[Prevalence, clinical and morphological features of tooth root caries in the adult human]. / Rasprostranennost' i kliniko-morfologicheskie osobennosti kariesa kornia zuba u vzroslogo cheloveka.

The incidence of tooth root caries, the morphology of hard dental tissues and the clinical course of the pathology were studied in 4701 (2526 men and 2175 women) residents of St. Petersburg and the Leningrad Region aged 18 to 88 years, which were divided into age groups according to age periodization of Institute of Age Physiology RAS. The highest prevalence of tooth root caries was revealed in the older age groups making 9.88% in elderly age and 7.4% in old age. In young, 1st and 2nd mature age the tooth root caries was diagnosed relatively rare (in 0.26, 1.35 and 5.02% of cases, respectively). Morphological changes in the tooth root cement that predispose to the development of a carious process were determined. In the first adulthood the caries of the tooth root occurred against the background of gum recession in chronic generalized periodontitis especially diabetes patients. In people of the 2nd mature age, elderly and old age the caries of the tooth root was associated with poor oral hygiene, gingival recession due to periodontal disease, as well as in teeth supporting fixed or removable dentures.

Chimney Grafts in Aortic Stent Grafting: Hazardous or Useful Technique? Systematic Review of Current Data.

BACKGROUND: The chimney graft (CG) technique was introduced to rescue accidentally covered aortic branches during aortic endovascular repair. It extends the sealing zone. There is concern about "gutter" type I endoleak (EL-I) and about the durability of CGs. The aim of the present report was to analyze the rapidly increasing existing data. METHODS: A search was performed (PRISMA criteria) for all studies of visceral and thoracic/arch chimney grafts. Technical and clinical details and outcome were assessed. RESULTS: The present review includes 831 patients who underwent EVAR/TEVAR (endovascular aneurysm repair/thoracic endovascular aneurysm repair) with one or more chimney, periscope, or sandwich grafts. For aortic visceral vessels 517 patients received 911 visceral CGs and 314 patients received 364 arch CGs. Most procedures (81% visceral and 69% arch CGs) were elective. Thirty day mortality was 4% for both groups. The rate of early EL-I was 13% (visceral CGs) and 11% (arch CGs). Most EL-I were handled conservatively (observation: 70% for visceral CG and 45% for arch CG). Early CG patency was high (97-99%) and remained high during follow up (median 17 months). Late (after 30 days) EL-I was reported in nine visceral (2%) and 12 arch (4%) CG cases. Few other late complications were reported, but those losing a kidney at the initial repair seemed to have a high risk of requiring permanent hemodialysis. CONCLUSION: Increasing amounts of data support the benefit of visceral and arch chimney graft techniques. In particular, the low early mortality and complication rates and high long-term patency seem advantageous; however, the majority of cases have been treated electively, and there is a high risk of bias in all studies. Mid- to long-term data suggest few late complications, except in cases where one renal artery was sacrificed. The CG technique is valuable for complex urgent patients and needs further documentation for other patient groups.

The neutron dose equivalent rate measurements by R3DR/R2 spectrometers on the international space station.

The data from two Bulgarian-German instruments with the basic name "Radiation Risk Radiometer-Dosimeter" (R3D) are discussed. The R3DR instrument worked inside the ESA EXPOSE-R facility (2009-2010), while R3DR2 worked inside the ESA EXPOSE-R2 facility (2014-2016). Both were outside the Russian Zvezda module on the International Space Station (ISS). The data from both instruments were used for calculation of the neutron dose equivalent rate. Similar data, obtained by the Russian "BTNNEUTRON" instrument on the ISS are used to benchmark the R3DR/R2 neutron dose equivalent rate. The analisys reveals that the "BTNNEUTRON" and R3DR/R2 values are comparable both in the equatorial and in the South Atlantic Anomaly (SAA) regions. The R3DR/R2 values are smaller than the "BTNNEUTRON" values in the high latitude regions. The comparison with the Monte Carlo simulations of the secondary galactic cosmic rays (GCR) neutron ambient dose equivalent rates (El-Jaby and Richardson, 2015, 2016) also shows a good coincidence with the R3DR/R2 spectrometer data obtained in the equatorial and high latitude regions.

