Lithium reduction of the bowl-shaped C60 fragment diindeno[1,2,3,4-defg;1',2',3',4'-mnop]chrysene: an interplay between experiment and calculation.

Diindeno[1,2,3,4-defg;1',2',3',4'-mnop]chrysene (DIC) (one of the smallest symmetrical bowl-shaped fragments of C60) and its tetra-tert-butyl derivative are reduced with lithium metal to yield dianions and tetraanions. Due to the high degree of symmetry (C2v) of DIC and its derivative, their NMR spectra cannot be assigned using the standard two-dimensional NMR techniques. A novel carbon-edited NOESY method was used to complete the assignments of the neutral and dianion species, whereas the tetraanions are aided by DFT calculations for their assignment. Experimental charge-distribution patterns were obtained and match those of the calculations. An extension of the empirical approach for estimating the charge distribution from the 13C NMR spectra enables a direct comparison between experimentally derived charge-distribution data and the computed electron density in each of the lowest unoccupied molecular orbitals. The overall picture evolving from the orbital structure of DIC is presented and reflects the surface reactivity of C60.

Postinfantile giant cell hepatitis complicating ulcerative colitis: a case report and review of the literature.

Giant cell hepatitis is common in the neonatal period. When present in adults, it is known as postinfantile giant cell hepatitis (PGCH). PGCH can arise in the context of viral, drug-related, and autoimmune disorders but, in many other cases, its etiology remains unclear. We report a case of PGCH occurring in the setting of autoimmune hepatitis and ulcerative colitis. This case highlights the close association between PGCH and autoimmune disorders and the need to recognize it as a hepatic complication of inflammatory bowel disease.

Hybrid classification of sphincter of Oddi dysfunction based on simplified Milwaukee criteria: effect of marginal serum liver and pancreas test elevations.

To date, when using the Milwaukee classification for sphincter of Oddi dysfunction (SOD), one cannot accurately classify patients with marginal elevations in laboratory tests; ie, < 1.5 x the upper limit of normal (ULN). Since subsequent treatment may depend on how they are classified, we sought to determine whether these patients should be considered as type II or type III. Between January 1993 and October 1996, 113 consecutive patients (82 females and 31 males; ages 12-87 years) without prior sphincterotomy were referred to consider a diagnosis of SOD type II or III. SOD II patients had pancreaticobiliary-type pain and laboratory elevations >1.5 x ULN or dilated ducts, while SOD III patients had pain only. Hybrid patients had pain and marginal laboratory elevations <1.5 x ULN, with normal duct diameters. Drainage times, frequency, duration, and propagation were not assessed. Sphincter of Oddi manometry (SOM) was performed in each case, and the frequency of abnormal biliary and/or pancreatic basal sphincter pressure was compared, with respect to type II, III, and hybrid SOD. Successful SOM was obtained in 113/114 patients: Abnormal basal sphincter pressure was found in 65, 89, and 43% of type II, hybrid, and type III SOD, respectively. We found no statistical difference between type II and hybrid patients. In contrast, there was statistical difference between types II and III patients and between type III and hybrid patients. In conclusion, there was no significant difference in the frequency of elevated basal sphincter pressure in SOD type II versus hybrid, and thus they should be considered as one group.

[Paraneoplastic subacute cerebellar degeneration: case report]. / Degeneração cerebelar subaguda paraneoplásica: relato de caso.

We report a 40-year-old woman with subacute cerebellar degeneration associated with ovarian cancer. We briefly review the clinical and laboratory features of this syndrome, and emphasize the importance of its prompt recognition, which many times makes possible the early detection and treatment of the primary disorder.

ERCP and stent therapy for progressive jaundice in hepatocellular carcinoma: which patients benefit, which patients don't?

