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M J Phillips

Publications and source records attributed to M J Phillips.

At least 91 records · Page 5Linked to original sources
PubMed1993

Value of CT in determining the resectability of hepatoblastoma before and after chemotherapy.

OBJECTIVE: The purpose of this study was to assess the accuracy of CT for determining surgical resectability of hepatoblastoma before and after chemotherapy. MATERIALS AND METHODS: Preoperative and postoperative CT scans of 15 children with surgically confirmed hepatoblastoma were retrospectively reviewed and correlated with surgical findings and pathologic analysis. RESULTS: Before chemotherapy, 12 of the 15 children had unresectable tumors because of bilobar involvement, metastatic disease, or vascular extension. After chemotherapy, tumor volumes decreased by 20-98%, with increased areas of low attenuation and calcification. Periportal areas of low attenuation (four of nine), abdominal adenopathy (four of four), and lung nodules (four of six) disappeared after chemotherapy. On the basis of CT and clinical findings, all tumors were thought to be resectable. Surgical correlation showed that the extent of hepatic tumor had been overestimated on immediate preoperative CT scans in three children (tumor was staged as bilobar, but only single-lobe resection was required). Correlation between areas of low attenuation in the tumor and necrosis in pathologic specimens was poor. Tumor invasion of periportal lymphatics was seen in one of five children with periportal areas of low attenuation. Postoperatively, five of 13 children had CT abnormalities, three at the resection margins with calcification, low attenuation, or both. Hepatic or abdominal disease has not recurred, and 12 of the 14 children who survived surgery are well. One child who had abnormal findings on preoperative chest CT died of pulmonary metastases. Another in whom chemotherapy was limited because of toxic effects died after tumor recurred in the liver. CONCLUSION: Pretreatment CT scans cannot be used to predict ultimate resectability of hepatic tumors; nor are preoperative scans always accurate for judging exact lobar involvement. Absence of disease as shown on CT scans correlated with absence both at surgery and at follow-up. Postoperative hepatic changes are common and do not necessarily reflect recurrent or residual tumor.

Carcinoma, Hepatocellular↗
PubMed1993

Hepatic morphology and iron quantitation in perinatal hemochromatosis. Comparison with a large perinatal control population, including cases with chronic liver disease.

We compared hepatic morphology, hepatocellular siderosis, extrahepatic parenchymal siderosis, and (by chemical assay of liver and spleen) the amount of elemental iron and copper in 12 cases of perinatal hemochromatosis (PH) with 119 perinatal controls. Controls were subgrouped according to diagnoses based on clinical and autopsy findings; 37 had chronic liver disease, either hepatic fibrosis (17) or cirrhosis (20). Graded semiquantitatively, hepatocellular siderosis varied widely among controls, and some showed more than PH cases. By chemical assay, total hepatic iron in PH cases was not significantly greater than in any control group except the preterm. Therefore, our findings do not support an etiological role for iron in PH. Its distinctive hepatic morphology seems related to onset of liver disease during fetal life, when periportal hepatocytes normally contain hemosiderin (as in 71 of 82 controls without chronic liver disease). Environmental agents (such as hypoxia, virus, drug) that could damage a fetal liver would usually damage other fetal organs as well. They would be unlikely to recur in a subsequent pregnancy and thereby account for PH occurring in siblings. In initiating PH, therefore, putative environmental agents may need to interact with a factor or factors intrinsic to the developing fetal liver.

Chronic Disease↗
PubMed1993

The role of transjugular liver biopsy in fulminant liver failure: relation to other prognostic indicators.

