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1.
Opt Lett ; 48(20): 5281-5284, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37831847

RESUMEN

Accurately lateral displacement measurement is essential for a vast of non-contact sensing technologies. Here, we introduce a high-precision lateral displacement measurement method based on differential wavefront sensing (DWS). Compared to the conventional differential power sensing (DPS) method, the DWS method based on phase readout has the potential to achieve a higher resolution. The beam lateral displacement can be obtained by the curvature distribution of the wavefront on the surface of the detector. According to the theoretical model of the DWS method, the sensitivity of the lateral displacement can be greatly improved by increasing the wavefront curvature of the measured laser beam by means of lenses. An optical system for measuring the lateral displacement of the laser beam is built and calibrated by a high-precision hexapod. The experimental results show that the DWS-based lateral displacement measurement achieves a resolution of 40 pm/Hz1/2 (at 1-10 Hz) with a linear range of about 40 µm, which is consistent with the theoretical model. This technique can be applied to high-precision multi-degree-of-freedom interferometers.

2.
Opt Express ; 29(12): 18336-18350, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34154092

RESUMEN

A laser interferometer will be used in the spaceborne gravitational-wave detection missions to measure the inter-satellite optical pathlength variations. The phase readout system of the interferometer needs to be carefully designed and tested to accomplish a shot-noise-limited detection performance under the situation of pico-Watt level received lights. In this work, a scheme based on dual-tone acousto-optic diffraction is presented to verify the performance of the weak-light phase readout system. By optimizing the parameters of the photoreceiver and the local strong-light power, the signal-to-noise ratio of the beat-note signal is enhanced. Thanks to the scheme's common-mode noise rejections for the laser frequency noise, and the optical-path noise, etc., the differential phase noise has achieved a performance of 2×10-4 rad/Hz1/2, which is dominated by the weak-light (∼13 pW) shot noise above the frequencies of 2 mHz.

3.
Rev Sci Instrum ; 92(12): 124501, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34972474

RESUMEN

In the current space gravitational wave (GW) detection, satellites are separated by millions of kilometers. As a result, watts of laser from one satellite is attenuated to the picowatt level at the other end due to the Gaussian beam divergence and the finite aperture of the telescope. Establishing an effective interferometry with such weak-light is a major challenge. The key is to enhance the weak-light while preserving its phase information, which carries the actual GW signal. This can be accomplished by employing an optical phase-locked loop (PLL) to lock the phase of a local oscillator (LO) laser to the weak-light and then sending the power-amplified LO back to the interferometer on the other satellite. Although shot-noise-limited performance of the picowatt level weak-light PLL has been achieved for high frequencies, it remains elusive for frequencies below 0.1 Hz. Here, we propose a three-step experimental scheme to identify the main noise sources of the weak-light PLL, which turn out to be the low-frequency phase measurement noise, the weak-light shot noise, and the laser phase noise. In this paper, the first step experiment result shows that the out-loop phase noise can be suppressed to a level less than 6 × 10-6 rad/√Hz from 6 mHz to 1 Hz by first using the special pilot-tone technique in the PLL to directly reduce the sampling time jitter noise in the digital phasemeter. The out-loop phase noise is mainly limited by the signal amplitude variation and differential time jitter noise of the reference clock.

4.
Rev Sci Instrum ; 89(3): 036106, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29604779

RESUMEN

The sampling jitter noise is one non-negligible noise source of the digital phasemeter used for space gravitational wave detection missions. This note provides a new method for directly reducing the sampling jitter noise of the digital phasemeter, by adding a dedicated signal of which the frequency, amplitude, and initial phase should be pre-set. In contrast to the phase correction using the pilot-tone in the work of Burnett, Gerberding et al., Liang et al., Ales et al., Gerberding et al., and Ware et al. [M.Sc. thesis, Luleå University of Technology, 2010; Classical Quantum Gravity 30, 235029 (2013); Rev. Sci. Instrum. 86, 016106 (2015); Rev. Sci. Instrum. 86, 084502 (2015); Rev. Sci. Instrum. 86, 074501 (2015); and Proceedings of the Earth Science Technology Conference (NASA, USA, 2006)], the new method is intrinsically additive noise suppression. The experiment results validate that the new method directly reduces the sampling jitter noise without data post-processing and provides the same phase measurement noise level (10-6 rad/Hz1/2 at 0.1 Hz) as the pilot-tone correction.