Jaundice in hepatocellular carcinoma (HCC) can be due to biliary obstruction. Endoscopic retrograde cholangiopancreatography (ERCP) can be both diagnostic and therapeutic. Biliary stenting can relieve jaundice and allow further chemotherapy, but at additional expense and potential morbidity. We sought to determine whether CT scan or ultrasound (US) could identify which patients with HCC and jaundice would benefit from endoscopic stenting. We retrospectively analyzed 26 patients with HCC and jaundice who underwent ERCP after CT or US. We compared biliary dilation on CT or US with the dominant biliary stricture seen on ERCP, and with response to biliary stenting. Eleven of 26 patients had dominant biliary stricture on ERCP; 11 underwent stenting. Six of 11 (55%) stented patients had a significant decline in bilirubin; three became eligible for further chemotherapy. All six responders to stenting had biliary dilation on prior CT or US. Procedure-related complications occurred in 1/11 (9%) who underwent stent placement. In conclusion, in selected patients, stenting can safely relieve jaundice and allow subsequent chemotherapy. CT or US accurately predicted lesions that responded to stenting. ERCP and stenting provided no benefit in the absence of biliary dilation on CT or US.

The effect of endoscopic sphincterotomy on acute and chronic complications of biliary endoprostheses.

BACKGROUND: Endoscopically placed biliary stents have become routine therapy for bile duct obstruction and bile leaks. Controversy exists regarding the use of biliary sphincterotomy to facilitate placement of 10F plastic stents. METHODS: We retrospectively studied the effect of sphincterotomy on acute and chronic complications of 10F stent therapy. Data for acute complications, 30-day mortality and stent migration were obtained for 130 patients undergoing placement of a single 10F plastic biliary stent. For 109 patients in whom prolonged stent therapy was undertaken, the occurrence of and time to stent dysfunction were also analyzed. Sphincterotomy was performed in 48 cases (36.9%) based on physician preference. RESULTS: There were no failures in stent placement. The incidence of acute complications was higher in patients undergoing sphincterotomy (8.3% vs. 1.2%, p = 0.04). Stent migration was more common in the no sphincterotomy group versus the sphincterotomy group (8.5% vs. 0, p = 0.03). CONCLUSIONS: Sphincterotomy is not necessary for placement of 10F plastic stents and increases acute procedural morbidity. Interestingly, a higher incidence of stent migration was seen in patients who did not undergo biliary sphincterotomy.

Cold-temperature plastic resin embedding of liver for DNA- and RNA-based genotyping.

The standard practice of tissue fixation in 10% formalin followed by embedding in paraffin wax preserves cellular morphology at the expense of availability and quality of DNA and RNA. The negative effect on cellular constituents results from a combination of extensive cross-linking and strand scission of DNA, RNA, and proteins induced by formaldehyde as well as RNA loss secondary to ubiquitous RNase activity and negative effects of high temperature exposure during paraffin melting, microscopic section collection, and tissue adherence to glass slides. An effective strategy to correlate cellular phenotype with molecular genotype involves microdissection of tissue sections based on specific histopathological features followed by genotyping of minute representative samples for specific underlying molecular alterations. Currently, this approach is limited to short-length polymerase chain reaction amplification (<250 bp) of DNA, due to the negative effects of standard tissue fixation and processing. To overcome this obstacle and permit both cellular morphology and nucleic acid content to be preserved to the fullest extent, we instituted a system of cold-temperature plastic resin embedding based on the use of the water-miscible methyl methacrylate polymer known as Immunobed (Polysciences, Warminster, PA). The system is simple, easy to adapt to clinical practice, and cost-effective. Immunobed tissue sections demonstrate a cellular appearance equivalent or even superior to that of standard tissue sections. Moreover, thin sectioning (0.5-1.0 microm thickness) renders ultrastructural evaluation feasible on plastic-embedded blocks. Tissue microdissection is readily performed, yielding high levels of long DNA and RNA for genomic and transcription-based correlative molecular analysis. We recommend the use of Immunobed or similar products for use in molecular anatomical pathology.

Gastrointestinal bleeding in cirrhotic patients with hepatocellular carcinoma undergoing intrahepatic artery chemotherapy.

