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1.
Nature ; 605(7908): 139-145, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35444279

RESUMEN

Cellular transformation induces phenotypically diverse populations of tumour-infiltrating T cells1-5, and immune checkpoint blockade therapies preferentially target T cells that recognize cancer cell neoantigens6,7. Yet, how other classes of tumour-infiltrating T cells contribute to cancer immunosurveillance remains elusive. Here, in a survey of T cells in mouse and human malignancies, we identified a population of αß T cell receptor (TCR)-positive FCER1G-expressing innate-like T cells with high cytotoxic potential8 (ILTCKs). These cells were broadly reactive to unmutated self-antigens, arose from distinct thymic progenitors following early encounter with cognate antigens, and were continuously replenished by thymic progenitors during tumour progression. Notably, expansion and effector differentiation of intratumoural ILTCKs depended on interleukin-15 (IL-15) expression in cancer cells, and inducible activation of IL-15 signalling in adoptively transferred ILTCK progenitors suppressed tumour growth. Thus, the antigen receptor self-reactivity, unique ontogeny, and distinct cancer cell-sensing mechanism distinguish ILTCKs from conventional cytotoxic T cells, and define a new class of tumour-elicited immune response.


Asunto(s)
Inmunidad Innata , Interleucina-15 , Neoplasias , Animales , Diferenciación Celular , Ratones , Neoplasias/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T Citotóxicos/metabolismo
2.
Ann Oncol ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39266364

RESUMEN

BACKGROUND: Potential differences in organ preservation between total neoadjuvant therapy (TNT) regimens integrating long-course chemoradiotherapy (LCCRT) and short-course radiotherapy (SCRT) in rectal cancer remain undefined. PATIENTS AND METHODS: This natural experiment arose from a policy change in response to the COVID-19 pandemic during which our institution switched from uniformly treating patients with LCCRT to mandating that all patients be treated with SCRT. Our study includes 323 locally advanced rectal adenocarcinoma patients treated with LCCRT-based or SCRT-based TNT from January 2018 to January 2021. Patients who achieved clinical complete response were offered organ preservation with watch-and-wait (WW) management. The primary outcome was 2-year organ preservation. Additional outcomes included local regrowth, distant recurrence, disease-free survival (DFS), and overall survival (OS). RESULTS: Patient and tumor characteristics were similar between LCCRT (n = 247) and SCRT (n = 76) cohorts. Median follow-up was 31 months. Similar clinical complete response rates were observed following LCCRT and SCRT (44.5% versus 43.4%). Two-year organ preservation was 40% [95% confidence interval (CI) 34% to 46%] and 31% (95% CI 22% to 44%) among all patients treated with LCCRT and SCRT, respectively. In patients managed with WW, LCCRT resulted in higher 2-year organ preservation (89% LCCRT, 95% CI 83% to 95% versus 70% SCRT, 95% CI 55% to 90%; P = 0.005) and lower 2-year local regrowth (19% LCCRT, 95% CI 11% to 26% versus 36% SCRT, 95% CI 16% to 52%; P = 0.072) compared with SCRT. The 2-year distant recurrence (10% versus 6%), DFS (90% versus 90%), and OS (99% versus 100%) were similar between WW patients treated with LCCRT and SCRT, respectively. CONCLUSIONS: While WW eligibility was similar between cohorts, WW patients treated with LCCRT had higher 2-year organ preservation and lower local regrowth than those treated with SCRT, yet similar DFS and OS. These data support induction LCCRT followed by consolidation chemotherapy as the preferred TNT regimen for patients with locally advanced rectal cancer pursuing organ preservation.

3.
Br J Surg ; 108(10): 1251-1258, 2021 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-34240110

RESUMEN

BACKGROUND: The purpose of this study was to investigate the prevalence of ypN+ status according to ypT category in patients with locally advanced rectal cancer treated with chemoradiotherapy and total mesorectal excision, and to assess the impact of ypN+ on disease recurrence and survival by pooled analysis of individual-patient data. METHODS: Individual-patient data from 10 studies of chemoradiotherapy for rectal cancer were included. Pooled rates of ypN+ disease were calculated with 95 per cent confidence interval for each ypT category. Kaplan-Meier and Cox regression analyses were undertaken to assess influence of ypN status on 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: Data on 1898 patients were included in the study. Median follow-up was 50 (range 0-219) months. The pooled rate of ypN+ disease was 7 per cent for ypT0, 12 per cent for ypT1, 17 per cent for ypT2, 40 per cent for ypT3, and 46 per cent for ypT4 tumours. Patients with ypN+ disease had lower 5-year DFS and OS (46.2 and 63.4 per cent respectively) than patients with ypN0 tumours (74.5 and 83.2 per cent) (P < 0.001). Cox regression analyses showed ypN+ status to be an independent predictor of recurrence and death. CONCLUSION: Risk of nodal metastases (ypN+) after chemoradiotherapy increases with advancing ypT category and needs to be considered if an organ-preserving strategy is contemplated.


