Mendelian diseases and conditions in Croatian island populations: historic records and new insights

Among Croatian islands, there are several which are known for unusual autochthonous diseases and specific medical conditions that result from the reproductive isolation and specific population genetic structure. These populations are characterized by high degree of genetic isolation, consanguinity, and inbreeding. The reported diseases include Mal de Meleda on Mljet island, hereditary dwarfism on Krk island, familial learning disability on Susak island, familial ovarian cancer on Lastovo island, and several other rare diseases and conditions inherited in Mendelian fashion. We present a historical perspective on how these conditions were first described, interpreted, and assessed. We reviewed the information obtained through genetic research in the past several years, when the genetic etiology of some of these conditions was explained. The disease gene causing Mal de Meleda was first localized at 8q chromosome, and mutations in the ARS (component B) gene encoding SLURP-1 (secreted mammalian Ly-6/uPAR-related protein 1) protein were identified subsequently. The genetic etiology of dwarfism on the island of Krk is explained by a mutation in the PROP1 gene, responsible for the short stature. The search for mutations underlying other monogenic diseases in Croatian islands is under way.     

Effects of analgesic or antidepressant drugs on pain- or stress-evoked hippocampal and spinal neurokinin-1 receptor and brain-derived neurotrophic factor gene expression in the rat

Clinical studies show that people suffering from chronic pain are often also burdened by depression. Antidepressants are used to treat some types of chronic pain; however, little is known about their mechanisms of action. This study addressed the effects of a nonsteroidal anti-inflammatory drug and a tricyclic antidepressant drug on pain- and stress-evoked gene expression in the rat spinal cord dorsal horn and hippocampus. Rats were pretreated with either indomethacin or imipramine and then challenged with either intraplantar complete Freund's adjuvant or a bout of immobilization stress. Results showed that indomethacin significantly reduced nociception-related peripheral edema, hyperalgesia, and reversed the pain-evoked up-regulation of neurokinin (NK)-1 receptor and brain-derived neurotrophic factor (BDNF) gene expression in the spinal cord to levels not statistically different from controls. However, indomethacin did not protect against significant pain-induced down-regulation of these genes in the hippocampus by approximately 50%, suggesting that although analgesic drug treatment reduces nociceptive sensory activation in the spinal cord, it is insufficient to prevent the impact of pain on the hippocampus. Conversely, although imipramine did not provide significant behavioral analgesia, it significantly blocked both pain- and stress-evoked alterations in hippocampal and spinal NK-1 and BDNF gene expression. Thus, these results show that application of either analgesic or antidepressant drugs alone does not fully protect against both the behavioral and molecular effects of persistent pain on both "sensory" and "affective" processing within the central nervous system.     

Pre-term delivery and periodontal disease: a case-control study from Croatia

AIM: The aim of this report was to assess the strength and influence of periodontitis as a possible risk factor for pre-term birth (PTB) in a cohort of 81 primiparous Croatian mothers aged 18-39 years. METHODS: PTB cases (n = 17; mean age 25 +/- 2.9 years; age range 20-33 years) were defined as spontaneous delivery after less than 37 completed weeks of gestation that were followed by spontaneous labour or spontaneous rupture of membranes. Controls (full-time births) were normal births at or after 37 weeks of gestation (n = 64; mean age 25 +/- 2.9 years; age range 19-39 years). Information on known risk factors and obstetric factors included the current pregnancy history, maternal age at delivery, pre-natal care, nutritional status, tobacco use, alcohol use, genitourinary infections, vaginosis, gestational age, and birth weight. Full-mouth periodontal examination was performed on all mothers within 2 days of delivery. RESULTS: PTB cases had significantly worse periodontal status than controls (p = 0.008). Multivariate logistic regression model, after controlling for other risk factors, demonstrated that periodontal disease is a significant independent risk factor for PTB, with an adjusted odds ratio of 8.13 for the PTB group (95% confidence interval 2.73-45.9). CONCLUSION: Periodontal disease represents a strong, independent, and clinically significant risk factor for PTB in the studied cohort. There are strong indicators that periodontal therapy should form a part of preventive prenatal care in Croatia.     