Moving forward with elective vascular work: a reflection on the impact of COVID-19 on a regional vascular hub.

INTRODUCTION: Following the initial COVID-19 surge in the UK, there was a national incentive for elective vascular surgery to be restricted to 'clean' sites to reduce perioperative cross-infection and subsequent mortality. We assessed the risk of dying from perioperatively acquired COVID-19 during the peak of the London outbreak. METHODS: Forty-three consecutive patients who had vascular (n=48) procedures in March and April 2020 at a regional hub serving five London hospitals were analysed. The patients were screened for COVID-19 in the 30-day postoperative period and the main outcome measure was mortality from COVID-19. A comparison was then made with patients who underwent minimally invasive procedures in our integrated interventional radiology department. Median follow-up was 41 days (interquartile range 8-58) overall. RESULTS: Three patients (7%) in the vascular group (median age 61 years, all diabetic, two male) died from COVID-19, all of whom tested positive postoperatively. Two others became positive but recovered. In comparison, two patients (2%) in the interventional radiology group died from COVID-19; however, one was positive prior to their procedure. CONCLUSION: Only urgent vascular cases should be performed during a COVID-19 surge. However, with growing waiting lists for elective surgery following the pandemic's second wave, further restrictions may not be a viable long-term solution. When prevalence of the disease is lower and if resources allow, resumption of care at 'hot' sites should be considered, if safety measures can be implemented. The advantages of minimally invasive surgery may also reduce risk.

Enteric neuronal development in canine small intestine - an immunohistochemical study.

The development of the enteric nervous system (ENS) is still a valid and intensely studied issue. However, literature in the field has no data on this topic in the dog. The present investigations were performed in three groups of fetuses from mongrel dogs - from the third, sixth- -seventh, and ninth week of pregnancy - and in 3-5-day-old puppies (3 specimens for each age group). The tissues (the medial parts of the duodenum, jejunum, and ileum with the cecum and a small portion of the adjacent ascending colon) were cut using a cryostat and the sections were processed for single- and double-labeling immunohistochemistry using antisera against acetylated tubulin (AcTub), vesicular acetylcholine transporter (VAChT), nitric oxide synthase (NOS), vasoactive intestinal polypeptide (VIP), galanin (GAL), neuropeptide Y (NPY), substance P (SP), and calcitonin gene-related peptide (CGRP). In the 3-week-old fetuses, some oval cells invading the gut wall were found. From the seventh week of pregnancy onwards, two different enteric ganglia were present: submucosal and myenteric. The estimated number of nerve elements in the 9-week-old fetuses was much higher than that observed in the 6-7-week-old individuals. There was no significant difference in the estimated number of nerve structures between the 9-week-old fetuses and the 3-5-day-old puppies. The colonization pattern and the development of the ENS in the canine small intestine are very similar to those observed in other mam- mals. However, a few exceptions have been confirmed, regarding the time of appearance of the VIP-, GAL-, and CGRP-immunoreactive neurons, and their distribution in different portions of the canine bowel during development.

Mid-term outcome of endovascular revascularization for chronic mesenteric ischaemia.

BACKGROUND: : This study aimed to assess mid-term outcome after endovascular revascularization of chronic occlusive mesenteric ischaemia (CMI) and to identify possible predictors of mortality. METHODS: : Consecutive patients undergoing primary elective stenting for CMI between 1995 and 2007 were registered prospectively in a database. Patients with acute ischaemia were excluded. Retrospective case-note review and data analysis were performed. RESULTS: : Forty-three patients (10 men) were treated for stable (n = 30) or exacerbated (n = 13) CMI. Their median (interquartile range (i.q.r.)) age was 70 (60-79) years. Revascularization was successful in 47 of 49 vessels. The superior mesenteric artery (SMA), either alone (n = 34) or in combination with the coeliac trunk (n = 6), was the predominant target vessel. No patient died within 30 days. Median follow-up was 43 (i.q.r. 25-63) months and the estimated (s.e.) 3-year overall survival rate was 76(7) per cent. Two patients died from distal SMA occlusive disease and intestinal infarction after 6 and 18 months respectively. Previous stroke (P = 0.016), male sex (P = 0.057) and age (P = 0.066) were associated with mid-term mortality on univariable, but not multivariable analysis. Reintervention was needed in 14 patients, achieving a 3-year cumulative rate of freedom from recurrent symptoms of 88(5) per cent. CONCLUSION: : Endovascular treatment provided high early and mid-term survival rates in this series of patients with CMI, with low complication rates.

