IFN-γ and other serum cytokines in head and neck squamous cell carcinomas.

SUMMARY: Altered immune responses have been reported in head and neck cancer, and some of these responses have been associated with poor clinical outcomes. A multiple-array technology platform was used to simultaneously evaluate the levels of 25 cytokines. Pre-treatment serum levels were evaluated in 31 HNSCC patients and 6 healthy controls. The levels of 8 cytokines, specifically IL-1ra, IL-2, IL-5, IL-6, IL-8, IL-17, IFN-γ and IP-10, were significantly higher in patients than in controls. Among cancer patients we observed lower levels of IFN-γ and IL-7 in cases with nodal metastases compared to those with cN0 disease. We observed increases in the levels of some serum cytokines in HNSCC patients, as well as reductions in selected cytokines associated with regional progression. These findings provide an intriguing perspective on the development and validation of novel markers for follow-up evaluations and predictions of regional spreading in HNSCC patients.

Diagnostic value of arterial blood gas lactate concentration in the different forms of mesenteric ischemia.

PURPOSE: The role of serum lactate measurement in patients with intestinal ischemia still remains unclear. The aim of this study was to prospectively evaluate the diagnostic performance of arterial blood gas lactate concentrations in the patients with acute mesenteric ischemia and its different forms. METHODS: All the patients reporting abdominal pain associated with risk factors for mesenteric ischemia underwent arterial blood gas and contrast enhanced abdominal computer tomography (CT). RESULTS: At CT, 201 patients (70.7%) showed a nonischemic disease (group 1) and 83 patients (29.2%) showed findings of mesenteric ischemia. Out of these, 35 patients (42.1%) showed bowel ischemia secondary to non vascular causes (group 2) and 48 (57.8%) had a vascular intestinal ischemia (group 3). Out of these, 20 showed small bowel arterial occlusion (group 3a), 13 a small bowel nonocclusive ischemia (group 3b), 7 a venous small bowel occlusion (group 3c) and 8 showed isolated colonic ischemia (group 3d). The median lactate serum level was significantly higher in patients with vascular ischemia if compared with patients with nonischemic disease and secondary mesenteric ischemia (p < 0.0001; Kruskal-Wallis test). The areas under ROC curves for the lactate serum levels in the groups 2, 3, 3a, 3b, 3c and 3d were, respectively, 0.61, 0.85, 0.93, 0.93, 0.68 and 0.67. CONCLUSIONS: Arterial blood gas lactate levels seem to show good diagnostic accuracy in diagnosing small bowel arterial and nonocclusive ischemia and poor accuracy in diagnosing secondary mesenteric ischemia, small bowel venous ischemia and ischemic colitis.

Implementing an ICT-Based Polypharmacy Management Program in Italy.

Although there is evidence of a growing awareness of the problem, no official policy statements or regulatory guidelines on polypharmacy have been released up to date by Italian Health Authorities. Medication review, application of appropriateness criteria and computerized prescription support systems are all possible approaches in order to improve the quality of prescribing in older persons. More focused training courses on multimorbidity and polytherapy management are encouraged. Furthermore a multidisciplinary approach integrating different health care professionals (physicians, pharmacists, and nurses) may positively impact on reducing the sense of fear related to discontinue or substitute drugs prescribed by others; the fragmentation of therapy among different specialists; reducing costs; and improving adverse drug reaction detection and reporting. Aiming at achieving the individualized pharmacotherapy, a multidisciplinary approach starting with identification of patients and risk for drug-related problems, followed by medication review overtime and use of inappropriateness criteria, supported by computerized systems has been proposed.

Increased platelet reactivity in Klinefelter men: something new to consider.

