Distribution of MUC1 in the normal human oral cavity is localized to the ducts of minor salivary glands

The change in expression of MUC1 from health to disease forms the basis of its use as a potential disease marker. Previous attempts at isolating MUC1 from normal, healthy human oral mucosa have, however, drawn conflicting conclusions as to its presence. Furthermore, when MUC1 was detected in the oral glycocalyx, it was not clear which cells were synthesising it. We examined human oral glycocalyx using pooled buccal smears from 50 normal individuals. Following isopycnic density centrifugation and membrane extraction with octyl glucoside and saponin, MUC1 was detected with the polyclonal antibody CT1. Immunohistochemistry using antibodies CT1 and BC2 was performed on sections from eight labial, seven palatal, four buccal, three retromolar pad, three dorsum of tongue and two ventral surface of tongue biopsies. In-situ hybridisation using MUC1 and cytoplasmic tail oligoprobes on sections from four palatal, seven labial and two retromolar pad biopsies was also carried out. MUC1 mRNA could only be detected in the minor salivary mucous glands. MUC1 has already been identified in the ducts of normal parotid and submandibular gland, and our findings demonstrate a similar distribution in minor salivary glands. We conclude that when present in the normal oral glycocalyx, the only oral source of MUC1 is from cell membranes of the minor salivary glands.

An application of the thresholds of change model to the analysis of mental health data

The threshold of change model (TCM) is a statistical technique for analyzing ordered stages of change variables. TCM focuses on the thresholds that separate the ordered stages, and the effects of explanatory variables are evaluated in terms of raising or lowering the thresholds. TCM also allows the explanatory variables to exert differential influence on each threshold. In this paper, we use TCM to analyze the data from a clinical trial that compared assertive community treatment (ACT) with standard case management (SCM) for patients with co-occurring severe mental illness and substance use disorder. Endpoint data (36-month follow up) were used for this analysis. The response variable is the recoded Substance Abuse Treatment Scale with three ordered levels (engagement/persuasion, active treatment, and recovery/relapse prevention), and hence two thresholds. The explanatory variables are gender and group (ACT vs. SCM). The results indicate that gender exerts constant and significant effects on both thresholds. The group effect is somewhat mixed: ACT lowers the first threshold (active treatment), but raises the second threshold (recovery/relapse prevention).

Microsatellite instability in squamous cell carcinoma of head and neck from the Indian patient population

Genomic instability in simple repeated sequences has been observed in several human cancers. We have analyzed 50 squamous cell carcinomas of the head and neck (SCCHN) and 5 pre-malignant severe dysplastic tissues from Indian patient populations for microsatellite instability in 18 different loci spread over eight different chromosomes. Among the tumors analyzed, 45% exhibited instability at two or more loci, and 15% exhibited instability at 40% of the markers tested. Similar analysis of SCCHN tumors from other populations (British, American and French) showed much less frequency of instability. SCCHN tumors in the present study did not show any instability in the mononucleotide repeat sequences. There is also a clear distinction in the nature of the instability in these tumors in comparison with colorectal tumors. These results suggest that the underlying mechanism generating this type of instability is different from those reported for colorectal tumors.

Functional domains of yeast plasmid-encoded Rep proteins

Both of the Saccharomyces cerevisiae 2 microm circle-encoded Rep1 and Rep2 proteins are required for efficient distribution of the plasmid to daughter cells during cellular division. In this study two-hybrid and in vitro protein interaction assays demonstrate that the first 129 amino acids of Rep1 are sufficient for self-association and for interaction with Rep2. Deletion of the first 76 amino acids of Rep1 abolished the Rep1-Rep2 interaction but still allowed some self-association, suggesting that different but overlapping domains specify these interactions. Amino- or carboxy-terminally truncated Rep1 fusion proteins were unable to complement defective segregation of a 2 microm-based stability vector with rep1 deleted, supporting the idea of the requirement of Rep protein interaction for plasmid segregation but indicating a separate required function for the carboxy-terminal portion of Rep1. The results of in vitro baiting assays suggest that Rep2 contains two nonoverlapping domains, both of which are capable of mediating Rep2 self-association. The amino-terminal domain interacts with Rep1, while the carboxy-terminal domain was shown by Southwestern analysis to have DNA-binding activity. The overlapping Rep1 and Rep2 interaction domains in Rep1, and the ability of Rep2 to interact with Rep1, Rep2, and DNA, suggest a model in which the Rep proteins polymerize along the 2 microm circle plasmid stability locus, forming a structure that mediates plasmid segregation. In this model, competition between Rep1 and Rep2 for association with Rep1 determines the formation or disassembly of the segregation complex.

