Giant cells in pyoderma gangrenosum.

It has been claimed that pyoderma gangrenosum (PG) lesions may contain granulomatous foci when associated with Crohn's disease. To test this assertion, we obtained clinical histories and archived cutaneous biopsies from 34 PG patients. Thirteen of these patients had inflammatory bowel disease (IBD). Immunostaining with PGM1, a macrophage marker, revealed well-formed giant cells with three or more nuclei in biopsies from 6 of 13 patients with IBD. Five of the 6 biopsies came from patients with Crohn's disease and one from a patient with ulcerative colitis. Two were peristomal. In the 21 patients who had PG without IBD, no giant cells were seen. Thus, PGM1+ histiocytic giant cells within a PG lesion may be indicative of associated IBD (p = 0.006), particularly Crohn's disease.

Recurrent hepatitis B, hepatitis C, and combined hepatitis B and C in liver allografts: a comparative pathological study.

Although recurrence of viral hepatitis in liver transplants is common, data comparing recurrent hepatitis B (HB), hepatitis C (HC), and co-existing dual hepatitis B and C (HB&C) are sparse. Posttransplantation liver biopsies, along with molecular, serological, immunohistochemical, and clinical data from 27 patients with pretransplantation diagnosis of chronic viral hepatitis, were reviewed. The patients were placed into 4 groups: Group I, with pretransplantation HB (n = 8); group II, with pretransplantation HC (n = 10); group III with pretransplantation HC and anti-HB surface or core antibody (n = 4); and group IV, with pretransplantation HB&C (n = 5). The histopathologic findings and patient outcome were compared in the 4 groups. A high rate of recurrence of viral hepatitis was seen for all 4 groups: Group I = 100%, group II = 90%, Group III = 100%, and group IV = 80%, with the mean (median) recurrence time of 308 (224), 82 (52), 61 (64), and 125 (70) days, respectively. The number of deaths (their median survival times) were: group I = 4 (374 days), group II = 4 (794 days), group III = 1 (1,143 days), and group IV = 5 (448 days). The earliest histological findings of lobular injury was the presence of acidophil bodies and Kupffer cell hyperplasia, the latter being more prominent in recurrent HC cases. Recurrent HB presented in 2 forms: early (before 150 days) with poor survival and with either severe necroinflammatory histology or with features of fibrosing cholestatic hepatitis, and delayed (after 150 days), with mild necro-inflammatory activity and prolonged survival. HC with or without anti-HB antibodies had early recurrence, but the course was slowly progressive. Patients with HB&C had recurrence of both viruses; however, the course was dictated by HB virus.

Activation of nuclear factor kappa B and cytokine imbalance in experimental alcoholic liver disease in the rat.

Inflammatory stimuli and lipid peroxidation activate nuclear factor kappa B (NF-kappaB) and upregulate proinflammatory cytokines and chemokines. The present study evaluated the relationship between pathological liver injury, endotoxemia, lipid peroxidation, and NF-kappaB activation and imbalance between pro- and anti-inflammatory cytokines. Rats (5 per group) were fed ethanol and a diet containing saturated fat, palm oil, corn oil, or fish oil by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. Pathological analysis was performed and measurements of endotoxin were taken, lipid peroxidation, NF-kappaB, and messenger RNA (mRNA) levels of proinflammatory cytokines (tumor necrosis factor-alpha [TNFalpha], interleukin-1 beta [IL-1beta], interferon-gamma, [IFN-gamma], and IL-12), C-C chemokines (regulated upon activation, normal T cell expressed and secreted [RANTES], monocyte chemotactic protein [MCP]-1, macrophage inflammatory protein [MIP]-1alpha), C-X-C chemokines (cytokine induced neutrophil chemoattractant (CINC), MIP-2, IP-10, and epithelial neutrophil activating protein [ENA]-78), and anti-inflammatory cytokines (IL-10, IL-4, and IL-13). Activation of NF-kappaB and increased expression of proinflammatory cytokines C-C and C-X-C chemokines was seen in the rats exhibiting necroinflammatory injury (fish oil-ethanol [FE] and corn oil-ethanol[CE]). These groups also had the highest levels of endotoxin and lipid peroxidation. Levels of IL-10 and IL-4 mRNA were lower in the group exhibiting inflammatory liver injury. Thus, activation of NF-kappaB occurs in the presence of proinflammatory stimuli and results in increased expression of proinflammatory cytokines and chemokines. The Kupffer cell is probably the major cell type showing activation of NF-kappaB although the contribution of endothelial cells and hepatocytes cannot be excluded. Downregulation of anti-inflammatory cytokines may additionally exacerbate liver injury.

