Outcome of Heart Transplant Candidates Based on a High Volume Heart Transplant Center Experience in Iran.

Background: The waiting list for heart transplants is a valuable data registry that would offer very useful information on the characteristics of patients who have various outcomes while waiting in the list. Objective: The purpose of this study was to look at the prognosis of those waiting for heart transplants as well as the factors that increase mortality. Methods: Advanced heart failure patients' demographic, clinical, hemodynamic, and echocardiographic results, as well as their prognosis, were retrieved from the national registry for heart transplantation between 2011 and 2018. The study population was defined and compared in four groups: 1) Death while awaiting HTX, 2) Death after HTX, 3) Alive without a transplant, 4) Transplanted and alive. Results: The data of 207 patients [75% male, mean (SD) age of 34(10) years] were analyzed. The most common etiology of heart failure was idiopathic dilated cardiomyopathy. A total of 86 patients (41%) were successfully transplanted, with a median (IQR) time between listing and transplantation of 84 (30¬219) days, 54 patients (26.1%) were dead and 32% were still alive. The multivariate analysis showed right atrial pressure, pulmonary capillary wedge pressure, cardiac index, and systolic blood pressure at the time of listing as independent predictors of death. Conclusion: The study on HTX waiting list is very useful for both allocation strategies and administrative planning for patients with advanced heart failure by development of accurate models and scoring systems using predictors of death in the waiting list.

A double layer FSS filter for sub-THz applications.

This work presents the simulated and measured performance of single- and double-layer frequency selective surface filters for operation at sub-THz frequencies (250 GHz center frequency). They were composed of concentric square loops with a split as a unit cell resonator on top of a low dielectric permittivity, low thickness material (RT5880). Both a single layer filter and a cascaded two layer filter with varied distances were investigated. The simulated bandwidth for the cascaded filter was 27 GHz and 16 GHz and 9 GHz bandwidth measured with a THz-TDS and microwave system.

Impact of the Iranian Registry of Infective Endocarditis (IRIE) and multidisciplinary team approach on patient management.

BACKGROUNDS: The last 30 years have witnessed major improvements in understanding of all aspects of infective endocarditis (IE). The Iranian Registry of Infective Endocarditis (IRIE) was formed to address epidemiological aspects of IE vis-à-vis its main pathogens and underlying heart diseases over a 12-year period. Indeed, a multidisciplinary team (MDT) for IE was developed alongside. METHODS: In a longitudinal observational study, data of adult patients with definite or possible IE based on modified Duke criteria were collected from 2007 to 2016 in our tertiary centre, Iran. From 2016 until 2019, we run a prospective observational study using formation of an IE MDT to provide better patient management and compared data before and after this. RESULTS: Totally, 645 patients with mean age of 48 ± 17 years were enrolled. Data of 445 and 200 patients were compared before and after IRIE and MDT formation, respectively. We found significantly reduced type and number of applied antibiotics (p = 0.04) and higher rate of positive blood culture (p = 0.001). Hospital length of stay increased significantly after formation of the IRIE and IE MDT (p = 0.02). The rate of heart failure, new abscess formation and cerebral emboli were significantly decreased after IRIE and IE MDT (p < 0.001) and consequently in-hospital mortality reduced significantly (p = 0.05). CONCLUSION: Developing national registries and MDTs has potential to enhance patient management and reduce IE burden. Our results demonstrated that establishment of the Iranian IRIE and IE MDT conferred better diagnoses, standardised treatments and significantly reduced cardiac and extra cardiac morbidity.

Attitude and Knowledge of Medical Students of Tabriz University of Medical Sciences Regarding Organ Donation.

BACKGROUND: The shortage of organ donation is the key rate-limiting factor for organ transplantation in Iran. Many strategies have been proposed to increase donation; one strategy aims to improve awareness of organ donation and transplantation among medical students. Medical students may play an important role in the acceptance of organ donation in the population. This requires both a positive attitude and an appropriate knowledge about the concept of organ donation and transplantation. The objective of this study was to determine the knowledge and attitude of the medical students of the largest medical university in northwestern Iran. METHODS: Four hundred medical students in the 5th and 6th years of their education were enrolled in this study. They completed a self-administered 3-section questionnaire. Section 1 gathered demographic characteristics, section 2 covered attitude, and section 3 assessed knowledge regarding organ donation. RESULTS: The concept of brain death and criteria involved in organ transplant was understood by 57% of the students. Most of the students thought that there is a need to increase awareness regarding brain death and organ donation transplantation (ODT). Eighty-five percent of the students said that they would donate their organs, but 15% did not, most likely because of religion and body disfigurement. Seventy-eight percent of students would donate their organs to their family, relatives, or friends. Sixty-four percent thought that the family can decide regarding ODT. Seventy percent were willing to donate the organs of their family members after brain death. Religion and source of information regarding ODT has a significant effect on knowledge and attitude of students. CONCLUSIONS: Students had a high level of attitude, but a low level of basic understanding about organ donation that lacked detailed knowledge. They accept its importance and desire further teaching to supplement their current knowledge to be able to understand the issues related to organ donation. The results of this study supported a greater emphasis on revising the curricula in medical schools to improve the knowledge of future health care workers. This strategy may be part of the solution to the chronic shortage of donor organs for transplantation.