Modulation of DMBA induced genotoxicity in bone marrow by quercetin during skin carcinogenesis

Effect of quercetin was studied on DMBA induced skin carcinogenesis in young adult Swiss albino mice. Quercetin was administered continuously with the diet (2%) for four weeks and chromosomal aberration, a predictor of future cancer risk, studied in the bone marrow cells at different time intervals. Significant reduction of chromosomal aberration was observed in bone marrow after four weeks (P< 0.02). The reduction was first evident after 96 hrs though it was not significant at this stage. Significant decrease occurred from the 21st day onward when quercetin was given in concomitance with 7,12-dimethylbenz[a]anthracene (DMBA) indicating a definite protective effect of quercetin on chromosomal aberration.

The relationship of aging and dysthymia in primary care

The authors compared symptomatic and functional characteristics between older (age > or =60; n=91) and younger (age 18-59; n=125) primary care patients with dysthymia. Three of six significantly different depression symptoms were of moderate-to-large effect size, with the older group having a lower proportion reporting the symptom. The older group had a worse physical health function score but a better mental health function score. There appears to be a core of symptoms and functional impairment that generalizes across the age span. There are also significant age differences. Growing older appears to have an impact on the nature of what it means to have dysthymia.

Mechanism of neurofibrillary degeneration and pharmacologic therapeutic approach

Neurofibrillary degeneration is a key histopathological brain lesion of Alzheimer disease (AD) and related neurodegenerative disorders such as frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17), commonly referred to as tauopathies. Microtubule associated protein (MAP) tau, which is a major MAP of a normal mature neuron is abnormally hyperphosphorylated in tauopathies and is the major protein subunit of paired helical filaments (PHF)/straight filaments (SF) which accumulate in the soma (as neurofibrillary tangles) and dystrophic neurites (as neuropil threads and as dystrophic neurites surrounding the beta-amyloid core in neuritic plaques in AD) of the affected neurons. Unlike normal tau which stimulates assembly and stabilizes microtubules, the abnormally hyperphosphorylated tau inhibits assembly and disrupts microtubules. The abnormally hyperphosphorylated tau competes with tubulin/microtubules in associating with normal tau, MAP1 and MAP2. This sequestration of normal MAPs by the abnormal tau results in the breakdown of the microtubules. The association of the abnormal tau with normal tau and not with MAP1 or MAP2 results in the formation of tangles of tau filaments. All these toxic properties of the abnormally hyperphosphorylated tau are eliminated by its enzymatic dephosphorylation. Activities of phosphoseryl/phosphothreonyl protein phosphatases (PP)-2A and PP-1 which can dephosphorylate the abnormal tau to a normal-like state are compromised in AD brain. Dephosphorylation by PP-2A and PP-2B and to a lesser extent by PP-1 restores the normal microtubule assembly promoting activity in AD P-tau in vitro. Neurofibrillary tangles of PHF isolated from AD brain are also dissociated on in vitro dephosphorylation with PP-2A, and the tau released by this treatment can stimulate microtubule assembly. Thus, it appears that the abnormal hyperphosphorylation of tau leads to neurodegeneration through breakdown of the microtubule network and that the abnormal tau on association with normal tau forms neurofibrillary tangles of tau filaments i.e. PHF/SF. Increase in tau phosphatase activity is a promising approach to inhibit neurofibrillary degeneration and thereby the diseases characterized by this lesion.

Family treatment and medication dosage reduction in schizophrenia: effects on patient social functioning, family attitudes, and burden

The effects of 2 family intervention programs (supportive family management [SFM], including monthly support groups for 2 years; or applied family management [AFM], including 1 year of behavioral family therapy plus support groups for 2 years), and 3 different neuroleptic dosage strategies (standard, low, targeted) on social functioning of patients with schizophrenia. their relatives' attitudes, and family burden were examined. AFM was associated with lower rejecting attitudes by relatives toward patients and less friction in the family perceived by patients. Patients in both AFM and SFM improved in social functioning but did not differ, whereas family burden was unchanged. Medication strategy had few effects, nor did it interact with family intervention. The addition of time-limited behavioral family therapy to monthly support groups improved family atmosphere, but did not influence patient social functioning or family burden.

