Tumour immunomodulation: mucins in resistance to initiation and maturation of immune response against tumours.

Mucins are high molecular weight glycoproteins designed for cellular protection and sensing the external environment. Aberrant glycosylation and altered mucin expression seen in cancers are implicated in mucin-dependent refraction to immunosurveilance and immunosuppressive induction around the tumour. Although mucins provide molecular targets for immune system's tumour recognition, their characteristics dictate that the nature of immune response required for recognition and lyses of mucin-expressing tumours needs to follow predominantly a MHC-unrestricted αß TCR-mediated effector cell response. Frequent loss of dendritic cells maturation and elimination of reactive lymphocytes altered adhesive and anti-adhesive properties of the mucins, promote tumour survival and escape from the immune response.

Autoimmune hemolytic anaemia in Hodgkin's lymphoma.

Autoimmune hemolytic anaemia is a rare presentation of Hodgkin's lymphoma though its association with Non- Hodgkin's lymphoma is well known. It is usually detected at the time of diagnosis when it accompanies Hodgkin's and rarely precedes it. It is a warm immune hemolytic anemia which is responsive to steroids and rituximab. We hereby report a case of advanced Hodgkin's disease who presented as AIHA.

A case of complete transection of right main bronchus in a child: Role of thoracoscopy and bronchoscopy.

Isolated tracheobronchial injuries are extremely rare in children and challenging due to life threatening complications. Blunt trauma to chest, especially in pediatric age group, is usually associated with multi-organ involvement and high mortality rate. These patients rarely reach a hospital. We have described here a case of complete transection of right main bronchus in a child, without hilar vascular injury, and its successful management, emphasizing the role of bronchoscopy and thoracoscopy.

Expression of Wnt 3a, ß-catenin, cyclin D1 and PCNA in mouse dentate gyrus subgranular zone (SGZ): a possible role of Wnt pathway in SGZ neural stem cell proliferation.

In mammalian dentate gyrus subgranular zone, the addition of new neurons throughout adulthood is a remarkable form of structural plasticity. Yet, the molecular controls over subgranular zone neural stem cell proliferation, survival, and differentiation are poorly understood. In this study we analysed the expression of Wnt 3a, ß-catenin, cyclin D1 and proliferating cell nuclear antigen in mouse subgranular zone to elucidate the involvement of Wnt pathway in subgranular zone neural stem cell proliferation. We performed immunohistochemistry and RT-PCR for the above molecules on adult and postnatal developing hippocampal tissues of mice, respectively. RT-PCR analysis showed a gradual increase in expression of mRNA of Wnt 3a, ß-catenin, cyclin D1 and proliferating cell nuclear antigen as the postnatal hippocampus developed, and immunohistochemical analysis showed a highly positive immunoreactive expression for Wnt 3a, ß-catenin, cyclin D1 and proliferating cell nuclear antigen in the subgranular zone cells. Together, our data suggested that the Wnt pathway is activated in subgranular zone and could play an important role in regulating subgranular zone neural stem cell proliferation in mouse hippocampus.

Vulval tuberculosis - an unusual presentation of disseminated tuberculosis.

Extrapulmonary involvement can occur in isolation or along with a pulmonary focus as in the case of patients with disseminated tuberculosis. Vulval TB is very rare and the presentation can be quite variable, and may be misdiagnosed as sexually transmitted disease. We herein report a young lady with disseminated TB presenting as Vulval TB.

Effect of the food flavour cinnamaldehyde on the antioxidant status of rat kidney.

Cinnamaldehyde, a food flavour, has a high potential for human consumption in India. In this study, we evaluated the effect of cinnamaldehyde on the antioxidant status of the rat kidney. Rats were given cinnamaldehyde orally by gavage at dose levels of 2.14, 6.96, 22.62 and 73.5 mg/kg body weight/day for the period of 10, 30 and 90 days. The non-enzymatic antioxidants ascorbic acid, alpha-tocopherol and reduced glutathione were decreased while the antioxidant enzymes, superoxide dismutase, glutathione peroxidase and glutathione-s-transferase were increased. Catalase was decreased and thiobarbituric acid-reactive substances were increased only in the kidney of rats treated with cinnamaldehyde at the dose level of 73.5 mg/kg body weight/day during an exposure period of 90 days and not in the kidney of other cinnamaldehyde-treated rat groups. Thus, cinnamaldehyde has an effect on the antioxidant status of rat kidney and its effect is time- and dose-dependent.