S100+ cell response to squamous cell carcinoma of the lip: inverse correlation with metastasis.

Previous work has suggested a key role of dendritic cells in antineoplastic immunity. The course of mycosis fungoides and cancers of the lung, colon, thyroid and stomach has been associated with dendritic cell response to the primary tumor. However, this has not been reported for cutaneous or mucosal squamous cell carcinoma (SCC). Thirty-six cases of primary SCC of the lip mucosa or vermillion border, including nine cases with regional metastasis, were studied to investigate the relationship of dendritic cell density with age, tumor grade, mitotic rate, diameter, ulceration, depth of invasion, muscle invasion, tumor-infiltrating lymphocytes (TILs) and metastasis. Dendritic cells were identified using S100 immunohistochemistry, and their peritumor and intratumor density (peri-S100D and intra-S100D) were determined. The mean peri-S100D was 314 +/- 50/mm2. High peri-S100D was associated with lower rate of metastasis (P = 0.03), and no case with peri-S100D > 311/mm2 metastasized. Peri-S100D inversely correlated with depth of invasion (P = 0.04) and ulceration (P = 0.02), and positively associated with TILs (P = 0.02). The mean intra-S100D was 317 +/- 42/mm2. Intra-S100D did not quantitatively correlate with metastasis; however, no metastasis occurred when intra-S100D exceeded 515/mm2. Intra-S100D correlated with brisk TILs (P = 0.04). These results suggest a functional role of dendritic cells in the immune response to SCC. Peri-S100D may be a prognostic indicator.

Protothecosis: an unusual cause of chronic subcutaneous and soft tissue infection.

Protothecosis of subcutaneous and soft tissues is a rare occurrence in humans. We present two patients with chronic subcutaneous protothecosis affecting the elbow and foot respectively. Both patients had been treated with local corticosteroid injections and had recent exposure to water. The diagnosis was made histopathologically in both cases and confirmed by culture in one case. Histopathology showed typical Protothecal sporangia with surrounding mixed inflammatory infiltrate including necrotizing granulomas. Organisms stained positively with periodic acid-schiff, Gomori's methenamine silver, and Gridley fungus stains. In one case, intravenous chemotherapy was required to eliminate the pathogens. Histopathologic identification of the organisms is vital to ensure adequate therapy and avoid chronic smoldering infection.

Microscopic localization of calcifications in and around breast carcinoma: a cautionary note for needle core biopsies.

OBJECTIVE: To detail the microanatomic localization of microcalcifications (Ca++) occurring in association with breast carcinoma and thereby to determine their reliability as a marker of breast carcinoma in small tissue core biopsies. SUMMARY BACKGROUND DATA: Identification of the pathology associated with Ca++ in mammograms has acquired increasing importance in the early detection of breast carcinoma. With recent advances enabling computer-guided stereoscopic needle biopsy of calcified foci, histopathologic diagnosis is rendered on increasingly small tissue samples, raising the risk of misdiagnosis. Knowledge of the microanatomic distribution of Ca++ in relation to diagnostic epithelial elements is essential for assessing their significance in small tissue biopsies. METHODS: All 32 carcinomas with Ca++ within 1 cm of carcinoma diagnosed by open biopsy at the New England Deaconess Hospital from January 1994 to January 1995 were studied. Ca++ were classified as being within ductal or lobular carcinoma in situ, invasive carcinoma, carcinoma-associated stroma, benign stroma >1 mm from carcinoma, or benign ducts or terminal duct-lobular units. If Ca++ were peritumoral, their distance from the tumor was measured. RESULTS: Ca++ were present only in malignant components in 31%, only in benign components in 34%, and in both in 34% of cases. The most common locations of Ca++ were benign peritumoral ducts (62%) and ductal carcinoma in situ (54%). The microanatomic distribution of benign peritumoral Ca++ in relation to the mass is detailed. CONCLUSIONS: In carcinomas with Ca++ in the area of tumor, Ca++ may not be localized to malignant tissue. Caution should be used when interpreting the finding of Ca++ in benign components of small tissue samples of breast masses.

