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1.
Psychiatry Res ; 334: 115787, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367453

RESUMO

Repetitive negative thinking (RNT) is a transdiagnostic symptom observed across mood and anxiety disorders and is characterized by frequent, distressing thoughts that are perceived as uncontrollable. Specific forms of RNT have been linked to increased suicide risk. However, most work examining links between RNT and suicide has been conducted within specific disorders and subtypes of RNT (e.g., rumination in individuals with depression). The present study aimed to investigate associations between transdiagnostic RNT and suicidal ideation. We hypothesized RNT would be associated with suicide risk beyond disorder-specific clinical symptoms. Fifty-four participants with mood, anxiety, and/or traumatic stress disorders completed an interview assessing suicidal risk (Columbia-Suicide Severity Rating Scale (C-SSRS)) and self-report questionnaires assessing transdiagnostic RNT, depression, and anxiety. Based on C-SSRS, we divided participants into high or low suicide risk groups. We analyzed the relationship between suicidal risk group and RNT and found that RNT was uniquely associated with suicidal risk group, controlling for depression and anxiety severity. Our results suggest including assessments of RNT may have clinical utility for understanding the degree of suicide risk in individuals and point to the potential utility of including clinical interventions to target this symptom for those at high risk of suicide.


Assuntos
Pessimismo , Humanos , Ideação Suicida , Ansiedade/diagnóstico , Transtornos de Ansiedade , Inquéritos e Questionários , Fatores de Risco
2.
Spine Deform ; 10(6): 1299-1306, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35809201

RESUMO

PURPOSE: To estimate the criterion validity of sagittal thoracolumbar spine measurement using a surface topography method in a clinical population against the gold standard and to estimate concurrent validity against two non-radiographic clinical tools. METHODS: In this cross-sectional validity study, thoracolumbar curvature was measured in adults with spinal conditions recruited from a specialist orthopaedic hospital. A surface topography method using a Kinect sensor was compared to three other measurement methods: spinal radiograph (gold standard), flexicurve and digital inclinometer. Correlation coefficients and agreement between the measurement tools were analysed. RESULTS: Twenty-nine participants (79% female) were included in criterion validity analyses and 38 (76% female) in concurrent validity analyses. The surface topography method was moderately correlated with the radiograph (r = .70, p < .001) in the thoracic spine, yet there was no significant correlation with the radiograph in the lumbar spine (r = .32, p = .89). The surface topography method was highly correlated with the flexicurve (rs = .91, p < .001) and digital inclinometer (r = .82, p < .001) in the thoracic spine, and highly correlated with the flexicurve (r = .74, p < .001) and digital inclinometer (r = .74, p < .001) in the lumbar spine. CONCLUSIONS: The surface topography method showed moderate correlation and agreement in thoracic spine with the radiograph (criterion validity) and high correlation with the flexicurve and digital inclinometer (concurrent validity). Compared with other non-radiographic tools, this surface topography method displayed similar criterion validity for kyphosis curvature measurement.


Assuntos
Cifose , Adulto , Humanos , Feminino , Masculino , Estudos Transversais , Reprodutibilidade dos Testes , Cifose/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Radiografia
4.
Tech Coloproctol ; 25(11): 1217-1224, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34499279

RESUMO

BACKGROUND: Diverting loop ileostomies (DLIs) are ideally reversed 6-12 weeks after the index operation. However, reversal surgery is frequently delayed in a real-world setting, with potential implications on patient's quality of life and postoperative complications. The aim of this study was to investigate the impact of timing of the reversal on patient outcomes at a tertiary referral hospital. METHODS: Consecutive patients who underwent elective reversal of loop ileostomy (RLI) between January 2007 and January 2019 were included. The primary outcomes were incidence of postoperative ileus (POI) and 30-day postoperative complications. RESULTS: Of 251 eligible patients, 158 (63%) were men, the median age was 64 years (range 23-88 years), and the most common index operation was an ultra-low anterior resection in 106 (42%). The median time to reversal for the entire cohort was 7.4 months (range 1-28). RLI was performed within 6 months after the index surgery in 89 patients (35%, early group), 6-12 months in 120 (48%, middle group) and after more than 12 months in 42 (17%, late group) patients. A significantly lower incidence of postoperative ileus (13.5% vs. 25.8% vs. 38.1%, p = 0.006), and 30-day postoperative complications (29.2% vs 41.7% vs. 57.1%, p = 0.011) were seen in the early group compared to the middle and late groups, respectively. There was no difference in the return to theater, length of hospital stay, and readmission rate between groups. CONCLUSION: Delayed RLI is associated with increased risk of postoperative complications.


