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BACKGROUND: Stoma reversal surgery can result in considerable morbidity and even mortality. Feasibility of utilizing single-port laparoscopy through the stoma fenestration have been shown before. Aim of the present observational study is to evaluate multicenter experiences of single-port reversal of left-sided colostomy (SPRLC) throughout Europe and to provide an overview of available literature on this topic. METHODS: All patients undergoing SPRLC in four different teaching hospitals throughout Europe are included. Primary outcome was 30-day postoperative complication rate. Secondary outcomes were postoperative length of stay (LOS), single-port success rate and conversion rates. Appraisal of the available literature in PubMed was performed. RESULTS: Of 156 SPRLC procedures, 98.7% of them were technically successful and 71.8% were without postoperative complications. No postoperative mortality was encountered. Superficial site infection occurred in 14.7%, anastomotic leakage in 3.9% and major complications in 8.3%. Median LOS was 4.0 days (1-69), single-port success rate was 64.7%, 12.8% and 21.2% (33/154) were converted to an open and multiport laparoscopic procedure, respectively. Literature shows equally favorable results in 131 patients divided over 5 cohorts with morbidity ranging from 0 to 30.4% and mortality from 0 to 2.2% and median LOS of 4-8 days. CONCLUSION: This study confirms the safety, feasibility and favorable results of the use of single-port approach in the reversal of left-sided colostomy in different centers in Europe with laparoscopic experienced colorectal surgeons. The available literature on this topic support and show equally favorable results using single-port laparoscopy for left-sided colostomy reversal surgery.
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Laparoscopía , Estomas Quirúrgicos , Anastomosis Quirúrgica/métodos , Colostomía/métodos , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios RetrospectivosRESUMEN
BACKGROUND: Abdominoperineal excision (APE) for rectal cancer is associated with a relatively high risk of positive margins and postoperative morbidity, particularly related to perineal wound healing problems. It is unknown whether the use of a minimally invasive approach for the perineal part of these procedures can improve postoperative outcomes without oncological compromise. The aim of this study was to evaluate the feasibility of minimally invasive transperineal abdominoperineal excision (TpAPE) METHODS: This multicenter retrospective cohort study included all patients having TpAPE for primary low rectal cancer. The primary endpoint was the intraoperative complication rate. Secondary endpoints included major morbidity (Clavien-Dindo ≥ 3), histopathology results, and perineal wound healing. RESULTS: A total of 32 TpAPE procedures were performed in five centers. A bilateral extralevator APE (ELAPE) was performed in 17 patients (53%), a unilateral ELAPE in 7 (22%), and an APE in 8 (25%). Intraoperative complications occurred in five cases (16%) and severe postoperative morbidity in three cases (9%). There were no perioperative deaths. A positive margin (R1) was observed in four patients (13%) and specimen perforation occurred in two (6%). The unilateral extralevator TpAPE group had worse specimen quality and a higher proportion of R1 resections than the bilateral ELAPE or standard APE groups. The rate of uncomplicated perineal wound healing was 53% (n = 17) and three patients (9%) required surgical reintervention. CONCLUSIONS: TpAPE seems to be feasible with acceptable perioperative morbidity and a relatively low rate of perineal wound dehiscence, while histopathological outcomes remain suboptimal. Additional evaluation of the viability of this technique is needed in the form of a prospective trial with standardization of the procedure, indication, audit of outcomes and performed by surgeons with vast experience in transanal total mesorectal excision.