Intra-aneurysm sac pressure in patients with unchanged AAA diameter after EVAR.

OBJECTIVE: To study intra-aneurysm sac pressure and subsequent abdominal aortic aneurysm (AAA) diameter changes in patients without endoleaks that remain unchanged in AAA diameter more than 1 year after endovascular aneurysm repair (EVAR). METHODS: A total of 23 patients underwent direct intra-aneurysm sac pressure (DISP) measurements 16 months (IQR: 14-35 months) after EVAR. Tip-pressure sensors were used through translumbar AAA puncture. Mean pressure index (MPI) was calculated as the percentage of mean intra-aneurysm pressure relative to the simultaneous mean intra-aortic pressure. Aneurysm expansion or shrinkage was assumed whenever the diameter change was > or =5mm. Values are presented as median and interquartile range. RESULTS: In 18 patients, no fluid was obtained upon AAA puncture (group A). In five patients, fluid was obtained (group B). In group A, follow-up continued for 29 months (IQR: 15-35 months) after DISP; five AAAs shrank, 10 remained unchanged and three expanded (MPIs of 26% (IQR: 18-42%), 28% (IQR: 20-48%) and 63% (IQR: 47-83%) and intra-sac pulse pressures of 3 mmHg (IQR: 0-5 mmHg), 4 mmHg (IQR: 2-8mm Hg) and 12 mmHg (IQR: 6-20 mmHg), respectively, for the three subgroups). MPI and intra-sac pulse pressures were higher in AAAs that subsequently expanded (P=0.073 and 0.017, respectively). MPI and pulse pressure correlated with total diameter change (r=0.49, P=0.039 and r =0.39, P=0.109, respectively). Pulse pressure had a greater influence than MPI on diameter change (R(2)=0.346, P=0.041, beta standardised coefficient of 0.121 for MPI and 0.502 for pulse pressure). Similar results with stronger, and significant correlation to pulse pressure were obtained when relative diameter changes were used (r=0.55, P=0.017). In group B, MPI and AAA pulse pressure were 32% (IQR: 18-37%) and 1 mmHg (IQR: 0-6 mmHg), respectively. After 36 months (IQR: 21-38 months), one AAA shrank, three continued unchanged while one expanded. CONCLUSIONS: AAAs without endoleak and unchanged diameter more than 1 year after EVAR will often continue unchanged. Expansion can eventually occur in the absence of intra-sac fluid accumulation and is associated with higher and more pulsatile intra-sac pressure. However, in patients with intra-sac fluid, expansion can occur with low intra-sac pressures.

Incidence and management of complications after branched and fenestrated endografting.

Endovascular treatment of complex aortic aneurysms with fenestrated and branched stentgrafts is in rapid development. Early and midterm results from centers of excellence are very promising but the technique is still in its infancy. With the introduction of EVAR for complex aneurysms a new set of failure modes have also been introduced. These relate both to the specific deployment techniques of the devices and to their intrinsic design characteristics. Procedural planning is of utmost importance for success. Failure to accomplish this may result in disastrous and uncorrectable perioperative failure. The endograft must be correctly tailored to the patient with regards to branch and fenestration positioning and design. Migration of stent-graft components, target vessel occlusions due to branch compression or dislocation and fenestration malpositioning must be recognized during follow up and treated accordingly. The clinical consequences of complex aneurysm repair include spinal cord ischemia and peripheral embolisation and strategies to handle this must be present.

Aortocaval fistula, a potentially favourable complication of abdominal aortic aneurysm rupture in endovascular repair.