Engineering aspects of enzymatic signal transduction: photoreceptors in the retina

Identifying the basic module of enzymatic amplification as an irreversible cycle of messenger activation/deactivation by a "push-pull" pair of opposing enzymes, we analyze it in terms of gain, bandwidth, noise, and power consumption. The enzymatic signal transduction cascade is viewed as an information channel, the design of which is governed by the statistical properties of the input and the noise and dynamic range constraints of the output. With the example of vertebrate phototransduction cascade we demonstrate that all of the relevant engineering parameters are controlled by enzyme concentrations and, from functional considerations, derive bounds on the required protein numbers. Conversely, the ability of enzymatic networks to change their response characteristics by varying only the abundance of different enzymes illustrates how functional diversity may be built from nearly conserved molecular components.

Palatogenesis and potential mechanisms for clefting

This review concentrates on mechanisms of palatogenesis. This includes theories of shelf elevation, the role of matrix and identification of molecules and growth factors, which have key roles. The areas where failure to develop could potentially lead to clefting are highlighted. A key part of shelf fusion is the breakdown of the medial edge epithelium, a process that is probably dependent on enzymes involved in matrix turnover. There is good evidence that the matrix metalloproteinases may provide a common link to the multiple genetic and environmental factors that are known to cause clefting.

Influences of graded dose of melatonin on the levels of blood glucose and adrenal catecholamines in male roseringed parakeets (Psittacula krameri ) under different photoperiods

Effects of daily evening (just before the onset of darkness in a 24 h light dark cycle) administration of graded doses (25, 50, or 100 microg/100 g body wt./day for 30 days) of melatonin on the concentrations of blood glucose and adrenal catecholamines were studied in sexually active male roseringed parakeets under natural (NP; approximately 12L: 12D) and artificial long (LP; 16L: 8D) and short (SP; 8L: 16D) photoperiods. Blood samples and adrenal glands were collected from each bird during the mid-day on the following day of the last treatment. The concentrations of glucose in blood and epinephrine (E) and norepinephrine (NE) in the adrenals were measured. The results of the study indicated that exogenous melatonin induces hypo- or hyperglycemia depending on the dose of hormone administered as well as to the length of photoperiod to which birds were exposed. The levels of E and NE in the adrenals were shown also to vary in relation to photoperiod and the dose of melatonin administered. But the nature of the influence of melatonin becomes different under altered photoperiodic conditions. It appears that short photoperiods are more effective than long photoperiods as a modulator of glycemic and adrenal catecholaminergic responses to exogenous melatonin. A statistically significant correlation between the levels of blood glucose and that of E and NE in the adrenals was found in the control birds, but not in the melatonin treated birds. The results suggested that the responses of blood glucose and adrenal catecholamines to the treatment with melatonin in the roseringed parakeets may not be dependent on each other.

Gastric stromal tumours: a practical approach

Recent findings on the pathological diversity of gastric stromal tumours and their unpredictable behaviour prompted us to review our series of 16 patients who had undergone surgery for these tumours from 1991 to 1998. There were 13 benign and 3 malignant lesions. The majority of patients presented with either upper gastrointestinal bleeding or anaemia alone (12 of 16). Endoscopy was an extremely useful diagnostic tool, revealing the lesion as an intraluminal protuberant tumour with or without ulcer in 10 cases and as an ulcer alone in 4 cases, and in 1 case features suggesting an extrinsic mass. All the patients in the series underwent surgery. We used staplers (AutosutureR TA 55) to excise the tumours in 7 cases, all of which on histological examination were benign with clear resection margins. Gastric resections were performed in 5 cases for either large tumours or those situated at the fundus or antrum and local excision of the remaining 4. The mean follow-up of these patients was 24 months. Two patients with malignant lesions died of irresectable recurrences, one 2 months and one 18 months after surgery. There have been no recurrences in the tumours diagnosed as benign on histology. Tumour size, position and the ability to apply the stapler leaving adequate margin below the tumour should be the determinants of extent and type of excision. Reliable determinants of behaviour are tumour size, grade and mitotic index.