Patients with Klinefelter syndrome (KS) exhibit an increased cardiovascular risk, but underlying mechanisms are largely unknown. The present cross-sectional study has been conducted to evaluate platelet reactivity and the expression of platelet activation markers (8-iso-prostaglandin F2α[8-iso-PGF2α] and 11-dehydro-thromboxane-B2[11-dehydro-TXB2]) in KS patients and healthy controls. Twenty-three consecutive KS patients under testosterone replacement therapy have been included as case group and 46 age-matched healthy males recruited among hospital staff served as controls. Light transmission aggregometry was performed in both cases and controls and maximal platelet aggregation (max-A%) was defined as maximal light transmittance reached within 5 min after the addition of 0.2 or 0.4 mm arachidonic acid (AA). A ≥ 50% irreversible light transmittance (LT-50%) following platelet stimulation defined an adequate platelet aggregation and AC-50% was defined as the minimal agonist concentration needed to achieve LT-50%. The AC-50% was 0.26 mm AA for KS and 0.36 mm for controls (p < 0.001). Whereas AA (0.2 mm) induced LT-50% in 69.6% of KS and in 15.2% of controls (p < 0.001), the stimulation with AA (0.4 mm) determined LT-50% in all cases and controls. However, max-A% was higher in KS than in controls both after AA (0.2 mm) (65.61% vs. 46.30%, p = 0.002,) and after AA (0.4 mm) (96.43% vs. 81.04%, p < 0.001). 8-iso-PGF2α and 11-dehydro-TXB2 were higher in KS than in controls (446.54 pg/mg creatinine vs. 230.00 pg/mg creatinine, p < 0.001 and 1278.36 pg/mg creatinine vs. 595.08 pg/mg creatinine, p = 0.001, respectively) and AC-50% inversely correlated with 8-iso-PGF2α (ρ = -0.548, p < 0.001) and with 11-dehydro-TXB2 (ρ = -0.523, p < 0.001). In a linear regression model, KS independently predicted a lower AC-50% (ß = -0.597, p < 0.001) and higher levels of 8-iso-PGF2α (ß = 0.709, p < 0.001) and 11-dehydro-TXB2 (ß = 0.605, p < 0.001). In contrast, no correlation has been found between max-A%, testosterone and estradiol levels in KS. We observed increased platelet reactivity in KS. This might, at least in part, explain the increased thrombotic risk associated with this disease.

Novel path to IL-6 trans-signaling through thrombin-induced soluble IL-6 receptor release by platelets.

Interleukin (IL)-6 is a multifunctional cytokine with a critical role in inflammatory, immunoregulatory and haemopoietic responses. Its receptor consists of an ubiquitously expressed membrane transducing element (gp130) and of the specific element IL-6R-alpha (gp80), present only on hepatocytes and some leukocyte subsets. IL-6R-alpha also exists as soluble protein (sIL-6R) that, in the presence of IL-6, forms a complex able to bind gp130 and, thanks to the mechanism called trans-signaling, transduces IL-6 effect through tyrosine phosphorylation and activation of the signal transducer and transcription activator (STAT)-3. The aim of this study was to analyze the bidirectional relationships between platelet aggregation and IL-6-dependent effects. While platelets do not produce IL-6, we found that resting platelets express gp130, but not gp80, on their membranes. Upon activation by thrombin or calcium ionophore A23187, but not by ADP, the IL-6R-alpha is released in soluble form, while cangrelor, the specific inhibitor of P2Y12 receptor, can partially inhibit sIL-6R release. This sIL-6R is biologically active and, in the presence of IL-6, can trigger IL-6 trans-signaling, inducing an autocrine activation loop (as measured by an increase in gp80 and gp130 content) and STAT3 phosphorylation. On the other hand, IL-6 trans-signaling has no effect on platelet degranulation or aggregation by itself, nor on thrombin-induced platelet aggregation. Our data add an important piece to the puzzle of thrombosis and inflammation: in the presence of IL-6, which can be produced by stressed endothelial cells, the platelet-derived IL-6 trans-signaling could be crucial for the evolution of inflammation within a damaged vessel.

Differential anti-cancer effects of purified EPA and DHA and possible mechanisms involved.

As the concepts of pharmaconutrition are receiving increasing attention, it seems essential to clearly assess the effects of specific dietary compounds in specific groups of patients or clinical conditions. We are herein interested in better defining the differential anti-neoplastic effects of the two major n-3 long chain polyunsaturated fatty acids present in fish oil, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The efficiency of these fatty acids represents a subject of intense interest and debate, and whereas plenty of preclinical studies have strongly demonstrated their preventive and therapeutic effect in different kinds of cancers, the results of the epidemiologic studies are still controversial, and only a few trials have been performed. It has been reported that EPA and DHA may act either through the same or different mechanisms, thus suggesting that a differential efficacy could exist. At present, however, this point has not been clarified, although its better comprehension would allow a more proper and effective use of these fatty acids in the human interventional studies. In an attempt to elucidate this aspect we have herein analyzed the data obtained in the studies which have directly compared the antitumor effects of separate treatments with EPA or DHA. Most of the in vitro data indicate DHA as the more powerful antineoplastic agent. However, an equivalent efficiency of EPA and DHA is suggested by the few in vivo studies. Possible reasons for this discrepancy are discussed and pathways of cell growth that could be differentially influenced by EPA and DHA are described.

