Chara Spiliopoulou

Zinc and human health: an update

The importance of micronutrients in health and nutrition is undisputable, and among them, zinc is an essential element whose significance to health is increasingly appreciated and whose deficiency may play an important role in the appearance of diseases. Zinc is one of the most important trace elements in the organism, with three major biological roles, as catalyst, structural, and regulatory ion. Zinc-binding motifs are found in many proteins encoded by the human genome physiologically, and free zinc is mainly regulated at the single-cell level. Zinc has critical effect in homeostasis, in immune function, in oxidative stress, in apoptosis, and in aging, and significant disorders of great public health interest are associated with zinc deficiency. In many chronic diseases, including atherosclerosis, several malignancies, neurological disorders, autoimmune diseases, aging, age-related degenerative diseases, and Wilson’s disease, the concurrent zinc deficiency may complicate the clinical features, affect adversely immunological status, increase oxidative stress, and lead to the generation of inflammatory cytokines. In these diseases, oxidative stress and chronic inflammation may play important causative roles. It is therefore important that status of zinc is assessed in any case and zinc deficiency is corrected, since the unique properties of zinc may have significant therapeutic benefits in these diseases. In the present paper, we review the zinc as a multipurpose trace element, its biological role in homeostasis, proliferation and apoptosis and its role in immunity and in chronic diseases, such as cancer, diabetes, depression, Wilson’s disease, Alzheimer’s disease, and other age-related diseases.

Zinc: a multipurpose trace element

Zinc (Zn) is one of the most important trace elements in the body and it is essential as a catalytic, structural and regulatory ion. It is involved in homeostasis, in immune responses, in oxidative stress, in apoptosis and in ageing. Zinc-binding proteins (metallothioneins, MTs), are protective in situations of stress and in situations of exposure to toxic metals, infections and low Zn nutrition. Metallothioneins play a key role in Zn-related cell homeostasis due to their high affinity for Zn, which is in turn relevant against oxidative stress and immune responses, including natural killer (NK) cell activity and ageing, since NK activity and Zn ion bioavailability decrease in ageing. Physiological supplementation of Zn in ageing and in age-related degenerative diseases corrects immune defects, reduces infection relapse and prevents ageing. Zinc is not stored in the body and excess intakes result in reduced absorption and increased excretion. Nevertheless, there are cases of acute and chronic Zn poisoning.

Genotype-phenotype assessment in autosomal recessive arrhythmogenic right ventricular cardiomyopathy (Naxos disease) caused by a deletion in plakoglobin.

OBJECTIVES The purpose of this study was to examine the genotype-phenotype relation with respect to penetrance, age and severity of expression, disease progression and prognosis in a recessively inherited arrhythmogenic right ventricular cardiomyopathy (ARVC). BACKGROUND Naxos disease is a recessively inherited ARVC caused by a mutation in the gene encoding plakoglobin (cell adhesion protein) in which the cardiac phenotype is associated with palmoplantar keratoderma and woolly hair. METHODS Twelve families with Naxos disease underwent cardiac and molecular genetic investigation. Serial cardiac assessment with annual resting 12-lead and 24-h ambulatory electrocardiogram (ECG) and two-dimensional echocardiography was performed during 1 to 16 years, median 7 +/- 6 years in all 78 surviving members. RESULTS Twenty-eight surviving members were homozygous and 40 were heterozygous for the mutation. All adults who were homozygous (n = 26) fulfilled the diagnostic criteria for ARVC, the youngest by the age of 13 years. In eight who were heterozygous, minor ECG or echocardiographic abnormalities were observed. Of the 26 subjects who were affected homozygotes, 92% showed ECG abnormalities, 92% ventricular arrhythmias, 100% right ventricular structural alterations and 27% left ventricular involvement. During follow-up (10 +/- 6 years), 16 (62%) developed structural progression, 12 (46%) arrhythmic events and 7 (27%) heart failure. The annual disease-related and sudden death mortality was 3% and 2.3%, respectively. CONCLUSIONS Autosomal recessive ARVC caused by a mutation in plakoglobin was 100% penetrant by adolescence. Affected subjects who were homozygous experienced progressive disease with adverse prognosis. A minority of subjects who were heterozygous showed minor ECG/echocardiographic changes, but clinically significant disease did not develop.

Combined chemical and optical methods for monitoring the early decay stages of surrogate human models.

