Open transaortic implantation of 'Medlab-KT' prosthesis. / Otkrytaia transaortal'naia implantatsiia proteza 'Medlab-KT'.

AIM: The study was aimed at comparing the immediate clinical and haemodynamic results of open implantation of the balloon-expandable aortic prosthesis 'MedLab-KT' with the respective parameters of standard replacement of the aortic valve by a mechanical prosthesis in high-risk surgical patients. PATIENTS AND METHODS: We analysed a total of 209 cases of prosthetic repair of the aortic valve. The Study Group comprised 28 patients subjected to open implantation of the 'MedLab-KT' prosthesis in conditions of extracorporeal circulation and myocardial ischaemia and belonging to a high-surgical risk cohort. The Comparison Group included 181 patients who endured standard open prosthetic repair of the aortic valve with a mechanical prosthesis. Using the ppropensity score matching method, we selected 28 patients from the Comparison Group, followed by assessing the incidence of adverse clinical events and haemodynamic parameters of the aortic valve prosthesis at the in-hospital stage. RESULTS: There were no lethal outcomes in the study group, with one in the group of standard aortic valve repair - 3.6%. The mean operative time in the Study and Comparison Group patients amounted to 121.5±51.2 and 274.2±55.3 min (p=0.04), the duration of extracorporeal circulation to 56.1±19.5 and 119.9±23.4 min (p=0.04), that of myocardial ischaemia to 38.4±17.1 and 96.7±20.8 (p=0.03), respectively. The mean gradient on the aortic valve in the 'MedLab-KT' group was less (7.5±3.2 mm Hg) than in those of the second group (9±3.5 mm Hg), with no statistically significant differences in the parameters revealed (p=0.096). All patients of the study group were discharged from hospital in a satisfactory condition, with the haemodynamic result of the operation regarded as satisfactory. CONCLUSION: Comparing the main clinical characteristics and haemodynamic parameters in the groups of 'MedLab-KT' and aortic valve prosthetic repair at the hospital stage revealed no statistically significant differences. Open implantation of the 'MedLab-KT' prosthesis proved safe and effective.

[First serial transcatheter implantation of pulmonary valve using MedLab-KT prosthesis]. / Pervaia seriinaia transkateternaia implantatsiia klapana legochnoi arterii pri pomoshchi proteza (MedLab-KT).

BACKGROUND: Surgical treatment of 'blue' congenital heart defects frequently implies various interventions on the outlet portion of the right ventricle or pulmonary artery trunk. Most often used are various conduits, reconstructing the outlet portion of the right ventricle and pulmonary artery. Most patients having previously endured the mentioned interventions, would in the remote terms require repeat operative procedures for stenosis or insufficiency on the pulmonary valve or the implanted conduit. Taking into account complexity and the risk of open interventions, the current trends are towards more frequent use of transcatheter implantation of the pulmonary valve. AIM: The purpose of this work is to present the first serial experience with hybrid transventricular implantation of an original Russian-made valve into the position of the pulmonary artery. PATIENTS AND METHODS: We retrospectively studied a series of 5 clinical cases who from July 2019 to May 2020 at the Federal Centre of Cardiovascular Surgery (Penza) had underwent hybrid transventricular implantation of the first Russian-made valve-containing stent (MedLab-KT) into the position of the pulmonary valve, with the stent's closing component consisting of leaflets made of polytetrafluoroethylene. RESULTS: 3 patients underwent implantation of valve # 25 and 2 subjects received valve # 23, with all cases yielding good immediate results. The haemodynamic parameters of the implanted prosthesis were optimal. In all cases, the significant gradient was absent and regurgitation did not exceed grade I. There was no in-hospital mortality. The method of hybrid prosthetic repair of the pulmonary valve via the transapical right-ventricular access from the left lateral mini-thoracotomy was aimed at reducing potential risks of artificial circulation, also contributing to a significant decrease in the traumatic nature of surgical treatment of patients requiring a repeat intervention for pulmonary valve pathology.

[Transcatheter aortic valve replacement after Ozaki procedure]. / Transkateternoe protezirovanie aortal'nogo klapana posle protsedury Ozaki.