Assuntos
Ileostomia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Ileostomia/efeitos adversos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Adulto Jovem
5.
Br J Surg ; 108(7): 797-803, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34136900

RESUMO

BACKGROUND: Recovery of gastrointestinal (GI) function is often delayed after colorectal surgery. Enhanced recovery protocols (ERPs) recommend routine laxative use, but evidence of benefit is unclear. This study aimed to investigate whether the addition of multimodal laxatives to an ERP improves return of GI function in patients undergoing colorectal surgery. METHODS: This was a single-centre, parallel, open-label RCT. All adult patients undergoing elective colorectal resection or having stoma formation or reversal at the Royal Adelaide Hospital between August 2018 and May 2020 were recruited into the study. The STIMULAX group received oral Coloxyl® with senna and macrogol, with a sodium phosphate enema in addition for right-sided operations. The control group received standard ERP postoperative care. The primary outcome was GI-2, a validated composite measure defined as the interval from surgery until first passage of stool and tolerance of solid intake for 24 h in the absence of vomiting. Secondary outcomes were the incidence of prolonged postoperative ileus (POI), duration of hospital stay, and postoperative complications. The analysis was performed on an intention-to-treat basis. RESULTS: Of a total of 170 participants, 85 were randomized to each group. Median GI-2 was 1 day shorter in the STIMULAX compared with the control group (median 2 (i.q.r. 1.5-4) versus 3 (2-5.5) days; 95 per cent c.i. -1 to 0 days; P = 0.029). The incidence of prolonged POI was lower in the STIMULAX group (22 versus 38 per cent; relative risk reduction 42 per cent; P = 0.030). There was no difference in duration of hospital day or 30-day postoperative complications (including anastomotic leak) between the STIMULAX and control groups. CONCLUSION: Routine postoperative use of multimodal laxatives after elective colorectal surgery results in earlier recovery of gastrointestinal function and reduces the incidence of prolonged POI. Registration number: ACTRN12618001261202 (www.anzctr.org.au).


Assuntos
Colectomia/efeitos adversos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Trato Gastrointestinal/fisiopatologia , Laxantes/uso terapêutico , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/terapia , Recuperação de Função Fisiológica , Idoso , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/cirurgia , Humanos , Tempo de Internação/tendências , Masculino , Pessoa de Meia-Idade
6.
BJS Open ; 4(4): 577-586, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32459069

RESUMO

BACKGROUND: Recovery of gastrointestinal function is often delayed after major abdominal surgery, leading to postoperative ileus (POI). Enhanced recovery protocols recommend laxatives to reduce the duration of POI, but evidence is unclear. This systematic review aimed to assess the safety and efficacy of laxative use after major abdominal surgery. METHODS: Ovid MEDLINE, Embase, Cochrane Library and PubMed databases were searched from inception to May 2019 to identify eligible RCTs focused on elective open or minimally invasive major abdominal surgery. The primary outcome was time taken to passage of stool. Secondary outcomes were time taken to tolerance of diet, time taken to flatus, length of hospital stay, postoperative complications and readmission to hospital. RESULTS: Five RCTs with a total of 416 patients were included. Laxatives reduced the time to passage of stool (mean difference (MD) -0·83 (95 per cent c.i. -1·39 to -0·26) days; P = 0·004), but there was significant heterogeneity between studies for this outcome measure. There was no difference in time to passage of flatus (MD -0·17 (-0·59 to 0·25) days; P = 0·432), time to tolerance of diet (MD -0·01 (-0·12 to 0·10) days; P = 0·865) or length of hospital stay (MD 0·01(-1·36 to 1·38) days; P = 0·992). There were insufficient data available on postoperative complications for meta-analysis. CONCLUSION: Routine postoperative laxative use after major abdominal surgery may result in earlier passage of stool but does not influence other postoperative recovery parameters. Better data are required for postoperative complications and validated outcome measures.