Early and accurate diagnosis and prognosis of patients with fulminant liver failure is of critical importance for optimum management. We investigated the role of transjugular liver biopsy in the management of patients with fulminant liver failure and assessed its value in comparison with the recently proposed King's College criteria. Sixty-one patients with fulminant liver failure, ages 2 to 82 yr, were retrospectively analyzed. The main outcome measures were survival vs. death or progression to orthotopic liver transplantation. Transjugular liver biopsy was successful in 60 of 61 patients, with a mean core tissue length of 2.1 cm. There were eight minor complications, all of which were managed conservatively. Biopsy specimens were evaluated for degree of fibrosis, percentage of hepatocellular necrosis and presence of bile duct proliferation, hepatocellular mitotic figures and binucleate hepatocytes for each of the 54 specimens available for analysis. In 34 of 54 patients (63%), the presumed clinical diagnosis was confirmed by transjugular liver biopsy. In 11 patients the procedure served to clarify clinical uncertainty, whereas in 9 of 54 (16.7%) the diagnosis was altered after transjugular liver biopsy. The percentage of necrosis was the only histological parameter that appeared to have significant discriminatory prognostic value, with only 2 of 19 survivors having greater than 70% necrosis. Twenty-one of these biopsy specimens were reviewed by two pathologists, and their degree of correlation for the various features was assessed. Almost perfect concordance was found between the two pathologists on the percentage of hepatocellular necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaminophen↗
PubMed1993

Role of platelets in hepatic allograft preservation injury in the rat.

Cold preservation of liver allografts injuries hepatic sinusoidal lining cells. This injury is exacerbated on reperfusion, in part because of adhesion of leukocytes. Platelets also adhere to activated endothelial surfaces. In this study we examined the role of platelets in preservation injury. Our specific aim was to determine whether the degree of platelet adhesion on reperfusion of preserved rat livers was related to duration of cold or warm ischemia and whether platelet adhesion resulted in injury to allografts. We also examined the effect of prior activation of platelets on adhesion and injury. Rat livers were preserved at 1 degree C for different time periods in University of Wisconsin solution and then reperfused for 3 hr on the isolated perfused rat liver system with Krebs-Henseleit solution to which unactivated isolated rat platelets were added. Other livers were rewarmed before reperfusion or reperfused with activated platelets. Platelets were lost from the circulation in all studies; the percentage reduction of circulating platelets was dependent on the length of preservation. The initial platelet concentration did not affect the rate of reduction of platelets in the circuit. Rewarming before reperfusion increased platelet adherence, and prior activation also increased adherence. With electron microscopy we determined that platelets adhered in small aggregates to endothelial cells or endothelial cell remnants. Adherent platelets appeared more activated and contained fewer granules than did unperfused platelets. Liver injury as measured by release of transaminases into perfusate was worsened by longer periods of cold preservation and by addition of rewarming to the protocol. The presence of platelets under these circumstances aggravated injury. Prior activation of platelets also increased the extent of injury. These studies show that platelets have an important role in cold preservation-reperfusion injury.

Alanine Transaminase↗
PubMed1992

Monoclonal antiprothrombinase (3D4.3) prevents mortality from murine hepatitis virus (MHV-3) infection.

The induction of monocyte/macrophage procoagulant activity (PCA) has been implicated in the pathogenesis of murine hepatitis virus strain 3 (MHV-3) infection and disease. Previously, we have shown that induction of PCA by MHV-3 correlated with resistance/susceptibility to infection in different mouse strains. In this study, all BALB/cJ mice that were infected with 10(3) plaque-forming units of MHV-3 developed severe liver disease and died within 96-120 h. Examination of the livers of these animals showed marked hepatic necrosis, deposition of fibrin, and cellular expression of PCA by direct immunofluorescence staining in areas of necrosis as well as in hepatic sinusoids. Splenic mononuclear cells recovered from these mice expressed high concentrations of PCA with time after infection. Infusion into mice of a high-titered monoclonal antibody that neutralized PCA (3D4.3) attenuated the development of hepatic necrosis and enhanced survival in a dose-dependent manner. All of the animals receiving 100 micrograms, and 44% and 22% of the animals that received 50 and 25 micrograms per day, respectively, survived for 10 d and made a full recovery. Administration of the antibody resulted in a dose-dependent reduction in fibrin deposition, PCA expression as detected by direct immunofluorescence staining and by a functional assay. In animals treated with high concentrations of antibody, titers of antibody to PCA fell from 87 +/- 15 micrograms/ml to 100 +/- 7 ng/ml during the active phase of the disease, consistent with sequestration due to binding of the immunoglobulin to cells expressing PCA. Surviving animals, when rechallenged with MHV-3, had a 40% mortality, consistent with the known rates of metabolism of immunoglobulin. This further suggested that protection was by a passive mechanism. The results reported here demonstrate that a neutralizing antibody to PCA protects animals from fulminant hepatitis and death associated with MHV-3 infection, and supports the notion that PCA is a potent inflammatory mediator that plays a pivotal role in the pathogenesis of liver injury resulting from MHV-3 infection.