Plantar verrucous carcinoma following transmetatarsal amputation and renal transplantation.

Verrucous carcinoma is a rare, low-grade, well-differentiated squamous cell carcinoma that may occur anywhere on the skin. It is slow growing, enlarges relentlessly, and invades locally. Most cutaneous verrucous carcinomas are found on the plantar surface of the foot, and share many gross and histological characteristics common to the ubiquitous verruca vulgaris. It is not uncommon for verrucous carcinoma of the sole to be mistaken for the more common verruca plantaris. The case of a 53-year-old white male with plantar verrucous carcinoma following cadaveric renal transplantation, right popliteal-tibial bypass, and a right transmetatarsal amputation is presented. Treatment included reamputation followed by reconstruction with a free radial forearm fasciocutaneous flap. Verrucous carcinoma is a slow-growing but relentlessly invading tumor that is easily misdiagnosed. The extent of early resection is often inadequate. We must be aware that certain persistent "warts" may represent a form of cancer that is treated differently from common verrucae or other squamous carcinomas.

Dietary saturated fatty acids down-regulate cyclooxygenase-2 and tumor necrosis factor alfa and reverse fibrosis in alcohol-induced liver disease in the rat.

We investigated the potential of dietary saturated fatty acids to decrease endotoxemia and suppress expression of cyclooxygenase 2 (Cox-2) and tumor necrosis factor alpha (TNF-alpha) in established alcohol-induced liver injury. Six groups (five rats/group) of male Wistar rats were studied. Rats in group 1 were fed a fish oil-ethanol diet for 6 weeks. Rats in groups 2, 3, and 4 were fed fish oil and ethanol for 6 weeks. Ethanol administration was stopped at this time, and the rats were switched to isocaloric diets containing dextrose with fish oil (group 2), palm oil (group 3), or medium-chain triglycerides (group 4) as the source of fat for an additional 2 weeks. Rats in groups 5 and 6 were fed fish oil-ethanol and fish oil-dextrose, respectively, for 8 weeks. Liver samples were analyzed for histopathology, lipid peroxidation, and levels of messenger RNA (mRNA) for Cox-2 and TNF-alpha. Concentrations of endotoxin were determined in plasma. The most severe inflammation and fibrosis were detected in groups 1 and 5, as were the highest levels of endotoxin, lipid peroxidation, and mRNA for Cox-2 and TNF-alpha. After ethanol was discontinued, there was minimal histological improvement in group 2 but near normalization of the histology, including regression of fibrosis, in groups 3 and 4. Histological improvement was associated with decreased levels of endotoxin, lipid peroxidation, and reduced expression of Cox-2 and TNF-alpha. The data indicate that a diet enriched in saturated fatty acids (groups 3 and 4) effectively reverses alcohol-induced liver injury, including fibrosis. The therapeutic effects of saturated fatty acids may be explained, at least in part, by reduced endotoxemia and lipid peroxidation, which in turn result in decreased levels of TNF-alpha and Cox-2.

Alterations in thromboxane synthase and thromboxane A2 receptors in experimental alcoholic liver disease.