Endovascular aneurysm repair is an established treatment for ruptured abdominal aortic aneurysm. Primary aortocaval fistula is an exceedingly rare finding in ruptured abdominal aortic aneurysm, with a reported incidence of less than 1%. The presence of an aortocaval fistula used to be an unexpected finding in open surgical repair which often resulted in massive haemorrhage and caval injury. We present a case of ruptured abdominal aortic aneurysm with an aortocaval fistula that was successfully treated with percutaneous endovascular aneurysm repair under local anaesthesia. Despite a persistent type 2 endoleak the aneurysm sack shrank from 8.4cm to 4.8cm in 12 months. The presence of an aortocaval fistula may have depressurised the aneurysm, resulting in less bleeding retroperitoneally and may have promoted rapid shrinkage of the sac despite the presence of a persistent type 2 endoleak.

Solar modulation of the GCR flux and dose rate, observed in space between 1991 and 2019.

The paper presents the solar modulation of the long-term galactic cosmic rays (GCR) flux and dose rates variations, observed during 14 space experiments by 10 Bulgarian build Liulin-type spectrometers (LTS) (Dachev et al., 2015a). They worked in near Earth space and in the interplanetary radiation environment between January 1991 and January 2019. Data were collected by LTS in the low Earth orbit (LEO) in the L range between 4 and 6.2 or outside the magnetosphere. The major advantage of the data sets are that they are obtained by the electronically identical LTS. The Liulin measurements of about monthly averaged flux and dose rate data are compared with the monthly values of the modulation parameter, reconstructed from the ground based cosmic ray data (Usoskin et al., 2017). A good correlation between the two data sets is observed. The most important achievement of the paper is that for the first time a proof of the solar modulation of the long-term variations of the monthly averaged dose rates is obtained. These long-term experimentally obtained dose rate data could be used for modeling of the GCR space radiation risks to humans in the near Earth radiation environment. Parallel to the long-term dose rate varitions, the monthly averaged flux variations are also presented.

Mutagenesis in Escherichia coli by visible light.

Mutation to resistance to bacteriophage T5 in continuous cultures of Escherichia coli was induced by visible light (wavelength longer than 408 nanometers) and by black light (300 to 400 nanometers). Mutation rates more than 18 times greater than the spontaneous rate (no light) were obtained with moderate, nonlethal intensities of visible light. Mutation rates for both visible and black light were proportional to irradiance.

Is there a benefit of frequent CT follow-up after EVAR?

OBJECTIVE: Imaging follow-up (FU) after endovascular aneurysm repair (EVAR) is usually performed by periodic contrast-enhanced computed tomography (CT) scans. This study aims to evaluate the effectiveness of CT-FU after EVAR. METHODS: In this study, 279 of 304 consecutive patients (261 male, aged 74 years (interquartile range (IQR): 70-79 years) with a median abdominal aortic aneurysm (AAA) diameter of 58 mm (IQR: 53-67 mm)) underwent at least one of the yearly CT scans and plain abdominal films after EVAR. All patients received Zenith stent-grafts for non-ruptured AAAs at a single institution. Patients were considered asymptomatic when a re-intervention was done solely due to an imaging FU finding. The data were prospectively entered in a computer database and retrospectively analysed. RESULTS: As a follow-up, 1167 CT scans were performed at a median of 54 months (IQR: 34-74 months) after EVAR. Twenty-seven patients exhibited postoperative AAA expansion (a 5-year expansion-free rate of 88+/-2%), and 57 patients underwent 78 postoperative re-interventions with a 5-year secondary success rate of 91+/-2%. Of the 279 patients, 26 (9.3%) undergoing imaging FU benefitted from the yearly CT scans, since they had re-interventions based on asymptomatic imaging findings: AAA diameter expansion with or without endoleaks (n=18), kink in the stent-graft limbs (n=4), endoleak type III due to stent-graft limb separation without simultaneous AAA expansion (n=2), isolated common iliac artery expansion (n=1) and superior mesenteric artery malperfusion due to partial coverage by the stent-graft fabric (n=1). CONCLUSIONS: Less than 10% of the patients benefit from the yearly CT-FU after EVAR. Only one re-intervention due to partial coverage of a branch by the stent-graft would have been delayed if routine FU had been based on simple diameter measurements and plain abdominal radiograph. This suggests that less-frequent CT is sufficient in the majority of patients, which may simplify the FU protocol, reduce radiation exposure and the total costs of EVAR. Contrast-enhanced CT scans continue, nevertheless, to be critical when re-interventions are planned.

