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101.
Notohara K Burgart LJ Yadav D Chari S Smyrk TC 《The American journal of surgical pathology》2003,27(8):1119-1127
To clarify clinicopathologic features of idiopathic chronic pancreatitis with lymphoplasmacytic infiltration, we carried out a study of 35 cases. There were two histologic groups, which we have designated lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric chronic pancreatitis. Lymphoplasmacytic sclerosing pancreatitis (22 cases) was a fibrosing process with diffuse lymphoplasmacytic infiltrates involving pancreatic lobules and ducts, adipose tissue, blood vessels, and common bile duct. Obliterative phlebitis was found in every case except for one. The histologic features were similar to other idiopathic fibrosclerosing disorders, and one patient also had retroperitoneal fibrosis. Affected patients tended to be elderly men. Idiopathic duct-centric chronic pancreatitis (13 cases) was characterized by inflammatory infiltrates (including neutrophils) that were denser in the lobules than in interlobular fibrotic areas. Neutrophils were also prominent in the ducts, and destruction of the duct epithelium was commonly seen. Patient ages were more broadly distributed than in lymphoplasmacytic sclerosing pancreatitis. Two patients had inflammatory bowel disease. We conclude that idiopathic chronic pancreatitis with lymphoplasmacytic infiltration, sometimes called autoimmune pancreatitis, consists of at least two different processes. One of these, lymphoplasmacytic sclerosing pancreatitis, is a histologically unique lesion and could be a pancreatic manifestation of idiopathic fibrosclerosing disorders. 相似文献
102.
Altered ATP-dependent mitochondrial Ca2+ uptake in cold ischemia is attenuated by ruthenium red 总被引:4,自引:0,他引:4
Belous A Knox C Nicoud IB Pierce J Anderson C Pinson CW Chari RS 《The Journal of surgical research》2003,111(2):284-289
BACKGROUND: Graft dysfunction as a result of preservation injury remains a major clinical problem in liver transplantation. This is related in part to accumulation of mitochondrial calcium (Ca(2+)), which has been linked to activation of proapoptotic factors. We hypothesized that cold ischemia increases mitochondrial Ca(2+) uptake in a concentration dependent fashion and that ruthenium red (RR) will attenuate these changes by inhibiting the mitochondrial Ca(2+) uniporter. METHODS: Rat livers perfused with cold University of Wisconsin (UW) solution (4 degrees C) with or without RR (10 microM) via the portal vein (n = 3 per group) were processed immediately (no ischemia) or after 24 h cold-storage (24 h cold ischemia). Mitochondria were separated by differential centrifugation, and adenosine triphosphate (ATP)-dependent (45)Ca(2+) uptake was determined in the presence of ATP (5 mM), adenosine diphosphate (ADP), or adenosine 5'-beta,gamma-imidotriphosphate (AMP-PNP); variable concentrations of extramitochondrial (45)Ca(2+) were used. All measurements were performed in triplicate. Student's t test with P < 0.05 was taken as significant. RESULTS: Our data demonstrate the following: 1) ATP-dependent (45)Ca(2+) uptake in mitochondria separated from livers following 24 h of cold ischemia in UW alone was higher than in mitochondria isolated from non-ischemic livers; the increased uptake was dependent on the concentration of (45)Ca(2+) in the incubation buffer. 2) There was no difference in ATP-dependent (45)Ca(2+) uptake between nonischemic mitochondria and those separated from livers stored in UW-RR for 24 h. 3) (45)Ca(2+) uptake in mitochondria from livers subjected to 24 h of cold ischemia in UW-RR was significantly lower compared to those from livers stored in UW alone when (45)Ca(2+) concentrations were greater than 1 microM. CONCLUSION: 1) Cold ischemia affects mitochondrial Ca(2+) handling, especially when it is challenged by high extramitochondrial Ca(2+) concentrations. 2) The addition of RR in preservation solution attenuates the effects of cold ischemia on mitochondrial Ca(2+) handling. 3) Inhibition of mitochondrial Ca(2+) uniporter with RR protects mitochondria from Ca(2+) overload at high Ca(2+) concentrations. These findings may offer a potentially effective strategy for prevention of ischemia-reperfusion injury in liver transplantation. 相似文献
103.
BACKGROUND: After more than a decade of growth for laparoscopic cholecystectomy and decline in open cholecystectomy, the impact on the training of resident's in other open biliary operations can be analyzed quantitatively. METHODS: The national operative statistics for residents' operations from 1988 to 2001 (data in the public domain) were analyzed by regression analysis to establish trends and to calculate the rate of change. For laparoscopic biliary operations, the changes in laparoscopic and open operations over time and the number of operations per trainee each year were used to measure the growth of a laparoscopic operation and to predict future trends. A survey of attitude, management algorithm, and self-confidence for coping with unexpected events in laparoscopic cholecystectomy also was conducted for senior residents and recent graduates. RESULTS: In 2001, open cholecystectomy decreased to 28%, open common duct exploration to 27%, sphincteroplasty to 20%, of 1988 (baseline year) levels. Cholecystostomy and choledochoenteric bypass decreased to 70% and 75%, respectively. The decline began before the era of laparoscopic cholecystectomy, but accelerated after its introduction. Many of the recent graduates surveyed in one program indicated a preference for a nonsurgical, mainly endoscopic, approach for all bile duct conditions, but also for the assistance of senior surgeons in the operative management of unexpected events. CONCLUSION: The popularity of noninvasive therapy in biliary surgery significantly reduced the resident's exposure to open biliary surgery, adversely affecting their confidence in the management of unexpected events encountered during laparoscopic operations. Supplemental and remedial education measures must be instituted in training programs. 相似文献
104.