Influence of photoperiods on glycemic and adrenal catecholaminergic responses to melatonin administrations in adult male roseringed parakeets, Psittacula krameri Neumann

Effects of daily (one hour prior to onset of darkness) injection of melatonin (25 micrograms/100 g body wt. for 30 days) on concentrations of blood glucose and adrenal catecholamines were studied in adult male roseringed parakeets, P. krameri under both natural (NP; about 12L:12D) and artificial long (LP; 16L:8D; lights were available in between 0600 and 2200 hrs) or short (SP; 8L:16D; lights were available between 0600 and 1400 hrs) photoperiodic conditions. The results indicate that neither LP, nor SP as such exerts any significant effect on blood glucose titre of control (vehicle of hormone administered) birds. Treatment with melatonin, however, induced hyperglycemia in both NP and LP bird groups, but hypoglycemia in SP birds. Unlike glycemic levels, amount of epinephrine (E) and norepinephrine (NE) in adrenals of control birds exhibited significant changes under altered photoperiods. A decrease in E and an increase in NE were noted in adrenals of both LP and SP birds. Exogenous melatonin in NP birds also caused a decrease in E and concomittant rise in NE levels. On the other hand, treatment of melatonin in both LP and SP bird groups resulted in an increase in the quantity of both E and NE compared to respective values in adrenals of melatonin injected NP birds. However, relative to the amount of E and NE in adrenals of placebo treated LP and SP birds, significant effect of melatonin treatment was observed only in SP birds. The results suggest that influences of exogenous melatonin on the levels of both blood glucose and adrenal catecholamines are largely modulated by short rather than long photoperiods.

Treatment of dysthymia and minor depression in primary care: A randomized controlled trial in older adults

CONTEXT

Insufficient evidence exists for recommendation of specific effective treatments for older primary care patients with minor depression or dysthymia.

OBJECTIVE

To compare the effectiveness of pharmacotherapy and psychotherapy in primary care settings among older persons with minor depression or dysthymia.

DESIGN

Randomized, placebo-controlled trial (November 1995-August 1998).

SETTING

Four geographically and clinically diverse primary care practices.

PARTICIPANTS

A total of 415 primary care patients (mean age, 71 years) with minor depression (n = 204) or dysthymia (n = 211) and a Hamilton Depression Rating Scale (HDRS) score of at least 10 were randomized; 311 (74.9%) completed all study visits.

INTERVENTIONS

Patients were randomly assigned to receive paroxetine (n = 137) or placebo (n = 140), starting at 10 mg/d and titrated to a maximum of 40 mg/d, or problem-solving treatment-primary care (PST-PC; n = 138). For the paroxetine and placebo groups, the 6 visits over 11 weeks included general support and symptom and adverse effects monitoring; for the PST-PC group, visits were for psychotherapy.

MAIN OUTCOME MEASURES

Depressive symptoms, by the 20-item Hopkins Symptom Checklist Depression Scale (HSCL-D-20) and the HDRS; and functional status, by the Medical Outcomes Study Short-Form 36 (SF-36) physical and mental components.

RESULTS

Paroxetine patients showed greater (difference in mean [SE] 11-week change in HSCL-D-20 scores, 0.21 [0. 07]; P =.004) symptom resolution than placebo patients. Patients treated with PST-PC did not show more improvement than placebo (difference in mean [SE] change in HSCL-D-20 scores, 0.11 [0.13]; P =.13), but their symptoms improved more rapidly than those of placebo patients during the latter treatment weeks (P =.01). For dysthymia, paroxetine improved mental health functioning vs placebo among patients whose baseline functioning was high (difference in mean [SE] change in SF-36 mental component scores, 5.8 [2.02]; P =. 01) or intermediate (difference in mean [SE] change in SF-36 mental component scores, 4.4 [1.74]; P =.03). Mental health functioning in dysthymia patients was not significantly improved by PST-PC compared with placebo (P>/=.12 for low-, intermediate-, and high-functioning groups). For minor depression, both paroxetine and PST-PC improved mental health functioning in patients in the lowest tertile of baseline functioning (difference vs placebo in mean [SE] change in SF-36 mental component scores, 4.7 [2.03] for those taking paroxetine; 4.7 [1.96] for the PST-PC treatment; P =.02 vs placebo).

CONCLUSIONS

Paroxetine showed moderate benefit for depressive symptoms and mental health function in elderly patients with dysthymia and more severely impaired elderly patients with minor depression. The benefits of PST-PC were smaller, had slower onset, and were more subject to site differences than those of paroxetine.