BACKGROUND: Hepatocellular carcinoma in cirrhotic patients increases the risk of variceal bleeding. We sought to characterize bleeding in a cirrhotic patient population undergoing intrahepatic artery chemotherapy for hepatocellular carcinoma and to determine the possible influence of this treatment on gastrointestinal bleeding. METHODS: We retrospectively reviewed 179 patients with hepatocellular carcinoma who underwent intrahepatic artery doxorubicin and cis-platinum chemotherapy to determine the incidence of gastrointestinal bleeding and compared them with 434 hepatocellular carcinoma historic controls not undergoing regional chemotherapy. RESULTS: Of the 179 patients, 27 patients (15.1%) developed upper gastrointestinal bleeding over a mean follow-up of 15.2 months; 18 of the 27 (66.7%) bled from a variceal source and 9 (33.3%) bled from a nonvariceal source: ulcer (n = 6), gastropathy (n = 1), Mallory-Weiss (n = 1), erosive gastritis (n = 1). Twenty-one patients developed bleeding after initiation of chemotherapy (14 variceal and 7 nonvariceal). The number of chemotherapy sessions among patients with variceal and nonvariceal bleeding was similar (2.1 +/- 0.4 and 4.0 +/- 1.2; p = Not significant). Patients with variceal and nonvariceal bleeding were comparable with respect to Child-Pugh classification, pTNM stage, age, time to bleeding, and gender. CONCLUSIONS: Regional intra-arterial chemotherapy for hepatocellular carcinoma is associated with a low risk of variceal bleeding. Nonvariceal sources of upper gastrointestinal bleeding in this population account for a significant component of bleeding episodes.

Granulomatous hepatitis in a patient with chronic hepatitis C treated with interferon-alpha.

Common adverse effects of IFN-alpha include flulike symptoms, headache, irritability, and bone marrow suppression. Hepatic side effects are unusual except in patients with pretreatment autoimmune hepatitis. Granuloma formation in the liver as a result of IFN-alpha therapy has never been reported. We described a 48-year-old female with chronic hepatitis C infection who developed granulomatous hepatitis following treatment with IFN-alpha. The granulomatous inflammation resolved after discontinuation of IFN-alpha treatment. Possible mechanisms for this unusual occurrence are discussed.

Effects of liver disease on the disposition of the opioid antagonist nalmefene.

OBJECTIVES: The pharmacokinetics of nalmefene and its glucuronide metabolite were investigated in 12 patients with liver disease (four patients with mild, five patients with moderate, and three patients with severe liver disease) and 12 age-, weight-, and gender-matched control subjects. METHODS: Subjects received a single intravenous bolus 2.0 mg dose of nalmefene. Multiple blood and urine samples were collected for 48 hours. Within 1 week of nalmefene administration, antipyrine and galactose clearances were determined as general markers of hepatic metabolism and effective liver plasma flow, respectively. Plasma concentrations of nalmefene were determined by radioimmunoassay. RESULTS: The antipyrine and galactose clearance values were 56% and 33% lower, respectively, in the patients with liver disease compared with the normal healthy control subjects. The systemic clearance of nalmefene was reduced by 32% (0.61 +/- 0.21 versus 0.90 +/- 0.27 L/hr/kg [mean +/- SD]) and the terminal elimination half-life was increased by 31% (10.5 +/- 1.9 versus 8.0 +/- 2.2 hours) in the patients with liver disease. This was primarily the result of a 31% reduction (0.181 +/- 0.067 versus 0.263 +/- 0.072 L/hr/kg) in nalmefene glucuronide formation clearance. There were no significant differences in nalmefene volumes of distribution or protein binding. There was a significant inverse relationship between nalmefene clearance and Pugh score (r = -0.57; p = 0.004), indicating decreasing nalmefene clearance with increasing severity of liver disease. CONCLUSIONS: The clearance of nalmefene was significantly reduced in the presence of liver disease. However, because nalmefene will be primarily used in the acute care setting for reversal of opioid-induced effects, it is not likely that these alterations will necessitate a dosage modification.

Candida albicans osteomyelitis in a liver transplant recipient: a case report and review of the literature.