ANTECEDENTES: El retraso en la recuperación de la función gastrointestinal después de una cirugía abdominal mayor es frecuente y conlleva la aparición de un íleo postoperatorio (postoperative ileus, POI). Los protocolos de rehabilitación multimodal recomiendan la utilización de laxantes para reducir la duración del POI, pero su evidencia no es concluyente. Esta revisión sistemática tuvo como objetivo evaluar la seguridad y la eficacia de la utilización de laxantes tras cirugía abdominal mayor. MÉTODOS: Se realizó una búsqueda de los estudio clínicos aleatorizados (randomised controlled trials, RCTs) centrados en la cirugía abdominal mayor electiva, abierta o mínimamente invasiva, en las bases de datos Ovid MEDLINE, EMBASe, Cochrane Library y PubMed, desde el inicio hasta mayo de 2019. La variable principal fue el tiempo transcurrido hasta la primera deposición. Las variables secundarias fueron el tiempo hasta tolerar la dieta, el tiempo hasta la emisión de ventosidades, la duración de la estancia hospitalaria, las complicaciones postoperatorias y los reingresos hospitalarios. RESULTADOS: Se incluyeron cinco RCTs con un total de 416 pacientes. Los laxantes redujeron el tiempo hasta la primera deposición (diferencia media, mean difference, MD − 0,83 (i.c. del 95% −1,39 a −0,26) días; P = 0,004) pero hubo una heterogeneidad significativa entre los estudios para la medida de este resultado. No hubo diferencias en el tiempo hasta la emisión de ventosidades (DM − 0,17 (−0,59 a 0,25) días; P = 0,432), tiempo hasta la tolerancia de la dieta (DM − 0,01 (−0,12 a 0,10) días; P = 0,865) y la duración de la estancia hospitalaria (DM 0,01 (−1,36 a 1,38) días; P = 0,992). No había datos suficientes de las complicaciones postoperatorias para efectuar un metaanálisis. CONCLUSIÓN: El uso rutinario de laxantes en el postoperatorio de una cirugía abdominal mayor puede acelerar el tránsito de heces, pero no influye en otras variables de la recuperación postoperatoria. Se requieren datos de mayor calidad para evaluar las complicaciones postoperatorias y medidas de resultados validadas.


Assuntos
Abdome/cirurgia , Defecação/efeitos dos fármacos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Laxantes/farmacologia , Gerenciamento de Dados , Humanos , Íleus/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
7.
Schizophr Res ; 215: 300-307, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31744751

RESUMO

Cognitive functioning in schizophrenia is characterized by a generalized impairment in current cognitive ability based on traditional population-based norms. However, these norms assume a normal cognitive trajectory and do not directly account for illness-related declines from expected cognitive potential. Indeed, schizophrenia patients exhibit even greater deviation between their observed and expected cognitive functioning based on expanded norms that leverage premorbid variables resistant to illness-related features. The current study further quantified the extent to which illness-related features account for this deviation from expectation and assessed its relationship to neurophysiologic (mismatch negativity, P3a, theta oscillations), clinical, and psychosocial functioning in schizophrenia patients. Expected cognitive ability (PENN-CNB global cognition) in patients (n = 684) was calculated using healthy comparison subject (n = 660) weighted regression based on premorbid variables resistant to illness-related decline (demographics, single-word reading, parental education). The magnitude of any deviation between current (observed) and regression-predicted (expected) cognitive ability was calculated. Results indicated that 24% (n = 164) of the total patient population exhibited significant (≥-1.96 SD) deviation between observed and expected global cognitive ability. Interestingly, 20% of the total patient population (n = 136) had "normal" range cognitive performance when using traditional population-based norms, but also had significant deviation from expected cognitive ability. The magnitude of this deviation was associated with more severe neurophysiologic abnormalities, longer illness duration, higher levels of negative symptoms, and worse psychosocial functioning. Assessment of cognitive deviation is thus a complementary metric for characterizing the severity of illness-related cognitive declines in patients, while also reflecting the expression and severity of key endophenotypes of schizophrenia.