When patients are diagnosed with rectal cancer and the tumour grows beyond the rectal wall there is a high risk that the tumour has spread to nearby lymph nodes. This study showed that this relationship between tumour invasion depth and lymph node involvement is similar after treatment with (chemo)radiotherapy. Patients who have tumour cells remaining in the lymph nodes after (chemo) radiotherapy have a worse prognosis than patients who do not have cancer cells remaining in the lymph nodes. When an organ-preserving treatment is considered as an alternative therapy, this should be kept in mind during patient counselling.


Asunto(s)
Ganglios Linfáticos/patología , Metástasis Linfática , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Anciano , Anciano de 80 o más Años , Quimioradioterapia Adyuvante , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Proctectomía , Neoplasias del Recto/cirugía , Análisis de Regresión
4.
Br J Surg ; 108(2): 205-213, 2021 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-33711144

RESUMEN

BACKGROUND: In patients with rectal cancer, enlarged lateral lymph nodes (LLNs) result in increased lateral local recurrence (LLR) and lower cancer-specific survival (CSS) rates, which can be improved with (chemo)radiotherapy ((C)RT) and LLN dissection (LLND). This study investigated whether different LLN locations affect oncological outcomes. METHODS: Patients with low cT3-4 rectal cancer without synchronous distant metastases were included in this multicentre retrospective cohort study. All MRI was re-evaluated, with special attention to LLN involvement and response. RESULTS: More advanced cT and cN category were associated with the occurrence of enlarged obturator nodes. Multivariable analyses showed that a node in the internal iliac compartment with a short-axis (SA) size of at least 7 mm on baseline MRI and over 4 mm after (C)RT was predictive of LLR, compared with a post-(C)RT SA of 4 mm or less (hazard ratio (HR) 5.74, 95 per cent c.i. 2.98 to 11.05 vs HR 1.40, 0.19 to 10.20; P < 0.001). Obturator LLNs with a SA larger than 6 mm after (C)RT were associated with a higher 5-year distant metastasis rate and lowered CSS in patients who did not undergo LLND. The survival difference was not present after LLND. Multivariable analyses found that only cT category (HR 2.22, 1.07 to 4.64; P = 0.033) and margin involvement (HR 2.95, 1.18 to 7.37; P = 0.021) independently predicted the development of metastatic disease. CONCLUSION: Internal iliac LLN enlargement is associated with an increased LLR rate, whereas obturator nodes are associated with more advanced disease with increased distant metastasis and reduced CSS rates. LLND improves local control in persistent internal iliac nodes, and might have a role in controlling systemic spread in persistent obturator nodes.Members of the Lateral Node Study Consortium are co-authors of this study and are listed under the heading Collaborators.


Asunto(s)
Metástasis Linfática/patología , Neoplasias del Recto/patología , Anciano , Femenino , Humanos , Escisión del Ganglio Linfático/mortalidad , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/terapia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pelvis , Neoplasias del Recto/mortalidad , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Análisis de Supervivencia
5.
Colorectal Dis ; 21(10): 1140-1150, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31108012