We have previously shown that hepatic thromboxane production is increased in experimental alcoholic liver disease. The present study was designed to investigate the cell type in liver responsible for increased thromboxane synthesis and the role of the thromboxane receptor system in the pathogenesis of liver injury. Male Wistar rats were divided into four groups and fed a liquid diet with dextrose or ethanol for 2, 4 and 8 weeks. Medium chain triglycerides or corn oil provided the dietary fatty acids. Kupffer cells, endothelial cells and hepatocytes were isolated from rats fed the different diets for 4 weeks. Liver histopathology, thromboxane synthase mRNA and protein, thromboxane levels and thromboxane receptor mRNA were evaluated in each group. In rats fed corn oil and ethanol, an increase in thromboxane synthase and liver levels of thromboxane metabolites were significantly higher than in the corn oil-dextrose-fed group and were correlated with the presence of pathological changes in the liver. Kupffer cells showed increased expression of thromboxane synthase. In rats fed medium chain triglycerides and ethanol, the levels of thromboxane synthase mRNA and protein were significantly lower than in the corn oil-ethanol-fed groups (P < .01) and liver injury was absent. However, the levels of thromboxane synthase mRNA, protein and thromboxane were significantly higher in the medium chain triglyceride-ethanol-fed rats than in the respective dextrose-fed controls. Among the different cell types, thromboxane A2-receptor mRNA levels were highest in the Kupffer cells in corn oil-ethanol-fed rats. The increase in thromboxane synthase in Kupffer cells together with an increase in thromboxane receptor levels suggests than thromboxanes may contribute to liver injury in ethanol-fed rats.

Cholesterol supplementation prevents necrosis and inflammation but enhances fibrosis in alcoholic liver disease in the rat.

Based on studies that show a role for the low-density lipoprotein (LDL)-receptor in arachidonic acid delivery and eicosanoid synthesis in macrophages, the present study investigated the effect of cholesterol supplementation on pathological changes and thromboxane (TX) synthesis in alcoholic liver injury. Male Wistar rats were intragastrically fed ethanol with either corn oil or fish oil for 1 month. Control rats received isocaloric amounts of dextrose instead of ethanol. An additional group of rats fed either ethanol or dextrose with fish oil or corn oil were supplemented with 1% cholesterol. At the time of killing, all rats had the following evaluated: liver histopathology, lipid peroxidation, liver and plasma thromboxane levels, plasma endotoxin and messenger RNA (mRNA) levels of LDL-receptor, tumor necrosis factor alpha (TNF-alpha), cyclooxygenase (Cox)-1 and -2, and transforming growth factor beta (TGF-beta). Rats fed ethanol with either fish oil or corn oil developed fatty liver, necrosis, inflammation, and central vein collagen deposition. Cholesterol supplementation enhanced the degree of fibrosis but prevented necrosis and inflammation. These alterations in pathological changes by cholesterol were accompanied by absent TNF-alpha and Cox-2 mRNAs, decreased thromboxane levels, decreased lipid peroxidation, and increased TGF-beta mRNA. Cholesterol enrichment of the diet thus decreases proinflammatory components, but enhances fibrosis in ethanol-fed rats.

Chronic varicella zoster infection mimicking a basal cell carcinoma in an AIDS patient.

Chronic herpesvirus infections are common in patients infected with HIV. Atypical skin lesions secondary to long-standing varicella-zoster virus (VZV) infection have been reported. We present a case of an AIDS patient with a chronic VZV infection that simulated a basal cell carcinoma. Histologic examination and immunohistochemistry confirmed the presence of the virus in the follicular epithelium. In the immunocompromised patient, biopsies should be performed on all suspicious lesions because medically-treatable infections may take on the appearance of malignancy.

Enhanced cyclooxygenase-2 gene expression in alcoholic liver disease in the rat.

