Background: The transfemoral (TF) arterial approach is still the most commonly used approach for performing diagnostic coronary angiography in most centers in the world as well as in Bosnia and Herzegovina. Recently, the transradial (TR) arterial approach has gained more and more supporters among interventional cardiologists. Objective: The aim of the study was to compare the duration of the procedure, the amount of delivered ionizing radiation, the amount of applied contrast agent, the frequency of procedural complications and patient comfort during coronary angiography performed via TR and TF arterial approach. Methods: The total sample of 240 respondents was divided into two groups in such a way that the first group consisted of 121 respondents who underwent coronary angiography using TR arterial approach, and the second group consisted of 119 respondents who underwent coronary angiography using TF arterial approach. The Mann-Whitney U test was used to verify the research objective. Results: The obtained research results showed that the duration of coronary angiography and the amount of radiation was greater when using TR arterial approach compared to TF approach. There is no statistically significant difference in relation to the amount of applied contrast medium and the frequency of complications between the two approaches. Periprocedural and postprocedural comfort was better in patents who underwent TR approach. Conclusion: The findings of this study show that diagnostic coronary angiography performed via the TR arterial approach is as safe for the patient as diagnostic coronary angiography performed via the TF arterial approach. With both approaches, there is no significant difference in the amount of contrast agent used nor in the frequency of complications. Procedure duration and radiation exposure are shorter when TF arterial approach i used, while patient comfort is better when the TR arterial approach is used.

The aim of the research was to determine whether the age of the patient affects the duration of the procedure and the amount of ionizied radiation delivered when performing diagnostic coronary angiography. The research was conducted at the Clinic for Invasive Cardiology of the Public Health Institution "University Clinical Center" Tuzla in the period from December 2018. to January 2020. The research included a total sample of 240 respondents, average chronological age of 62.60 ± 9.22 years, ranging from 24 to 85 years. Out of a total of 240 respondents, in 121 respondents coronarny angiography was performed using transradial arterial approach and 119 by performing a transfemoral arterial approach. The total sample was divided into two subsamples of respondents. The first sub-sample consists of respondents up to 65 years of age, and the second sub-sample consists of respondents over 65 years of age. During each performance of coronary angiography, the duration of the procedure (in minutes and seconds) and the amount of radiation delivered during the procedure (in mGy) were measured. The research data were processed using the method of parametric and non- parametric statistics. The Mann-Whitney U test was used to verify the research objective. Based on the obtained research results, it can be concluded that in patients over 65 years of age, the duration of the coronary angiography procedure is longer, and is at the limit of statistical significance (p= 0.057). The amount of delivered radiation is higher in respondents over 65 years of age, but it is not statistically significant (p= 0.396). Keywords: Coronary angiography, coronary disease, procedure duration, age, amount of delivered radiation.

Background: Enormous number of medical journals published around the globe requires standardization of editing practice. Objective: The aim of this article was to enlist main principles of editing biomedical scientific journals adopted at annual meeting of Academy of Medical Sciences of Bosnia & Herzegovina (AMSB&H). Methods: The evidence for writing this Guideline was systematically searched for during September 2020 in the PUBMED and GOOGLE SCHOLAR databases. The inclusion criteria were: original studies, systematic reviews, invited expert opinions, guidelines and editorials. The exclusion criteria were narrative reviews and uninvited opinion articles. The retrieved evidence was analyzed by members of the AMSB&H, then discussed at 2020 annual meeting of the AMSB&H and adopted by nominal group technique. Results: In total 14 recommendations were made, based on A to C class of evidence. The editors should educate potential authors and instruct them how to structure their manuscript, how to write every segment of the manuscript, and take care about correct use of statistical tests. Plagiarism detection softwares should be used regularly, and statistical and technical editing should be rigorous and thorough. International standards of reporting specific types of studies should be followed, and principles of ethical and responsible behavior of editors, reviewers and authors should be published on the journal’s web site. The editors should insist on registration of clinical studies before submission, and check whether non-essential personal information is removed from the articles; when essential personal information has to be included, an article should not be published without signed informed consent by the patient to whom these information relate. Conclusions: Principles of editing biomedical scientific journals recommended in this guideline should serve as one of the means of improving medical journals’ quality.