Zirconia toughened alumina (ZTA) powders: ultrastructural and histological analysis.

Ceramic materials, as Alumina and Zirconia, has made an improvement in the choice of new biomaterials for the load bearing application in dental and orthopaedic implants. These materials has shown mechanical resistance to high stress related to weight bearing and low debris in time. For this reason they are indicated on young patients implant, with high demanding activities and long life expectance. In literature however the risk of chronic inflammation due to chronic wear debris release and the possibility of carcinogenesis, is still to be definitively investigated. Another point to investigate is the acute reaction of the tissue in case of acute release of powders of these materials. The aim of this study was to investigate the possible local and systemic acute effects of ceramic precursors in form of powders of different size when released into articular joint. Powders of ZTA were implanted in the knee joint of twenty-four New Zealand white adult rabbits, that were sacrificed at 1,3,6, and 12 months. Radiographic, histological and immunoistochemestry analysis were conducted on periprosthetic tissue and peripheral organs, to verifying local host response and systemic toxic effects.

In vivo characterization of Zirconia Toughened Alumina material: a comparative animal study.

The development of a new chromia-doped Zirconia Toughened Alumina (ZTA) material was previously reported as displaying mechanical properties suitable for implants with load bearing applications, such as orthopaedic and dental implants. This type of biomaterial is expected to be in contact with living tissues for a long period of time and its long-term toxicity must be carefully evaluated. In this study the suitability of this ZTA material as a candidate biomaterial for orthopaedic implants and dental devices was further investigated in vivo in comparison to alumina and zirconia, which are currently used in orthopaedic and dental surgery. Cylinders of the materials were implanted in vivo in white rabbits, and local and systemic tissue reactions were analyzed at different time intervals after surgery. Radiologic examinations displayed the absence of radiolucence around cylinders and no signs of implant loosening up to twelve months. No tumours developed in the animals either locally (at the site of implantation), or systemically in the peripheral organs. The results obtained suggest that this new ZTA material does not display any long term pathogenic effect in vivo. These findings extend our previous observations on the biocompatibility and the absence of any long-term carcinogenic effect in vitro of this material which displays interesting properties for biomedical applications. In conclusion, we report the in vivo characterization of a new chromia-doped ZTA material and confirm its suitability as a candidate biomaterial for orthopaedic implants and dental devices since it does not give any local nor systemic toxicity even after a long period of time after implantation.

Inflammation and cancer: a multifaceted link.

STATE OF THE ART: Mounting evidence indicates a link between inflammation and cancer. However, the molecular mechanism(s) remains unclear. Indeed, although preclinical and clinical studies suggest that chronic inflammation can promote cancer development, the role(s) of inflammation in the process is likely very complex and far to be completely understood. Inflammation can promote all stages of tumor development through multiple mechanisms which include enhanced proliferation and resistance to apoptosis of initiated cells, induction of DNA mutations, promotion of angiogenesis, invasion and metastasis. On the other hand, components of tumor microenviroment, including tumor cells themselves, may promote an inflammatory state by producing inflammatory mediators. Moreover, while chronic inflammation might promote tumor formation, acute inflammation might well hamper the process and is indeed used therapeutically to inhibit tumor formation. CONCLUSIONS: The present review briefly highlights the relationship between inflammation and tumorigenesis and discusses the possibility to develop chemoprevention and/or therapeutical approaches targeting components of the inflammatory responses.

Expression of alpha-dystroglycan correlates with tumour grade and predicts survival in oral squamous cell carcinoma.