As the body decays shortly after death, a variety of gases and volatile organic compounds (VOCs) constantly emanate. Ethical and practical reasons limit the use of human corpses in controlled, time-dependent, intervening experiments for monitoring the chemistry of body decay. Therefore the utilization of pig carcasses serves as a potential surrogate to human models. The aim of this work was to study buried body decay in conditions of entrapment in collapsed buildings. Six domestic pigs were used to study carcass decay. They were enclosed in plastic body bags after being partially buried with rubbles, resembling entrapment in collapsed buildings. Three experimental cycles were performed, employing two pig carcasses in each cycle; VOCs and inorganic gases were measured daily, along with daily visible and thermal images. VOCs were collected in standard sorbent tubes and subsequently analyzed using a Thermal Desorption/Gas Chromatograph/high sensitivity bench-top Time-of-Flight Mass Spectrometer (TD/GC/TOF-MS). A comprehensive, stage by stage, detailed information on the decay process is being presented based on the experimental macroscopic observations, justifying thus the use of pig carcasses as surrogate material. A variety of VOCs were identified including almost all chemical classes: sulfur, nitrogen, oxygen compounds (aldehydes, alcohols, ketones, acids and esters), hydrocarbons, fluorides and chlorides. Carcasses obtained from a pig farm resulted in more sulfur and nitrogen cadaveric volatiles. Carbon dioxide was by far the most abundant inorganic gas identified along with carbon monoxide, hydrogen sulfide and sulfur dioxide. Visual monitoring was based on video captured images allowing for macroscopic observations, while thermal camera monitoring which is mostly temperature dependent, resulted in highlighting the local micro-changes on the carcasses, as a result of the intense microbial activity. The combination of chemical and optical methods proved very useful and informative, uncovering hidden aspects of the early stages of decay and also guiding in the development of combined chemical and imaging methods for the detection of dead bodies.

A fully validated method for the simultaneous determination of 11 antidepressant drugs in whole blood by gas chromatography–mass spectrometry

Antidepressant drugs are widely used for the treatment of depression and other psychiatric disorders and as a result they are involved in numerous clinical and forensic cases. The aim of this study was the development, optimization and validation of a simple, specific and sensitive GC/MS method for the simultaneous determination of 11 antidepressant drugs and 4 of their metabolites (amitriptyline, citalopram, clomipramine, fluoxetine, fluvoxamine, maprotiline, desmethyl-maprotiline, mirtazapine, desmethyl-mirtazapine, nortriptyline, paroxetine, sertraline, desmethyl-sertraline, venlafaxine and desmethyl-venlafaxine) in whole blood. The combination of solid-phase extraction with derivatization using heptafluorobutyric anhydride efficiently reduced matrix effect and improved sensitivity of the method. In this assay, protriptyline was used as internal standard. Absolute recovery values for all analytes were ranged from 79.2 to 102.6%. LODs and LOQs were found to be between 0.30-1.50 μg/L and 1.00-5.00 μg/L, respectively. The calibration curves were linear (R(2)≥0.990) within the range of 5.00-1000 μg/L for all analytes. Accuracy expressed as the % E(r) was found to be between -12.3 and 12.2%. Precision expressed as the % RSD was found to be less than 11.7% for all antidepressants. The developed method proved to be suitable for routine work and it was used to successfully analyze more than 2500 clinical and forensic blood samples.

Identification and differential diagnosis of perimortem blunt force trauma in tubular long bones

The identification of perimortem injuries from human remains is crucial in the forensic evaluation of skeletal trauma. The purpose of this article is to review the criteria currently used by forensic experts for the identification and differential diagnosis of perimortem blunt force trauma in long bones. The mechanism of injury and the associated fracture pattern in long bones is discussed because it is fundamental in the forensic interpretation. The distinction between postmortem and perimortem fractures is based on the evidence of an osteogenic reaction. The first signs of healing can be detected macroscopically, radiographically, or histologically. Perimortem injuries may be distinguished from postmortem damage by examining certain attributes such as fracture angle and fracture margins. Additionally, the most commonly encountered taphonomic factors leading to postmorterm damage are described in order to alert the workers of the existence of such pitfalls that may perplex the forensic interpretation of skeletal trauma. Although the distinction of bone damage that occurred long after death from perimortem trauma is relatively easy, the differentiation of fractures inflicted shortly before death or soon after death may be difficult or even impossible.

Induction of metallothionein in the liver of carbon tetrachloride intoxicated rats: an immunohistochemical study.

Metallothioneins (MTs), are low molecular weight proteins, mainly implicated in metal ion detoxification. In the present study, we investigated the expression of hepatic MT in a rat model of injury and regeneration, induced by carbon tetrachloride (CCl(4)) administration. A single intraperitoneal injection of 1 ml CCl(4)/kg body weight was performed in male Wistar rats, killed at different time points post-administration. The enzymatic activities of aspartate and alanine aminotransferases in serum were determined, in addition to the liver histological findings, to estimate hepatotoxicity. The rate of tritiated thymidine incorporation into hepatic DNA, the enzymatic activity of thymidine kinase in liver tissue and the assessment of the mitotic index in hepatocytes, were used as indices of regeneration. MT was detected immunohistochemically in liver tissue sections. CCl(4) administration caused severe hepatic injury, followed by regeneration. MT expression became prominent as early as 12 h after the administration of CCl(4), in the nuclei of hepatocytes, while at 24 and 36 h intense cytoplasmic staining for MT appeared in the hepatocytes in the vicinity of necrotic areas. The peak of hepatocyte proliferative capacity, occurring at 48 h post-CCl(4) administration coincides with the maximum nuclear and cytoplasmic MT expression. At further time points MT expression presented a decreasing trend. Induction of MT expression was observed in the liver after a single administration of CCl(4), being more prominent at the time of maximum hepatocellular proliferation, participating actively in the replication of hepatocytes.