RESUMEN

AIM: Significant recent changes in management of locally advanced rectal cancer (LARC) include preoperative staging, use of extended neoadjuvant therapies and minimally invasive surgery (MIS). This study was aimed at characterizing these changes and associated short-term outcomes. METHOD: We retrospectively analysed treatment and outcome data from patients with T3/4 or N+ LARC ≤ 15 cm from the anal verge who were evaluated at a comprehensive cancer centre in 2009-2015. RESULTS: In total, 798 patients were identified and grouped into five cohorts based on treatment year: 2009-2010, 2011, 2012, 2013 and 2014-2015. Temporal changes included increased reliance on MRI staging, from 57% in 2009-2010 to 98% in 2014-2015 (P < 0.001); increased use of total neoadjuvant therapy, from 17% to 76% (P < 0.001); and increased use of MIS, from 33% to 70% (P < 0.001). Concurrently, median hospital stay decreased (from 7 to 5 days; P < 0.001), as did the rates of Grade III-V complications (from 13% to 7%; P < 0.05), surgical site infections (from 24% to 8%; P < 0.001), anastomotic leak (from 11% to 3%; P < 0.05) and positive circumferential resection margin (from 9% to 4%; P < 0.05). TNM downstaging increased from 62% to 74% (P = 0.002). CONCLUSION: Shifts toward MRI-based staging, total neoadjuvant therapy and MIS occurred between 2009 and 2015. Over the same period, treatment responses improved, and lengths of stay and the incidence of complications decreased.


Asunto(s)
Manejo de la Enfermedad , Terapia Neoadyuvante/tendencias , Grupo de Atención al Paciente/tendencias , Proctectomía/tendencias , Neoplasias del Recto/terapia , Anciano , Femenino , Humanos , Tiempo de Internación/tendencias , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias del Recto/patología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
6.
Tech Coloproctol ; 23(10): 981-985, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31617034

RESUMEN

BACKGROUND: An anastomotic leak is the most dreaded complication after low anterior resection. Adipose tissue grafting may induce healing in a persistent anastomotic defect. The aim of the present study was to report retrospectively reviewed outcomes for a series of patients who were managed with heterotopic grafted adipose tissue to facilitate anastomotic healing. METHODS: Patients with anastomotic leakage after low anterior resection sequentially treated with grafting of adipose tissue were included in the study. All patients had pelvic radiation during treatment and had a diverting ileostomy in situ. The cohort had a persistent defect despite being treated with available modalities such as suture repair, fibrin glue, Endo-Sponge and surgical debridement. The outcomes were reviewed and reported. RESULTS: There were 11 patients (8 males and 3 females) with a median age of 54 years (range 33-72 years). Five patients experienced complete healing of the anastomotic defect with successful reversal of the diverting ileostomy. The anastomotic defect of one other patient in the series appeared to have healed and hence his diverting ileostomy was reversed. However, he presented with a recurrent leak, which ultimately necessitated an abdominoperineal resection. Another patient had a persistent defect after an attempt at adipose tissue grafting and opted to proceed with a takedown of the anastomosis. In the remaining four patients, the outcome after adipose tissue grafting remains unknown, as two patients succumbed to metastatic disease, one was lost to follow-up and the remaining patient developed a recurrence which required pelvic exenteration. Procedural associated morbidity occurred in one patient who developed fat embolism, which was treated expectantly. CONCLUSIONS: Adipose tissue grafting is safe and feasible, though its effectiveness remains uncertain. It may be useful selectively in the management of persistent anastomotic leak after radiation and low anterior resection.


Asunto(s)
Tejido Adiposo/trasplante , Fuga Anastomótica/cirugía , Ileostomía/efectos adversos , Proctectomía/efectos adversos , Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Fuga Anastomótica/etiología , Neoplasias Colorrectales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
7.
Br J Surg ; 105(12): 1680-1687, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29974946

RESUMEN

BACKGROUND: Surgical-site infection (SSI) is associated with significant healthcare costs. To reduce the high rate of SSI among patients undergoing colorectal surgery at a cancer centre, a comprehensive care bundle was implemented and its efficacy tested. METHODS: A pragmatic study involving three phases (baseline, implementation and sustainability) was conducted on patients treated consecutively between 2013 and 2016. The intervention included 13 components related to: bowel preparation; oral and intravenous antibiotic selection and administration; skin preparation, disinfection and hygiene; maintenance of normothermia during surgery; and use of clean instruments for closure. SSI risk was evaluated by means of a preoperative calculator, and effectiveness was assessed using interrupted time-series regression. RESULTS: In a population with a mean BMI of 30 kg/m2 , diabetes mellitus in 17·5 per cent, and smoking history in 49·3 per cent, SSI rates declined from 11·0 to 4·1 per cent following implementation of the intervention bundle (P = 0·001). The greatest reductions in SSI rates occurred in patients at intermediate or high risk of SSI: from 10·3 to 4·7 per cent (P = 0·006) and from 19 to 2 per cent (P < 0·001) respectively. Wound care modifications were very different in the implementation phase (43·2 versus 24·9 per cent baseline), including use of an overlying surface vacuum dressing (17·2 from 1·4 per cent baseline) or leaving wounds partially open (13·2 from 6·7 per cent baseline). As a result, the biggest difference was in wound-related rather than organ-space SSI. The median length of hospital stay decreased from 7 (i.q.r. 5-10) to 6 (5-9) days (P = 0·002). The greatest reduction in hospital stay was seen in patients at high risk of SSI: from 8 to 6 days (P < 0·001). SSI rates remained low (4·5 per cent) in the sustainability phase. CONCLUSION: Meaningful reductions in SSI can be achieved by implementing a multidisciplinary care bundle at a hospital-wide level.