Animals↗
PubMed1992

Assessment of neutrophil chemotaxis by laser and video densitometry.

A laser densitometer and a video densitometer were used to evaluate neutrophil chemotaxis slides which were also assessed by the standard microscopic technique. A linear relationship was observed between cell number per high power field (HPF) and peak height by laser densitometry (r2 = 0.66) or peak area by video densitometry (r2 = 0.81). For wells containing more than 20 cells/HPF the least variability was observed with video densitometry. Quantitative results from neutrophil chemotaxis assays performed in 48-well microchambers can be obtained rapidly and conveniently by the use of commercially available video densitometers.

Chemotaxis, Leukocyte↗
PubMed1992

Carotid body tumor.

To better define the management and behavior of carotid body tumors, a 34-year surgical experience with 33 tumors in 30 patients was reviewed. There were 20 women and 10 men with an age range of 20 to 78 years. All but one presented with a neck mass. Arteriography was performed on 21 patients and was diagnostic in every case. There was no surgical mortality. Complications occurred in eight patients (27%), and one long-term neurologic deficit occurred. Three of 33 tumors were malignant, and aggressive resection of all approachable disease with radiotherapy for unresectable metastases led to prolonged survival in each case. Carotid body tumors present with neck mass. Arteriography is diagnostic and surgery is indicated. Even for malignant tumors and metastases, aggressive resection and radiotherapy are indicated.

Adult↗
PubMed1992

Membrane region of surface IgM is not sufficient for transducing growth inhibitory signals in an immature B cell line WEHI-231.

The murine B lymphoma line WEHI-231 is representative of immature B cells. Like normal immature B cells, WEHI-231 is susceptible to growth arrest following cross-linking of surface IgM (sIgM). Previously, we have shown using a WEHI-231 immunoglobulin (Ig) delta-transfectant that sIgD cross-linking failed to initiate growth arrest, in contrast to sIgM. In this report, we extend our research to investigate the structural requirement of Ig mu chain for regulating growth inhibition. Recombinant, chimeric Ig molecules delta/mu m and mu/delta m consisting of exons encoding extracellular delta and mu domains and membrane regions of different isotypes were constructed and introduced into WEHI-231 cells. A similar approach was used for sIgG2b-expressing transfectants. Our findings indicate that the mu m region is not sufficient for regulation of growth inhibition in WEHI-231 cells and suggest that additional extracellular region(s) of mu chain may be required for this response.

Animals↗
PubMed1992

Transjugular liver biopsy in children.

Transjugular liver biopsy is widely used in adult patients with liver disease when transthoracic needle liver biopsy is contraindicated by severe coagulopathy or ascites. It has not been used extensively in children. We report our experience with 30 consecutive transjugular liver biopsy procedures performed in 27 young patients at the Hospital for Sick Children in Toronto. Patient weights ranged from 14 to 91 kg (median = 42 kg); most patients had not yet attained adult size. A 9F catheter was used except in very small children, for whom we developed a 7F biopsy needle catheter. Most procedures were done with patients under general anesthesia. Specimens were obtained in all patients, and the procedure was tolerated well. A major complication occurred only once: perforation of the inferior vena cava, which was later repaired at liver transplantation. Minor complications included subcapsular extravasation of contrast agent in five patients and a small intrahepatic hematoma in one. Results of transjugular liver biopsy changed the diagnosis in 30% of patients and added valuable information about the disease process in most patients. Transjugular liver biopsy was an important component of emergency assessment for liver transplantation. Our results indicate that transjugular liver biopsy can be performed safely in children with liver disease if a skilled interventional radiologist and a well-equipped angiography suite are available. Histological studies in these patients enhance our understanding of the natural history of pediatric liver diseases.

