days) or undergoing chronic rejection (>75 days). Blocking T cell costimulation induced long-term graft acceptance in both inbred and outbred mice, but did not prevent the early graft failure observed in the latter. Further investigation of this early phenotype established that it is dependent on the donor, and not the recipient, being outbred and that it is characterized by hemorrhagic necrosis and neutrophilic vasculitis in the graft without preformed, high titer antidonor antibodies in the recipient. Complement or neutrophil depletion prevented early failure of outbred grafts, whereas transplanting CD73-deficient inbred hearts, which are highly susceptible to ischemia-reperfusion injury, recapitulated the early phenotype. Therefore, outbred mice could provide broader insight into donor and recipient determinants of allograft outcomes but their hybrid vigor and genetic diversity do not constitute a uniform barrier to tolerance induction.
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Cruzamiento , Rechazo de Injerto/inmunología , Supervivencia de Injerto/fisiología , Trasplante de Corazón , Tolerancia Inmunológica/inmunología , Daño por Reperfusión/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Aptitud Genética/fisiología , Rechazo de Injerto/mortalidad , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Daño por Reperfusión/mortalidad , Tasa de Supervivencia , Trasplante HomólogoRESUMEN
Graft outcomes after kidney transplantation continue to be adversely affected by ischemia-reperfusion injury and rejection. High-resolution, real-time imaging of the transplanted kidney could shed valuable insights into these dynamic processes, but such methodology has not been established. Here we describe a technique for intravital imaging of the transplanted mouse kidney using multiphoton fluorescence microscopy. The technique enabled real-time, high-resolution imaging and quantitation of renal filtration, cell death, leukocyte adhesion and capillary blood flow after transplantation. Using this technique, we found that brief graft ischemia associated with the transplantation procedure led to a rapid decline in renal filtration accompanied by a significant increase in microvascular leakage and renal tubular epithelial cell death within the first 3 h after transplantation. No significant changes in leukocyte adhesion or capillary blood flow were observed during the same time period. This report establishes multiphoton fluorescence microscopy as a sensitive tool for simultaneously studying functional and structural perturbations that occur in the mouse kidney after transplantation and for investigating the migration of leukocytes to the graft.
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Trasplante de Riñón , Riñón/patología , Cuerpo Vítreo , Animales , Riñón/metabolismo , Ratones , Ratones Endogámicos C57BL , Microscopía FluorescenteRESUMEN
Type I interferons (IFN-I) link innate to adaptive immunity in microbial infection, autoimmune disease and tumor immunity. It is not known whether IFN-I have an equally central role in alloimmunity. Here we tested this possibility by studying skin allograft survival and donor-specific CD8+ T-cell responses in mice that lack the IFN-I receptor (IFN-IR-/-). We found that IFN-IR-/- mice reject fully allogeneic wild-type skin grafts at the same rate as wild-type recipients. Similarly, allograft rejection was not delayed if IFN-IR-/- male skin was transplanted to syngeneic IFN-IR-/- female mice. Quantitation of the male (H-Y)-specific CD8+ T-cell response in these mice revealed normal generation of donor-specific CD8+ effector T cells but fourfold reduction in CD8+ memory T cells. Memory CD8+ T cells generated in the absence of IFN-IR had normal phenotype and recall function, assessed by ex vivo cytokine production and the ability of IFN-IR-/- mice to mount second set rejection. Finally, these memory T cells were maintained at a constant number despite their inability to respond to IFN-1. Our findings indicate that IFN-I cytokines are not critical for acute allograft rejection or for the expansion and differentiation of donor-specific CD8+ T cells into long-lived, functional memory T cells.