Asunto(s)
Paquetes de Atención al Paciente/normas , Grupo de Atención al Paciente/normas , Infección de la Herida Quirúrgica/prevención & control , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Factores de Riesgo , Resultado del Tratamiento , Técnicas de Cierre de Heridas/normas
8.
Colorectal Dis ; 19(10): 888-894, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28649796

RESUMEN

AIM: Studies have demonstrated a relationship between lymph node (LN) yield and survival after colectomy for cancer. The impact of surgical technique on LN yield has not been well explored. METHOD: This is a retrospective study of right colectomy (RC) for cancer at a single institution from 2012 to 2014. Exclusion criteria were previous colectomy and emergent and palliative operations. All data were collected by chart review. Primary outcomes were LN yield and the LN to length of surgical specimen (LN-LSS) ratio. Multivariable mixed models were created with surgeon and pathologist as random effects. Sensitivity analyses were performed to exclude Stage IV cancers and to analyse groups on an 'as-treated' basis. RESULTS: We identified 181 open (O-RC), 163 laparoscopic (L-RC) and 119 robotic (R-RC) right colectomies. O-RC was more commonly performed in women with metastatic disease. The mean LN yield was 28, 29 and 34 in O-RC, L-RC and R-RC, respectively; the respective mean LN-LSS ratios were 0.83, 0.91 and 1.0. The R-RC approach produced a higher LN yield than the other approaches (P < 0.01), and a higher LN-LSS ratio than O-RC (P < 0.01). These findings were unchanged in sensitivity analyses. CONCLUSION: Robotic right colectomy improves LN yield and the LN-LSS ratio, which may reflect better mesocolic excision. The effect of these findings on survival requires further investigation.


Asunto(s)
Colectomía/métodos , Neoplasias del Colon/cirugía , Laparoscopía/métodos , Escisión del Ganglio Linfático/estadística & datos numéricos , Procedimientos Quirúrgicos Robotizados/métodos , Anciano , Neoplasias del Colon/patología , Femenino , Humanos , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Masculino , Mesocolon/cirugía , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
9.
medRxiv ; 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38712176

