Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Nature ; 548(7668): 430-433, 2017 08 24.
Article in English | MEDLINE | ID: mdl-28813416

ABSTRACT

Starburst galaxies at the peak of cosmic star formation are among the most extreme star-forming engines in the Universe, producing stars over about 100 million years (ref. 2). The star-formation rates of these galaxies, which exceed 100 solar masses per year, require large reservoirs of cold molecular gas to be delivered to their cores, despite strong feedback from stars or active galactic nuclei. Consequently, starburst galaxies are ideal for studying the interplay between this feedback and the growth of a galaxy. The methylidyne cation, CH+, is a most useful molecule for such studies because it cannot form in cold gas without suprathermal energy input, so its presence indicates dissipation of mechanical energy or strong ultraviolet irradiation. Here we report the detection of CH+ (J = 1-0) emission and absorption lines in the spectra of six lensed starburst galaxies at redshifts near 2.5. This line has such a high critical density for excitation that it is emitted only in very dense gas, and is absorbed in low-density gas. We find that the CH+ emission lines, which are broader than 1,000 kilometres per second, originate in dense shock waves powered by hot galactic winds. The CH+ absorption lines reveal highly turbulent reservoirs of cool (about 100 kelvin), low-density gas, extending far (more than 10 kiloparsecs) outside the starburst galaxies (which have radii of less than 1 kiloparsec). We show that the galactic winds sustain turbulence in the 10-kiloparsec-scale environments of the galaxies, processing these environments into multiphase, gravitationally bound reservoirs. However, the mass outflow rates are found to be insufficient to balance the star-formation rates. Another mass input is therefore required for these reservoirs, which could be provided by ongoing mergers or cold-stream accretion. Our results suggest that galactic feedback, coupled jointly to turbulence and gravity, extends the starburst phase of a galaxy instead of quenching it.

2.
Am J Transplant ; 16(1): 143-56, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26280997

ABSTRACT

The partial liver's ability to regenerate both as a graft and remnant justifies right lobe (RL) living donor liver transplantation. We studied (using biochemical and radiological parameters) the rate, extent of, and predictors of functional and volumetric recovery of the remnant left liver (RLL) during the first year in 91 consecutive RL donors. Recovery of normal liver function (prothrombin time [PT] ≥70% of normal and total bilirubin [TB] ≤20 µmol/L), liver volumetric recovery, and percentage RLL growth were analyzed. Normal liver function was regained by postoperative day's 7, 30, and 365 in 52%, 86%, and 96% donors, respectively. Similarly, mean liver volumetric recovery was 64%, 71%, and 85%; whereas the percentage liver growth was 85%, 105%, and 146%, respectively. Preoperative PT value (p = 0.01), RLL/total liver volume (TLV) ratio (p = 0.03), middle hepatic vein harvesting (p = 0.02), and postoperative peak TB (p < 0.01) were predictors of early functional recovery, whereas donor age (p = 0.03), RLL/TLV ratio (p = 0.004), and TLV/ body weight ratio (p = 0.02) predicted early volumetric recuperation. One-year post-RL donor hepatectomy, though functional recovery occurs in almost all (96%), donors had incomplete restoration (85%) of preoperative total liver volume. Modifiable predictors of regeneration could help in better and safer donor selection, while continuing to ensure successful recipient outcomes.


Subject(s)
Hepatectomy/methods , Liver Regeneration/physiology , Liver Transplantation/methods , Liver/physiology , Liver/surgery , Living Donors , Tissue and Organ Harvesting/methods , Adult , Female , Humans , Male , Postoperative Period , Prospective Studies , Time Factors
3.
Br J Surg ; 100(6): 808-18, 2013 May.
Article in English | MEDLINE | ID: mdl-23494765