Management of inadvertent arterial catheterisation associated with central venous access procedures.

OBJECTIVE: This study aims to describe the clinical management of inadvertent arterial catheterisation after attempted central venous catheterisation. METHODS: Patients referred for surgical or endovascular management for inadvertent arterial catheterisation during a 5-year period were identified from an endovascular database, providing prospective information on techniques and outcome. The corresponding patient records and radiographic reports were analysed retrospectively. RESULTS: Eleven inadvertent arterial (four common carotid, six subclavian and one femoral) catheterisations had been carried out in 10 patients. Risk factors were obesity (n=2), short neck (n=1) and emergency procedure (n=4). All central venous access procedures but one had been made using external landmark techniques. The techniques used were stent-graft placement (n=6), percutaneous suture device (n=2), external compression after angiography (n=1), balloon occlusion and open repair (n=1) and open repair after failure of percutaneous suture device (n=1). There were no procedure-related complications within a median follow-up period of 16 months. CONCLUSIONS: Inadvertent arterial catheterisation during central venous cannulation is associated with obesity, emergency puncture and lack of ultrasonic guidance and should be suspected on retrograde/pulsatile catheter flow or local haematoma. If arterial catheterisation is recognised, the catheter should be left in place and the patient be referred for percutaneous/endovascular or surgical management.

Early and intermediate outcome of emergency endovascular aneurysm repair of ruptured infrarenal aortic aneurysm: a single-centre experience of 90 consecutive patients.

OBJECTIVE: To evaluate the early and intermediate outcome of a consecutive series of emergency endovascular aneurysm repairs (eEVAR) of computed tomography (CT)-verified infrarenal ruptured abdominal aortic aneurysm (rAAA) at a single tertiary referral centre. METHODS: Prospectively collected data of patients operated between April 2000 and October 2007 were retrospectively reviewed and all their pre-, intra- and postoperative imaging were re-evaluated. Patient and procedural data were analysed using a Cox multiregression model. RESULTS: Ninety patients (86% men, aged 76 (+/-7) years), were identified and included in the analysis. Symptom duration was <3h in 22% of patients, 3-24h in 39% and >24h in 39%. Mean aneurysmal diameter was 73 (+/-14)mm. All patients were treated with the COOK Zenith stent-graft (56% bi-iliac and 44% uni-iliac). Sixty-one percent were haemodynamically unstable on presentation, and 26% required an intra-operative aortic occlusion balloon to maintain haemodynamic stability. The 30-day and 1-year mortality rates were 27% and 37%, respectively. One-year aneurysm-related mortality was 33%. Twenty-eight percent of patients required re-interventions during the follow-up. The use of an aortic occlusion balloon and the presence of cerebrovascular disease or obstructive lung disorder correlated significantly with 30-day mortality in the multivariate analysis. CONCLUSION: EVAR is a valid treatment option for rAAA when used as a first-line method for all patients.

The applicability of chimney grafts in the aortic arch.

AIM: Proximal fixation is often limiting for thoracic endovascular aortic repair (TEVAR) and the stent graft may need to cover the origin of the arch branch vessels. Chimney grafts have been proposed to preserve flow into over stented branches during urgent TEVAR. The aim of this report is to share our initial experience of this technique. METHOD: Eleven patients underwent urgent TEVAR combined with a chimney graft between January 2004 and April 2009. The indications included acute complicated type B dissection (N. = 2), ruptured aneurysms of the aortic arch (1) and descending aorta (2), traumatic aortic transaction (1), aortoesophageal fistula (1) and accidental over stenting of the left carotid artery during TEVAR (4). Chimney grafts were implanted into the innominate (N. = 3), left carotid (7) and left subclavian (1) arteries. Mean length of follow up was 20 months. RESULTS: All chimney grafts were successfully implanted. Two patients developed a primary proximal type I endoleak: one leak was successfully coil embolized, the other awaits treatment. One paraplegia was reversed by spinal drainage but two months later, this patient presented with a contained rupture and underwent successful conversion to open repair. No other postoperative aneurysm expansion has occurred and the chimney grafts remain patent. The only aneurysm related death occurred in a patient with an unrecognized chronic occlusion of his right carotid artery who received a left carotid chimney graft and suffered from a lethal stroke. CONCLUSION: Chimney grafts in the supra-aortic branches seem feasible and may facilitate urgent TEVAR in patients with an inadequate proximal neck.