Assuntos
Aptidão/fisiologia , Disfunção Cognitiva , Potenciais Evocados/fisiologia , Funcionamento Psicossocial , Esquizofrenia , Ritmo Teta/fisiologia , Adulto , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia
8.
Int J Psychophysiol ; 145: 23-29, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30586570

RESUMO

Abnormalities in early auditory information processing (EAIP) contribute to higher-order deficits in cognition and psychosocial functioning in schizophrenia. A passive auditory oddball paradigm is commonly used to evoke event-related potential (ERP) measures of EAIP reflecting auditory sensory registration and deviance detection, including mismatch negativity (MMN) and P3a responses. MMN and P3a have been extensively studied in healthy subjects and neuropsychiatric patient populations and are increasingly used as translational biomarkers in the development of novel therapeutics. Despite widespread use, relatively few studies have examined the constituent oscillatory elements and the extent to which sensory registration and deviance detection represent distinct or intercorrelated processes. This study aimed to determine the factor structure and clinical correlates of these oscillatory measures in schizophrenia patients (n = 706) and healthy comparison subjects (n = 615) who underwent clinical, cognitive, and functional characterization and EEG testing via their participation in the Consortium of Genomics in Schizophrenia (COGS-2) study. Results revealed significant deficits in theta-band (4-7 Hz) evoked power and phase locking in patients. Exploratory factor analyses of both ERP and oscillatory measures revealed two dissociable factors reflecting sensory registration and deviance detection. While each factor shared a significant correlation with social cognition, the deviance detection factor had a unique relationship to multiple cognitive and clinical domains. Results support the continued advancement of functionally relevant oscillatory measures underlying EAIP in the development of precognitive therapeutics.


Assuntos
Encéfalo/fisiopatologia , Cognição/fisiologia , Potenciais Evocados/fisiologia , Esquizofrenia/fisiopatologia , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/fisiologia
9.
Tech Coloproctol ; 21(11): 869-877, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29080956

RESUMO

BACKGROUND: Recently published data support the use of a web-based risk calculator ( www.anastomoticleak.com ) for the prediction of anastomotic leak after colectomy. The aim of this study was to externally validate this calculator on a larger dataset. METHODS: Consecutive adult patients undergoing elective or emergency colectomy for colon cancer at a single institution over a 9-year period were identified using the Binational Colorectal Cancer Audit database. Patients with a rectosigmoid cancer, an R2 resection, or a diverting ostomy were excluded. The primary outcome was anastomotic leak within 90 days as defined by previously published criteria. Area under receiver operating characteristic curve (AUROC) was derived and compared with that of the American College of Surgeons National Surgical Quality Improvement Program® (ACS NSQIP) calculator and the colon leakage score (CLS) calculator for left colectomy. Commercially available artificial intelligence-based analytics software was used to further interrogate the prediction algorithm. RESULTS: A total of 626 patients were identified. Four hundred and fifty-six patients met the inclusion criteria, and 402 had complete data available for all the calculator variables (126 had a left colectomy). Laparoscopic surgery was performed in 39.6% and emergency surgery in 14.7%. The anastomotic leak rate was 7.2%, with 31.0% requiring reoperation. The anastomoticleak.com calculator was significantly predictive of leak and performed better than the ACS NSQIP calculator (AUROC 0.73 vs 0.58) and the CLS calculator (AUROC 0.96 vs 0.80) for left colectomy. Artificial intelligence-predictive analysis supported these findings and identified an improved prediction model. CONCLUSIONS: The anastomotic leak risk calculator is significantly predictive of anastomotic leak after colon cancer resection. Wider investigation of artificial intelligence-based analytics for risk prediction is warranted.