Acute Disease↗
PubMed1992

Sonographic findings of testicular teratoma with pathologic correlation.

Testicular teratoma is a rare tumor in children. We recently encountered two boys, aged 18 months and 2 years respectively, with this tumor. Sonography revealed an intratesticular mass in both. The first revealed a predominantly cystic lesion with echogenic components along its wall. The second showed a complex mass occupying most of the right testicle, and containing several areas of calcifications and cysts. Excellent pathologic correlation was obtained in both. Preoperative diagnosis of testicular teratoma is possible if the characteristic features are recognized. The prognosis is good following orchiectomy in the pediatric patients.

Child, Preschool↗
PubMed1992

Treatment of children with homozygous familial hypercholesterolemia: safety and efficacy of low-density lipoprotein apheresis.

We evaluated the safety and efficacy of dextran sulfate low-density lipoprotein (LDL) apheresis in the treatment of three children (aged 6, 7, and 10 years) with severe familial homozygous hypercholesterolemia and undetectable LDL receptor activity. A total of 35 double plasma volume procedures were performed. The ranges of the mean decreases of the three patients in plasma lipid concentrations after LDL apheresis (p less than 0.0001) were as follows: total cholesterol, 76% to 79%; LDL-cholesterol, 78% to 81%; very low density lipoprotein cholesterol, 69% to 75%; high-density lipoprotein cholesterol, 27% to 40%; and triglycerides, 34% to 68%. There were statistically significant but clinically and biologically irrelevant changes in hematologic indexes, serum chemistry values, immunoglobulin levels, complement activity, and plasma concentrations of fat-soluble vitamins. Simple correlation analysis of the variables affecting total cholesterol removal showed significant correlation coefficients (r values) for preapheresis total cholesterol values (r = 0.70; p less than 0.01) and preapheresis LDL-cholesterol values (r = 0.61; p less than 0.01). A multiple regression model explained 82% of the variance based on the preapheresis cholesterol concentration, volume of whole blood processed, and the serum albumin concentration. Side effects of the LDL-apheresis treatments were rare and included abdominal cramping and urticaria. Two procedures were aborted because of intravenous access problems in the younger children. This study confirms that LDL apheresis using a dextran sulfate affinity column is efficacious in rapidly lowering total and LDL-cholesterol concentrations. Furthermore, the procedure is safe and well tolerated by children as young as 6 years of age. This treatment may prevent the progression of atherosclerosis in children with homozygous familial hypercholesterolemia and may therefore avert early death.

Blood Component Removal↗
PubMed1992

Post-transplant recurrent hepatitis B viral liver disease. Viral-burden, steatoviral, and fibroviral hepatitis B.

Recurrence of hepatitis is a well-documented complication of hepatitis B liver disease, post-transplantation. It is well established also that the earliest hepatocellular change is the appearance of hepatitis B viral (HBV) markers and that the disease is rapidly progressive. In this article on 17 liver transplants in 16 HBV positive patients with long-term follow-ups (100-1234 days), the distinctive pathologic features of this disease are emphasized: the extreme viral load, the steatosis, and/or fibrosis. An attempt to quantitate the magnitude of the viral burden was made and the result was a staggering figure. In one patient, an estimated 10(18) HBV core particles were present in the liver. One of two patterns of progression were noted. In four patients in addition to the massive nuclear hepatitis B core antigen (HBcAg) and cytoplasmic hepatitis B surface antigen (HBsAg) positivity, superimposed hepatitic changes led to diffuse hepatic fibrosis (fibroviral hepatitis B); and in another six patients, extraordinary hepatocellular viral marker positivity and steatosis were the hallmarks (steatoviral hepatitis B). Steatosis is not usually considered a feature of HBV liver pathology. These results suggest that more than one type of posttransfusion recurrent hepatitis B liver disease exists pathologically.

Fatty Liver↗
PubMed1991

Syncytial giant-cell hepatitis. Sporadic hepatitis with distinctive pathological features, a severe clinical course, and paramyxoviral features.