Uncertainty in predictions of disease spread and public health responses to bioterrorism and emerging diseases

Concerns over bioterrorism and emerging diseases have led to the widespread use of epidemic models for evaluating public health strategies. Partly because epidemic models often capture the dynamics of prior epidemics remarkably well, little attention has been paid to how uncertainty in parameter estimates might affect model predictions. To understand such effects, we used Bayesian statistics to rigorously estimate the uncertainty in the parameters of an epidemic model, focusing on smallpox bioterrorism. We then used a vaccination model to translate the uncertainty in the model parameters into uncertainty in which of two vaccination strategies would provide a better response to bioterrorism, mass vaccination, or vaccination of social contacts, so-called "trace vaccination." Our results show that the uncertainty in the model parameters is remarkably high and that this uncertainty has important implications for vaccination strategies. For example, under one plausible scenario, the most likely outcome is that mass vaccination would save approximately 100,000 more lives than trace vaccination. Because of the high uncertainty in the parameters, however, there is also a substantial probability that mass vaccination would save 200,000 or more lives than trace vaccination. In addition to providing the best response to the most likely outcome, mass vaccination thus has the advantage of preventing outcomes that are only slightly less likely but that are substantially more horrific. Rigorous estimates of uncertainty thus can reveal hidden advantages of public health strategies, suggesting that formal uncertainty estimation should play a key role in planning for epidemics.     

Diagnostic Yield of Electroencephalography in a General Inpatient Population

ObjectiveTo determine the frequency and clinical predictors of seizures and markers of epileptiform activity in a non–critically ill general inpatient population.Patients and MethodsWe performed a retrospective cohort study of patients 18 years and older who underwent inpatient electroencephalography (EEG) between January 1, 2005, and December 31, 2010, for an indication of spells or altered mental status. The EEGs and reports were reviewed for ictal activity, interictal epileptiform abnormalities, and nonepileptiform abnormalities. Demographic and clinical data were gathered from the electronic medical record to determine seizure predictors.ResultsOf 2235 patients screened, 1048 met the inclusion criteria, of which 825 (78.7%) had an abnormal EEG finding. Seizures occurred in 78 of 1048 patients (7.4%), and interictal epileptiform discharges were noted in 194 of 1048 patients (18.5%). An intracranial mass and spells as the indication for the EEG were independently associated with the group of patients experiencing seizures in a multivariate logistic regression model (adjusted for age, sex, EEG indication, intracranial mass, stroke, and history of epilepsy). Ninety-seven percent of patients (69 of 71) experienced their first seizure within 24 hours of monitoring, and the presence of seizures was associated with a lower likelihood of being discharged (odds ratio, 0.45; 95% CI, 0.27-0.76).ConclusionSeizures occurred at a high frequency in hospitalized patients with spells and altered mental status. The EEG may be an underused investigative tool in the hospital with the potential to identify treatable causes of these common disorders.     

The cardiorenal syndrome and erythropoietin

The pathophysiological condition, in which combined cardiac and renal dysfunction amplifies a progression in the failure of the individual organ, has been denoted as severe cardiorenal syndrome (SCRS). An interactive network of cardiorenal connectors, i.e., the renin-angiotensin system (RAS), nitric oxide (NO) and reactive oxygen species (ROS) balance, the sympathetic nervous system (SNS), and inflammation, has been proposed as the cornerstones of the pathophysiology of SCRS. Because erythropoietin (Epo) production declinesin chronic renal failure (CRF) and Epo sensitivity might decrease by the cardiorenalconnectors in patients with the SCRS, it is not surprising thatanaemia is a commonly occurring state coinciding with CRF and chronic heart failure (CHF). Epo treatment in patients with SCRS acts via haematopoietic effects, but also may intervenes in the vicious circle of cardiorenal connectors with subsequent deteriorating effects on cardiac, renal, and vascular function. It appears that regular Epo treatment in anaemic patients with diminished renal function improves cardiac performance, delays the progression of kidney disease, and may be of clinical benefit even to patients suffering from CHF with relatively mild anaemia. Despite growing evidence about Epo having positive effects on both renal and cardiac function, little is known about the underlying mechanisms of action.     