5.
J Clin Exp Hepatol ; 7(1): 33-41, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28348469

RESUMEN

BACKGROUND: The incidence of biliary complications after living donor adult liver transplantation (LDALT) is still high due to the bile duct variation and necessity reconstruction of multiple small bile ducts. The current surgical management of the biliary variants is unsatisfactory. We evaluated the role of a new surgical approach in a complicated hilar bile duct variant (Nakamura type IV and Nakamura type II) under emergent right lobe LDALT for high model for end-stage liver disease score patients. METHODS: The common hepatic duct (CHD) and the left hepatic duct (LHD) of the donor were transected in a right-graft including short common trunks with right posterior and anterior bile ducts, whereas the LHD of the donor was anastomosed to the CHD and the common trunks of a right-graft bile duct and the recipient CHD was end-to-end anastomosed. RESULTS: Ten of 13 grafts (Nakamura types II, III, and IV) had two or more biliary orifices after right graft lobectomy; seven patients had biliary complications (53.8%). Later, the surgical innovation was carried out in five donors with variant bile duct (four Nakamura type IV and one type II), and, consequently, no biliary or other complications were observed in donors and recipients during 47-53 months of follow-up; significant differences (P < 0.05) were found when two stages were compared. CONCLUSION: Our initial experience suggests that, in the urgent condition of LDALT when an alternative live donor was unavailable, a surgical innovation of cutting part of the CHD trunks including variant right hepatic ducts in a complicated donor bile duct variant may facilitate biliary reconstruction and reduce long-term biliary complications.

6.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(10): 1429-1434, 2016 Oct 20.
Artículo en Chino | MEDLINE | ID: mdl-27777211

RESUMEN

OBJECTIVE: To summarize the 23-year experience of laparoscopic biliary surgery in General Hospital of PLA and evaluate the application of laparoscopic surgery in the treatment of biliary diseases. METHODS: We retrospectively analyzed the clinical data of 11 419 consecutive patients with biliary diseases undergoing laparoscopic surgery from April, 1992 and December, 2014. The disease spectrum was compared between patients treated before December 31, 2003 and those treated after the time point. RESULTS: The 11419 patients receiving laparoscopic surgery accounted for 56.3% of the total patients undergoing biliary surgeries during the 23 years, including 4701 male and 6718 female patients with a mean age of 50.9∓13.2 years (6-93 years). Most (80.83%) of the patients received laparoscopic surgery for gallbladder stones, and 12.53% patients had the operation for gallbladder polyps. The laparoscopic operation rate was 84.81% in patients with gallbladder stones and 34.91% in patients with extrahepatic bile duct stones, but remained low in patients with biliary carcinoma. In laparoscopic operations, laparoscopic cholecystectomy was the most frequent (96.18%) followed by operations for extrahepatic bile duct stones, in which primary suture accounted for 1.38%, traditional T tube drainage for 0.90% and laparoscopic transcystic duct exploration for 0.72%. For malignant tumors, laparoscopic technique was used mainly for the purpose of exploration (0.34%). The application of laparoscopic technique in biliary surgery tended to increase after the year 2004, especially for benign gallbladder diseases and extrahepatic bile duct stones (P<0.05). CONCLUSION: Laparoscopic technique in biliary surgery is gradually replacing the traditional open operation and becomes the gold standard for the treatment of benign biliary diseases.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Enfermedades de la Vesícula Biliar/cirugía , Cálculos Biliares/cirugía , Laparoscopía/tendencias , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Conductos Biliares Extrahepáticos , Niño , Colecistectomía Laparoscópica , Drenaje , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
7.
Opt Lett ; 41(5): 914-7, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26974079

RESUMEN

An analytical model of a differential wavefront sensing (DWS) technique based on Gaussian Beam propagation has been derived. Compared with the result of the interference signals detected by quadrant photodiode, which is calculated by using the numerical method, the analytical model has been verified. Both the analytical model and numerical simulation show milli-radians level non-linearity effect of DWS detection. In addition, the beam clipping has strong influence on the non-linearity of DWS. The larger the beam clipping is, the smaller the non-linearity is. However, the beam walking effect hardly has influence on DWS. Thus, it can be ignored in laser interferometer.