BACKGROUND & AIMS: Inflammatory stimuli and lipid peroxidation up-regulate cyclooxygenase (COX)-2. This study evaluated the relationship between inflammatory mediators, COX expression, and pathological changes in experimental alcoholic liver disease. METHODS: Rats (5 per group) were fed ethanol and a diet containing saturated fat, corn oil, or fish oil by intragastric infusion. Dextrose isocalorically replaced ethanol in controls. In the first set of experiments, whole livers were analyzed. In the second set of experiments, Kupffer cells, endothelial cells, and hepatocytes were isolated from rats in each group. Pathological analyses and measurements of lipid peroxidation, tumor necrosis factor (TNF)-alpha, COX-1 and COX-2 messenger RNA (mRNA), endotoxin, and liver and plasma thromboxane were performed. RESULTS: Increased expression of COX-2 mRNA was detected in the livers of rats showing necroinflammatory changes. The Kupffer cell was the cell primarily responsible for the increase in COX-2 mRNA level. Increased expression of COX-2 was associated with increased levels of endotoxin, TNF-alpha mRNA, lipid peroxidation, and synthesis of thromboxane. COX-1 mRNA was decreased in Kupffer cells in rats with the most severe liver injury. CONCLUSIONS: Up-regulation of COX-2 in alcoholic liver injury occurred in the presence of proinflammatory stimuli and resulted in increased synthesis of inflammatory and vasoactive eicosanoids. Down-regulation of COX-1 may result in decreased synthesis of cytoprotective eicosanoids and additionally exacerbate liver injury.

Thromboxane inhibitors attenuate pathological changes in alcoholic liver disease in the rat.

BACKGROUND & AIMS: Thromboxane levels correlate with severity of liver injury in rats given alcohol. The aim of this study was to evaluate the effect of thromboxane inhibitors on pathological changes in experimental alcoholic liver disease. METHODS: Male Wistar rats were given a liquid diet and ethanol intragastrically for 1 month. The thromboxane inhibitors tested were a thromboxane receptor antagonist (TXRA) and a thromboxane synthase inhibitor (TXSI). Pathological changes, liver and plasma thromboxane levels, 6-ketoprostaglandin F1 alpha levels, lipid peroxidation, and messenger RNA levels for tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF) beta were evaluated. RESULTS: Treatment with thromboxane inhibitors prevented necrosis and inflammation. In the TXSI-treated group, fatty liver was also decreased. Ethanol administration led to a 3-4-fold increase in liver thromboxane levels; a reduction in thromboxane levels and lipid peroxidation was seen in the TXSI group. In all treatment groups, TNF-alpha and TGF-beta messenger RNA levels were decreased. CONCLUSIONS: The prevention of necroinflammatory changes in thromboxane-treated groups is related to a decrease in TNF-alpha levels. Inhibition of TGF-beta expression may also prevent fibrosis in ethanol-treated rats.

Association between endothelial cell proliferation and pathologic changes in experimental alcoholic liver disease.

We evaluated the role of endothelial cell (EC) proliferation in experimental alcoholic liver disease (ALD) using different dietary models of ALD. Rats were divided into treatment groups to receive ethanol with either corn oil (CO + E), fish oil (FO + E), saturated fat (SF + E), and corn oil with a novel quinone derivative (E3330) and cimetidine. All ethanol-fed rats in the different groups were pair-fed with dextrose replacing the ethanol-derived calories. All ethanol-fed groups and their controls were fed for periods ranging from 1 to 4 weeks. For each animal, immunocytochemical staining for PCNA was performed on paraffin-embedded tissue sections and the number of endothelial cells staining for PCNA per 10 high-power fields (HPF) was determined. Rats fed CO + E and FO + E developed pathological changes, whereas none of the histologic features of ALD were seen in SF + E rats. The severity of injury was reduced in the quinone and cimetidine-treated groups. A higher rate of EC proliferation (6-30x) was seen in the SF + E group (no liver injury) than in the CO + E and FO + E groups (pathologic changes present). The difference was evident by 1 week, which is well before pathologic changes can be recognized (usually 4 weeks). An increase in EC proliferation was seen in the E3330 and cimetidine-treated groups. Our study indicates that the proliferative response of EC in ethanol-fed rats may be a factor in the progression to liver injury. Suppression of ethanol-induced EC proliferation in CO + E and FO + E groups occurred prior to development of liver injury; a lack of suppression of EC proliferation is associated with absence (SF + E and CO + E + cimetidine) or reduction in severity (CO + E + E3330) of liver injury.

Protein and lipid refeeding changes protein metabolism and colonic but not small intestinal morphology in protein-depleted rats.