Tandon R Vajpayee RB Gupta V Vajpayee M Satpathy G Dada T 《Indian journal of ophthalmology》2003,51(1):87-88
We describe a case with non-responding polymicrobial spontaneous corneal ulceration in an HIV-positive patient. Acanthamoeba was among the microorganisms isolated. 相似文献
105.
PURPOSE: Reconstruction of the ocular surface in a case of severe bilateral partial limbal stem cell deficiency (LSCD) with extensive symblephara using autologous cultured conjunctival and limbal epithelium. CASE REPORT: A 31-year-old woman presented with severe bilateral ocular surface disease with partial limbal stem cell deficiency, symblephara, lid and facial scarring, with a vision of 20/400 and counting fingers at 1 m in both eyes. Limbal and conjunctival tissue was harvested from the healthy-appearing left eye and used to generate two sheets of composite epithelium consisting of central limbal and peripheral conjunctival cells. The limbal tissues were explanted in the central region while the conjunctival tissues were explanted on the periphery of the deepithelialized human amniotic membrane (HAM) and nurtured using human corneal epithelial cell medium. After successful generation of a monolayer from both tissues had been confirmed, the composite of cultivated limbal and conjunctival epithelium with HAM was transplanted in each eye after excision of fibrous tissue and release of symblephara. One year postoperatively, the patient had a best spectacle-corrected visual acuity of 20/40 in the right eye (preoperative acuity 20/400) and counting fingers at 1 m in the left eye (same as preoperative) with a stable ocular surface. CONCLUSIONS: Autologous cultured epithelial transplantation is as an excellent option in selected patients with bilateral partial LSCD with small area(s) of healthy limbus in either eye and avoids the attendant risk of rejection and cost and potential toxicity of immunosuppression in allogeneic tissue transplantation. This case also highlights the feasibility of generating a composite culture of limbal and conjunctival epithelium using a single amniotic membrane. 相似文献
106.
The management of uveal melanomas always has been a challenge to the clinicians and has evolved from the era of eye-removing surgeries to elimination of the tumor by the body's own immune system through vaccines. Evaluating the outcome of each strategy improves our understanding of the disease process and helps us to improvise on the existing modalities of treatment. Internal resection of choroidal melanomas has been described as one of the treatment modalities for this malignant tumor. Tumor recurrences reported following this surgical procedure have been uncommon. We report a rare case of a 61-year-old Caucasian woman who presented with a 2-month history of progressive, painful proptosis in her right eye. Thirteen years ago she underwent internal resection of an intraocular choroidal melanoma in the same eye and had no evidence of metastatic disease. Magnetic resonance imaging demonstrated a mass occupying the superotemporal portion of the right orbit adjacent to the globe and behind the area of prior internal resection. Biopsy of the lesion and the subsequent A right orbital exenteration confirmed the diagnosis of recurrent malignant melanoma. Twenty-four months following exenteration the patient continues to be free of metastatic disease. Since internal surgical resection was described in 1984, this is the latest known recurrence of a posterior choroidal melanoma. In this review, we highlight the clinical features of this rare case and discuss in brief the rationale of various treatment modalities for choroidal melanoma. 相似文献
107.
Reversed activity of mitochondrial adenine nucleotide translocator in ischemia-reperfusion 总被引:7,自引:0,他引:7
Belous A Knox C Nicoud IB Pierce J Anderson C Pinson CW Chari RS 《Transplantation》2003,75(10):1717-1723
BACKGROUND: Graft dysfunction as a result of preservation injury remains a major clinical problem in liver transplantation. This is related in part to accumulation of mitochondrial calcium. In an attempt to sustain cell and mitochondrial integrity during ischemia, intramitochondrial F(0)F(1) adenosine triphosphate (ATP) synthase reverses its activity and hydrolyzes ATP to maintain the mitochondrial transmembrane potential (mdeltapsi). It is not known how cytoplasmic ATP becomes available for hydrolysis by this enzyme. The authors hypothesized that mitochondrial adenine nucleotide translocator (ANT) reverses its activity during ischemia, making cytoplasmic ATP available for hydrolysis by F(0)F(1) ATP synthase. METHODS: Rat livers were perfused with cold University of Wisconsin solution at 4 degrees C (39.2 degrees F)through the portal vein and processed immediately or after 24 hr of cold storage. Mitochondria were separated by differential centrifugation. ATP-dependent mitochondrial calcium-45 (45Ca)2+ uptake was determined after incubation with ATP (5 mM) or adenosine diphosphate (ADP) (5 mM) with or without 15 microM of bongkrekic acid (BA), an ANT blocker; the nonhydrolyzable analog of ATP (adenosine 5'-beta,gamma-imidotriphosphate [AMP-PNP]) served as the negative control. All measurements were performed in triplicate. Student t test, P<0.05 was taken as significant. RESULTS: Inhibition of ANT by BA prevents mitochondrial Ca2+ accumulation in the presence of ATP and high 45Ca2+ concentrations, and increased extramitochondrial 45Ca2+ stimulated mitochondrial 45Ca2+ uptake in the presence of ATP but not ADP, AMP-PNP, or BA. CONCLUSIONS: These data demonstrate that ANT plays an important role in mitochondrial Ca2+ uptake under ischemic conditions by reversing its activity and allowing transport of extramitochondrial ATP into the matrix for hydrolysis by reversed F(0)F(1) ATP synthase. 相似文献
108.