AIMS: Dystroglycan (DG) is a non-integrin adhesion molecule connecting the extracellular matrix to the actin cytoskeleton. Decreased expression of DG has been reported in several human cancers and related to tumour aggressiveness. METHODS: Expression of the alpha-DG subunit was evaluated by immunostaining in a series of oral squamous cell carcinoma (OSCC) and its relation with traditional prognostic indicators and with the clinical outcome of the patients was evaluated. RESULTS: Alpha-DG expression was easily detected in normal epithelium with a mean percentage of positive cells >80% but was undetectable in a significant fraction (59%) of OSCC. Loss of alpha-DG staining correlated with higher tumour grade (p = 0.04) and stage (p = 0.01), with nodal involvement (p = 0.001) and with an increased risk of recurrence (p = 0.002) and death (p = 0.004) in a univariate analysis, but it was not confirmed as an independent predictor of clinical outcome in a multivariate analysis. CONCLUSIONS: Loss of alpha-DG expression, which corresponds to loss of a functional DG complex, is a frequent event in human OSCC. Further studies are warranted on the role of this molecule in the entire multistep process of oral squamous tumorigenesis.

Post-translational modulation of CD133 expression during sodium butyrate-induced differentiation of HT29 human colon cancer cells: implications for its detection.

The CD133 molecule has been proposed as a surface marker of cancer stem cells in several human malignancies, including colon cancers. The function and the mechanisms regulating CD133 expression remain unknown. The HT29 human colon cancer cells undergo differentiation following treatment with various agents and represent a useful in vitro model of colon differentiation. This study evaluated the behavior of CD133 during sodium butyrate-induced differentiation of HT29 cells. Treatment with sodium butyrate induced a progressive decrease of CD133 expression, as assessed by flow cytometry using the AC133 monoclonal antibody. Indeed, expression of CD133, which was about 47% in untreated control cells, gradually decreased down to about 3% after 72 h in a time- and dose-dependent manner. No relationship was observed between CD133 protein evaluated by flow cytometry and mRNA expression level, and no changes were detected in the methylation status of the CD133 gene promoter during HT29 differentiation. Moreover, the expression of the CD133 protein, evaluated by Western blot analysis using a specific anti-CD133 antibody directed against the C-terminal intracytoplasmic region of human CD133 protein, did not correlate with flow cytometry results. Different results were also obtained using the two antibodies to analyze the expression of the CD133 molecule in human colon cancers. These findings demonstrate that membrane expression of the CD133 stem cell marker might undergo a complex regulation during differentiation of colon cells and suggest that HT29 cells are a useful in vitro model to study the mechanisms involved in this regulation which likely occurs at a post-transcriptional level.

Development of a new zirconia-toughened alumina: promising mechanical properties and absence of in vitro carcinogenicity.

High purity alumina as well as zirconia ceramics have been widely used as orthopaedic implant biomaterials and dental devices displaying optimal, but sometimes exclusive, mechanical properties. In order to combine the advantages of alumina and zirconia ceramic materials different types of composites have been developed in which either zirconia is dispersed in an alumina matrix or vice versa. Orthopaedic and dental implant biomaterials are expected to be in contact with living tissues for a long period of time and their long term toxicity must be carefully evaluated. In this study we report the development of a high performance chromia-doped zirconia toughened alumina (ZTA) material which displays promising mechanical properties in terms of hardness, strength and fracture toughness that make it suitable for prosthesis even for small joints. The long-term biocompatibility of this material was also evaluated, mainly in terms of DNA damage, mutagenicity and cancerogenetic potential in mammalian cells. The results obtained suggest that this new ZTA material does not display any longterm carcinogenic effect and it is suitable for biomedical applications from a cancerogenetic point of view. In conclusion, we report the development of a new chromia-doped ZTA material with interesting properties, both from a mechanical and a biocompatibility point of view which warrant further studies on its suitability as a candidate biomaterial for orthopaedic implants and dental devices.

Isolation and characterization of CD133+ cell population within human primary and metastatic colon cancer.

BACKGROUND: "Cancer stem cells" (CSC) have been identified as a minority of cancer cells responsible for tumor initiation, maintenance and spreading. Although a universal marker for CSC has not yet been identified, CD133 has been proposed as the hallmark of CSC in colon cancer. The aim of our study was to assess the presence of a CD133+ cell fraction in samples of colon cancer and liver metastasis from colon cancer and evaluate their potential as tumor-initiating cells. METHODS: Tissue samples from 17 colon cancers and 8 liver metastasis were fragmented and digested using collagenase. Cell suspensions were characterized by flow cytometry using anti-CD133, CD45 and CD31 antibodies. CD133+ cells were also isolated by magnetic cell sorting and their tumor-initiating potential was assessed versus the remaining CD133- fraction by soft-agar assay. RESULTS: Our results confirmed the existence of a subset of CD133+ tumor cells within human colon cancers. Interestingly, CD133+ cells were detectable in liver metastasis at a higher percentage when compared to primary tumors. Soft-agar assay showed that CD133+ cell fraction was able to induce larger and more numerous colonies than CD133-cells. CONCLUSION: Our findings data that the CD133+ colon cancer cells might play an important role in both primary tumors as well as in metastatic lesions thus warranting further studies on the role(s) of this subset of cells in the metastatic process.