RESUMEN

Background: Recent data have demonstrated that in locally advanced rectal cancer (LARC), a total neoadjuvant therapy (TNT) approach improves compliance with chemotherapy and increases rates of tumor response compared to neoadjuvant chemoradiation (CRT) alone. They further indicate that the optimal sequencing of TNT involves consolidation (rather than induction) chemotherapy to optimize complete response rates. Data, largely from retrospective studies, have also shown that patients with clinical complete response (cCR) after neoadjuvant therapy may be managed safely with the watch and wait approach (WW) instead of preemptive total mesorectal resection (TME). However, the optimal consolidation chemotherapy regimen to achieve cCR has not been established, and a randomized clinical trial has not robustly evaluated cCR as a primary endpoint. Collaborating with a multidisciplinary oncology team and patient groups, we designed this NCI-sponsored study of chemotherapy intensification to address these issues and to drive up cCR rates, to provide opportunity for organ preservation, improve quality of life for patients and improve survival outcomes. Methods: In this NCI-sponsored multi-group randomized, seamless phase II/III trial (1:1), up to 760 patients with LARC, T4N0, any T with node positive disease (any T, N+) or T3N0 requiring abdominoperineal resection or coloanal anastomosis and distal margin within 12 cm of anal verge will be enrolled. Stratification factors include tumor stage (T4 vs T1-3), nodal stage (N+ vs N0) and distance from anal verge (0-4; 4-8; 8-12 cm). Patients will be randomized to receive neoadjuvant long course chemoradiation (LCRT) followed by consolidation doublet (mFOLFOX6 or CAPOX) or triplet chemotherapy (mFOLFIRINOX) for 3-4 months. LCRT in both arms involves 4500 cGy in 25 fractions over 5 weeks + 900 cGy boost in 5 fractions with a fluoropyrimidine (capecitabine preferred). Patients will undergo assessment 8-12 (+/- 4) weeks post-TNT completion. The primary endpoint for the phase II portion will compare cCR between treatment arms. A total number of 296 evaluable patients (148 per arm) will provide statistical power of 90.5% to detect an 17% increase in cCR rate, at a one-sided alpha=0.048. The primary endpoint for the phase III portion will compare disease-free survival (DFS) between treatment arms. A total of 285 DFS events will provide 85% power to detect an effect size of hazard ratio 0.70 at a one-sided alpha of 0.025, requiring enrollment of 760 patients (380 per arm). Secondary objectives include time-to event outcomes (overall survival, organ preservation time and time to distant metastasis) and adverse effects. Biospecimens including archival tumor tissue, plasma and buffy coat in EDTA tubes, and serial rectal MRIs will be collected for exploratory correlative research. This study, activated in late 2022, is open across the NCTN and has a current accrual of 312. Support: U10CA180821, U10CA180882, U24 CA196171; https://acknowledgments.alliancefound.org . Discussion: Building off of data from modern day rectal cancer trials and patient input from national advocacy groups, we have designed the current trial studying chemotherapy intensification via a consolidation chemotherapy approach with the intent to enhance cCR and DFS rates, increase organ preservation rates, and improve quality of life for patients with rectal cancer. Trial Registration: Clinicaltrials.gov ID: NCT05610163 ; Support includes U10CA180868 (NRG) and U10CA180888 (SWOG).

10.
Eur Radiol ; 23(12): 3336-44, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23979104

RESUMEN

OBJECTIVE: To explore whether pre-reoperative dynamic contrast-enhanced (DCE)-MRI findings correlate with clinical outcome in patients who undergo surgical treatment for recurrent rectal carcinoma. METHODS: A retrospective study of DCE-MRI in patients with recurrent rectal cancer was performed after obtaining an IRB waiver. We queried our PACS from 1998 to 2012 for examinations performed for recurrent disease. Two radiologists in consensus outlined tumour regions of interest on perfusion images. We explored the correlation between K(trans), Kep, Ve, AUC90 and AUC180 with time to re-recurrence of tumour, overall survival and resection margin status. Univariate Cox PH models were used for survival, while univariate logistic regression was used for margin status. RESULTS: Among 58 patients with pre-treatment DCE-MRI who underwent resection, 36 went directly to surgery and 18 had positive margins. K(trans) (0.55, P = 0.012) and Kep (0.93, P = 0.04) were inversely correlated with positive margins. No significant correlations were noted between K(trans), Kep, Ve, AUC90 and AUC180 and overall survival or time to re-recurrence of tumour. CONCLUSION: K(trans) and Kep were significantly associated with clear resection margins; however overall survival and time to re-recurrence were not predicted. Such information might be helpful for treatment individualisation and deserves further investigation.


Asunto(s)
Aumento de la Imagen/métodos , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/cirugía , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia , Medios de Contraste , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Cuidados Preoperatorios , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Reoperación , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
11.
bioRxiv ; 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37662289

RESUMEN

Metastasis is the principal cause of cancer death, yet we lack an understanding of metastatic cell states, their relationship to primary tumor states, and the mechanisms by which they transition. In a cohort of biospecimen trios from same-patient normal colon, primary and metastatic colorectal cancer, we show that while primary tumors largely adopt LGR5 + intestinal stem-like states, metastases display progressive plasticity. Loss of intestinal cell states is accompanied by reprogramming into a highly conserved fetal progenitor state, followed by non-canonical differentiation into divergent squamous and neuroendocrine-like states, which is exacerbated by chemotherapy and associated with poor patient survival. Using matched patient-derived organoids, we demonstrate that metastatic cancer cells exhibit greater cell-autonomous multilineage differentiation potential in response to microenvironment cues than their intestinal lineage-restricted primary tumor counterparts. We identify PROX1 as a stabilizer of intestinal lineage in the fetal progenitor state, whose downregulation licenses non-canonical reprogramming.