Niraj G Puri GD Arun D Chakravarty V Aveek J Chari P 《British journal of anaesthesia》2003,91(4):586-589
Background. We assessed appropriate intraoperative use of wholeblood during elective surgery. Methods. This prospective observational audit by a team of anaesthetistsover 3 months in a multi-speciality tertiary care teaching hospitalused strict preset criteria to evaluate the use of blood transfusionduring elective surgery by anaesthetists. The criteria usedto evaluate the rate of appropriate transfusion were haemoglobinless than 8 g dl1, haemoglobin less than 10 g dl1in patients with medical co-morbidities and blood loss greaterthan 20% of blood volume when more than 1000 ml. Results. The overall rate of appropriate use of blood was 40.7%;it was inappropriate in 19.2% of cases (haemoglobin >11 gdl1). The primary trigger was low haemoglobin (measuredintraoperatively or derived from blood loss). Patients in whomhaemoglobin was measured intraoperatively had a significantlyhigher appropriate use of blood (P<0.05). There was a reductionin blood use over the 3-month audit period (P<0.05). Conclusions. Current intraoperative blood use is sub-optimal.Intraoperative haemoglobin estimation is an effective and simplemeasurement to improve appropriate use of blood. The indicationfor transfusion should be recorded in the case notes. Br J Anaesth 2003; 91: 5869 相似文献
109.
Protective effects of ischemic preconditioning on the cold-preserved liver are tyrosine kinase dependent 总被引:5,自引:0,他引:5
Ricciardi R Schaffer BK Kim RD Shah SA Donohue SE Wheeler SM Quarfordt SH Callery MP Meyers WC Chari RS 《Transplantation》2001,72(3):406-412
BACKGROUND: Little data exist regarding the use of ischemic preconditioning before sustained hepatic cold storage. We hypothesized that ischemic preconditioning protects hepatic grafts via a tyrosine kinase-dependent pathway. METHODS: Six porcine livers underwent routine harvest (control). Five other livers underwent 15 min of in situ ischemia followed by 15 min of reflow before harvest (ischemic preconditioning). Another five livers were pretreated with a tyrosine kinase inhibitor (genistein) before preconditioning. Upon reperfusion and after 2 hours of cold storage, graft function, graft circulatory impairment, and markers of cellular damage were analyzed. Tissue cytoplasmic extracts were analyzed for tyrosine phosphorylation with Western blot. Significance was determined with t tests. RESULTS: Ischemic-preconditioned grafts demonstrated enhanced bile production, augmented responses to a bile acid challenge, and elevated O2 consumption (P<0.05) compared to controls. Also, preconditioned grafts demonstrated improved hepatic tissue blood flow and decreased hepatic vascular resistance (P<0.005) compared to controls. Endothelial cell preservation (factor VIII immunostain) was improved in preconditioned graft biopsies compared to controls. With genistein pretreatment, all observed improvements returned to control levels. Analysis of cytoplasmic extracts demonstrated an increase in tyrosine phosphorylation before cold ischemia in preconditioned grafts only, but not in control or genistein-pretreated grafts. CONCLUSIONS: The data indicate that ischemic preconditioning protects the liver from sustained cold ischemia and that tyrosine kinases are involved in preconditioning responses. 相似文献
110.
Perceptual features of consonants were investigated from normally-hearing Ss' confusions of stimuli perceived through one-third-octave bands; 12 Ss were paid to respond to CVs consisting of 17 consonants, each paired with the vowels /i, a, u/ and filtered through one-third-octave bands centered at 0.5, 1, 2, 3.15 and 4 kc/s and one critical band (500 c/s wide) centered at 3.15 kc/s. An earlier cursory analysis of distinctive features in these data (Chari, N.C.A., Herman, G. and Danhauer, J.L. "Perception of one-third octave-band filtered speech." J. Acoust. Soc. Am., 1977, 61, 576-580) showed that while place features were severely affected by the filtering, manner and voicing features were not. The data were submitted in the present study to INDSCAL for a more a-posteriori investigation of the features and their weights by the Ss. Results showed some differences in the features and their weights across the various filter bands, but that they were similar to those found earlier for hearing-impaired Ss having losses corresponding to frequency cut-offs in this study. 相似文献