Differential toxic effects of methyl tertiary butyl ether and tert-butanol on rat fibroblasts in vitro.

Methyl tertiary butyl ether (MTBE) is the most widely used motor vehicle fuel oxygenate since it reduces harmful emissions due to gasoline combustion. However, the significant increase in its use in recent years has raised new questions related to its potential toxicity. In fact, although available data are somehow conflicting, there is evidence that MTBE is a toxic substance that may have harmful effects on both animals and humans and an unresolved problem is the role played by MTBE metabolites, especially tertiary butyl alcohol (TBA), in determining toxic effects due to MTBE exposure. In this study, the toxic effects of MTBE have been analyzed on a normal diploid rat fibroblast cell line (Rat-1) and compared to the effects of TBA. The results obtained suggest that both MTBE and TBA inhibit cell growth in vitro but with different mechanisms in terms of effects on the cell cycle progression and on the modulation of cell cycle regulatory proteins. In fact, MTBE caused an accumulation of cells in the S-phase of the cell cycle, whereas TBA caused an accumulation in the G0/G1-phase with different effects on the expression of cyclin D1, p27Kip1, and p53. Moreover, both MTBE and TBA were also shown to induce DNA damage, as assessed in terms of oxidative DNA damage and nuclear DNA fragmentation, that appeared to be susceptible of repair by the cell DNA-repair machinery. In conclusion, these findings suggest that both MTBE and TBA can exert, by acting through different molecular mechanisms, important biological effects on fibroblasts in vitro. Further studies are warranted to shed light on the mechanisms responsible for the observed effects and on their potential significance for the in-vivo exposure.

Tumor cell proliferation and microsatellite alterations in human ameloblastoma.

Ameloblastoma is the most common odontogenic tumor. It can exhibit a variety of histological patterns, a great infiltrative potential and a high recurrence rate. Mutations in microsatellite sequences are a hallmark of neoplastic transformation but little is known about their role in ameloblastoma development. In this study DNA was extracted from laser-microdissected samples of 24 ameloblastomas and was analyzed for the status of 22 microsatellite loci. The occurrence and the pattern of microsatellite alterations, in form of loss or length variation, was evaluated and correlated with the Ki67 labeling index and with other clinicopathologic parameters. The prognostic significance of these alterations was also evaluated. High Ki67 expression was significantly associated with a shorter disease-free survival (p=0.003 by log-rank test). Alterations of at least one of the selected loci was observed in all (100%) the ameloblastomas analyzed with a mean of 4 altered microsatellites for each tumor. The microsatellites most frequently altered were D9S747 and D11S488 (42%). All the other loci analyzed were altered in less than 40% of cases and some of them (D3S1312, D3S1300, IFNA, D9S164, D13S176 and TP53) did not show alterations in any of the ameloblastomas analyzed. No relationship was observed between the occurrence of microsatellite alterations and other parameters, such as patients age and gender, tumor size, localization and histotype. The occurrence of microsatellite alterations was more frequent in tumors displaying a high Ki67 labeling index (p=0.03) and in a univariate analysis was predictor of an increased risk of disease recurrence (p=0.039 by log-rank test). These findings demonstrate that microsatellite alterations are frequent event in ameloblastomas. They also suggest that evaluation of tumor cells proliferative activity and microsatellite alterations may be helpful to stratify ameloblastomas prognostically and to predict the clinical behavior of these tumors.

Dystroglycan expression is reduced during prostate tumorigenesis and is regulated by androgens in prostate cancer cells.