8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(2): 195-200, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25936708

RESUMEN

OBJECTIVE: To establish a stable and modified mouse model of brain death (BD) and to share our experiences in BD induction and maintenance. METHODS: Totally 35 C57BL/6 male mice were randomized into BD group (n=25) or sham control group (n=10). BD was induced by inserting a 2F Fogarty catheter connected to a syringe pump after trepanation of the left frontoparietal area and injecting volume at the speed of 6 µl/min until spontaneous respiration ceased. BD was diagnosed by electroencephalogram, apnea testing,as well as testing of brain stem reflexes. Mechanical ventilation was performed by orotracheal intubation. Right carotid artery was intubated by a PE-10 cannula for the continuous monitoring of mean blood pressure (MAP) and heart rate (HR). The right external jugular vein was catheterized for volume resuscitation.The sham control group underwent the same procedure with catheter insertion but without balloon inflation.Livers were removed and fixed in paraffin to evaluate the histological alterations with the light microscopy. RESULTS: Mouse models of BD were successfully established about 20 minutes after balloon inflation, and the mean balloon volume at the time of BD was (105.77 ± 21.57)µl. The MAP and HR rapidly increased on occurrence of BD and the peak value was (128.28 ± 17.16) mmHg and (434.16 ± 55.75) beat/min, respectively, which were significant higher than those in the sham control group at the same time point (P=0.000). During the 4-hour follow-up time, MAP and HR in 72% (18/25) of BD animals remained haemodynamically stable. No animal died due to anesthesia and surgical operation.Hepatic tissues in BD mice showed mild focal ischemic damages (cellular edema, congestion, and inflammatory infiltration), which were slighter and fewer in sham control group. CONCLUSION: The mouse model of BD was successfully established with lower surgical difficulty and can be performed in a standardized, reproducible and successful way.


Asunto(s)
Muerte Encefálica , Modelos Animales de Enfermedad , Presión Intracraneal , Animales , Frecuencia Cardíaca , Masculino , Ratones , Ratones Endogámicos C57BL
9.
Chin Med J (Engl) ; 128(9): 1177-83, 2015 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-25947400

RESUMEN

BACKGROUND: Surgical resection is generally considered the main curative treatment for intrahepatic biliary cystadenocarcinoma (IBCA) or suspected IBCAs, but controversy exists regarding the prognosis for IBCAs. This study aimed to describe the clinicopathological characteristics of IBCA and identify prognostic factors that may influence the survival of patients treated with surgical procedures. METHODS: Thirty-four patients with histologically confirmed IBCA treated between January 2000 and June 2014 were included. The clinical characteristics of patients with IBCA were compared with those of 41 patients with intrahepatic biliary cystadenoma (IBC); factors that significant difference were analyzed for prognosis analysis of IBCA using multivariate/univariate Cox proportional hazards regression models. Survival curves were constructed using the Kaplan-Meier method and compared using the log-rank test. RESULTS: IBCAs had a strong female predominance, and the most common presenting symptoms were abdominal pain or discomfort. Compared with IBCs, IBCAs occurred in older patients, in more male patients, and were associated statistically significant abnormal increase in alanine aminotransferase (P = 0.01) and total bilirubin (P = 0.04). Mural nodules were more frequently seen with IBCAs and may associate with malignancy. It was difficult to differentiate between IBC and IBCA based on laboratory examination and imaging findings. Although complete resection is recommended, enucleation with negative margins also achieved good outcomes. Median overall patient survival was 76.2 months; survival at 1, 3, and 5 years was 88.0%, 68.7%, and 45.8%, respectively. Radical resection and noninvasive tumor type were independent prognostic factors for overall survival. CONCLUSIONS: It remains difficult to distinguish between cystadenomas and cystadenocarcinomas based on laboratory examination and image findings. Complete resection is recommended for curative treatment, and patients should be closely followed postoperatively, particularly those with invasive tumors.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Cistadenocarcinoma/patología , Neoplasias Hepáticas/patología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales
10.
Hepatol Int ; 9(4): 603-11, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25976500