The Ozaki operation is currently considered to be a sufficiently known surgical procedure performed in aortic valve defects. Despite satisfactory results in the mid-term period after neocuspidalization, there have been reported cases of pronounced aortic insufficiency due to rupture of neocusps or their endocarditis. Transcatheter aortic valve replacement is a rapidly developing trend at the junction of modern cardiac surgery and interventional cardiology, expansively covering groups of patients at high, moderate and recently also low surgical risk. Repeat open cardiosurgical interventions remain a zone of especially increased risk of complications. This clinical case report describes technical aspects and immediate outcomes of successful transcatheter implantation of aortic valve prosthesis in a patient with aortic insufficiency revealed 2 years after the Ozaki procedure.

[Transcatheter valve-in-valve implantation of the 'MedLab-KT' prosthesis]. / Transkateternaia implantatsiia proteza 'MedLab-KT' po metodike 'klapan-v-klapan'.

Valve-in-valve repeat prosthetic reconstruction is a less invasive alternative to 'open' redo operation for degenerative dysfunction of an aortic bioprosthesis. At the beginning of the history of using this method it was resorted to only in cases of high surgical risk, involving virtually inoperable patients. Currently, the world experience numbers in thousands of such interventions, known to be also performed in patients not belonging to a high-risk group. Recent studies have demonstrated a decrease in the perioperative mortality and improved quality of life in the remote period after valve-in-valve transcatheter implantation of an aortic bioprosthesis. High gradients, occlusion of coronary arteries, and thrombosis of the prosthesis's leaflets remain the major problems encountered while using this method. Nevertheless, valve-in-valve prosthetic reconstruction proved to be a reliably safe and efficient procedure of correcting dysfunction of a previously implanted biological prosthesis.

[Transcatheter replacement of pulmonary artery valve with a graft containing polytetrafluoroethylene leaflets]. / Transkateternaia zamena klapana legochnoi arterii protezom so stvorkami iz politetraftorétilena.

Annually, many operations for repeat prosthetic reconstruction of the pulmonary artery valve are performed due to dysfunction after primary correction of both congenital and acquired heart defects. Open operations with artificial circulation are associated with a high surgical risk. Transcatheter implantation is a new and progressive technique of heart valve replacement. Until recently, implantation of only a biological graft in the position of a pulmonary artery valve was possible, but a limited service life and high risk of the development of infective endocarditis stimulate search for new solutions of this problem. In the he present work we describe cases concerning placement of the first Russian-made valve-containing stent in the position of the pulmonary artery, with the stent's closing mechanism made of polytetrafluoroethylene thus giving ground to count on more favourable results.

H-shaped partial splenorenal shunting with the use of a reinforced graft made of porous polytetrafluoroethylene. / N-obraznoe partsial'noe splenorenal'noe shuntirovanie s ispol'zovaniem armirovannogo proteza iz poristogo politetraftorétilena.

AIM: The study was aimed at improving the immediate and remote results of splenorenal bypass grafting. PATIENTS AND METHODS: A total of 57 patients presenting with hepatic cirrhosis, portal hypertension, and recurrent haemorrhage from oesophageal varices underwent an H-shaped partial splenorenal shunt procedure using an externally reinforced 1.5-2.0-cm-long synthetic graft with a diameter equalling half of that of the splenic vein in an end-to-side fashion. Assessment of efficacy of shunting was based on intraoperative measurement of venous pressure in the portal system before and after shunting, the findings of Doppler ultrasonography of the linear velocity of blood flow in the portal, splenic, and left renal veins in the early postoperative period, as well as computed tomography, esophagogastroscopy, and assessment of the degree of hepatic encephalopathy in the remote postoperative period. RESULTS: The findings of intraoperative measurement of venous pressure in the portal vein system before and after shunting demonstrated a statistically significant decrease in (normalization of) portal pressure in all patients after bypass grafting (p≤0.05). There were no severe postoperative complications, in-hospital mortality, nor events of decompensation of hepatic insufficiency. According to the findings of Doppler ultrasonography of the linear velocity of blood flow and control computed tomography after surgery, the splenic vein, left renal vein and the conduit between them remained patent at all terms of postoperative follow up. The findings of control esophagogastroscopy revealed a statistically significant decrease in the degree of oesophageal varices at 3, 6, and 9 months after shunting (p≤0.05). There was no statistically significant difference in the change of the degree of hepatic encephalopathy at 3, 6, and 9 months after shunting (p=0.853, p=0.712, and p=0.581, respectively). At various terms after surgery, nine patients underwent deceased donor liver transplantation, with the splenorenal shunt ligated intraoperatively. CONCLUSION: This method of splenorenal shunting makes it possible to decrease the risk of bleeding from oesophageal varices and venous thromboses in vascular anastomoses, as well as complications resulting from using autovenous conduits, to decrease the risk of decomposition of hepatic insufficiency and the frequency of the development of encephalopathy in the postoperative period. Besides, this method makes it possible to easily dismantle the previously created artificial portocaval shunt in the process of liver transplantation.