TATA binding protein-associated CK2 transduces DNA damage signals to the RNA polymerase III transcriptional machinery.

Here we report that RNA polymerase (pol) III transcription is repressed in response to DNA damage by downregulation of TFIIIB, the core component of the pol III transcriptional machinery. Protein kinase CK2 transduces this stress signal to TFIIIB. CK2 associates with and normally activates the TATA binding protein (TBP) subunit of TFIIIB. The beta regulatory subunit of CK2 binds to TBP and is required for high TBP-associated CK2 activity and pol III transcription in unstressed cells. Transcriptional repression induced by DNA damage requires CK2 and coincides with downregulation of TBP-associated CK2 and dissociation of catalytic subunits from TBP-CK2 complexes. Therefore, CK2 is the terminal effector in a signaling pathway that represses pol III transcription when genome integrity is compromised.

A review of progress towards elucidating the role of protein kinase CK2 in polymerase III transcription: regulation of the TATA binding protein.

We have investigated the molecular basis of the requirement for protein kinase CK2 in nuclear transcription in Saccharomyces cerevisiae. In vivo and in vitro analysis has demonstrated that CK2 is required for efficient transcription of the tRNA and 55 rRNA genes by RNA polymerase III. This suggests that a component of the pol III transcription machinery is regulated by CK2. We tested this possibility by a biochemical complementation approach in which components of the pol III transcription machinery from wild type cells were tested for their ability to rescue transcription in extract from a conditionally CK2-deficient mutant. We found that pol III transcription initiation factor IIIB (TFIIIB) fully restores transcription in CK2-deficient extract. Further in vitro studies revealed that TFIIIB must be phosphorylated to be active, that a single subunit of wild type TFIIIB, the TATA binding protein (TBP), is efficiently phosphorylated by CK2, and that recombinant TBP and a limiting amount of CK2 rescues transcription in CK2-deficient extract. We conclude that TBP is the physiological target of CK2 among the components of the pol III transcription machinery. The implications of this result are discussed in the context of previous data concerning the regulation of TFIIIB.

Rapamycin induces the G0 program of transcriptional repression in yeast by interfering with the TOR signaling pathway.

The macrolide antibiotic rapamycin inhibits cellular proliferation by interfering with the highly conserved TOR (for target of rapamycin) signaling pathway. Growth arrest of budding yeast cells treated with rapamycin is followed by the program of molecular events that characterizes entry into G0 (stationary phase), including the induction of polymerase (Pol) II genes typically expressed only in G0. Normally, progression into G0 is characterized by transcriptional repression of the Pol I and III genes. Here, we show that rapamycin treatment also causes the transcriptional repression of Pol I and III genes. The down-regulation of Pol III transcription is TOR dependent. While it coincides with translational repression by rapamycin, transcriptional repression is due in part to a translation-independent effect that is evident in extracts from a conditional tor2 mutant. Biochemical experiments reveal that RNA Pol III and probably transcription initiation factor TFIIIB are targets of repression by rapamycin. In view of previous evidence that TFIIIB and Pol III are inhibited when protein phosphatase 2A (PP2A) function is impaired, and that PP2A is a component of the TOR pathway, our results suggest that TOR signaling regulates Pol I and Pol III transcription in response to nutrient growth signals.

Casein kinase II regulation of yeast TFIIIB is mediated by the TATA-binding protein.

The highly conserved protein kinase casein kinase II (CKII) is required for efficient Pol III transcription of the tRNA and 5S rRNA genes in Saccharomyces cerevisiae. Using purified factors from wild-type cells to complement transcription extracts from a conditional lethal mutant of CKII we show that TFIIIB is the CKII-responsive component of the Pol III transcription machinery. Dephosphorylation of TFIIIB eliminated its ability to complement CKII-depleted extract, and a single TFIIIB subunit, the TATA-binding protein (TBP), is a preferred substrate of CKII in vitro. Recombinant TBP purified from Escherichia coli is phosphorylated efficiently by CKII and, in the presence of a limiting amount of CKII, is able to substantially rescue transcription in CKII-deficient extract. Our results establish that TBP is a key component of the pathway linking CKII activity and Pol III transcription and suggest that TBP is the target of a CKII-mediated regulatory mechanism that can modulate Pol III transcription.