BACKGROUND AND METHODS: We describe a new form of hepatitis, occurring in 10 patients over a period of six years, characterized clinically by manifestations of severe hepatitis, histologically by large syncytial giant hepatocytes, and ultrastructurally by intracytoplasmic structures consistent with paramyxoviral nucleocapsids. RESULTS: The patients ranged in age from 5 months to 41 years. The tentative clinical diagnosis before biopsy was non-A, non-B hepatitis in five patients and autoimmune chronic active hepatitis in the others. Five patients underwent liver transplantation; the others died. The diagnosis of syncytial giant-cell hepatitis was established pathologically. The liver cords were replaced in all 10 patients by syncytial giant cells with up to 30 nuclei. In 8 of the 10 the cytoplasm contained pleomorphic particles of 150 to 250 microns, filamentous strands, and particles of 14 to 17 nm with peripherally disposed spikes resembling paramyxoviral nucleocapsids. Structures resembling degenerated forms were found in the other two patients. One of two chimpanzees injected with a liver homogenate from the index patient had an increase in the titer of paramyxoviral antibodies, probably an anamnestic reaction to previous paramyxoviral infection, suggesting that a paramyxoviral antigen but not viable virus was present in the liver homogenate. CONCLUSIONS: Although further virologic studies will be required for precise classification, we believe that paramyxoviruses should be considered in patients with severe sporadic hepatitis.

Acute Disease↗
PubMed1991

The effect of eicosapentaenoic acid consumption on human neutrophil chemiluminescence.

The effect of eicosapentaenoic acid (EPA) on the inflammatory potential of neutrophils was investigated by supplementing the diets of 12 subjects with 2.16 g of EPA or 12 g of olive oil per day for 4 weeks in a double blind crossover study. Neutrophil function as assessed by luminol enhanced chemiluminescence responses to platelet-activating factor (PAF) and formyl-methionyl-leucyl-phenylalanine (FMLP) was significantly reduced after EPA but not after olive oil consumption in the subjects who consumed EPA first. In contrast, EPA had no significant effect on neutrophil chemiluminescence in the subjects who consumed olive oil first. Dietary supplementation with EPA inhibits neutrophil responses to inflammatory mediators such as PAF while other fatty acids appear to modify the effects of EPA.

Adult↗
PubMed1991

Fibrolamellar carcinoma of the liver in a patient with Fanconi anemia.

A 9-year-old boy with Fanconi anemia treated with oxymethalone, a synthetic androgen, died of intracerebral hemorrhage. At autopsy, the liver contained several adenomas and a large fibrolamellar hepatocellular carcinoma, as well as phlebectatic peliosis hepatis. The 11 previously reported cases of hepatocellular carcinoma in Fanconi anemia were not, apparently, of the fibrolamellar type, which has a better prognosis, occurs in children of both sexes, and generally is not associated with cirrhosis. The malignant potential of primary liver tumors associated with Fanconi anemia as well as the nature of their relationship to Fanconi anemia and to anabolic steroid therapy is discussed.

Carcinoma, Hepatocellular↗
PubMed1991

Motility of bile canaliculi in the living animal: implications for bile flow.

Modern fluorescence microscopic techniques were used to image the bile canalicular system in the intact rat liver, in vivo. By combining the use of sodium fluorescein secretion into bile, with digitally enhanced fluorescence microscopy and time-lapse video, it was possible to capture and record the canalicular motility events that accompany the secretion of bile in life. Active bile canalicular contractions were found predominantly in zone 1 (periportal) hepatocytes of the liver. The contractile movements were repetitive, forceful, and appeared unidirectional moving bile in a direction towards the portal bile ducts. Contractions were not seen in the network of canaliculi on the surface of the liver. Cytochalasin B administration resulted in reduced canalicular motility, progressive dilation of zone 1 canaliculi, and impairment of bile flow. Canalicular dilations invariably involved the branch points of the canalicular network. The findings add substantively to previous in vitro studies using couplets, and suggest that canalicular contractions contribute physiologically to bile flow in the liver.

Animals↗