In this study, we fed rats a 2% casein AIN 76 diet for 2 wk to produce protein malnutrition. We determined in these animals the effects of different concentrations of dietary protein refeeding (2% and 20% casein) on recovery and gut mucosal repletion and the potential role of type of dietary fat in the regulation of protein metabolism and mucosal growth by providing conventional long-chain triglyceride (LCT), a structured lipid composed of long-, medium- and short-chain fatty acids (SC/SL), or a physical mixture of the same components present in the structured lipid given as individual pure triglycerides (SC/PM) along with adequate amounts of protein and energy. The results confirmed that protein malnutrition can be reversed rapidly by protein refeeding, as indicated by an increase in body weight, positive nitrogen balance, liver growth and elevations in plasma concentrations of insulin-like growth factor-1, leucine and albumin. In the colon, crypt cell number, crypt depth and number of crypt cells in the rapidly proliferating fraction of the colon were greater in rats fed the higher protein diet. However, the general architecture of small intestinal mucosa, including duodenum, jejunum and ileum, was not affected by protein malnutrition. Although the number of colonic cells was similar with fat refeeding, there were significantly fewer displaying the proliferating cell nuclear antigen in the colonic epithelium when rats were fed SC/PM compared with SC/SL. Therefore, changes in colonic mucosal proliferation were only seen with repletion by adequate protein and by SC/SL feeding.

Elevated plasma levels of hyaluronic acid indicate endothelial cell dysfunction in the initial stages of alcoholic liver disease in the rat.

BACKGROUND/AIMS: We used the intragastric feeding rat model for alcoholic liver disease to evaluate the relationship between morphologic and functional indicators of endothelial cell dysfunction. METHODS: Twelve groups of rats (4-5 rats/group) were fed the following diets: saturated fat and dextrose (SD), saturated fat and ethanol (SE), corn oil and dextrose (CD), corn oil and ethanol (CE). Four of the 12 groups were sacrificed at 2 weeks, four groups at 4 weeks and remaining four groups at 8 weeks. The following were evaluated at sacrifice: pathologic changes in the liver, endothelial cell proliferation using a monoclonal antibody to proliferating cell nuclear antigen, factor VIII-related antigen staining of endothelial cells in liver, plasma endotoxin, hyaluronan and prostaglandin F2 alpha. RESULTS: Only CE rats at 4 and 8 weeks showed pathologic changes. The plasma levels of HA were significantly higher in the CE groups compared to the other groups at all time intervals studied. In the CE rats, a significant correlation was obtained between plasma endotoxin and hyaluronan (r = 0.84, p < 0.01). Endotoxin levels also correlated significantly with the number of G1/S arrested hepatic sinusoidal endothelial cell (r = 0.61, p < 0.05). A role for prostaglandin F2 alpha, in causing endothelial dysfunction, was suggested by a significant correlation between plasma hyaluronan and prostaglandin F2 alpha levels (r = 0.95, p < 0.01). Positive factor VIII related antigen staining of hepatic endothelial cells was seen in rats with high plasma hyaluronan levels. CONCLUSION: We propose that endotoxin, mediating part of its effect through prostaglandin F2 alpha, plays a role in hepatic sinusoidal endothelial cell G1/S arrest. This morphologic change, associated with increased plasma hyaluronan levels, precedes capillarization in this model of alcoholic liver injury.

Role of transforming growth factor-[beta]1 in inhibiting endothelial cell proliferation in experimental alcoholic liver disease.