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Procedimientos Quirúrgicos del Sistema Digestivo , Proctectomía , Neoplasias del Recto , Abdomen , Humanos , Perineo/cirugía , Estudios Prospectivos , Neoplasias del Recto/cirugía , Estudios RetrospectivosRESUMEN
BACKGROUND: In colon cancer, appropriate tumour excision and associated lymphadenectomy directly impact recurrence and survival outcomes. Currently, there is no standard for mesenteric lymphadenectomy, with a lymph node yield of 12 acting as a surrogate quality marker. Our goal was to determine the safety and feasibility of indocyanine green (ICG) fluorescence imaging to demonstrate lymphatic drainage in colon cancer in a dose-escalation study. METHODS: A prospective pilot study of colon cancer patients undergoing curative laparoscopic resection was performed. At surgery, peritumoural subserosal ICG injection was done to demonstrate lymphatic drainage of the tumour. A specialized fluorescence system excited the ICG and assessed lymphatics in real time. The primary outcome was the feasibility of ICG fluorescent lymphangiography for lymphatic drainage in colon cancer. Secondary outcomes were the optimal protocol for dose, injection site, and ICG lymphatic mapping timing. RESULTS: Ten consecutive patients were evaluated (six males, mean age 69.5 years). In all, lymphatic channels were seen around the tumour to a varying extent. Eight (80%) had drainage to the sentinel node. In all cases where the lymphatic map was seen, there was no further spread 10 min after injection. In 2 patients (20%), additional lymph nodes located outside of the proposed resection margins were demonstrated. In both cases the resection was extended to include the nodes and in both patients these nodes were positive on histopathology. Factors contributing to reduced lymphatic visualization were inadequate ICG concentrations, excess India ink blocking drainage, and inflammation from tattoo placement. CONCLUSIONS: ICG can be safely injected into the peritumoural subserosal and demonstrate lymphatic drainage in colon cancer. This proof of concept and proposed standards for the procedure can lead to future studies to optimize the application of image-guided precision surgery in colon cancer. Furthermore, this technique may be of value in indicating the need for more extended lymphadenectomy.
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Neoplasias del Colon/patología , Ganglios Linfáticos/diagnóstico por imagen , Linfografía/métodos , Adulto , Anciano , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/cirugía , Estudios de Factibilidad , Femenino , Fluorescencia , Humanos , Verde de Indocianina/administración & dosificación , Laparoscopía/métodos , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Metástasis Linfática , Linfografía/efectos adversos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Proyectos Piloto , Estudios ProspectivosRESUMEN
BACKGROUND AND AIMS: Evidence has shown that a positive resection margin (R1) is a key determinant of subsequent local recurrence and a poor prognostic factor in rectal cancer. The aim of this study was to evaluate the outcomes and prognosticators in patients with R1 resection of rectal cancer. MATERIAL AND METHODS: Retrospective study of all patients operatively managed within our institution between April 2008 and April 2013 for rectal cancer. Baseline demographics and multiple outcome measures recorded. Overall survival (OS), disease-free survival (DFS) and recurrence were the primary outcome measures. RESULTS: Overall, there were 306 primary rectal cancers. Seventy-six percent were grade T3/4 tumours. OS was 30 months. R1 rate was 16 % (48 patients). Thirty-one patients underwent APR and 17 AR. In patients who responded to neoadjuvant chemotherapy (NAC), overall survival was 55 months, with no extramural venous invasion (EMV) seen in this cohort. In non-responders OS was 29 months, with EMV in 48 %. In patients who did not receive NAC, OS was 23 months, with EMV in 74 %. EMV is a strong predictor for poor survival following R1 (p = 0.001). We also found a correlation between number of positive nodes and OS/DFS (p = 0.004). CONCLUSIONS: In this small cohort of patients with R1 positive rectal cancers, response to NAC is the strongest predictor of poor overall and disease-free survival. In patients who respond to NAC, OS and DFS has been shown to be positive, with a reduced rate of EMV.
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Márgenes de Escisión , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Venas/patología , Supervivencia sin Enfermedad , Humanos , Estimación de Kaplan-Meier , Ganglios Linfáticos/patología , Terapia Neoadyuvante , Invasividad Neoplásica , Recurrencia Local de Neoplasia/patología , Neoplasias del Recto/tratamiento farmacológicoRESUMEN
Recent advances in mesenteric science have demonstrated that the mesentery is a continuous structure with a 'watershed' area at the mesenteric apex between the right colon and terminal ileum, where lymphatic flow can proceed either proximally or distally. With this new understanding of the anatomy, functional features are emerging, which can have an impact on surgical management. Fluorescence lymphangiography or lymphoscintigraphy with indocyanine green allows real-time visualization of lymphatic channels, which highlights sentinel lymph nodes and may facilitate identification of the ideal margins for mesenteric lymphadenectomy during bowel resection for colon cancer. By using this novel technology, it is possible to demonstrate a watershed area in the ileocolic region and may facilitate more precise mesenteric dissection. In the present study, we provide proof of concept for the ileocolic watershed area using fluorescence lymphangiography.