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Linfocitos T CD8-positivos/inmunología , Rechazo de Injerto/inmunología , Interferón Tipo I/inmunología , Trasplante de Piel/inmunología , Animales , Femenino , Rechazo de Injerto/etiología , Memoria Inmunológica , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Receptores de Interferón/inmunología , Trasplante HomólogoRESUMEN
Pain is one of the major complaints leading to doctor visits. Therefore basic knowledge of frequent pain diagnoses and possible treatment approaches is essential. Numerous medical and interventional therapeutic options are available for causal or symptomatic treatment of pain. The treatment of neuropathic pain is often difficult and demands special knowledge. Antidepressants like amitriptyline and anticonvulsive drugs are the first choice in these cases. Also interventional approaches are useful, such as spinal cord stimulation for angina pectoris. For the treatment of complex regional pain syndrome and phantom pain the use of mirror feed-back is a new effective method for pain relief. The only way to prevent from development of chronic pain is the early and effective treatment of acute pain.
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Analgésicos/uso terapéutico , Anticonvulsivantes/uso terapéutico , Antidepresivos/uso terapéutico , Biorretroalimentación Psicológica/métodos , Manejo del Dolor , Dolor/diagnóstico , Terapia por Estimulación Eléctrica , HumanosRESUMEN
Acute or chronic pain are the most frequent reasons to seek medical help. Primarily acute pain is a symptom and warning sign. However, insufficient treatment of acute pain may induce a change to a chronic long lasting pain illness. Therefore a consequent immediate treatment is essential. Chronic pain is a bio-psycho-social illness. In this situation pharmacotherapy or any other monotherapy alone is no longer effective. Interdisciplinary treatment is needed. Effective treatment of acute pain to prevent from long lasting pain episodes is an essential and the only way to prevent from enormous financial consequences of chronic pain.
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Manejo del Dolor , Dolor/diagnóstico , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina/tendencias , Enfermedad Crónica , Alemania , Grupo de Atención al PacienteRESUMEN
Antimicrobial peptides are a source of novel agents that could be useful for treatment of the chronic lung infections that afflict cystic fibrosis (CF) patients. Efficacy depends on antimicrobial activity against the major pathogens of CF patients, Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in the environment of the CF patient's airway. We describe the in vitro efficacies of derivatives of histatins, which are histidine-rich peptides produced by the salivary glands of humans and higher primates. P-113, a peptide containing 12 of the 24 amino acid residues of the parent molecule, histatin 5, retained full antibacterial activity and had a good spectrum of activity in vitro against the prominent pathogens of CF patients. However, P-113 was not active in the presence of purulent sputum from CF patients. In contrast, P-113D, the mirror-image peptide with the amino acid residues in the D configuration, was stable in sputum, was as active as P-113 against pathogens of CF patients in the absence of sputum and retained significant activity in the presence of sputum from CF patients. Recombinant human DNase, which effectively liquefies sputum, enhanced the activity of P-113D in undiluted sputum against both exogenous (added) bacteria and endogenous bacteria. Because of its properties, P-113D shows potential as an inhalant in chronic suppressive therapy for CF patients.
Asunto(s)
Antibacterianos/farmacología , Fibrosis Quística/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Saralasina/farmacología , Esputo/microbiología , Fibrosis Quística/complicaciones , Fibrosis Quística/metabolismo , Desoxirribonucleasas/farmacología , Humanos , Isomerismo , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/microbiología , Saralasina/química , Esputo/química , EstereoisomerismoRESUMEN
Metal ions were evaluated as potential antimicrobial agents suitable for local delivery in the oral cavity for the treatment of periodontitis. Silver nitrate, copper chloride, and zinc chloride were tested for antimicrobial activity in in vitro killing assays conducted in phosphate buffered saline with a series of oral bacteria including gram-negative periodontal pathogens and gram-positive streptococci. Copper and zinc salts failed to exhibit strong and consistent activity against periodontal pathogens. In contrast, silver at a concentration of 0.5 microg/mL produced a 3 log10 reduction in colony forming units (CFU)/mL or greater against all periodontal pathogens tested including Porphyromonas gingivalis, Prevotella intermedia, Prevotella denticola, Bacteroides forsythus, Fusobacterium nucleatum vincentii, Campylobacter gracilis, Campylobacter rectus, Eikenella corrodens, and Actinobacillus actinomycetemcomitans. In comparison, substantially higher concentrations of silver nitrate failed to kill oral streptococci. A silver nitrate concentration of 25 microg/mL produced log10 reductions in CFU/mL of 3.5-5 in killing assays performed in human serum against P. gingivalis, demonstrating the ability of silver to retain activity in a biological medium similar to that encountered in vivo in the periodontal pocket. These results identify silver nitrate, an antimicrobial that may possess advantages over traditional antibiotics, as a potential agent for controlled release local delivery in the oral cavity for the treatment of periodontitis.