Development and validation of an EI–GC–MS method for the determination of benzodiazepine drugs and their metabolites in blood: Applications in clinical and forensic toxicology

Benzodiazepines are used widely in daily clinical practice, due to their multiple pharmacological actions. The frequent problems associated with the wide use of benzodiazepines, as well as the multiple incidents of poisonings, led to the necessity for the development of a precise, sensitive and rapid method for the simultaneous determination of the 23 most commonly used benzodiazepines (diazepam, nordiazepam, oxazepam, bromazepam, alprazolam, lorazepam, medazepam, flurazepam, fludiazepam, tetrazepam, chlordiazepoxide, clobazam, midazolam, flunitrazepam, 7-amino-flunitrazepam, triazolam, prazepam, nimetazepam, nitrazepam, temazepam, lormetazepam, clonazepam, camazepam) in blood. A gas chromatographic method combined with mass spectrometric detection was developed, optimized and validated for the determination of the above substances. This method includes liquid-liquid extraction with chloroform at pH 9 and two stages of derivatization using tetramethylammonium hydroxide and propyliodide (propylation), as well as a mixture of triethylamine:propionic anhydride (propionylation). The recoveries were higher than 74% for all the benzodiazepines. The calibration curves were linear within the dynamic range of each benzodiazepine with a correlation coefficient higher than 0.9981. The limits of detection and quantification for each analyte were statistically calculated from the relative calibration curves. Accuracy and precision were also calculated and were found to be less than 8.5% and 11.1%, respectively. The developed method was successfully applied for the investigation of both forensic and clinical toxicological cases of accidental and suicidal poisoning.

Forensic implications of carnivore scavenging on human remains recovered from outdoor locations in Greece

Mammalian carnivores rank among the most common scavengers of human remains. The present study discusses the forensic implications that carnivore scavenging had on human remains recovered from outdoor locations in Greece, and reviews the current literature on this subject. The forensic anthropological investigation indicated that carnivores were able to disarticulate and scatter body parts and personal effects over the recovery area, destroy skeletal elements and affect their survival, and alter or destroy indicators related with the cause and manner of death. In one case, scattering of bones over a considerable distance compromised the recovery efforts, causing later a problem in re-associating the skeletons. Other taphonomic factors than scavenging such as rolling of skeletal elements may be also responsible for the movement of bones. Carnivore scavenging was also responsible for the production of tooth marks on bone, and for bone removal especially noted on the articular ends of long bones. Matching different bone alterations with such activity is of vital importance since as it was seen carnivore scavenging can confound the interpretation of perimortem skeletal trauma.

Self-injurious behavior among Greek male prisoners: Prevalence and risk factors

BACKGROUND Self-harm among prisoners is a common phenomenon. This study aims to estimate the prevalence of self-injurious behavior (SIB) among Greek male prisoners, record their motives and determine independent risk factors. METHODS A self-administered, anonymous questionnaire was administered to 173 male prisoners in the Chalkida prison, Greece. The questionnaire included items on self-harm/SIB, demographic parameters, childhood history, family history, physical and mental disease, lifestyle and smoking habits, alcohol dependence (CAGE questionnaire), illicit substance use, aggression (Buss-Perry Aggression Questionnaire [BPAQ] and Lifetime History of Aggression [LTHA]), impulsivity (Barrat Impulsivity Scale-11) and suicidal ideation (Spectrum of Suicidal Behavior Scale). Univariate nonparametric statistics and multivariate ordinal logistic regression were performed. RESULTS Of all the participants, 49.4% (95% CI: 41.5-57.3%) disclosed self-harm (direct or indirect). The prevalence of SIB was equal to 34.8% (95% CI: 27.5-42.6%). Most frequently, SIB coexisted with indirect self-harm (80.7%). The most common underlying motives were to obtain emotional release (31.6%) and to release anger (21.1%). At the univariate analysis, SIB was positively associated with a host of closely related factors: low education, physical/sexual abuse in childhood, parental neglect, parental divorce, alcoholism in family, psychiatric condition in family, recidivism, age, sentence already served, impulsivity, aggression, alcohol dependence, self-reported diagnosed psychiatric condition and illicit substance use. Childhood variables were particularly associated with the presence of diagnosed psychiatric condition. At the multivariate analysis, however, only three parameters were proven independent risk factors: self-reported diagnosed psychiatric condition, illicit substance use and aggression (BPAQ scale). CONCLUSION The prevalence of SIB is particularly high. Psychiatric condition, illicit substance use and aggression seem to be the most meaningful risk factors; childhood events seem only to act indirectly.