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Angiografía con Fluoresceína/métodos , Ganglios Linfáticos/diagnóstico por imagen , Linfografía/métodos , Mesenterio/anatomía & histología , Mesenterio/diagnóstico por imagen , Anciano , Colectomía/métodos , Colon/diagnóstico por imagen , Neoplasias del Colon/cirugía , Colorantes , Femenino , Humanos , Íleon/diagnóstico por imagen , Verde de Indocianina , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/anatomía & histología , Prueba de Estudio ConceptualRESUMEN
INTRODUCTION: It is still an enigma that some patients develop rectal prolapse whilst others with similar risk factors do not. Biomechanical assessment of the skin may provide further insight into the aetiology of this complex condition. Elastin fibres are an abundant and integral part of many extracellular matrices and are especially critical for providing the property of elastic recoil to tissues. The significance of elastin fibres is clearly reflected by the numerous human conditions in which a skin phenotype occurs as a result of elastin fibre abnormalities. METHOD: Between January and June 2013, skin specimens were obtained prospectively during surgery on 20 patients with rectal prolapse and 21 patients without prolapse undergoing surgery for other indications. Expression levels of elastin in the skin were measured by Orcein staining, and Image J. Tensile tests were performed using the Zwick Roell device, with custom ceramic clamps. For statistical analysis, Student's t test was used. RESULTS: Histological analysis of prolapse vs control showed percentage dermal elastin fibres of 9 vs 5.8 % (p = 0.001) in males and 6.5 vs 5.3 % (p = 0.05) in females. Patients with more severe prolapse (external) had a significantly (p = 0.05) higher percentage dermal elastin fibres 6.9 vs 6.1 % than internal prolapse. Young's modulus of patients with prolapse was lower in males (3.3 vs 2.8, p = 0.05) and females (3.1 vs 2.7, p = 0.05). CONCLUSION: Patients with prolapse have a higher concentration of elastin fibres in the skin, and these differences are quantitatively demonstrated through mechanical testing. This suggests that the aetiology may be a result of a dysfunction of elastin fibre assembly.
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Prolapso Rectal/patología , Piel/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Módulo de Elasticidad , Tejido Elástico/patología , Elastina/metabolismo , Femenino , Humanos , Masculino , Prolapso Rectal/fisiopatología , Piel/fisiopatología , Resistencia a la TracciónRESUMEN
AIM: Components of connective tissue other than collagen have been found to be involved in patients with rectal prolapse. The organization of elastic fibres differs between controls and subsets of patients with rectal prolapse, and their importance for maintaining the structural and functional integrity of the pelvic floor has been demonstrated in transgenic mice, with animals which have a null mutation in fibulin-5 (Fbln5(i/i)) developing prolapse. This study aimed to compare fibulin-5 expression in the skin of patients with and without rectal prolapse. METHOD: Between January 2013 and February 2014, skin specimens were obtained during surgery from 20 patients with rectal prolapse and from 21 without prolapse undergoing surgery for other indications. Fibroblasts from the skin were cultured and the level of fibulin-5 expression was determined on cultured fibroblasts, isolated from these specimens by quantitative real-time polymerase chain reaction. Immunohistochemistry was performed on fixed tissue specimens to assess fibulin-5 expression. RESULTS: Fibulin-5 mRNA expression and fibulin-5 staining intensity were significantly lower in young male patients with rectal prolapse compared with age-matched controls [fibulin-5 mean ± SD mRNA relative units, 1.1 ± 0.41 vs 0.53 ± 0.22, P = 0.001; intensity score, median (range), 2 (0-3) vs 1 (0-3), P = 0.05]. There were no significant differences in the expression of fibulin-5 in women with rectal prolapse compared with controls. CONCLUSION: Fibulin-5 may be implicated in the aetiology of rectal prolapse in a subgroup of young male patients.