Expression of the Gas7 gene and Oct4 in embryonic stem cells of mice.

Oct4 is a stem cell expression marker, and persistence of its expression retains pluripotency in embryonic stem (ES) cells. Our results indicate a pattern of gradual decrease in Oct4 expression, which is prominent in the blastocyst and markedly reduced in the gastrula and neurula. The presence of POU transcription factor-like domain in Gas7 prompted us to look for its expression in the early embryonic cells. We have observed high expression of the Gas7 protein in blastocysts that gradually decreased in the neurula stages. The localization of Gas7 was initially seen throughout the blastocyst, but was later confined to dorsal ectodermal regions of the neurula, conforming with its role in neuronal differentiation. Our data reveal that Gas7 might play a role in cellular migration and cell protection in the ES cells of mouse embryo.

Effect of tincture of Crataegus on the LDL-receptor activity of hepatic plasma membrane of rats fed an atherogenic diet.

Tincture of Crataegus, (TCR), is a hypocholesterolemic and antiatherosclerotic drug made from berries of hawthorn, Crataegus oxyacantha. Its main constituents are flavonoids, triterpene saponins and a few cardioactive amines. TCR, when administered simultaneously to rats fed an atherogenic diet, significantly increased the binding of 125I-LDL to the liver plasma membranes, in vitro. Scatchard analysis of the specific binding data revealed that under the influence of TCR treatment the liver membranes bound to a greater number of 125I-LDL molecules indicating an enhancement in the LDL-receptor activity. TCR was also shown to increase bile acid excretion and to depress hepatic cholesterol synthesis in atherogenic diet fed rats. With these observations in view, the hypocholesterolemic action of TCR appears to be due to an upregulation of hepatic LDL-receptors resulting in greater influx of plasma cholesterol into the liver. TCR also prevents the accumulation of cholesterol in the liver by enhancing cholesterol degradation to bile acids and by simultaneously suppressing cholesterol biosynthesis. The various constituents of TCR may act synergistically to bring about the observed effects.

Enzyme-linked PNA lectin-binding assay of serum T-antigen in patients with SCC of the uterine cervix.

The expression of Thomsen-Friendenreich antigen (T-Ag) is associated with enhanced metastatic potential, poor prognosis and decreased survival rate in a variety of malignancies, and their detection and quantification can be used in serologic diagnosis. T-antigen expressions were measured by the enzyme-linked lectin assay (ELLA) with peanut agglutinin (PNA) in the sera of patients with squamous cell carcinoma (SCC) of the uterine cervix from 286 patients. This study has a sensitivity of 80%, specificity of 82% and a positive predictive value of 93%. Quantification of the T-antigen may provide useful biochemical indices for clinical assessment of the tumor spread and invasiveness of disease in SCC of the uterine cervix. Moreover, the ELLA assay is cheap, easy to perform and reproducible in the prognosis and diagnosis of SCC of the uterine cervix.

Serum alpha-N-acetylgalactosaminidase is associated with diagnosis/prognosis of patients with squamous cell carcinoma of the uterine cervix.

Serum alpha-N-acetylgalactosaminidase (NaGalase) is responsible for the deglycosylation of vitamin D(3)-binding protein (Gc protein). The deglycosylated Gc protein cannot be converted into major macrophage-activating factor (MAF), leading to immunosuppression. NaGalase is universally detected in a variety of cancer patients, but not in healthy individuals (Cancer Res. 56 (1997) 2827-2831). However, the diagnostic/prognostic utility of NaGalase in squamous cell carcinoma (SCC) of the uterine cervix is not known. To address this issue, the serum NaGalase was quantitatively determined in 210 patients with different stages of SCC of the uterine cervix. NaGalase levels were increased with the progression of the cancer. After radiotherapy, the increased levels returned toward or to normal levels in early stages (FIGO stage I-IIB) but not in advanced stages (FIGO stage III-IV). The present study revealed that the amount of NaGalase in the patient's bloodstream reflects the tumor burden and aggressiveness of the disease. We conclude that NaGalase is an independent predictor of diagnosis/prognosis in SCC of the uterine cervix, and therefore suggest that quantitative NaGalase alteration may reflect important differences in the immunological functions of these neoplasms.