ABSTRACT

BACKGROUND: The oncological benefit of repeat hepatectomy for patients with recurrent colorectal metastases is not yet proven. This study assessed the value of repeat hepatectomy for these patients within current multidisciplinary treatment. METHODS: Consecutive patients treated by repeat hepatectomy for colorectal metastases between January 1990 and January 2010 were included. Patients undergoing two-stage hepatectomy were excluded. Postoperative outcome was analysed and compared with that of patients who had only a single hepatectomy. RESULTS: A total of 1036 patients underwent 1454 hepatectomies for colorectal metastases. Of these, 288 patients had 362 repeat hepatectomies for recurrent metastases. Some 225 patients (78·1 per cent) had two hepatectomies, 52 (18·1 per cent) had three hepatectomies, and 11 patients (3·8 per cent) had a fourth hepatectomy. Postoperative morbidity following repeat hepatectomy was similar to that after initial liver resection (27·1 per cent after first, 34·4 per cent after second and 33·3 per cent after third hepatectomy) (P = 0·069). The postoperative mortality rate was 3·1 per cent after repeat hepatectomy versus 1·6 per cent after first hepatectomy. Three- and 5-year overall survival rates following first hepatectomy in patients who underwent repeat hepatectomy were 76 and 54 per cent respectively, compared with 58 and 45 per cent in patients who had only one hepatectomy (P = 0·003). In multivariable analysis, repeat hepatectomy performed between 2000 and 2010 was the sole independent factor associated with longer overall survival. CONCLUSION: Repeat hepatectomy for recurrent colorectal metastases offers long-term survival in selected patients.


Subject(s)
Colorectal Neoplasms , Hepatectomy/statistics & numerical data , Liver Neoplasms/surgery , Neoplasm Recurrence, Local/surgery , Aged , Analysis of Variance , Female , Hepatectomy/methods , Hepatectomy/mortality , Humans , Liver Neoplasms/mortality , Liver Neoplasms/secondary , Male , Neoplasm Recurrence, Local/mortality , Preoperative Care/methods , Prospective Studies , Reoperation/statistics & numerical data , Survival Analysis , Treatment Outcome , Tumor Burden
4.
J Mater Chem B ; 1(18): 2383-2393, 2013 May 14.
Article in English | MEDLINE | ID: mdl-32261073

ABSTRACT

A layered double hydroxide (LDH) surface was employed as a substrate for growing silver nanoparticles (NPs). An efficient method to produce stable silver/silver chloride nanoparticles supported on the ZnAl-LDH surface was developed. NPs of AgCl were grown on the ZnAl-LDH surface by using AgNO3 as the silver source. The ZnAl-LDH in chloride form acts as a nucleating agent, and depending on the pH of the LDH dispersion, AgClNPs with different dimensions were obtained. In particular AgClNPs with a diameter of 60 nm were formed at pH 5. The AgClNPs supported on LDH sheets were partially reduced by different reducing agents (NaBH4 and formaldehyde) resulting in a Ag/AgCl-LDH nanocomposite. The silver chloride and silver NP dimensions were evaluated by X-ray powder diffraction, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). UV-Vis spectra of the samples upon reduction showed a band centred at 415 nm due to the surface plasmon resonance of silver nanoparticles with a diameter of about 10 nm, in agreement with the TEM analysis. The AgCl-LDH and Ag/AgCl-LDH nanocomposites, subjected to antimicrobial tests, exhibited good antimicrobial activity against both Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus epidermidis and S. aureus) bacteria and yeast (Candida albicans). The nanocomposites were also studied for their ability to release silver by obtaining release curves, under conditions of antibacterial assays. Finally, the nanocomposites antibacterial behavior, as a function of time, was investigated by performing time-kill experiments using S. aureus and Candida albicans.

5.
Am J Transplant ; 11(4): 759-66, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21446978

ABSTRACT

Although domino liver transplantation (LT) is an established procedure, data about the operative risks are limited. This study aimed at evaluating the operative risks of domino LT. Two retrospective analyses were conducted (comparison of familial amyloid polyneuropathy [FAP] liver donors [61 patients] vs. FAP nondonors [39 patients] and FAP liver recipients [61 patients] vs. deceased donor liver recipients [61 patients]). First analysis showed a 60-day mortality of 6.6% for FAP donors and 7.7% for FAP nondonors (p = 1.0). No patient developed primary graft nonfunction. Acute rejection was higher in FAP nondonors compared to FAP donors (38.5% vs. 13.1%). Both groups had similar vascular and biliary complication rates. ICU stay was similar, whereas total hospitalization was longer for FAP nondonors. Both groups had similar 1- and 5-year patient and graft survival rates (83.4% vs. 87.2%, and 79.8% vs. 71.8%, p = 0.7) and (83.3% vs. 87.2%, and 79.1% vs.71.8%, p = 0.7). The second analysis showed a 1.6% mortality for FAP liver recipients vs. 3.2% of the control group (p = 1). Both groups had similar morbidity and technical complication rates (18.0% vs. 13.1%, p = 0.45) and (0.18 vs. 0.15, p = 0.65). The domino procedure does not add any risk to FAP donor or recipient. It increases the organ pool allowing transplantation of marginal recipients who otherwise are denied deceased donor liver transplantation.