RESUMEN

OBJECTIVE: Cholecystectomy is routinely performed at most transplant centers during living donor liver transplantation (LDLT). This study was performed to evaluate the feasibility of liver graft procurement with donor gallbladder preservation in LDLT. METHODS: Eighty-nine LDLTs (from June 2006 to Dec 2012) were retrospectively analyzed at our hospital. The surgical approach for liver graft procurement with donor gallbladder preservation was assessed, and the anatomy of the cystic artery, the morphology and contractibility of the preserved gallbladder, postoperative symptoms, and vascular and biliary complications were compared among donors with or without gallbladder preservation. RESULTS: Twenty-eight donors (15 right and 13 left-liver grafts) successfully underwent liver graft procurement with gallbladder preservation. Among the 15 right lobectomy donors, for 12 cases (80.0 %) the cystic artery originated from right hepatic artery. From the left hepatic artery and proper hepatic artery accounted for 6.7 % (1/15), respectively. Postoperative symptoms among these 28 donors were slight, although donors with cholecystectomy often complained of fatty food aversion, dyspepsia, and diarrhea during an average follow-up of 58.6 (44-78) months. The morphology and contractibility of the preserved gallbladders were comparable with normal status; the rate of contraction was 53.8 and 76.7 %, respectively, 30 and 60 min after ingestion of a fatty meal. Biliary and vascular complications among donors and recipients, irrespective of gallbladder preservation, were not significantly different. CONCLUSIONS: These data suggest that for donors compliant with anatomical requirements, liver graft procurement with gallbladder preservation for the donor is feasible and safe. The preserved gallbladder was assessed as functioning well and postoperative symptoms as a result of cholecystectomy were significantly reduced during long-term follow-up.


Asunto(s)
Vesícula Biliar/cirugía , Hepatectomía/métodos , Trasplante de Hígado/métodos , Hígado/irrigación sanguínea , Donadores Vivos , Obtención de Tejidos y Órganos/métodos , Adulto , Pancreatocolangiografía por Resonancia Magnética , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Vesícula Biliar/anatomía & histología , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Selección de Paciente , Pronóstico , Estudios Retrospectivos , Factores de Tiempo , Ultrasonografía Doppler , Adulto Joven
11.
Rev Sci Instrum ; 86(1): 016106, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25638133

RESUMEN

This note presents an improved high-resolution frequency measurement system dedicated for the inter-satellite range-rate monitoring that could be used in the future's gravity recovery mission. We set up a simplified common signal test instead of the three frequencies test. The experimental results show that the dominant noises are the sampling time jitter and the thermal drift of electronic components, which can be reduced by using the pilot-tone correction and passive thermal control. The improved noise level is about 10(-8) Hz/Hz(1/2)@0.01Hz, limited by the signal-to-noise ratio of the sampling circuit.

12.
Rev Sci Instrum ; 86(12): 123102, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26724001

RESUMEN

Picometer laser interferometry is an essential tool for ultra-precision measurements in frontier scientific research and advanced manufacturing. In this paper, we present a dual-heterodyne laser interferometer for simultaneously measuring linear and angular displacements with resolutions of picometer and nanoradian, respectively. The phase measurement method is based on cross-correlation analysis and realized by a PXI-bus data acquisition system. By implementing a dual-heterodyne interferometer with a highly symmetric optical configuration, low frequency noises caused by the environmental fluctuations can be suppressed to very low levels via common-mode noise rejection. Experimental results for the dual-heterodyne interferometer configuration presented demonstrate that the noise levels of the linear and angular displacement measurements are approximately 1 pm/Hz(1/2) and 0.5 nrad/Hz(1/2) at 1 Hz.

13.
Chin Med J (Engl) ; 126(5): 884-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23489796

RESUMEN

BACKGROUND: Choledochal cyst excision and biliary enteric reconstruction constitute the best therapy for choledochal cyst. And laparoscopy is currently used to cure this disease now. METHODS: We retrospectively analyzed the clinical data of 34 cases of total laparoscopic choledochal cyst excision between January 2007 and August 2011. All patients underwent in vitro Roux-en-Y hepatoenterostomy. RESULTS: All 34 patients underwent successful total laparoscopic choledochal cyst excision. The operation time was 200 - 360 minutes. The duration of hospital stay was 3 - 7 days. Follow-up observations lasted 1 - 56 months. One patient developed an anastomotic stoma stricture, but no other cases had postoperative complications. No patients died. CONCLUSION: Total laparoscopic choledochal cyst excision is safe and feasible.