12.
J Cell Biol ; 120(4): 1031-43, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7679388

RESUMEN

Despite the identification and characterization of several distinct ligands for the leukocyte integrin (CD11/CD18) family of adhesion receptors, little is known about the structural regions on these molecules that mediate ligand recognition. In this report, we use alpha subunit chimeras of Mac-1 (CD11b/CD18) and p150,95 (CD11c/CD18), and an extended panel of newly generated and previously characterized mAbs specific to the alpha chain of Mac-1 to map the binding sites for four distinct ligands for Mac-1: iC3b, fibrinogen, ICAM-1, and the as-yet uncharacterized counter-receptor responsible for neutrophil homotypic adhesion. Epitopes of mAbs that blocked ligand binding were mapped with the chimeras and used to localize the ligand recognition sites because the data obtained from functional assays with the Mac-1/p150,95 chimeras were not easily interpreted. Results show that the I domain on the alpha chain of Mac-1 is an important recognition site for all four ligands, and that the NH2-terminal and perhaps divalent cation binding regions but not the COOH-terminal segment may contribute. The recognition sites in the I domain appear overlapping but not identical as individual Mac-1-ligand interactions are distinguished by the discrete patterns of inhibitory mAbs. Additionally, we find that the alpha subunit NH2-terminal region and divalent cation binding region, despite being separated by over 200 amino acids of the I domain, appear structurally apposed because three mAbs require the presence of both of these regions for antigenic reactivity, and chimeras that contain the NH2 terminus of p150,95 require the divalent cation binding region of p150,95 to associate firmly with the beta subunit.


Asunto(s)
Antígenos CD/metabolismo , Antígeno de Macrófago-1/metabolismo , Antígeno de Macrófago-1/ultraestructura , Anticuerpos Monoclonales/inmunología , Sitios de Unión , Antígenos CD18 , Moléculas de Adhesión Celular/metabolismo , Epítopos , Humanos , Integrina alfaXbeta2/inmunología , Integrina alfaXbeta2/metabolismo , Integrina alfaXbeta2/ultraestructura , Molécula 1 de Adhesión Intercelular , Ligandos , Antígeno de Macrófago-1/inmunología , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , Transfección
13.
J Cell Biol ; 111(6 Pt 2): 3129-39, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1980124

RESUMEN

While the leukocyte integrin lymphocyte function-associated antigen (LFA)-1 has been demonstrated to bind intercellular adhesion molecule (ICAM)-1, results with the related Mac-1 molecule have been controversial. We have used multiple cell binding assays, purified Mac-1 and ICAM-1, and cell lines transfected with Mac-1 and ICAM-1 cDNAs to examine the interaction of ICAM-1 with Mac-1. Stimulated human umbilical vein endothelial cells (HUVECs), which express a high surface density of ICAM-1, bind to immunoaffinity-purified Mac-1 adsorbed to artificial substrates in a manner that is inhibited by mAbs to Mac-1 and ICAM-1. Transfected murine L cells or monkey COS cells expressing human ICAM-1 bind to purified Mac-1 in a specific and dose-dependent manner; the attachment to Mac-1 is more temperature sensitive, lower in avidity, and blocked by a different series of ICAM-1 mAbs when compared to LFA-1. In a reciprocal assay, COS cells cotransfected with the alpha and beta chain cDNAs of Mac-1 or LFA-1 attach to immunoaffinity-purified ICAM-1 substrates; this adhesion is blocked by mAbs to ICAM-1 and Mac-1 or LFA-1. Two color fluorescence cell conjugate experiments show that neutrophils stimulated with fMLP bind to HUVEC stimulated with lipopolysaccharide for 24 h in an ICAM-1-, Mac-1-, and LFA-1-dependent fashion. Because cellular and purified Mac-1 interact with cellular and purified ICAM-1, we conclude that ICAM-1 is a counter receptor for Mac-1 and that this receptor pair is responsible, in part, for the adhesion between stimulated neutrophils and stimulated endothelial cells.