Buthionine sulfoximine-induced glutathione depletion. Its effect on antioxidants, lipid peroxidation and calcium homeostasis in the lung.

The administration of buthionine sulfoximine (BSO), an irreversible inhibitor of gamma-glutamylcysteine synthetase, produces glutathione (GSH) depletion in tumors, making them sensitive to drugs and radiation. During the process, it also depletes GSH from normal tissues. Certain tumors require frequent doses of BSO for several days to produce GSH depletion. In this study, we determined that this chronic GSH-deficient condition lowers the antioxidant defense of the lung by diminishing the activities of superoxide dismutase, catalase, and glutathione peroxidase and the levels of ascorbic acid and alpha-tocopherol. Impaired antioxidant defense leads to enhanced lipid peroxidation, as indicated by increased levels of thiobarbituric acid reactive substances and conjugated dienes. The alteration of protein thiols by lipid peroxidation, is responsible for altered Ca2+ homeostasis, which, in turn, leads to cell injury. Cell injury was confirmed by elevated activities of angiotensin converting enzyme and lactate dehydrogenase, increased levels of protein and lactate, and histopathological changes.

Effect of eugenol on drug-metabolizing enzymes of carbon tetrachloride-intoxicated rat liver.

The chemoprotection extended by eugenol against carbon tetrachloride (CCl4) intoxication was established by studies on drug-metabolizing phase I and phase II enzymes. An overall decrease in drug-metabolizing enzymes, namely NADPH-cytochrome c reductase, NADH-cytochrome reductase, coumarin hydroxylase, 7-ethoxy coumarin-O-deethylase, UDP-glucuronyltransferase and glutathione-S-transferase, was observed with CCl4 intoxication, with a subsequent decrease in cytochrome P450 and cytochrome b5 content. CCl4 caused a significant decrease in microsomal phospholipids and the marker enzymes glucose-6-phosphatase and 5'-nucleotidase, and an increase in thiobarbituric acid reactive substances (TBARS). Simultaneous administration of eugenol with CCl4 inhibited the accumulation of TBARS and the decrease in the microsomal phospholipids and marker enzymes. Further, the chemical onslaught imposed by CCl4 on the drug-metabolizing system was removed successfully by eugenol. Eugenol appears to act as an in vivo antioxidant and as a better inducer of phase II enzymes than phase I enzymes. It is therefore suggested that eugenol could be an interesting basic structure for drug design.

Amiodarone--induced changes in surfactant phospholipids of rat lung.

Amiodarone HCl (AD) is a very effective antiarrhythmic drug, but its use is often associated with serious pulmonary complications. It is shown to induce lung phospholipidosis. Nevertheless, the effects of this drug on pulmonary surfactant which is composed of about 75% phospholipids and which prevents alveolar collapse is not known. Therefore, we have examined the effect of AD on the intra- and extracellular surfactant pools and on the levels of phosphatidylcholine (PC), the primary constituent of pulmonary surfactant. Male Wistar rats were fed AD (175 mg/kg) by oral gavage for three weeks. At the end of the experimental period, the rats were killed, the lungs removed and perfused, and surfactant isolated. Some lungs were prepared for ultrastructural examination. Phospholipid was assayed in the intra- and extracellular surfactant. Amiodarone produced a significant increase in both the intra- and extracellular surfactant phospholipid along with an appreciable change in the phospholipid profile. Also, the drug seemed to increase the number of lamellar inclusions in the surfactant producing type II alveolar cells. These data suggest that administration of AD leads to an increase in the lung surfactant phospholipid levels and lamellar bodies in alveolar type II cells.

Acute pulmonary toxicity of acrolein in rats--underlying mechanism.

Acute exposure of rats to acrolein (1 or 2 ppm) resulted in reduced levels of glutathione, ascorbic acid and alpha-tocopherol. The activities of catalase and glutathione peroxidase were reduced whereas an increase in the activities of superoxide dismutase was observed. This led to enhanced lipid peroxidation, which produced extensive lung damage as indicated by the elevated levels of the biochemical markers--angiotensin converting enzyme, lactate dehydrogenase, protein and lactate in the bronchoalveolar lavage.