Asunto(s)
Quiste del Colédoco/cirugía , Laparoscopía/métodos , Adulto , Femenino , Humanos , Laparoscopía/efectos adversos , Masculino , Complicaciones Posoperatorias , Estudios Retrospectivos , Adulto Joven
14.
Rev Sci Instrum ; 83(9): 095110, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23020422

RESUMEN

Ultra-precision phase measurement is a key technology for state-of-the-art laser interferometry. In this paper we present a fully digital phase measurement method based on cross-correlation analysis, and analyze the measurement errors caused by sampling quantization, intrinsic white noise and non-integral-cycle sampling. The last error source results in a cyclic error that has not been reported ever. We used a high-performance data acquisition system to carry out the cross-correlation-based phase measurement, and obtained a noise level of 1.2 × 10(-6) rad/Hz(1/2)[commercial at]1 Hz. Moreover, the cyclic phase error of about 10(-2) rad/Hz(1/2), caused by non-integral-cycle sampling, had been observed. In order to demonstrate the application of this precision phase measurement method, an ultra-precision heterodyne laser interferometer, consisting of digital phase measurement system and ultra-stable optical bench, was constructed for displacement measurement. The experimental results showed that a measurement resolution of 63 pm had been achieved.

15.
Chin Med J (Engl) ; 125(2): 197-202, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22340545

RESUMEN

BACKGROUND: This retrospective study was undertaken to analyze the outcome of hepatic resection in fifty-two patients with unresectable hepatocellular carcinoma (HCC) between January 2004 and December 2008. METHODS: Among these fifty-two patients, the mean diameter of the tumor was 7.9 cm (4.4 - 15.5 cm, median 8.5 cm) prior to the first transcatheter arterial chemoembolization (TACE). After 1 - 6 times of TACE (median 2), the median tumor diameter was reduced to 4.2 cm (0 - 8.4 cm) prior to resection. The duration between the last TACE treatment and sequential resection varied from one to six months (median 2.7 months). Serum a-fetoprotein (AFP) levels were abnormal in thirty-eight out of the fifty-two patients. In AFP producing HCCs, AFP levels returned to normal (≤ 400 µg/L) in twenty-five out of thirty-eight patients. Hepatic segmentectomy, multiple hepatic segmentectomy or partial hepatic resection were performed in forty-five patients, two underwent extended left hemihepatectomy, and one underwent right posterior branch portal vein thrombectomy. One patient received a right hemihepatectomy and three had left hemihepatectomies. RESULTS: Complete tumor radiological response (CR) occurred in five patients (9.6%). There were three cases of perioperative mortality in the fifty-two patients (5.8%). One patient underwent salvaged orthotopic liver transplantation, and twenty-one patients observed tumor recurrence within two years. The 1-, 3- and 5-year survival rates of the fifty-two patients were 77.0% (n = 40), 55.0% (n = 29), and 52.0% (n = 28), respectively. The median survival time after surgery was 49 months (95% confidence interval 7.5 - 52.7 months). CONCLUSIONS: TACE treatment provides a better chance for HCC resection in patients initially diagnosed with unresectable HCC. Furthermore, liver resection should be performed once the tumor is downstaged to be compatible for successful resection.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Adulto , Anciano , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Femenino , Hepatectomía , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
16.
Chin Med J (Engl) ; 124(18): 2813-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22040485

RESUMEN

BACKGROUND: For patients with end-stage hepatic alveolar echinococcosis (AE), in vivo resection of the involved parts of the liver is usually very difficult, therefore, allogenic liver transplantation is indicated. However, we hypothesize that for selected patents, ex vivo liver resection for thorough elimination of the involved tissues and liver autotransplantation may offer a chance for clinical cure. METHODS: We presented a 24-year-old women with a giant hepatic AE lesion who was treated with hepatectomy, ex vivo resection of the involved tissue and hepatic autotransplantation. The patient had moderate jaundice and advanced hepatic AE lesion which involved segments I, IV, V, VI, VII, VIII and retrohepatic inferior vena cava. The lateral segments (II and III) of the left liver remained normal with over 1000 ml in its volume. No extrahepatic metastases (such as to the lung or brain) could be found. As the first step of treatment, X-ray guided percutaneous transhepatic cholangiodrainage (PTCD) was performed twice for bile drainage in segment III and II separately until her serum total bilirubin decreased gradually from 236 to 88 µmol/L. Total liver resection was then performed, followed by extended right hepatic trisegmentectomy and the entire retrohepatic vena cava was surgically removed en bloc while her hemodynamics parameters were stable. Neither veino-veinous bypass nor temporary intracorporeal cavo-caval or porto-caval shunt was used during the 5.7-hour anhepatic phase. The remained AE-free lateral segments of the left liver were re-implanted in situ. The left hepatic vein was directly anastomosed end-to-end to the suprahepatic inferior vena cava due to the lack of the retrohepatic inferior vena cava with AE total infiltration. Because compensatory retroperitoneal porto-caval collateral circulation developed, we enclosed remained infrahepatic inferior vena cava at renal vein level without any haemodynamics problems. RESULTS: During a 60-day following-up after operation, the patient had a good recovery except for a mildly elevated serum total bilirubin. CONCLUSIONS: As a radical approach, ex vivo liver resection and liver autotransplantation in a case has shown a optimal potential for treatment of the end-stage hepatic AE. Strict compliance with its indications, evaluation of vessels of patients pre-operatively, and precise surgical techniques are the keys to improve the prognosis of patients.