Asunto(s)
Antígenos CD/fisiología , Moléculas de Adhesión Celular/fisiología , Antígeno de Macrófago-1/metabolismo , Receptores Inmunológicos , Anticuerpos Monoclonales , Adhesión Celular/fisiología , Cromatografía de Afinidad , Endotelio Vascular/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular , Antígeno-1 Asociado a Función de Linfocito/aislamiento & purificación , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Antígeno de Macrófago-1/aislamiento & purificación , Neutrófilos/metabolismo , Transfección
15.
Hernia ; 20(5): 723-8, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27469592

RESUMEN

PURPOSE: Incisional hernia (IH) is a common complication after colectomy, with impacts on both health care utilization and quality of life. The true incidence of IH after minimally invasive colectomy is not well described. The purpose of this study was to examine IH incidence after minimally invasive right colectomies (RC) and to compare the IH rates after laparoscopic (L-RC) and robotic (R-RC) colectomies. METHODS: This is a retrospective review of patients undergoing minimally invasive RC at a single institution from 2009 to 2014. Only patients undergoing RC for colonic neoplasia were included. Patients with previous colectomy or intraperitoneal chemotherapy were excluded. Three L-RC patients were included for each R-RC patient. The primary outcome was IH rate based on clinical examination or computed tomography (CT). Univariate and multivariate time-to-event analyses were used to assess predictors of IH. RESULTS: 276 patients where included, of which 69 had undergone R-RC and 207 L-RC. Patient and tumor characteristics were similar between the groups, except for higher tumor stage in L-RC patients. Both the median time to diagnosis (9.2 months) and the overall IH rate were similar between the groups (17.4 % for R-RC and 22.2 % for L-RC), as were all other postoperative complications. In multivariable analyses, the only significant predictor of IH was former or current tobacco use (hazard raio 3.0, p = 0.03). CONCLUSIONS: This study suggests that the incidence of IH is high after minimally invasive colectomy and that this rate is equivalent after R-RC and L-RC. Reducing the IH rate represents an important opportunity for improving quality of life and reducing health care utilization after minimally invasive colectomy.


Asunto(s)
Colectomía/efectos adversos , Neoplasias del Colon/cirugía , Hernia Incisional/epidemiología , Laparoscopía/efectos adversos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Anciano , Anciano de 80 o más Años , Colectomía/métodos , Femenino , Humanos , Incidencia , Hernia Incisional/etiología , Masculino , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos
16.
Surgery ; 104(2): 287-91, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3400060

RESUMEN

Recently, serum was shown to contain a factor that increased expression of the complement receptor CR3 on neutrophil membranes. This factor was localized to platelet granules and was released during coagulation. This study was undertaken to identify this factor in platelet granules. Platelet supernatants containing granule contents were incubated with neutrophils, and CR3 expression was determined by flow cytometry. Incubation with platelet supernatants induced more than a twofold increase in the amount of CR3 expressed on the neutrophil membrane (p = 0.05). Anti-platelet-derived growth factor (anti-PDGF) Fab, when preincubated with the platelet supernatants, completely inhibited this CR3-inducing activity. Pure PDGF induced a dose-response increase in CR3, whereas platelet factor 4 had no effect. PDGF was active in concentrations well within the physiologic range. These data indicate that PDGF is responsible for the CR3-inducing activity of platelet supernatants. PDGF may well be an important regulator of neutrophil adherence and phagocytic function in areas of tissue injury.


Asunto(s)
Complemento C3/biosíntesis , Neutrófilos/inmunología , Factor de Crecimiento Derivado de Plaquetas/biosíntesis , Receptores de Complemento/biosíntesis , Membrana Celular , Gránulos Citoplasmáticos/análisis , Relación Dosis-Respuesta a Droga , Humanos , Inmunoglobulina G/inmunología , Técnicas In Vitro , Factor Plaquetario 4/farmacología , Factor de Crecimiento Derivado de Plaquetas/inmunología
17.
Arch Surg ; 123(2): 199-203, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2829790

RESUMEN

The present study investigated the effect of coagulation on neutrophil complement receptors (CRs) 1 and 3, which are specific for the opsonins C3b and C3bi. Incubation of neutrophils in autologous serum, but not in plasma, increased the mean (+/- SD) expression of CR1 (x3.43 +/- 0.93) and CR3 (x3.07 +/- 0.86), in comparison with incubation in buffer. Serum also increased neutrophil superoxide production in response to opsonized zymosan from 0.48 +/- 0.21 to 1.05 +/- 0.25 nmol/10(6) cells/min. Similarly, calcium conversion of platelet-rich plasma (but not platelet-poor plasma) to serum also increased both CR1 and CR3 expression. This finding, as well as the fact that freeze-thawed platelet-rich plasma (but not platelet-poor plasma) increased CR expression, indicated that platelet constituents were the origin of this CR-inducing activity. Other nonplatelet factors formed during coagulation, such as C5a, fibrinogen degradation products, kallikrein, and factor XIIa, were shown not to be responsible for this CR-inducing activity.