Effectiveness of fascial closure technique following percutaneous endovascular aneurysm repair.

INTRODUCTION: Percutaneous access and closure is commonly performed for patients undergoing endovascular aneurysm repair (EVAR). It has proven to be a safe and successful method of closure associated with fewer complications when compared with the traditional open technique. Fascial closure is an alternative technique that can be used for closure reducing the risks associated with the open technique. The aim of this study was to assess the safety and durability of fascial closure for failed percutaneous closure device following EVAR. MATERIALS AND METHODS: Over a 12-month period, 49 patients who had undergone EVAR were identified via our EVAR register. Retrospective analysis of the clinical records was undertaken. We identified all the patients who had fascial closure of the groins following a failed percutaneous closure device. Patients had a computed tomography angiogram one month postoperatively, with duplex imaging and clinic follow-up three months later. RESULTS: Fascial closure was performed in 14 groins. It failed in three groins and these patients had traditional open repair. Fascial closure was successful in 11 groins (7 patients). Of these seven patients, one was female (6%). The mean age was 80 years (range 68-92 years). Two patients died and one was lost to follow-up. One pseudoaneurysms were seen on computed tomography angiogram, which was managed conservatively and had resolved on follow-up imaging. CONCLUSIONS: Fascial closure is a very good alternative to open repair after failure of the closure device.

EVAR of aortoiliac aneurysms with branched stent-grafts.

INTRODUCTION: Branched iliac stent-grafts (bSG) have recently been developed in order to preserve internal iliac artery (IIA) flow in patients with aneurysmal or short common iliac arteries. The aim of this study is to evaluate a single-center experience with bSG for the IIA. METHODS: Twenty-two male patients (70 (IQR 65-79) years old) underwent EVAR with 23 bSG (1 bilateral repair) between September 2002 and August 2007. Median AAA diameter was 52 (37-60) mm while common iliac diameter on the side of the bSG was 34 (27-41) mm. Two in-house modified Zenith SG and subsequently 21 commercially available bSG (18 Zenith Iliac Side and 3 Helical Branches) were used. Follow-up (FU) included CT at one month and yearly thereafter. Data was prospectively entered in a database. RESULTS: Primary technical success was 91% (21 bSG). Median FU duration was 20 (8-31) months. One patient (5 %) died after discharge from acute myocardial infarction on day 13. Another patient died 30 months after EVAR of an unrelated cause. The overall bSG patency was 74% due to 6 branch occlusions (2 intraoperative and 4 late). All patients with patent bSG were asymptomatic. Three occlusions were asymptomatic findings on CT, while the other three developed claudication (two patients with contralateral IIA occlusion and one with simultaneous occlusion of the external iliac). One patient (5%) developed an asymptomatic type III endoleak at 1 month and was successfully treated with a bridging SG. Overall, four patients (18%) required reinterventions (1 bilateral stenting of the external iliac arteries, 1 external and 1 internal SG extensions and 1 femoro-femoral cross-over bypass). Nine out of 16 patients (56%) with CT-FU>/=1 year had shrinking aneurysms. There were no postoperative aneurysm expansions. CONCLUSIONS: EVAR of aortoiliac aneurysms with IIA bSG is a good alternative to occlusion of the IIA in patients with challenging distal anatomy.

EVAR and complex anatomy: an update on fenestrated and branched stent grafts.

Endovascular aneurysm repair (EVAR) offers a minimally invasive treatment to patients with improved short-term and similar mid-term results compared to conventional, open repair (OR). EVAR is preferred by patients due to the reduction of surgical trauma. Approximately 20% of patients have aneurysm neck morphology which is inadequate for a standard stent graft and requires the endograft to cross vital aortic side branches to achieve a seal. This chapter describes the evolution of three types of devices, namely the fenestrated and branched stent grafts as well as the chimney grafts. These stent grafts incorporate vital aortic side branches in the repair, thereby increasing the applicability of EVAR which may improve the overall results.