Assuntos
Algoritmos , Fístula Anastomótica/etiologia , Inteligência Artificial , Colectomia/efeitos adversos , Neoplasias do Colo/cirurgia , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/cirurgia , Área Sob a Curva , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Curva ROC , Reoperação , Fatores de Risco
10.
Tech Coloproctol ; 21(1): 35-41, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27995423

RESUMO

BACKGROUND: Anastomotic leak can be a devastating complication, and early prediction is difficult. The aim of this study is to prospectively validate a simple anastomotic leak risk calculator and compare its predictive value with the estimate of the primary operating surgeon. METHODS: Consecutive patients undergoing elective or emergency colon cancer surgery with a primary anastomosis over a 1-year period were prospectively included. A recently published anastomotic leak risk nomogram was converted to an online calculator ( www.anastomoticleak.com ). The calculator-derived risk of anastomotic leak and the risk estimated by the primary operating surgeon were recorded at the completion of surgery. The primary outcome was anastomotic leak within 90 days as defined by previously published criteria. Area under receiver operating characteristic curve analysis (AUROC) was performed for both risk estimates. RESULTS: A total of 105 patients were screened for inclusion during the study period, of whom 83 met the inclusion criteria. The overall anastomotic leak rate was 9.6%. The anastomotic leak calculator was highly predictive of anastomotic leak (AUROC 0.84, P = 0.002), whereas the surgeon estimate was not predictive (AUROC 0.40, P = 0.243). CONCLUSIONS: A simple anastomotic leak risk calculator is significantly better at predicting anastomotic leak than the estimate of the primary surgeon. Further external validation on a larger data set is required.


Assuntos
Fístula Anastomótica/etiologia , Neoplasias do Colo/cirurgia , Cirurgia Colorretal , Internet , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Cirurgia Colorretal/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Medição de Risco/métodos , Fatores de Risco
11.
Br J Cancer ; 112(8): 1384-91, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25867265

RESUMO

BACKGROUND: Biomarkers are needed to improve current diagnosis and surveillance strategies for patients with Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC). Macrophage inhibitory cytokine 1/growth differentiation factor 15 (MIC-1/GDF15) tissue and plasma levels have been shown to predict disease progression in other cancer types and was therefore evaluated in BO/OAC. METHODS: One hundred thirty-eight patients were studied: 45 normal oesophagus (NE), 37 BO, 16 BO with low-grade dysplasia (LGD) and 40 OAC. RESULTS: Median tissue expression of MIC-1/GDF15 mRNA was ⩾25-fold higher in BO and LGD compared to NE (P<0.001); two-fold higher in OAC vs BO (P=0.039); and 47-fold higher in OAC vs NE (P<0.001). Relative MIC-1/GDF15 tissue expression >720 discriminated between the presence of either OAC or LGD vs NE with 94% sensitivity and 71% specificity (ROC AUC 0.86, 95% CI 0.73-0.96; P<0.001). Macrophage inhibitory cytokine 1/growth differentiation factor 15 plasma values were also elevated in patients with OAC vs NE (P<0.001) or BO (P=0.015).High MIC-1/GDF15 plasma levels (⩾1140 pg ml(-1)) were an independent predictor of poor survival for patients with OAC (HR 3.87, 95% CI 1.01-14.75; P=0.047). CONCLUSIONS: Plasma and tissue levels of MIC-1/GDF15 are significantly elevated in patients with BO, LGD and OAC. Plasma MIC-1/GDF15 may have value in diagnosis and monitoring of Barrett's disease.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Fator 15 de Diferenciação de Crescimento/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Fator 15 de Diferenciação de Crescimento/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
12.
J Evol Biol ; 27(10): 2249-57, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25228329