A 51-year-old man developed fever and back pain 2 months after orthotopic liver transplantation for end-stage liver disease secondary to chronic hepatitis C infection. CT scan demonstrated destructive lesions in T12 suggestive of osteomyelitis. Aspiration biopsy of the vertebra revealed granulomatous inflammation and yeast forms; culture yielded Candida albicans. The patient improved with intravenous amphotericin B and 5-fluorocytosine and did not require surgical intervention. Candida osteomyelitis is a rare condition and to our knowledge it has not been reported before in liver transplant recipients. Awareness of this potential complication may shorten the delay in making the definitive diagnosis, which in turn may increase the likelihood of a response without sequela.

alpha-Interferon retreatment of patients with chronic hepatitis C.

To evaluate the effect of a second cycle of alpha-IFN treatment on patients who have not responded to a first cycle or responded and relapsed, 37 patients, 25 men and 12 women, mean age 41 yr, were retreated with alpha-interferon (IFN). Seven patients responded to the first cycle of treatment, and 30 did not. Five patients who had not responded to the second cycle received a third one. All patients received twice the dose of the first cycle unless they experienced side effects during the first cycle. Thus, nine patients received 9 mU/w, nine received 15 mU/w, and 19 received 30 mU/w for 6 months. Complete response was defined as nondetectable hepatic hepatitis C virus (HCV)-RNA at the end of therapy; sustained response was defined as normal ALT levels with negative serum HCV-RNA at > 6 months after cessation of therapy. Of the 30 nonresponders to the first cycle, eight responded to the second, but only four (13%) had a sustained response. Six of the seven responders to the first cycle responded to the second cycle, but only three had a sustained response (3/7, 43%) (p = NS). Although 33 and 21% (p = NS) of those who were treated with 15 mU/w and 30 mU/w, respectively, showed a sustained response, none of those treated with 9 mU/w had a sustained response (p = NS). Although age or sex of the patients studied had no effect on the response rate, liver histology was an important factor because only noncirrhotics showed a long term response (47 vs 0%; p < 0.02). There was no difference in response rate between patients with chronic active hepatitis and chronic persistent hepatitis. In conclusion, noncirrhotic patients who have not responded or responded and relapsed to a 6-month course of alpha-INF (3-5 mU three times per week) should try a second course at a dose of 15 mU/w. Retreatment may induce complete and long lasting response in 13% of the initial nonresponders and 43% of the initial responders. A second course of alpha-IFN in nonresponding cirrhotics appears ineffective in clearing the virus at the doses used.

Uncharged tRNA-phosphofructokinase interaction in amino acid deficiency.

When the tRNA of mammalian cells is incompletely charged due to amino acid deficiency or by analogs which cannot be activated, many metabolic events become limited. This rapid demise of cell function appears to be due to the inhibition of phosphofructokinase (PFK) by uncharged tRNA (FEBS Lett 302: 113 (1992)). Charged tRNA has been shown to be "sequestered within the protein synthetic machinery", (Negrutskii, B. S. and Deutscher, M. P. (1992) Proc Natl Acad Sci USA 89: 3601) and would therefore be removed from an inhibitory role. Besides the direct demonstration that tRNA inhibits PFK in an assay regarded as indicative of its control mechanism, several reports in the literature support this model. These include 1) The rapid onset of inhibition of glycolysis and glucose uptake by intact cells upon amino acid deficiency and the similar lesion at the 43S ribosomal subunit on glucose or amino acid deprivation. 2) The recognition that unusually high concentrations of cAMP required to stimulate protein synthesis in energy depleted or gel filtered lysates correlates with its action on PFK as an analog of the positive effector, adenosine-5'-monophosphate. 3) The often repeated observation that the product of PFK activity, fructose-1,6-diphosphate, is a stimulant of protein synthesis (see Jackson, R. J., et al. (1983) Eur J Biochem 131: 289). This diphosphate has been shown to be the proximate effector binding to eIF-2B, the guanine nucleotide exchange factor (Singh, L. P. Arror, A. R. and Wahba, A. J. (1994), FASEB J. 8: 279) which by releasing GDP bound to the inactive GDP: eIF-2 complex, permits the factor to initiate a new peptide chain. The above information supports the view that the block at the G1 restriction point in the cell cycle of normal cells brought about by amino acid deprivation is a result of inhibition of protein synthesis through the phosphofructokinase-uncharged tRNA mechanism. This is consistent with observations in the literature that tumor and transformed cells, which are more resistant to this block (Pardee, A. B., Proc Natl Acad Sci USA 71: 1286-1291 (1974)) have a higher phosphofructokinase activity or higher levels of fructose-1,6-diphosphate.