Immediate results of bypass grafting of the territory of the right coronary artery using the 'Penza Coronary Technology'. / Neposredstvennye rezul'taty shuntirovaniia basseina pravoi koronarnoi arterii s ispol'zovaniem metodiki 'Penza Coronary Technology'.

Coronary artery bypass grafting (CABG) is known to be an effective method of treatment for multivessel obstructive coronary disease with low rates of reintervention and excellent long-term survival and freedom from angina. Graft patency lies at the heart of its procedural success and durability, which in its turn largely depends on the appropriate choice of the conduit, as well as the target coronary artery (CA). It should be mentioned that patency of one and the same conduit used for bypass grafting of the territory of either the left or right coronary artery (LCA and RCA, respectively) may differ, which is probably determined by differences in physiology, size, territory of runoff, and local flow characteristics between different coronary targets. Previous reports have supported the use of bilateral internal thoracic arteries to revascularize the left coronary circulation. If this becomes standardized practice, the optimal conduit for the right coronary system remains to be established. Proposed in the present article is a variant of bypass grafting of the RCA territory using a composite I-graft formed from the proximal portion of the right internal thoracic artery (ITA) in situ and the great saphenous vein (GSV) harvested by the 'no-touch' technique. This technique is part of a CABG schematic algorithm worked out in our Clinic and called the 'Penza Coronary Technology'.

Indications for ascending aorta-bifemoral bypass grafting in patients with IHD and occlusion of the infrarenal aorta. / Pokazaniia dlia astsendo-bifemoral'nogo shuntirovaniia u patsientov s IBS i okkliuziei infrarenal'noi aorty.

The problem concerning surgical decision-making in patients with significant atherosclerotic lesions of arteries of more than one basin will, probably, be important for cardiovascular surgeons for more than one decade. Even the centres possessing experience in several thousand cases of successful treatment of multifocal atherosclerosis have from time to time been facing non-trivial clinical situations requiring a non-standard decision the recommendations for which could hardly be found in the guidelines available, if at all. This article describes the technique and immediate results of an operation making it possible to simultaneously carry out revascularization of the myocardium and lower limbs in patients diagnosed as having a critical coronary lesion and Leriche syndrome with no intervention on the abdominal portion of the aorta. Also given is a detailed description of the technique of performing ascending aorta-bilateral femoral arteries bypass combined with coronary artery bypass grafting. Also presented herein are the data from publications having described this operation previously. Our article for the first time demonstrates the findings of intraoperative flowmetry, proving the leading role of the internal thoracic arteries for collateral blood supply of lower limbs in occlusion of the terminal portion of the aorta. This test lays a pathophysiological foundation for the necessity of a simultaneous intervention on the vessels of two basins.

[Autotransplantation of the internal carotid artery in patients with high localization of an atherosclerotic plaque]. / Autotransplantatsiia vnutrennei sonnoi arterii u patsientov s vysokim rasprostraneniem ateroskleroticheskoi bliashki.