A single-nucleotide polymorphism (SNP) multiplex system: the association of five SNPs with human eye and hair color in the Slovenian population and comparison using a Bayesian network and logistic regression model

Aim

To analyze two phenotype characteristics – eye and hair color – using single-nucleotide polymorphisms (SNPs) and evaluate their prediction accuracy in Slovenian population.

Methods

Twelve SNPs (OCA2 – rs1667394, rs7170989, rs1800407, rs7495174; HERC2 – rs1129038, rs12913832; MC1R – rs1805005, rs1805008; TYR – rs1393350; SLC45A2 – rs16891982, rs26722; SLC24A5 – rs1426654) were used for the development of a single multiplex assay. The single multiplex assay was based on SNaPshot chemistry and capillary electrophoresis. In order to evaluate the accuracy of the prediction of eye and hair color, we used the logistic regression model and the Bayesian network model, and compared the parameters of both.

Results

The new single multiplex assay displayed high levels of genotyping sensitivity with complete profiles generated from as little as 62 pg of DNA. Based on a prior evaluation of all SNPs in a single multiplex, we focused on the five most statistically significant in our population in order to investigate the predictive value. The two prediction models performed reliably without prior ancestry information, and revealed very good accuracy for both eye and hair color. Both models determined the highest predictive value for rs12913832 (P < 0.0001), while the other four SNPs (rs1393350, rs1800407, rs1805008, and rs7495174) showed additional association for color prediction.

Conclusion

We developed a sensitive and reliable single multiplex genotyping assay. More samples from different populations should be analyzed before this assay could be used as one of the supplemental tools in tracing unknown individuals in more complicated crime investigations.Height, face structure, pigmentation of the eye, hair, and skin, the presence of freckles, and male baldness make up human externally visible characteristics (EVC). To be able to predict eye and hair color based solely on biological material left behind at a crime scene or obtained from dismembered missing persons, or even of disaster victims, is one of the major expectations from the routine forensic work in the near future (1). However, genetic understanding of human appearance is still in its infancy, mainly due to the fact that all EVCs are polygenic traits. This means that yields from a large number of different genes and the expression of these genes are further influenced by mutual interactions and environmental interactions (2). Above all, molecular mechanisms and functional protein assays must also be considered in order to really understand how allelic variation in pigmentation genes could result in such a diversity of phenotypes in different human populations (3). The human eye (iris) and hair color are one of the most highly polymorphic phenotypes in people of European origin. The non-brown iris colors and red hair are generally features of European origin resulting from positive selection in early European history. There are several hypotheses for positive selection that mainly occurred in the Baltic region and Northern Europe. These are most likely: UV exposure causing skin cancer, vitamin D deficiency, and even sexual selection (4,5). Most EVCs are complex traits with many genes and single nucleotide polymorphism (SNP) variations, so the right combination of SNPs is crucial for the correct prediction of eye and hair color. Several genome-wide association studies (GWAS) for pigmentation have revealed that SNPs within the HERC2, OCA2, MC1R, SLC24A5, SLC45A2, TYR, and ASIP (4,6-16) genes were most strongly associated with eye and hair color in European populations. The latest data have shown that the main iris color variation is associated with a highly evolutionarily preserved region in the HERC2 gene or within the short sequence between the HERC2 and OCA2 genes. It is assumed that these regions represent a regulatory region controlling the constitutive expression of OCA2 (4,11,12). As for iris color, it has also been explained that red hair color is mainly associated with polymorphisms in the MC1R gene (13,17). On the other hand, the variations of genes such as SLC24A5, SLC45A, HERC2, and ASIP seem to be responsible for influencing the shades of hair color from blond to black (18,19).In order to correctly predict human eye and hair color from genetic data for the Slovenian population, we compared two alternative prediction models that are nowadays used most often in this field of forensics – the Bayesian network model and the logistic regression model. These models were developed and compared on the basis of the informative SNPs selected from our single multiplex assay.     