Asunto(s)
Equinococosis Hepática/cirugía , Trasplante de Hígado , Adulto , Albendazol/uso terapéutico , Bilirrubina/sangre , Equinococosis Hepática/sangre , Equinococosis Hepática/diagnóstico por imagen , Femenino , Hepatectomía , Humanos , Radiografía , Adulto Joven
17.
Hepatobiliary Pancreat Dis Int ; 10(4): 369-73, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21813384

RESUMEN

BACKGROUND: Acute hepatic failure (AHF) is a devastating clinical syndrome with a high mortality rate. The outcome of AHF varies with etiology, but liver transplantation (LT) can significantly improve the prognosis and survival rate of such patients. This study aimed to detect the role of LT and artificial liver support systems (ALSS) for AHF patients and to analyze the etiology and outcome of patients with this disease. METHODS: A retrospective analysis was made of 48 consecutive patients with AHF who fulfilled the Kings College Criteria for LT at our center. We analyzed and compared the etiology, outcome, prognosis, and survival rates of patients between the transplantation (LT) group and the non-transplantation (N-LT) group. RESULTS: AHF was due to viral hepatitis in 25 patients (52.1%; hepatitis B virus in 22), drug or toxic reactions in 14 (29.2%; acetaminophen in 6), Wilson disease in 4 (8.3%), unknown reasons in 3 (6.3%), and miscellaneous conditions in 2 (4.2%). In the LT group, 36 patients (7 underwent living donor LT, and 29 cadaveric LT) had an average model for end-stage liver disease score (MELD) of 35.7. Twenty-eight patients survived with good graft function after a follow-up of 27.3+/-4.5 months. During the waiting time, 6 patients were treated with ALSS and 2 of them died during hospitalization. The 30-day, 12-month, and 18-month survival rates were 77.8%, 72.2%, and 66.7%, respectively. In the N-LT group, 12 patients had an average MELD score of 34.5. Four patients were treated with ALSS and all died during hospitalization. The 90-day and 1-year survival rates were only 16.7% and 8.3%, respectively. CONCLUSIONS: Hepatitis is the most prominent cause of AHF at our center. Most patients with AHF, who fulfill the Kings College Criteria for LT, did not survive longer without LT. ALSS did not improve the prognosis of AHF patients, but may extend the waiting time for a donor. Currently, LT is still the most effective way to improve the prognosis of AHF patients.


Asunto(s)
Fallo Hepático Agudo/cirugía , Trasplante de Hígado , Adulto , China , Femenino , Mortalidad Hospitalaria , Humanos , Estimación de Kaplan-Meier , Fallo Hepático Agudo/etiología , Fallo Hepático Agudo/mortalidad , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Hígado Artificial , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
18.
Zhonghua Yi Xue Za Zhi ; 91(14): 950-5, 2011 Apr 12.
Artículo en Chino | MEDLINE | ID: mdl-21609544