We used the intragastric feeding rat model for alcoholic liver disease to investigate the relationship between transforming growth factor (TGF)-beta 1 and inhibition of endothelial cell proliferation. Twelve groups of male Wistar rats (four to five rats per group) were fed ethanol or dextrose with either corn oil or saturated fat for 1-, 2-, and 4-week periods. All control animals were pair fed the same diets as ethanol-fed rats except that ethanol was isocalorically replaced by dextrose. In the ethanol-fed groups, nonparenchymal cells were isolated and TGF-beta 1 was measured in the nonparenchymal cell supernatant. Liver pathology and endothelial cell proliferation with an antibody to proliferating cell nuclear antigen were studied in all groups. Plasma TGF-beta 1 was measured in all rats. Pathological changes (fatty liver, necrosis, and inflammation) were observed only in the corn oil/ethanol-fed rats at 4 weeks. Significantly higher levels of TGF-beta 1 were seen in both plasma and nonparenchymal cell supernatant in rats fed corn oil and ethanol; plasma levels of TGF-beta 1 were not significantly different between the dextrose-fed controls and saturated fat/ethanol-fed rats. A significant inverse correlation (r = -0.89, P < 0.01) was seen between plasma TGF-beta 1 and the number of endothelial cells arrested at G1/S. Immunohistochemistry revealed the presence of TGF-beta 1 staining in interstitial macrophages only in rats fed corn oil and ethanol. The present study provides evidence for a role for TGF-beta 1 in inhibiting endothelial cell proliferation in experimental alcoholic liver disease. Arrest of endothelial cells may lead to their differentiation and/or to produce mediators that could stimulate other cells such as Ito cells. Sustained TGF-beta 1 may also lead to Ito cell production of extracellular matrix.

Nitric oxide production in experimental alcoholic liver disease in the rat: role in protection from injury.

BACKGROUND & AIMS: Regulation of blood flow and oxygen supply are important pathogenetic factors in alcoholic liver disease. Because nitric oxide may have an important role, its effects on alcoholic liver injury were investigated. METHODS: Rats were fed ethanol intragastrically with either saturated fat or corn oil. Spontaneous production of NO by liver nonparenchymal cells was compared in the two dietary groups. Two additional groups of rats fed corn oil and ethanol were treated with either an NO inhibitor (L-NAME) or supplemented with L-arginine. Liver pathology and plasma NO production were evaluated. RESULTS: In the corn oil and ethanol group, a progressive decrease in liver nonparenchymal cell NO production and increased plasma NO levels were associated with liver injury. Reduced nicotinamide adenine dinucleotide phosphate diaphorase staining showed increased centrilobular staining of hepatocytes in the corn oil and ethanol group and L-NAME-treated group. Moreover, L-NAME increased the severity, whereas L-arginine supplementation completely prevented liver injury. In the saturated fat and ethanol group, in which there was no liver injury, the levels of NO2- in nonparenchymal supernatant were 5-10-fold higher than in the corn oil and ethanol group. CONCLUSIONS: Decreased NO production by nonparenchymal cells may contribute to liver injury in ethanol-fed rats, and the compensatory increase in hepatocyte NO production may contribute to centrilobular liver injury.

Angiogenesis in invasive squamous cell carcinoma of the lip: tumor vascularity is not an indicator of metastatic risk.

BACKGROUND: Recent studies have shown that tumor growth beyond a certain size requires angiogenesis. Microvessel density has, moreover, correlated with metastatic risk in some tumors. Invasive squamous carcinoma (SCC) can develop in the epithelium of the lip and metastasize even when relatively small. This study investigates neovascularization and its relationship to metastatic risk in this tumor. METHODS: All 41 primary SCCs of the lip diagnosed at our institution from 1960 to 1991 were immunostained for factor VIII. Microvessel grade (Mv) from 1+ to 4+ and the average number of vessel profiles (TMvD) in the highest density 200 x (0.785 mm2) and 400 x (0.196 mm2) microscopic fields were determined. TMvDs were compared with those of adjacent non-tumor tissue (NTMvD). Normalized counts (TMvDns) were calculated as TMvD/NTMvD. TMvDs and TMvDns of metastasizing (N = 10) and non-metastasizing (N = 31) tumors were compared (student t-test). RESULTS: In all SCCs TMvDs exceeded NTMvDs (50 vs. 35 at 200 x, P = 0.0014, and 26 vs. 14 at 400 x, P < 0.0001). Metastasizing and non-metastasizing tumors did not, however, differ in Mv, TMvD, or TMvDn. CONCLUSIONS: Angiogenesis develops, but is not quantitatively related to metastatic risk, in primary invasive squamous cell carcinoma of the lip.