Primary biliary cirrhosis diagnosed during pregnancy. Does it have a different outcome?

Pregnancy in women with primary biliary cirrhosis (PBC) is uncommon, and once it occurs it usually does not worsen the liver disease. First manifestation of PBC during pregnancy in women with no known liver disease at the time of conception is very rare, and the natural history of this disease in such cases is yet unknown. Herein we describe a woman who had been diagnosed with PBC during the third trimester of pregnancy and, while she gave birth to a normal healthy child, her disease rapidly deteriorated and she has been listed for liver transplantation. It appears that PBC that is first noted during pregnancy might have a different course than that of PBC diagnosed before pregnancy.

Biliary tract calculi in primary sclerosing cholangitis.

UNLABELLED: By conventional criteria the diagnosis of primary sclerosing cholangitis (PSC) is excluded if biliary tract calculi are present. OBJECTIVE: To compare patients with sclerosing cholangitis with and without calculi. METHODS: Retrospective review between 8/91 and 9/93 identified 63 patients with sclerosing cholangitis alone (Group A) and 22 patients with sclerosing cholangitis and biliary tract calculi (Group B). The mean follow-up was 13.6 months. Clinical features reviewed were age, sex, associated inflammatory disease (IBD), and clinical presentation. Cholangiographic features compared were site and extent of disease. Endoscopic stone extraction was reviewed for success and complications. RESULTS: Both groups had the following features in common: 1) mean age (45.9 vs 46.3 yr), 2) prevalence of IBD (68.3 vs 72.7%), 3) extent of bile duct strictures (intrahepatic: 28.5% vs 27.2%; extrahepatic: 12.7% vs 13.6%; both: 58.7% vs 54.5%). There were proportionately more women in Group B (45.5% vs 33.3%). Symptomatic presentation (pain, pruritus, jaundice, and cholangitis) was seen more often in Group B: 86.4% compared with Group A: 39.7% (specifically cholangitis was seen in 22.7% vs 4.7%). Among Group B, calculi developed subsequent (mean 40.2 months) after the diagnosis of sclerosing cholangitis in 77.3% of patients. The distribution of calculi was cholelithiasis: 7 (31.8%); choledocholithiasis: 9 (40.9%); and both: 6 (27.2%). Of the patients with choledocholithiasis alone, 78% had undergone previous cholecystectomy. Endoscopic stone extraction was successful in 13 (86.6%) of the patients with choledocholithiasis. Complications included mild pancreatitis in one patient and bleeding from sphincterotomy site in another patient which responded to sclerotherapy. In follow-up, only one patient had recurrent calculi and underwent successful stone extraction. CONCLUSION: We suggest that biliary tract calculi are a part of the spectrum of otherwise typical PSC and therefore their presence should not necessarily exclude the diagnosis.

Inhibition of human immunodeficiency virus type 1 integrase by a hydrophobic cation: the phenanthroline-cuprous complex.