Asunto(s)
Factores de Coagulación Sanguínea/inmunología , Plaquetas/inmunología , Activación de Complemento , Complemento C5/inmunología , Neutrófilos/inmunología , Receptores de Complemento/inmunología , Fibrinólisis , Humanos , Activación de Linfocitos , Neutrófilos/metabolismo , Receptores de Complemento 3b , Superóxidos/metabolismo
18.
J Am Coll Surg ; 180(6): 648-53, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7773476

RESUMEN

BACKGROUND: The Roux-en-Y gastrojejunostomy is a popular method in the operative treatment of alkaline reflux gastritis and other postgastrectomy sequelae, but is associated with a high incidence of the so-called "Roux stasis syndrome." The Henley jejunal interposition has been used occasionally, albeit not widely, as an alternative to the Roux-en-Y reconstruction. STUDY DESIGN: Six patients underwent Henley gastrojejunoduodenostomy to treat severe (Visick grade IV) symptoms following Billroth I and II procedures for peptic ulcer disease. All interposed jejunal segments were 40 cm in length and isoperistaltic in orientation. All patients had follow-up examination and telephone interview (mean 4.3 years, range 2.2 to 7.8 years). RESULTS: All patients noted dramatic improvement after remedial surgery in the first year of follow-up. After the first postoperative year, all patients remained virtually symptom-free (Visick grade I and II) with no complaints of gastrojejunal stasis or bile acid reflux. CONCLUSIONS: This experience suggests that the Henley jejunal interposition is our effective method of treating reflux gastritis and is not associated with the poor emptying frequently associated with the Roux-en-Y reconstruction.


Asunto(s)
Reflujo Biliar/cirugía , Gastritis/etiología , Yeyuno/cirugía , Síndromes Posgastrectomía/cirugía , Adulto , Reflujo Biliar/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/cirugía , Complicaciones Posoperatorias
19.
Rev Esp Enferm Dig ; 89(9): 715-7, 1997 Sep.
Artículo en Español | MEDLINE | ID: mdl-9445544

RESUMEN

Gangrene of the stomach is a rare and catastrophic event, usually attributed to local pathologic conditions. Although there are no cases documented in the literature, non-occlusive arterial ischemia is sometimes listed among the causes of necrotizing gastritis. We report a case of necrotizing gastroenteritis associated with a low flow state secondary to an episode of fulminant colitis, fecal peritonitis and septic shock. The patient recovered after staged resection of the involved segments of the gastrointestinal tract.


Asunto(s)
Enterocolitis Seudomembranosa/complicaciones , Gastritis/complicaciones , Enfermedades Inflamatorias del Intestino/complicaciones , Adulto , Terapia Combinada , Procedimientos Quirúrgicos del Sistema Digestivo , Urgencias Médicas , Enterocolitis Seudomembranosa/cirugía , Femenino , Gastritis/cirugía , Humanos , Enfermedades Inflamatorias del Intestino/cirugía , Necrosis , Peritonitis/etiología , Peritonitis/cirugía , Reoperación , Choque Séptico/etiología , Choque Séptico/cirugía
20.
ACS Appl Mater Interfaces ; 6(24): 22506-18, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25419612

RESUMEN

A synthetic procedure to prepare novel materials (surface-mediated fillings) based on robust hierarchical monoliths is reported. The methodology includes the deposition of a (micro- or mesoporous) silica thin film on the support followed by growth of a porous monolithic SiO2 structure. It has been demonstrated that this synthesis is viable for supports of different chemical nature with different inner diameters without shrinkage of the silica filling. The formation mechanism of the surface-mediated fillings is based on a solution/precipitation process and the anchoring of the silica filling to the deposited thin film. The interaction between the two SiO2 structures (monolith and thin film) depends on the porosity of the thin film and yields composite materials with different mechanical stability. By this procedure, capillary microreactors have been prepared and have been proved to be highly active and selective in the total and preferential oxidation of carbon monoxide (TOxCO and PrOxCO).

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