Optimal tests for no contamination in reliability models

Inferences on mixtures of probability distributions, in general, and of life distributions, in particular, are receiving considerable importance in recent years. The likelihood ratio procedure of testing for the null hypothesis of no contamination is often very cumbersome and lacks its usual asymptotic properties. Recently, SenGupta (1991) has introduced the notion of an 'L-optimal' test for such testing problems. The idea is to recast the original several parametric hypotheses representation of the null hypothesis in terms of only a single hypothesis involving an appropriately chosen parametric function. This approach is shown to be both mathematically elegant and operationally simple for a quite general class of mixture distributions which contains, in particular, all mixtures of the one-parameter exponential family and also a very rich subclass of mixtures useful in life-testing and reliability analysis. It is also illustrated through two examples--one based on real-life data and the other on a simulated sample.

PTSD and utilization of medical treatment services among male Vietnam veterans

This study investigated the effect of posttraumatic stress disorder (PTSD) on help-seeking for physical problems. Merging two large data sets resulted in a sample of 1773 male Vietnam veterans from white, black, Hispanic, Native Hawaiian, and Japanese American ethnic groups. Predictors of utilization included PTSD, other axis I disorders, and substance abuse. In analyses that adjusted only for age, PTSD was related to greater utilization of recent and lifetime VA medical services, and with recent inpatient care from all sources. Further analysis showed that the increased utilization associated with PTSD was not merely due to the high comorbidity between PTSD and other axis I disorders. The uniqueness of the association between PTSD and medical utilization is discussed in terms of somatization and physical illness.

Improving the precision of primary care physician self-report of antidepressant prescribing

BACKGROUND

Methods to select physicians most likely to benefit from educational interventions to improve the outcome of depression have not been adequately developed.

OBJECTIVE

The purpose of this study was to identify a combination of primary care provider (PCP) self-report questions to improve the precision of PCP estimates of actual antidepressant prescribing as a potential tool for PCP selection.

METHODS

The total number of new and refill antidepressant prescriptions written by 124 PCPs and actually filled at pharmacies over a 2-year period were matched with telephone survey results of these PCPs completed before the 2-year period. Multiple regression techniques were used to identify a set of variables that improved upon PCPs' self-report of prescriptions.

RESULTS

The mean for PCP-reported antidepressant prescriptions written in the last week was 7.8 (+/-11.2). The average weekly prescriptions actually filled was 6.72 (+/-5.65). Most survey variables were significantly correlated with antidepressant prescriptions. The final model included 6 variables that explained 52% of the variance in prescriptions. In addition to PCP-reported number of antidepressants prescribed, average number of primary care patients seen per week and number of patients covered by managed care were directly related to the volume of prescriptions. PCP age, percentage of patients referred immediately without treatment, and mental health services being too far away were inversely related.

CONCLUSIONS

PCP self-reports on antidepressant prescribing are reasonably accurate proxies of actual prescribing. The precision of estimates of actual prescribing can be improved by considering practice structural and financial characteristics.

Pre-clinical toxicity evaluation of leaf-stalk extractive of Piper betle Linn. in rodents

Studies on pre-clinical toxicity were undertaken to determine the haematological and biochemical changes after administration of alcoholic extract of leaf-stalk of P. betle in rats and mice. Acute and chronic toxicity experiments were performed on mice and rats according to WHO protocol. Different doses of plant extractive were administered for toxicity studies on short and long term basis. Haematological, biochemical profiles and enzymatic studies (transaminases and phosphatases) indicated that the drug (plant extractive) was devoid of toxicity.

Predictors and outcomes of posttraumatic stress disorder in World War II veterans exposed to mustard gas

Current posttraumatic stress disorder (PTSD) associated with participation in secret military tests of mustard gas during World War II was assessed in 363 male military veterans who were randomly sampled from a registry developed by the Department of Veterans Affairs. Current prevalence was 32% for full PTSD and 10% for partial PTSD. Prevalence of PTSD varied as a function of risk and protective factors, including volunteering, physical symptoms during the tests, and prohibited disclosure. Prediction of partial PTSD was weaker than prediction of full PTSD. Veterans with full PTSD reported poorer physical health, a higher likelihood of several chronic illnesses and health-related disability, greater functional impairment, and higher likelihood of health care use than those with no PTSD. Veterans with partial PTSD also had poorer outcomes than did veterans with no PTSD in a subset of these domains. There is discussion of the traumatic elements of experimental mustard gas exposure, vulnerability to PTSD, and the relevance of these findings to understanding the broad range of outcomes associated with PTSD.