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Proteínas de la Matriz Extracelular/genética , Regulación de la Expresión Génica , ARN Mensajero/genética , Prolapso Rectal/genética , Piel/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Células Cultivadas , Proteínas de la Matriz Extracelular/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Prolapso Rectal/metabolismo , Piel/patologíaRESUMEN
After taking down the colostomy in a patient who has previously undergone a Hartmann's operation, it is possible to restore bowel continuity using the single-port technique via the colostomy site itself. This study presents our experience of this approach using the glove port and standard laparoscopic instrumentation. Between October 2010 and October 2013, 14 patients [median age 62 years (range 42-83 years); median body mass index 25.2 kg/m(2) (range 22.7-34.9) kg/m(2)] underwent attempted single-port (via colostomy site) reversal of Hartmann's. All but one patient had had a laparotomy for their primary surgery. The glove port was used with a camera and two working ports. Additional remote access was needed in 3 (21 %) patients [1 × 5 mm port (two patients); 2 × 5-mm ports ; 2 × 5-mm ports and Pfannenstiel]. Median operative time was 150 min (range 75-270 min). Mortality was nil. One patient required reoperation and a stoma. Median hospital stay was 5 days (range 2-36 days). Glove port reversal of Hartmann's is technically possible, though challenging if extensive adhesions are present. Outcomes are variable. Further studies will be needed to assess whether this is a safe technique.
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Colon/cirugía , Colostomía , Laparoscopía/métodos , Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Colectomía , Humanos , Laparoscopía/efectos adversos , Laparoscopía/instrumentación , Tiempo de Internación , Persona de Mediana Edad , Tempo Operativo , ReoperaciónRESUMEN
PURPOSE: The purpose of this study was to report and evaluate a laparoscopic surgical technique for the treatment of parastomal hernia (PSH) after ileal conduit urinary diversion aiming to minimize PSH recurrence and perioperative complications. METHODS: We retrospectively evaluated all patients who underwent a PSH (after ileal conduit urinary diversion) repair at Addenbrookes Hospital, Cambridge. As a surgical approach, a laparoscopic repair with mesh was utilized in all cases. Subsequently, we performed a voluntary follow-up of the patients to evaluate long-term recurrence and complication rates. In addition, we conducted a reassessment of the cross-sectional imaging available. RESULTS: Between November 2008 and December 2019, 27 patients underwent hernia repair due to a clinically significant hernia. Out of those patients, one suffered from a post-operative wound infection. In total 23 patients participated in the follow-up with a median follow-up period of 91 months. Follow-up examination revealed two cases of recurrent PSH (8.7% of patients followed up), four patients suffered from minor complications (14.8%). CONCLUSION: Repair of PSH associated with ileal conduit is particularly scarce. Our surgical approach presents the only laparoscopic case series of an effective method for treating a PSH from an ileal conduit with a low complication and recurrence rate.
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Hernia Ventral , Hernia Incisional , Estomas Quirúrgicos , Derivación Urinaria , Hernia Ventral/etiología , Hernia Ventral/cirugía , Herniorrafia/efectos adversos , Humanos , Hernia Incisional/complicaciones , Hernia Incisional/cirugía , Estudios Retrospectivos , Mallas Quirúrgicas/efectos adversos , Estomas Quirúrgicos/efectos adversos , Derivación Urinaria/efectos adversosRESUMEN
AIM: Recto-urethral fistulas are an uncommon, but devastating complication following rectal or urinary tract surgery. Repair is often difficult, and the optimal approach is unclear. We report our recent experience using an endorectal advancement flap. METHOD: A case note review of all patients undergoing repair of recto-urethral fistula in our institution was undertaken. Data on aetiology of the fistula, patient demographics, operative procedure and outcome both clinically and radiologically were extracted. RESULTS: Between 2002 and 2008, six transanal rectal advancement flaps in five patients were carried out. Four had undergone a laparoscopic radical prostatectomy, without any radiotherapy. Two types of fistula (type 1 associated with severe intra-abdominal sepsis and type 2 associated with localized sepsis) were found, with faecal diversion being less likely with the latter. Four (80%) patients underwent successful primary repair, with one patient requiring a second procedure. Postoperative cystography confirmed closure of the fistula in all five patients, and no recurrence has been observed at a mean follow-up time of 11 months. CONCLUSION: Rectal advancement flap is a simple, effective technique for iatrogenic recto-urethral fistula with minimal morbidity.