Prostate cancer, the most frequently diagnosed cancer in Western men, can display a high variability in term of clinical aggressiveness and prognosis and none of the available markers is able to accurately predict its clinical course. Dystroglycan (DG), a non-integrin adhesion molecule, is a complex formed by two subunits, alpha- and beta-DG, which bind to extracellular matrix molecules and cytoskeleton, respectively. DG expression is frequently reduced in human cancers and has been related to tumor grade and aggressiveness. This study investigated the role of DG in human prostate tumorigenesis and its suitability as a prognostic marker. The expression level of extracellular alpha-DG subunit was frequently reduced in human prostate cancer cell lines and primary tumors and the percentage of positive tumor cells was significantly further decreased in vivo following androgen ablation therapy (median = 1%) compared to pre-treatment samples (median = 28%). A significant relationship was observed between alpha-DG staining on the post-treatment samples and tumor recurrence. A dose- and time-dependent decrease of DG expression also occurred in human prostate cancer cells following treatment with the anti-androgen flutamide. Stable expression of an exogenous DG cDNA in the LNCaP human prostate carcinoma cell line resulted in a marked inhibition of both anchorage-dependent and independent growth and of the in vivo tumorigenicity. These findings confirm and extend previous evidence that disturbances in the function of the DG complex might contribute to the definition of the malignant behavior of prostate cancer cells and suggest that androgens might regulate DG expression in these cells.

Methotrexate-added acrylic cement: biological and physical properties.

BACKGROUND: Previous reports have demonstrated the suitability of adding different chemotherapeutic drugs to acrylic cement for the treatment of bone metastases. The best results so far have been obtained with methotrexate (MTX) for which diffusion from the implanted cement has been demonstrated both in vitro and in vivo. In this study the suitability of adding MTX to acrylic cement as local adjuvant chemotherapy was investigated. METHODS: Using an in vitro model of human breast cancer cells we demonstrated that the drug is eluted in an active form able to exert a cytotoxic effect over a long period of time. The use of different concentrations of drug on the kinetic of elution and on the mechanical properties of cement was also evaluated. RESULTS: The results obtained suggest that the release of MTX is higher at the beginning and progressively decreases over time being affected by the concentration of drug used. Our results also demonstrated that the addition and the subsequent elution of MTX does not alter the compressive properties of the cement. CONCLUSION: These findings confirm the suitability of MTX-supplemented cement and support its use as an effective aid for the management of bone metastases requiring surgical curettage and acrylic cement implantation for structural support.

Magnesium and neoplasia: from carcinogenesis to tumor growth and progression or treatment.

Magnesium is involved in a wide range of biochemical reactions that are crucial to cell proliferation, differentiation, angiogenesis, and apoptosis. Changes in magnesium availability have been shown to influence biological responses of immuno-inflammatory cells. Equally plausible seems to be an involvement of magnesium in the multistep and interconnected processes that lead to tumor formation and development; however, the "how" and "when" of such an involvement remain to be defined. Here, we reviewed in vitro and in vivo data that indicated a role for magnesium in many biological and clinical aspects of cancer (from neoplastic transformation to tumor growth and progression or pharmacologic treatment). In adopting this approach we went through a full circle from molecular aspects to observational or epidemiological studies that could reconcile in a unifying picture the otherwise fragmentary or puzzling data currently available on the role of magnesium in cancer.

Serum magnesium profile in heroin addicts: according to psychiatric comorbidity.

Psychiatric comorbidity in heroin addiction can modify both the biological pattern and clinical course of this disorder. Because of the role of magnesium in neurotransmission and its specific patterns in some psychiatric conditions, such as depression and schizophrenia, we studied a sample of heroin dependent subjects, with and without psychiatric comorbidity. A sample of 162 drug addicts (123 men and 39 women, mean age 32.3 +/- 6.7) was diagnosed for the presence of psychiatric comorbidity with DSM IV criteria. They were subsequently divided in 4 subgroups: No comorbidity, Anxiety Disorders, Mood Disorders, Personality Disorders. Differences in serum magnesium level between the groups were analysed with the Anova method, with age as covariate. Results show that serum Mg++ levels are significantly higher in patients with heroin dependence and personality disorders compared to patients with depression comorbidity and without comorbidity. Psychiatric codiagnosis significantly modifies Mg++ levels in this drug dependent sample. Gender modifies Mg levels in no comorbid subjects so that females show significantly lower Mg++ levels compared to males. The presence of psychiatric comorbidity abates this difference.