Subject(s)
Amyloid Neuropathies, Familial/surgery , Liver Transplantation/methods , Living Donors , Cadaver , Cohort Studies , Female , Humans , Liver Transplantation/mortality , Male , Middle Aged , Retrospective Studies , Survival Rate , Tissue and Organ Harvesting
6.
Am J Transplant ; 11(1): 101-10, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21199351

ABSTRACT

The lack of use of a common grading system in reporting morbidity impedes estimation of the true risk to a right lobe living donor (RLLD). We report outcomes in 91 consecutive RLLD's using the validated 5-tier Clavien grading and a quality of life (QOL) questionnaire. The median follow-up was 79 months. The donors were predominantly female (66%), 22 (24%) received autologous blood transfusions. Fifty-three complications occurred in 43 donors (47% morbidity), 19 (37%) were ≥ Grade III, biliary fistula (14%) was the most common. There was no donor mortality. Two intraoperative complications could not be graded and two disfiguring complications in female donors were graded as minor. Two subgroups (first 46 vs. later 45 donors) were compared to study the presence if any, of a learning curve. The later 45 donors had lesser autologous transfusions, lesser rehospitalization and no reoperation and a reduction in the proportion of ≥ Grade III (major) complications (24% vs. 50%; p = 0.06). In the long term, donors expressed an overall sense of well being, but some sequelae of surgery do restrain their current lifestyle. Our results warn against lackadaisical vigilance once RLLD hepatectomy becomes routine.


Subject(s)
Hepatectomy/adverse effects , Liver Transplantation/adverse effects , Living Donors/statistics & numerical data , Postoperative Complications/epidemiology , Tissue and Organ Harvesting/adverse effects , Adult , Female , France/epidemiology , Hepatectomy/methods , Humans , Male , Middle Aged , Quality of Life
7.
Br J Surg ; 97(2): 240-50, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20087967

ABSTRACT

BACKGROUND: : Portal vein embolization (PVE) increases the resectability of initially unresectable colorectal liver metastases (CLM). This study evaluated long-term survival in patients with CLM who underwent hepatectomy following PVE. METHODS: : In a retrospective analysis patients treated by PVE before major hepatectomy were compared with those who did not have PVE, and with those who had PVE without resection. RESULTS: : Of 364 patients who underwent hepatectomy, 67 had PVE beforehand and 297 did not. Those who had PVE more often had more than three liver metastases (68 versus 40.9 per cent; P < 0.001) that were more frequently bilobar (78 versus 55.2 per cent; P < 0.001), and a higher proportion underwent extended hepatectomy (63 versus 18.1 per cent; P < 0.001). Postoperative morbidity rates were 55 and 41.1 per cent respectively (P = 0.035), and overall 3-year survival rates were 44 and 61.0 per cent (P = 0.001). Thirty-two other patients who were treated by PVE but did not undergo resection all died within 3 years. CONCLUSION: : PVE increased the resectability rate of initially unresectable CLM. Among patients who had PVE, long-term survival was better in those who had resection than in those who did not. PVE is of importance in the multimodal treatment of advanced CLM.


Subject(s)
Colorectal Neoplasms , Embolization, Therapeutic/methods , Liver Neoplasms/secondary , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Embolization, Therapeutic/mortality , Female , Humans , Ligation , Liver Neoplasms/mortality , Liver Neoplasms/surgery , Male , Middle Aged , Portal Vein , Preoperative Care/methods , Survival Analysis , Treatment Outcome
8.
Ann Fr Anesth Reanim ; 25(8): 899-901, 2006 Aug.
Article in French | MEDLINE | ID: mdl-16859879

ABSTRACT

A patient developed an acute severe haemodynamic compromise immediately after a transjugular intrahepatic portosystemic shunt (TIPS) procedure for intractable ascites. Rapid clinical and echographic evaluation disclosed pericardial blood and cardiac tamponade, probably due to right heart perforation from guidewire and catheter manipulation. Needle drainage of pericardial fluid restored the haemodynamic status. A right ventricular perforation was then successfully treated (sternotomy and closure of right ventricle perforation) and the patient survived. Cardiac tamponade should be considered in the differential diagnosis of patients who develop hypotension and haemodynamic impairment during or immediately after TIPS placement.