RESUMO

Female choice based on male secondary sexual traits is well documented, although the extent to which this selection can drive an evolutionary divergence in male traits among populations is less clear. Male field crickets Teleogryllus oceanicus attract females using a calling song and once contacted switch to courtship song to persuade them to mate. These crickets also secrete onto their cuticle a cocktail of long-chained fatty acids or cuticular hydrocarbons (CHCs). Females choose among potential mates based on the structure of male acoustic signals and on the composition of male CHC profiles. Here, we utilize two naturally occurring mutations that have arisen independently on two Hawaiian islands and render the male silent to ask whether the evolutionary loss of acoustic signalling can drive an evolutionary divergence in the alternative signalling modality, male CHC profiles. QST -FST comparisons revealed strong patterns of CHC divergence among three populations of crickets on the islands of Hawaii, Oahu and Kauai. Contrasts between wild-type and flatwing males on the islands of Oahu and Kauai indicated that variation in male CHC profiles within populations is associated with the loss of acoustic signalling; flatwing males had a relatively low abundance of long-chained CHCs relative to the short-chained CHCs that females find attractive. Given their dual functions in desiccation resistance and sexual signalling, insect CHCs may be particularly important traits for reproductive isolation and ultimately speciation.


Assuntos
Evolução Biológica , Gryllidae/genética , Hidrocarbonetos/química , Preferência de Acasalamento Animal , Vocalização Animal , Animais , Feminino , Gryllidae/anatomia & histologia , Havaí , Masculino , Mutação , Caracteres Sexuais
14.
Am J Transplant ; 12(3): 763-71, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22070772

RESUMO

Xenotransplantation of genetically modified pig organs offers great potential to address the shortage of human organs for allotransplantation. Rejection in Gal knockout (GTKO) pigs due to elicited non-Gal antibody response required further genetic modifications of donor pigs and better control of the B-cell response to xenoantigens. We report significant prolongation of heterotopic alpha Galactosyl transferase "knock-out" and human CD46 transgenic (GTKO.hCD46Tg) pig cardiac xenografts survival in specific pathogen free baboons. Peritransplant B-cell depletion using 4 weekly doses of anti-CD20 antibody in the context of an established ATG, anti-CD154 and MMF-based immunosuppressive regimen prolonged GTKO.hCD46Tg graft survival for up to 236 days (n = 9, median survival 71 days and mean survival 94 days). B-cell depletion persisted for over 2 months, and elicited anti-non-Gal antibody production remained suppressed for the duration of graft follow-up. This result identifies a critical role for B cells in the mechanisms of elicited anti-non-Gal antibody and delayed xenograft rejection. Model-related morbidity due to variety of causes was seen in these experiments, suggesting that further therapeutic interventions, including candidate genetic modifications of donor pigs, may be necessary to reduce late morbidity in this model to a clinically manageable level.


Assuntos
Linfócitos B/metabolismo , Galactosiltransferases/genética , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Proteína Cofatora de Membrana/genética , Transplante Heterólogo/imunologia , Animais , Animais Geneticamente Modificados , Formação de Anticorpos/imunologia , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Imunossupressores/uso terapêutico , Papio , Taxa de Sobrevida , Suínos
15.
J Evol Biol ; 24(8): 1793-800, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21649764

RESUMO

Animals should decipher information about the genetic make-up of conspecifics in order to enhance the fitness benefits associated with mate choice. Although there is increasing evidence to suggest that animals make genetically informed decisions about their mating partners, we understand relatively little about the sensory mechanisms informing these decisions. Here, we investigate whether cuticular hydrocarbons, chemical compounds found on the cuticle of most terrestrial arthropods, provide a means of discerning genetic similarity during mate choice in the cricket, Teleogryllus oceanicus. We found that individuals preferentially mated with partners who share more dissimilar cuticular hydrocarbon profiles and that similarity in cuticular hydrocarbon profiles between mating pairs correlated with their genetic similarity. Our results provide good evidence that cuticular hydrocarbon profiles offer a means of assessing genetic compatibility in T. oceanicus, enabling individuals to choose their most genetically suitable mate.