RESUMEN

OBJECTIVE: To evaluate the feasibility of sequential liver resection or liver transplantation following downstaging of larger hepatocellular carcinoma (HCC) by transcatheter arterial chemoembolization (TACE). METHODS: A retrospective study was conducted. And a total of 58 patients with unresectable larger HCC (diameter > 5 cm) from June 2006 to March 2010 underwent TACE. According the outcomes of TACE, they received liver transplantation (LT, n = 36) and liver resection (LR, n = 22) respectively. The overall survival (OS) and recurrence-free survival (RFS) rates were calculated by the Kaplan-Meier method. The multivariate analyses for the influencing factors were evaluated by the Cox proportional hazard model. RESULTS: The median follow-up period of 58 cases was 22 months and the median survival time 23.57 ± 1.54 months. The 1-, 2-, 3-year OS and RFS rates after LT was 94%, 84% & 73% and 88%, 75% & 64% respectively. The median recurrence time was 12.3 ± 6.4 months (range: 3 - 23). Twenty-eight patients had adequate downstaging to qualify for LT under the Milan criteria. The 1-, 2-, 3-year OS and RFS of the downstaging group was better than those of the non-downstaging group (OS: 96%, 88%, 75% vs 92%, 48%, 48% P = 0.067; RFS: 95%, 95%, 79% vs 76%, 40%, 40% P = 0.002). The 1-, 2-, 3-years OS and RFS after LR was 100%, 64% & 52% and 72%, 49% & 49% respectively. The median recurrence time was 9.3 ± 4.5 months (range: 3 - 23). The long-term results of LT group following TACE were better than those of LR group (OS, P = 0.178; RFS, P = 0.139). The multivariate analyses showed that only pathologic total tumor diameter > 7 cm (P = 0.002, RR = 6.578), microvascular invasion (P = 0.001, RR = 5.737) and poor differentiation (P = 0.048, RR = 4.335) were significantly correlated with tumor recurrence. CONCLUSION: Sequential liver resection and liver transplantation after downstaging by TACE are feasible for some larger HCCs. And the long-term prognosis is satisfactory.


Asunto(s)
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Adulto , Anciano , Carcinoma Hepatocelular/cirugía , Quimioembolización Terapéutica/métodos , Femenino , Hepatectomía , Humanos , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
19.
Chin Med J (Engl) ; 124(7): 1015-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21542960

RESUMEN

BACKGROUND: Liver transplantation is the most effective treatment for end-stage liver diseases; however, infections after transplantation can seriously affect the patient's health. The aim of this research was to investigate the diagnosis and treatment of fungal infection following liver transplantation. METHODS: Clinical data for 232 liver transplant patients at risk of fungal infection were examined for the presence of fungus in the blood, fluid, sputum, urine and stools of patients and by chest or abdominal CT scans. Patients diagnosed with a fungal infection were treated with Fluconazole or, if this was not effective, Voriconazole or Amphotericin B. Immunosuppressive therapy was also reviewed. RESULTS: Thirty-seven of 232 (15.9%) patients were diagnosed with a fungal infection, which occurred 4 to 34 days post-transplantation. Candida infections were diagnosed in 23 cases (62.2%) and Aspergillus infections in 12 cases (32.4%). Twenty-one cases were effectively treated with Fluconazole, 11 cases with Voriconazole, and two cases with Amphotericin B; however, three cases were not effectively treated with any of the antifungal agents. Overall, treatment was effective in 91.9% of patients. CONCLUSIONS: Fungal infection has a significant influence on survival rate after liver transplantation. Imaging studies, and pathogenic and biopsy examinations can diagnose fungal infections, which can be effectively treated with antifungal agents such as Fluconazole, Voriconazole or Amphotericin B.


Asunto(s)
Trasplante de Hígado/efectos adversos , Micosis/diagnóstico , Adulto , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Femenino , Fluconazol/uso terapéutico , Humanos , Masculino , Micosis/tratamiento farmacológico , Micosis/etiología , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Voriconazol
20.
Rev Sci Instrum ; 82(4): 044501, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21529025

RESUMEN

In this paper, we present the scheme and the preliminary results of an intersatellite laser ranging system that is designed for the Earth's gravity recovery mission proposed in China, called Space Advanced Gravity Measurements (SAGM). The proposed intersatellite distance is about 100 km and the precision of inter-satellite range monitoring is 10 nm/Hz(1/2) at 0.1 Hz. To meet the needs, we designed a transponder-type intersatellite laser ranging system by using a homodyne optical phase locking technique, which is different from the heterodyne optical phase-locked loop used in GRACE follow-on mission. Since an ultrastable oscillator is unnecessary in the homodyne phase-locked loop, the measurement error caused by the frequency instability of the ultrastable oscillator need not be taken into account. In the preliminary study, a heterodyne interferometer with 10-m baseline (measurement arm-length) was built up to demonstrate the validity of the measurement scheme. The measurement results show that a resolution of displacement measurement of about 3.2 nm had been achieved.

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