The effects of dental wear on third molar eruption and on the curve of Spee in human archaeological dentitions

The abrasiveness of food is a key determinant in the rate of physiological attrition (dental wear) in humans. With increasing food processing through time, the rate of physiological dental wear in human teeth has decreased markedly. Many consider such wear to be beneficial to oral health and that insufficient wear may result in impaction of the third molars. If enhanced extraoral food processing provides an evolutionary advantage, then it is possible that agenesis of the redundant third molar may follow. One of the aims here was to examine impaction and agenesis of the third molars in four populations of varying antiquity and hence varying dental-wear rates. Paradoxically, whilst there is a decrease in the rate of dental wear with modernity, there is also an increasing prevalence of advanced dental wear due to prolongation of the lifespan of the human dentition. As the effect of dental wear on the curve of Spee was unknown, a second aim was to examine it in an archaeological population with a high rate of dental wear. The results showed an increase in non-eruption and impaction of the third molars with modernity, but did not demonstrate a significant increase in the rate of agenesis. The time period over which impaction and agenesis could be discerned was of the order of 600 years and this may not be sufficient to observe adaptive changes at the genetic level in humans. In molar teeth there was no clear indication of maintenance of the curve of Spee with dental wear. This has potential implications on the design of prostheses for the worn dentition.

Difficulties in estimating age using root dentine translucency in human teeth of varying antiquity

Estimation of age at death is an essential part of reconstructing information from skeletal material. This becomes more difficult after development has ceased and following taphonomic alteration in archaeological material. Most biological markers of age do not record the chronological age (calendar age), but the biological or physiological age of the individual. Of the age-related changes in the mature dentition of modern samples, the extent of root dentine translucency (RDT) has been shown to correlate closely with chronological age. A protocol for measurement of RDT was established and applied to modern and archaeological teeth of known age (Spitalfields sample). Percentage length of RDT in sectioned teeth was found to correlate well with chronological age in the modern sample but not in the archaeological sample. The majority of the archaeological sample was affected by a morphological change creating a "chalky" appearance to the dentine. Removal of the obviously affected teeth did not improve the correlation coefficients to any useful degree. "Chalky" dentine appeared, under the light microscope, to be composed of large fenestrations, islands of mineralized tissue and masses of filiform structures that appeared to be following the path of the dentinal tubules in their invasion of the peripheral dentine. The filiform structures are consistent in their appearance with a previously reported tunnelling mycelium and impart such an effect on RDT that it cannot readily be used for age estimation in affected teeth.

Characterization of minor site probes for human serum albumin by high-performance affinity chromatography

This study used high-performance affinity chromatography (HPAC) and immobilized human serum albumin (HSA) columns to examine the specificity and cross-reactivity of various compounds that have been proposed as markers for the minor binding sites of HSA. These agents included acetyldigitoxin and digitoxin as probes for the digitoxin site, phenol red as a probe for the bilirubin site, and cisor trans-clomiphene as markers for the tamoxifen site. None of these probes showed any significant binding at HSA's indole-benzodiazepine site. However, phenol red did bind at the warfarin-azapropazone site of HSA, and cis/trans-clomiphene gave positive allosteric effects caused by the binding of warfarin to HSA. Digitoxin and acetyldigitoxin were found to bind to a common, unique region on HSA; cis- and trans-clomiphene also appeared to interact at a unique site, although trans-clomiphene displayed additional direct competition with phenol red. From these results it was possible to develop a model that described the general relationship between these binding regions on HSA. This information should be useful in future studies that employ HPAC for characterizing the binding of HSA to other drugs or clinical agents.

The anti-carcinogenic role of lycopene, abundantly present in tomato

Among the many carotenoids present in nature, lycopene has been of special interest and has received attention in recent times due to its suggestive association in reducing risk for cancer at many sites including breast, prostate and pancreas. Several studies have attempted to determine the bioactive levels of this carotenoid in human tissues and the influence of plant food and cancer on carotenoid levels. Experimental studies have also implicated the protective role of lycopene during carcinogenesis. These observations should justify further exploration and evaluation of the biological function of lycopene alone or in combination with other chemical compounds present in tomato fruit for their use in cancer prevention.