How health care professionals confront and solve ethical dilemmas – a tale of two countries: Slovenia and Croatia

AimTo assess the differences in the way how Slovenian and Croatian health care professionals (HCPs) confront ethical dilemmas and perceive the role of hospital ethics committees (HECs).MethodsThis cross-sectional, survey-based study involved HCPs from three Slovenian and five Croatian university medical centers (UMC). The final sample sizes were 308 (244 or 79.2% women) for Slovenia and 485 (398 or 82.1% women) for Croatia.ResultsCompared with Croatian physicians, Slovenian physicians reported a higher share of ethical dilemmas regarding waiting periods for diagnostics or treatment, suboptimal working conditions due to interpersonal relationships in the ward, and end-of-life treatment withdrawal, and a lower share regarding access to palliative care and patient information protection. Compared with Croatian nurses, Slovenian nurses reported a lower share of ethical dilemmas regarding the distribution of limited resources, recognizing the patient’s best interests, and access to palliative care. Compared with Croatian other HCPs, Slovenian other HCPs reported a lower burden of ethical dilemmas regarding waiting periods for diagnostics or treatment, distribution of limited resources, and access to palliative care. When encountering an ethical dilemma, all HCPs in both countries would first consult their colleagues. Slovenian and Croatian HCPs recognized the importance of the HECs to a similar extent, but viewed their role differently.ConclusionCroatian and Slovenian HCPs are confronted with different ethical dilemmas and perceive the role of HECs differently.

An ethical dilemma arises when we are confronted with a situation with two morally justifiable solutions, none of which is entirely satisfactory (1). In the course of their daily work, health care professionals (HCPs) encounter a broad range of ethical dilemmas (2-4), which often result in a moral distress for HCPs (5,6). A critical requirement for a successful response to an ethical dilemma is a strong foundation in medical professionalism cultivated during medical training and consolidated during professional work experience and career development (7-9).Slovenia and Croatia, previously the westernmost republics of the former Yugoslavia and now European Union members, share the same historical, geopolitical, economic, and religious background. A recent survey in the largest Slovenian tertiary hospital, the University Medical Center Ljubljana, found that the most important contexts that give rise to ethical dilemmas among HCPs were waiting periods for diagnostics and treatment, suboptimal working conditions due to poor interpersonal relationships, and preserving patients'' dignity, while the least important contexts were biomedical research, organ transplantation, and vaccine hesitancy (10). A study at the University Medical Center Rijeka found similar main ethical dilemmas in Croatian nurses and physicians, which included limiting life-sustaining therapy, euthanasia, and physician-assisted suicide (11).Except these two studies, little to nothing is known about the ethical dilemmas of HCPs in Slovenia and Croatia. In response to this limited evidence, we conducted a prospective survey with a primary objective to assess the differences in the share of ethical dilemmas among different categories of HCPs (physicians, nurses, and other HCPs) in Slovenian and Croatian tertiary hospitals (university medical centers, UMCs). The UMCs were purposively selected because in this kind of hospitals, one encounters complicated cases usually referred from other health care institutions for complex diagnostic and therapeutic procedures, which can often raise ethical issues. The secondary objectives of our survey were to study differences in the opinion on the existence of standard procedures when HCPs are facing an ethical dilemma; to determine whom HCPs consult when facing an ethical dilemma; and to identify the opinion on the importance of hospital ethics committees (HECs) and their role in Slovenia and Croatia.