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Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Periodontitis/microbiología , Nitrato de Plata/farmacología , Administración Tópica , Aggregatibacter actinomycetemcomitans/efectos de los fármacos , Bacteroides/efectos de los fármacos , Sangre , Campylobacter/efectos de los fármacos , Cloruros/farmacología , Recuento de Colonia Microbiana , Cobre/farmacología , Medios de Cultivo , Eikenella corrodens/efectos de los fármacos , Fusobacterium nucleatum/efectos de los fármacos , Humanos , Boca/microbiología , Bolsa Periodontal/microbiología , Porphyromonas gingivalis/efectos de los fármacos , Prevotella/efectos de los fármacos , Prevotella intermedia/efectos de los fármacos , Nitrato de Plata/administración & dosificación , Streptococcus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Streptococcus sobrinus/efectos de los fármacos , Compuestos de Zinc/farmacologíaRESUMEN
Through the analysis of a series of 25 peptides composed of various portions of the histatin 5 sequence, we have identified P-113, a 12-amino-acid fragment of histatin 5, as the smallest fragment that retains anticandidal activity comparable to that of the parent compound. Amidation of the P-113 C terminus increased the anticandidal activity of P-113 approximately twofold. The three histidine residues could be exchanged for three hydrophobic residues, with the fragment retaining anticandidal activity. However, the change of two or more of the five basic (lysine and arginine) residues to uncharged residues resulted in a substantial loss of anticandidal activity. A synthetic D-amino-acid analogue, P-113D, was as active against Candida albicans as the L-amino-acid form. In vitro MIC tests in low-ionic-strength medium showed that P-113 has potent activity against Candida albicans, Candida glabrata, Candida parapsilosis, and Candida tropicalis. These results identify P-113 as a potential antimicrobial agent in the treatment of oral candidiasis.
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Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Proteínas y Péptidos Salivales/farmacología , Saralasina/farmacología , Secuencia de Aminoácidos , Farmacorresistencia Microbiana , Histatinas , Humanos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Fragmentos de Péptidos/farmacología , Saralasina/química , Homología de Secuencia de AminoácidoRESUMEN
Cytolytic T lymphocyte-associated antigen 4 (CTLA-4) is a critical down-regulatory molecule in T cells that plays a major role in peripheral tolerance. Although the CD45 protein tyrosine phosphatase is a potent immunomodulatory target, the mechanisms by which antibody against CD45RB isoforms (anti-CD45RB) induces allograft tolerance remain unclear. We show here that anti-CD45RB treatment alters CD45 isoform expression on T cells, which is associated with rapid up-regulation of CTLA-4 expression. These effects appear specific and occur without up-regulation of other activation markers. Administration of a blocking monoclonal antibody to CTLA-4 at the time of transplantation prevents anti-CD45RB therapy from prolonging islet allograft survival. In addition, treatment with cyclosporin A blocks anti-CD45RB-induced CTLA-4 expression and promotes acute rejection. These data suggest that anti-CD45RB acts through mechanisms that include CTLA-4 up-regulation and demonstrate a link between CD45 and CTLA-4 that depends on calcineurin-mediated signaling. They demonstrate also that CTLA-4 expression may be specifically targeted to enhance allograft acceptance.