Subject(s)
Cardiac Tamponade/etiology , Cardiac Tamponade/therapy , Heart Injuries/etiology , Heart Injuries/therapy , Intraoperative Complications/etiology , Portasystemic Shunt, Surgical , Prosthesis Implantation/adverse effects , Anesthesia, General , Drainage , Hemodynamics/physiology , Humans , Male , Middle Aged , Pericardial Effusion
9.
Int J Surg Investig ; 2(1): 81-4, 2000.
Article in English | MEDLINE | ID: mdl-12774342

ABSTRACT

BACKGROUND: Extrahepatic biliary atresia is the most common indication for liver transplantation in children. Coexistent congenital anomalies are common (25%), but the combination of polysplenia syndrome (10%) and absence of portal vein is rare. AIMS: We report a case of successful reduced size liver transplantation on a 13-month-old girl with extrahepatic biliary atresia, polysplenia syndrome and congenital absence of the portal vein. METHODS: Technical and post-operative problems related to absence of the portal vein and polysplenia are described and the literature reviewed. RESULTS: The donor portal vein was successfully anastomosed to the confluence of the superior mesenteric vein and splenic vein. The child is well with good graft function at a follow-up of 20 months. CONCLUSION: Absence of the portal vein and polysplenia syndrome is not a contraindication for liver transplantation although an increased post-operative morbidity may be expected.


Subject(s)
Biliary Atresia/surgery , Liver Transplantation , Portal Vein/abnormalities , Biliary Atresia/complications , Female , Humans , Infant , Spleen/abnormalities
11.
Transpl Int ; 11(4): 281-3, 1998.
Article in English | MEDLINE | ID: mdl-9704392

ABSTRACT

Diaphragmatic paralysis was identified in four children after liver transplantation. All presented with persistent right upper lobe atelectasis, pleural effusion and recurrent respiratory infections and could not be weaned from mechanical ventilatory support. Fluoroscopy and real-time ultrasound confirmed paradoxical right diaphragmatic movements. Diaphragmatic plication was undertaken and enabled rapid and sustained weaning from respiratory support in all four cases. Vascular clamping of the suprahepatic vena cava seems to be the cause. Diaphragmatic plication allows optimal recruitment of the respiratory muscles with a favourable impact on lung mechanics and gas exchange.


Subject(s)
Diaphragm/surgery , Liver Transplantation/adverse effects , Postoperative Complications/surgery , Respiratory Paralysis/surgery , Child, Preschool , Female , Humans , Infant , Male
12.
Transpl Int ; 11(4): 301-4, 1998.
Article in English | MEDLINE | ID: mdl-9704396

ABSTRACT

Bowel perforation is a well-recognized complication following orthotopic liver transplantation. Of 194 paediatric liver transplantations performed in our hospital, 13 patients (6.7%) developed bowel perforation post-transplantation. Contributory factors included previous operation, steroid therapy and viral infection. The incidence was higher in children who underwent transplantation for biliary atresia after a previous Kasai portoenterostomy. Seven patients (53% of this group) reperforated. Diagnosis may be difficult and a high index of suspicion is needed.


Subject(s)
Intestinal Perforation/etiology , Liver Transplantation/adverse effects , Child , Child, Preschool , Humans , Infant
17.
Pediatrie ; 41(5): 401-11, 1986.
Article in French | MEDLINE | ID: mdl-3101037

ABSTRACT

Thirty three patients with Henoch-Schoenlein purpura were studied at various developmental stages of this disease: specially platelet counts and factors XIII and VIII. During the development phases: 40,6% of the patients have a slight but regressive thrombocytosis (greater than 400 G/l); and 75% a reduced factor XIII, well correlated with the severity of the clinical status (level as low as 60% can be considered as a "gravity threshold"), and corrected during the improvement of the disease. This reduced factor XIII is probably linked to the local inflammation in the vessels. Factor VIII studies (specially VIII A: Ag) were normal.


Subject(s)
Factor VIII/analysis , IgA Vasculitis/blood , Thrombocytosis/blood , Adolescent , Blood Coagulation Tests , Child , Child, Preschool , Hemostasis , Humans , IgA Vasculitis/physiopathology , Platelet Count
SELECTION OF CITATIONS
SEARCH DETAIL