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Fístula Rectal/cirugía , Colgajos Quirúrgicos , Enfermedades Uretrales/cirugía , Fístula Urinaria/cirugía , Anciano , Cistoscopía/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Prostatectomía/efectos adversos , Fístula Rectal/etiología , Estudios Retrospectivos , Resultado del Tratamiento , Enfermedades Uretrales/etiología , Fístula Urinaria/etiologíaRESUMEN
This study describes the synthesis of a free-standing nanogold membrane by the spontaneous reduction of aqueous chloroaurate ions by the diamine molecule DAEE at a liquid-liquid interface. The free standing nanogold membrane, provides a biocompatible surface for the immobilization of proteins. F-Protease (F-Prot) was then bound to the nanogold membrane via interaction with the gold nanoparticles leading to a new class of biocatalyst. A highlight of the new biocatalyst wherein the enzyme is bound to the nanogold membrane is the ease with which separation from the reaction medium may be achieved by simple filtration. In relation to the free enzyme in solution, the F-Prot in the bioconjugate material exhibited a slightly higher biocatalytic activity and significantly enhanced pH and temperature stability. The F-Prot nanogold membrane bioconjugate material also exhibited excellent biocatalytic activity over ten successive reuse cycles.
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Proteínas Fúngicas/química , Oro/química , Nanopartículas del Metal/química , Nanocompuestos/química , Péptido Hidrolasas/química , Catálisis , Cloro/química , Concentración de Iones de Hidrógeno , Iones , Microscopía Electrónica de Transmisión , Nanopartículas/química , Nanotecnología/métodos , TemperaturaRESUMEN
INTRODUCTION: Indicative numbers for completion of training (CCT) in the UK requires 35 upper Gastrointestinal/Hepatobiliary resections and 110 (50 non HPB trainees) cholecystectomies. We aim to identify whether the training experience in our centre meets the CCT requirements for hepatobiliary surgery and compare training opportunities to those in international fellowships. METHODS: We retrospectively reviewed our hospital's operating theatre database for all patients undergoing a liver or gallbladder resection between January 2008 and July 2015 using corresponding procedural codes and consultant name. The cohort was categorized based on case and primary operating surgeon. The training grade of the surgeon was split into junior registrar (ST3/5), senior registrar (ST6/8) and senior fellow (post-CCT). RESULTS: Over a 7.5 year period we performed 2301 hepatobiliary procedures. The senior fellows and senior registrars performed a median of 42 liver resections (range 15-94) and 77 (range 35-110) cholecystectomies as the primary operator in any given 12 month period. The academic output for the unit was 104 over this period, with a median publication rate of 1.34 papers/trainee in any given 12 months. 15/16 senior fellow/senior registrars went on to secure substantive hepatobiliary consultant posts. CONCLUSIONS: Our centre delivers in excess of the required operative volume and clinical competencies for CCT in Hepatobiliary surgery in a 12 month period and exposure of trainees to operative experience is commensurate to the best performing international fellowships.
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Colecistectomía/educación , Hepatectomía/educación , Evaluación Educacional , Becas , Humanos , Estudios RetrospectivosRESUMEN
INTRODUCTION: The advantages of single port surgery remain controversial. This study was designed to evaluate the safety and feasibility of single incision glove port colon resections using a diathermy hook, reusable ports and standard laparoscopic straight instrumentation. METHODS: Between June 2012 and February 2014, 70 consecutive patients (30 women) underwent a colonic resection using a wound retractor and glove port. Forty patients underwent a right hemicolectomy through the umbilicus and thirty underwent attempted single port resection via an incision in the right rectus sheath (14 high anterior resection, 13 low anterior resection, 3 abdominoperineal resection). RESULTS: Sixty-two procedures (89%) were completed without conversion to open or multiport techniques. Four procedures had to be converted and additional ports were needed in four other patients. The postoperative mortality rate was 0%. Complications occurred in six patients (9%). Two cases were R1 while the remainder were R0 with a median nodal harvest of 20 (range: 9-48). The median length of hospital stay was 5 days (range: 3-25 days) (right hemicolectomy: 5 days (range: 3-12 days), left sided resection: 6 days (range: 4-25 days). At a median follow-up of 14 months, no port site hernias were observed. CONCLUSIONS: Single incision glove port surgery is an appropriate technique for different colorectal cancer resections and has the advantage of being less expensive than surgery with commercial single incision ports.