Background: From 2013 the World Medical Association’s Declaration of Helsinki explicitly requires pre-registration of a study involving human subjects. The registration gives a chance for improvement of design and avoidance of bias. Objective: The aim of this article was to describe process of bearing decision to create regional registry of clinical studies for Balkan countries. Methods: After finding relevant studies about research registries and designing the concept and structure of future regional registry an article was published in IJBH journal. The article was than used as basis for discussion at 2020 meeting of Academy of Medical Sciences of Bosnia and Herzegovina (AMSBH), and final decision was made by the Academy to create the research registry. Results: Regional registry of clinical studies will be under the auspices of AMSBH and web-based, with the option of online registration of new studies. The data required to be entered in the moment of registration relate to key elements of research plan: topic, variables, sample, type of the study and the study population. After applying for registration of a clinical study, the authors will soon receive the review made by the AMSBH expert committee. The application could be accepted, rejected or returned for major or minor revision. After an application is accepted, it will be deposited in the searchable database and given the registration number. Conclusion: The AMSBH’s decision to create the regional registry of clinical studies will satisfy needs of researchers from Balkan countries in the first place, who share cultural and lingual similarities. It will also help with increasing standards of clinical research in the region.

Immersion tests with different stainless steels have been performed, while the pH was stepwise decreased and then increased again. During 8.5‐day exposure, the depassivation and repassivation pH values as a function of pitting resistance equivalent number were determined. There is always a gap between both pH values (depassivation and repassivation), indicating that for every steel, there are conditions where an existing passive layer can be maintained but cannot be rebuilt after depassivation. In such environments, the passive layer is thicker, consisting mainly of molybdenum and iron rich oxides, while chromium is dissolved. Usually, depending on conditions, the passive layer is more chromium‐rich, especially the inner layer. This is relevant, for example, for acidizing jobs in oil and gas industry, proving that repassivation after acidizing will happen promptly, when the pH is increased again.

On the occasion of the 11th Days of Academy of Medical Sciences of Bosnia and Herzegovina and 3rd Seminar about Writing, Editing and Publishing (SWEP) at Holiday hotel in Sarajevo was organized webinar about COVID-19 Pandemic experiences in Bosnia and Herzegovina. During the webinar members of the Academy from Bosnia and Herzegovina, Croatia, Serbia, North Macedonia, Poland, and USA participated with very interesting presentations (1-5). We also presented lecture about our institution and our professional experiences during pandemic time. Some of important facts which we presented are mentioned in this letter to editor. Medical Institute Bayer (MIB) is a continuation of the BH Heart Center Tuzla, which was founded in 2008. The goal of establishing the Center was to build a modern, functional hospital that will meet all prescribed norms and standards, and eliminate all limiting factors in the development of cardiac surgery, interventional cardiology and vascular surgery (Figure 1).

When planning oil wells with stainless steel components, two possible reasons for depassivation have to be considered—chemical depassivation caused by acidizing jobs and mechanical depassivation caused by various tools and hard particles. The study explores conditions causing chemical activation of investigated steels and circumstances under which repassivation occurs after activation. The main focus of the study is to determine, how quickly various steels can repassivate under different conditions and to find pH values where repassivation will occur after depassivation. The investigated steels were ferritic (martensitic or bainitic) in the cases of 13Cr, 13Cr6Ni2Mo, and 17Cr4Ni2Mo, austenitic in the case of 17Cr12Ni2Mo, and duplex (austenitic and ferritic) in the case of 22Cr5Ni3Mo. Potentiodynamic experiments were employed to obtain electrochemical properties of investigated steels, followed by immersion tests to find ultimate conditions, where the steels still retain their passivity. After obtaining this information, scratch tests were performed to study the repassivation kinetics. It was found that repassivation times are similar for nearly all investigated steels independent of their chemical composition and microstructure.