The human immunodeficiency virus type 1 integrase (HIV-1 integrase) is required for integration of a double-stranded DNA copy of the viral RNA genome into a host chromosome and for HIV replication. We have examined the effects of 2:1 1,10-phenanthroline-cuprous complexes on purified HIV-1 integrase. Although the uncomplexed phenanthrolines are not active below 100 microM, four of the cuprous complexes (neocuproine, 4-phenyl neocuproine, 2,3,4,7,8,9-hexamethyl phenanthroline, and 2,3,4,7,8-pentamethyl phenanthroline) have a 50% inhibitory concentration (IC50) for integration ranging between 1 and 10 microM. Disintegration is also inhibited by these phenanthroline-cuprous complexes at slightly higher concentrations (between 10 and 40 microM). Dialysis experiments showed that the inhibition is reversible and kinetic analyses revealed that the mode of inhibition by these cuprous complexes appears to be noncompetitive with respect to the substrate DNA. Consistent with these findings, binding assays demonstrate that, although these complexes can inhibit binding to DNA at high concentrations, they do not inhibit binding of integrase to the DNA substrate at their IC50 values. Because these complexes do not bind to B-DNA below 50 microM, inhibition via binding to a specific region on the enzyme was examined. Using deletion mutants of integrase, it was determined that neither the amino-terminal (zinc finger) nor the carboxy-terminal (DNA-binding) integrase domain is required for inhibition by the phenanthroline-cuprous complexes. Therefore, inhibition via binding to the enzyme catalytic core or to the interface between the enzyme and a noncanonical DNA structure generated during the enzymatic reaction is the probable mechanism. These results suggest the utility of neocuproine-cuprous complexes in developing inhibitors of HIV-1 integrase as well as probes for drug-binding sites and enzymatic reaction mechanism.

The phosphofructokinase-uncharged tRNA interaction in metabolic and cell cycle control: an interpretive review.

When the tRNA of mammalian cells is incompletely charged due to amino acid deficiency or by analogs which cannot be activated, many metabolic events become limited. This rapid demise of cell function appears to be because of the inhibition of phosphofructokinase (PFK) by uncharged tRNA (FEBS Lett. 302: 113 (1992)). Charged tRNA has been shown to be "sequestered within the protein synthetic machinery", (Negrutskii, B.S. and Deutscher, M.P., Proc. Natl. Acad. Sci. USA 89 3601 (1992) and would therefore be removed from an inhibitory role. Besides the direct demonstration that tRNA inhibits PFK in an assay regarded as indicative of its control mechanism, several reports in the literature support this model. These include 1) The rapid onset of inhibition of glycolysis and glucose uptake by intact cells upon amino acid deficiency and the similar lesion at the 43S ribosomal subunit on glucose or amino acid deprivation. 2) The recognition that unusually high concentrations of cAMP required to stimulate protein synthesis in energy depleted or gel filtered lysates correlates with its action on PFK as an analog of the positive effector, adenosine-5'-monophosphate. 3)The often repeated observation that the product of PFK activity, fructose-1,6-diphosphate, is a stimulant of protein synthesis (see Jackson, R.J., et al. Eur. J. Biochem. 131: 289-313 (1983)). This diphosphate has been shown to be the proximate effector binding to eIF-2B, the guanine nucleotide exchange factor (Singh, L.P. Arror, A.R. and Wahba, A.J., FASEB J. 8 279 (1994)) which by releasing GDP bound to the inactive GDP:eIF-2 complex, permits the factor to initiate a new peptide chain. The above information supports the view that the block at the G1 restriction point in the cell cycle of normal cells brought about by amino acid deprivation is a result of inhibition of protein synthesis through the phosphofructokinase-uncharged tRNA mechanism. This is consistent with observations in the literature that tumor and transformed cells, which are more resistant to this block (Pardee, A.B., Proc. Natl. Acad. Sci. U.S.A. 71:1286-1291 (1974)) have a higher phosphofructokinase activity or higher levels of fructose-1,6-diphosphate.

Postinfantile giant cell hepatitis associated with anti-M2 mitochondrial antibodies.

Whereas giant cell hepatitis (GCH) is a common diagnosis made in neonates, it is rare in the adult population. The diagnosis of GCH is based on the presence of giant cell transformation of hepatocytes. It is commonly associated with either viral hepatitis or autoimmune disorders. A patient with GCH who had anti-M2 mitochondrial antibodies is described. This combination, which has not been previously reported, underscores the association of GCH with autoimmune disorders and stresses the importance of corticosteroids as an empirical initial therapy.