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Colectomía/métodos , Neoplasias Colorrectales/cirugía , Laparoscopía/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Laparoscopios , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Congenital or true colonic diverticulosis is a rare condition typified by the preservation of the colonic wall architecture within the diverticular outpouching. Cases of multiple jejunal diverticula have been reported as well as cases of solitary giant diverticula of the colon. There have been no reports in the literature of pancolonic congenital diverticulosis.
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A ribulose-1,5-bisphosphate carboxylase/oxygenase-deficient mutant strain (strain I-19) of Rhodospirillum rubrum was capable of growth under photoheterotrophic conditions in the absence of exogenous electron acceptors. These results suggested that alternative means of removing reducing equivalents have been acquired that allow this strain to remove reducing equivalents in the absence of a functional Calvin-Benson-Bassham reductive pentose phosphate pathway. Previously, the proton-reducing activity of the dinitrogenase complex was implicated in helping to maintain redox balance. However, since considerable amounts of CO2 were still fixed in this strain, the complete profile of enzymes involved in alternative CO2 fixation schemes was assessed. A specific and substantial induction of carbon monoxide dehydrogenase (CO dehydrogenase) synthesis was found in the mutant strain; although none of the other CO2 fixation pathways or enzyme activities were altered. These results suggested that CO dehydrogenase contributes to the photoheterotrophic success of strain I-19. Furthermore, the data implicate interacting and complex regulatory processes required to maintain the proper redox balance of this organism and other nonsulfur purple bacteria.
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Aldehído Oxidorreductasas/biosíntesis , Dióxido de Carbono/metabolismo , Complejos Multienzimáticos/biosíntesis , Rhodospirillum rubrum/enzimología , Ribulosa-Bifosfato Carboxilasa/deficiencia , Amoníaco/metabolismo , Medios de Cultivo , Inducción Enzimática , Perfilación de la Expresión Génica , Ácido Glutámico/metabolismo , Luz , Mutación , Oxidación-Reducción , Rhodospirillum rubrum/efectos de la radiación , Ribulosa-Bifosfato Carboxilasa/genéticaRESUMEN
Photosynthesis, biological nitrogen fixation, and carbon dioxide assimilation are three fundamental biological processes catalyzed by photosynthetic bacteria. In the present study, it is shown that mutant strains of the nonsulfur purple photosynthetic bacteria Rhodospirillum rubrum and Rhodobacter sphaeroides, containing a blockage in the primary CO2 assimilatory pathway, derepress the synthesis of components of the nitrogen fixation enzyme complex and abrogate normal control mechanisms. The absence of the Calvin-Benson-Bassham (CBB) reductive pentose phosphate CO2 fixation pathway removes an important route for the dissipation of excess reducing power. Thus the mutant strains develop alternative means to remove these reducing equivalents, resulting in the synthesis of large amounts of nitrogenase even in the presence of ammonia. This response is under the control of a global two-component signal transduction system previously found to regulate photosystem biosynthesis and the transcription of genes required for CO2 fixation through the CBB pathway and alternative routes. In addition, this two-component system directly controls the ability of these bacteria to grow under nitrogen-fixing conditions. These results indicate that there is a molecular link between the CBB and nitrogen fixation process, allowing the cell to overcome powerful control mechanisms to remove excess reducing power generated by photosynthesis and carbon metabolism. Furthermore, these results suggest that the two-component system integrates the expression of genes required for the three processes of photosynthesis, nitrogen fixation, and carbon dioxide fixation.