Assessment of the no-observed-adverse-effect level (NOAEL) of gallic acid in mice.

Gallic acid is a naturally occurring plant phenol obtained by the hydrolysis of tannins and is known to show some pharmacological activities. The purpose of this paper is to establish the safety of gallic acid in mice. In this study, acute administration of gallic acid even at a dose as high as 5 g/kg body weight did not produce any signs of toxicity or mortality. In the subacute study, gallic acid at a dose of 1000 mg/kg body weight did not significantly alter the hematological parameters. Further, no appreciable change was noted in the various biochemical parameters such as SGOT and SGPT, as well as many serum constituents such as protein, cholesterol, urea and bilirubin. Therefore, from this study, it may be concluded that gallic acid is non-toxic up to a level of 5000 mg/kg body weight, when given orally. In addition, the subacute study indicated the absence of cumulative toxicity, as reflected by the non-significant alterations in the parameters investigated. The NOAEL was 5000 mg/kg body weight, the highest dose tested.

Lipid peroxidation as a possible secondary mechanism of sterigmatocystin toxicity.

Sterigmatocystin (Stg), a major secondary metabolite of Aspergillus versicolor and A. nidulans, is the precursor of aflatoxin B1. In this study, male albino rats were treated with Stg-contaminated diet for 30 days, resulting in reduced levels of glutathione, ascorbic acid, and alpha-tocopherol. The activity of catalase in liver was reduced, whereas an increase in the activities of superoxide dismutase and glutathione peroxidase was observed. The levels of cytochrome P450, cytochrome b5, cytochrome b5 reductase, cytochrome c reductase, hydroxyl radical, and hydrogen peroxide formation significantly increased in the Stg- treated rat liver microsomes. Hepatic parenchymal cell injury, necrosis, and Kupffer cells proliferation were noticed in histological sections of liver from animals treated with Stg. Overall results suggest that generation of free radicals imposes depletion of antioxidants. This led to enhanced lipid peroxidation. The observed elevation of hepatic thiobarbituric acid reactive substances appears to originate mainly from the damaged Kupffer cells. As a result, elevated levels of serum marker enzymes were also observed.

Lung injury by amiodarone, an antiarrhythmic drug, in male rats.

Administration of single dose (175 mg/kg body wt) of amiodarone dissolved in water through gavage for 3 weeks damaged the lung and changed the content of lung lavage. Activities of bronchoalveolar lavage (BAL) angiotensin converting enzyme (ACE) and lactate dehydrogenase (LDH) increased significantly. Also, the protein and lactate content of the lavage fluid increased significantly over the control. The drug also produced marked changes in morphology of the lung of experimental animals.

Effects of acrolein on rat liver antioxidant defense system.

Effect of acrolein (2.5 mg/kg body wt/day) on the rat liver antioxidant defense system was investigated. Following 45 days of acrolein exposure, the levels of glutathione, ascorbic acid and the activity of catalase were decreased whereas the activities of superoxide dismutase and glutathione peroxidase were increased. The increase in the level of thiobarbituric acid reactive substances in the acrolein treated rats showed oxidative damage. The results indicate that acrolein interferes with the antioxidant defense system of rat liver.

Effect of amiodarone, an antiarrhythmic drug, on serum and liver lipids and serum marker enzymes in rats.

Administration of amiodarone (AD) to rats leads to marked damage to liver, as evidenced by pathological changes and significant increases in activities of serum marker enzymes and levels of lipids like cholesterol and phospholipids with no alteration in the triglyceride levels. The risk factor, that is the total cholesterol/HDL cholesterol ratio, exhibited increase in the experimental animals, indicating that amiodarone treatment may lead to the development of coronary heart disease.

Methacrylonitrile induced oxidative stress in rat liver.

MeAN administration (40mg/kg body wt/day (i.e. 1/5 of LD50) resulted in increased levels of lipid peroxidation products, conjugated dienes and lipofuscin-like substances in rat liver. Significant decrease in GSH and a decreased activity of hepatic SOD, CAT and GPx were observed. There was also an increase in glutathione S-transferase and G6PD activities, decreased plasma ceruloplasmin and vitamin C implying oxidative stress caused by MeAN.