Assuntos
Gryllidae/fisiologia , Hidrocarbonetos/química , Preferência de Acasalamento Animal , Comunicação Animal , Animais , Feminino , Gryllidae/genética , Masculino
16.
Paediatr Anaesth ; 20(11): 1017-21, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20964767

RESUMO

OBJECTIVES: To examine the anatomic spread of caudal local anesthetic solution in children aged 1-7 years. AIM: To determine whether incremental increases in the volume of caudal injections of 0.5, 0.75, and 1.0 ml·kg(-1) result in reliable (>90%) and potentially clinically significant increases in the number of vertebral segments reached. BACKGROUND: Caudal block is one of the most frequently performed pediatric regional analgesic techniques. Traditional formulae suggest that changes in the volume of caudal injectate in the range 0.5-1.0 ml·kg(-1) would have clinically useful effects. METHODS: In a single blind design, 45 children aged 1-7 years undergoing caudal block received one of the three predetermined volumes (0.5, 0.75, and 1 ml·kg(-1) ) of local anesthetic solution containing radio-opaque contrast under controlled conditions. Following X-ray examination, the anatomic spread of the block was reported by a radiologist blinded to the volume of solution received. RESULTS: There were 15 children in each group, and they were similar in terms of age, height, and weight. Spread was observed between the 5th lumbar (L5) and 12th thoracic (T12) vertebral levels. A volume of 1 ml·kg(-1) results in a small but significantly greater spread of solution than 0.5 ml·kg(-1) (P < 0.05), but there was no difference between 0.5 and 0.75 ml or between 0.75 and 1.0 ml. No volume reliably reached a level higher than the second lumbar vertebra (L2). CONCLUSIONS: Incrementally increasing the volume of injectate between 0.5 and 1.0 results in a modest increase in the spread of the caudal solution. It is unlikely that volumes of <1 ml will reliably reach a vertebral level that is higher than L2.


Assuntos
Anestesia Caudal , Anestésicos Locais/farmacocinética , Criança , Pré-Escolar , Método Duplo-Cego , Espaço Epidural/anatomia & histologia , Espaço Epidural/diagnóstico por imagem , Espaço Epidural/metabolismo , Feminino , Humanos , Lactente , Masculino , Radiografia , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/metabolismo
17.
Transplant Proc ; 42(6): 2152-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20692431

RESUMO

Evaluation of the function of heterotopic cardiac transplants has traditionally been accomplished by either manual palpation or serial biopsies. Both methods have drawbacks. Palpation can be difficult to differentiate a pulse from the graft versus a transmitted pulse from the native aorta. Serial biopsies, though accurate, require multiple laparotomies, leading to increased morbidity and possibly mortality rates. In this study we used an advanced telemetry system, consisting of an intra-abdominal implant, that was capable of continuously monitoring simultaneously several parameters of the transplanted heart and the status of the recipient. In a large animal model of heterotopic cardiac xenotransplantation (pig donor to baboon recipient), we implanted the device in 12 animals: 8 with and 4 without immunosuppression. We monitored and continuously recorded the left ventricular pressure (both peak-systolic and end-diastolic [LVEDP]), heart rate, and the electrocardiogram pattern of the transplanted heart as well as the temperature of the recipient. The left ventricular pressure proved to be the most valuable parameter to assess graft heart function. In the 4 nonimmunosuppressed cases, grafts were rejected acutely. In these cases, the end-diastolic pressure increased sharply and the heart stopped contracting when the difference between the systolic and the diastolic pressure decreased to <10 mm Hg. The earliest reproducible sign of rejection was an increased LVEDP. Among long-term survivors, the increase in diastolic pressure was gradual, indicating progressive thickening of the myocardium and decreased compliance of the ventricle. Six of 8 immunosuppressed animals died of other complications before rejecting the transplanted heart. The telemetry was also helpful to indicate early onset of fever in the recipients, thus allowing us to intervene early and prevent potentially lethal septic complications. Continuous monitoring of several parameters via telemetry allowed detection of changes associated with rejection as well as other complications at an early stage, allowing prompt intervention, treatment, and possibly reversal of rejection.


Assuntos
Transplante de Coração/efeitos adversos , Telemetria/métodos , Transplante Heterólogo/efeitos adversos , Anastomose Cirúrgica/métodos , Animais , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/imunologia , Imunossupressores/uso terapêutico , Papio , Sobreviventes , Suínos , Doadores de Tecidos
18.
Transplant Proc ; 42(6): 2149-51, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20692430

RESUMO

A modified immunosuppressive regimen, developed at the National Institutes of Health, has been employed in a large animal model of heterotopic cardiac xenotransplantation. Graft survival has been prolonged, but despite this, our recipients have succumbed to various surgical or nonsurgical complications. Herein, we have described different complications and management strategies. The most common complication was hypercoagulability (HC) after transplantation, causing thrombosis of both small and large vasculature, ultimately leading to graft loss. While managing this complication we discovered that there was a delicate balance between HC and consumptive coagulopathy (CC). CC encountered in some recipient baboons was not able to be reversed by stopping anticoagulation and administering multiple blood transfusions. Some complications had iatrogenic components. To monitor the animals, a solid state left ventricular telemetry probe was placed directly into the transplanted heart via the apex. Induction of hypocoagulable states by continuous heparin infusion led to uncontrollable intra-abdominal bleeding in 1 baboon from this apical site. This occurrence necessitated securing the probe more tightly with multiple purse strings and 4-quadrant pledgeted stay sutures. One instance of cardiac rupture originated from a lateral wall infarction site. Earlier studies have shown infections to be uniformly fatal in this transplant model. However, owing to the telemetry placement, infections were identified early by temperature spikes that were treated promptly with antibiotics. We had several cases of wound dehiscence due to recipients disrupting the suture line. These complications were promptly resolved by either re-approximating the wound or finding distractions for the baboon. A few of the most common problems we faced in our earlier experiments were related to the jacket, tether, and infusion pumps. It was difficult to keep the jackets on some baboons and the tether had to be modified several times before we assured long-term success. Infusion catheter replacement resulted in transplant heart venous obstruction and thrombosis from a right common femoral venous line. Homeostatic perturbations such as HC and CC and baboon-induced wound complications comprised most complications. Major bleeding and death due to telemetry implantation and infarct rupture occurred in 2 baboons. Despite the variety of complications, we achieved significant graft prolongation in this model.


Assuntos
Transplante de Coração/efeitos adversos , Complicações Intraoperatórias/classificação , Complicações Pós-Operatórias/classificação , Transplante Heterólogo/efeitos adversos , Transplante Heterotópico/efeitos adversos , Anastomose Cirúrgica/métodos , Animais , Aorta Abdominal/cirurgia , Imunossupressores/uso terapêutico , Papio , Artéria Pulmonar/cirurgia , Suínos , Transplante Heterólogo/imunologia , Transplante Heterotópico/imunologia , Veia Cava Inferior/cirurgia
19.
J Evol Biol ; 21(3): 801-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18355187

RESUMO

The ability of individuals to respond differentially to conspecifics depending on their genetic relatedness is a widespread phenomenon across the animal kingdom. Despite this, little is known about the selection processes that act on the phenotypic variation of traits used during recognition. Here we use a quantitative genetic approach to examine the patterns of genetic variation in cuticular hydrocarbon (CHC) profiles, a pheromonal system used extensively in insect communication. Using gas chromatography, we found family specificity in the CHC profiles of male crickets, Teleogryllus oceanicus. Across CHC peaks, our mean coefficient of additive genetic variation was 10.8%. Multivariate principal component analysis showed that most axes of variation were weighted by CHC peaks with significant additive genetic variation. Our results provide evidence that variation in CHC profiles can reflect genetic relatedness, supporting the widely held belief that this phenotypic trait is used as a mechanism for chemosensory kin recognition.


Assuntos
Gryllidae/genética , Gryllidae/fisiologia , Hidrocarbonetos/metabolismo , Tegumento Comum/fisiologia , Animais , Feminino , Masculino , Feromônios/genética , Feromônios/metabolismo , Especificidade da Espécie
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