Acute and chronic cerebral circulatory impairment is a very commonly encountered type of neurological diseases, annually affecting more than six million people worldwide. The absolute majority of all cases are associated with atherosclerosis of cerebral arteries. Surgical intervention in a stenotic lesion of the internal carotid artery (ICA) is a method of preventive treatment with confirmed efficacy. Eversion carotid endarterectomy (ECEA) is currently the most commonly used 'open' operation for this cohort of patients. It is connected with relative technical simplicity of the operative procedure, no foreign material in the wound, low risk of haemodynamic disorders in the zone of reconstruction owing to no considerable alteration in the ICA diameter, as well as favourable remote results. A disadvantage of ECEA is lack of visual control above the distal portion of the ICA and, as a consequence, limited application of the technique in cases of a highly located atherosclerotic plaque (by more than 2 cm above the bifurcation). Specialists of the Federal Centre of Cardiovascular Surgery in the city of Penza worked out a modification of the operative technique making it possible to widen the indications for using ECEA. Its essence consists in total resection of the stenosed portion of the ICA, performing eversion endarterectomy outside the wound, followed by reimplantation thereof with the help of two 'end-to-end' anastomoses, as during prosthetic repair. This technique was called autotransplantation of the ICA. Advantages of this technique are considered to include precision of removing the plaque and intimal ruptured fragments, which is easier and more convenient to achieve outside the wound; reliable fixation of the intima and non-stenosing residuals of the plaque by a distal anastomosis, as well as a possibility of using this technique in cases of high location of the plaque. The purpose of this study was to compare the immediate results_outcomes of ECEA and autotransplantation of the ICA in two groups comprising 108 and 72 patients, respectively. The measures assessed included the mean time of ICA cross-clamping during surgery, frequency of the development of perioperative strokes, haemorrhage, lesions of craniocerebral nerves, wound complications.

[Prevention of wound infection in cardiac surgery: how much is topical use of antibiotics justified?].

The authors studied efficacy of preventing wound infection of a sternotomic wound with and without conventional use of topical antibiotics, also determining predictors of the development of infectious complications after cardiosurgical interventions. Our retrospective study included a total of 1,593 patients subdivided into two groups. In Group One patients (n=951) sternal infection was prevented according to the P. Vogt technique; Group two patients (n=642) were also subjected to the same methodology, but with the exception of topical use of antibiotics. By the frequency of re-sternotomies performed, cases of superficial and deep wound infection, as well as by the average duration of operation, hospital and ICU stay there were no statistically significant differences between the groups (p<0.05). The average cost of antibacterial agents as calculated per one patient in Group One turned out substantially higher than in Group Two (amounting to 8.1±3.9 and 3.3±1.4 thousand roubles, respectively, p<0.001). Analysing possible predictors of the risk for the development of wound infection showed that the body mass index, duration of the operation, and performing re-sternotomy exerted a statistically significant influence on probability of infections complications. It was determined that using the methodology of preventing sternal infection with topical application of antibiotics led to predominance of Gram-negative flora in the wound discharge (p=0.02). Exclusion of topical use of antibiotics does not lead to an increase in the incidence rate of wound complications (p=0.78) and normalizes the ratio of Gram-negative and Gram-positive strains.

[Assessment of remote survival in patients with peripheral atherosclerosis after endured interventions on coronary arteries].

The article deals with a retrospective analysis of the risk for the development of unfavourable outcomes in vascular patients after interventions on coronary arteries versus those without them. The authors assessed remote survival in patients with atherosclerotic lesions of the coronary and vascular beds as compared with isolated coronary artery bypass grafting. All patients were at the Federal Centre for Cardiovascular Surgery from October 2008 to December 2009 and later on underwent planned examination at a polyclinic. The patients were subdivided into the following groups: Group 1 comprised a total of 131 vascular patients undergoing single-stage or stepwise operations on coronary arteries (CA) (CABG + peripheral vascular disease). They were also subjected to interventions on the abdominal aorta, carotid arteries and lower-limb arteries. Group 2 (PVD) comprised a total of 153 vascular patients without myocardial revascularization with documented indications for coronary artery bypass grafting according to the findings of coronography and noninvasive methods of examination. Group 3 (CABG) consisted of 258 patients without symptoms of peripheral atherosclerosis who underwent CABG and were examined at a polyclinic over the same period of time as the study groups. The findings of examination confirmed the world-literature discussed proposition suggesting that preventive CABG considerably improves the long-term prognosis for vascular patients. This is of special importance taking into consideration that a preventive intervention on CA brings no additional risk of operative treatment.

[Comparative study of the results of using stagewise open interventions and single-step hybrid operations in patients with coronary artery disease accompanied by lesions of carotid arteries].

The authors describe herein the technique of a hybrid single-stage intervention performed in patients presenting with coronary artery disease (CAD) combined with carotid artery atherosclerosis, as well as comparing the outcomes of using similar operations with the results of stagewise open interventions within a 30-day postoperative period. High risk for the development of severe and not uncommonly fatal complications both in the carotid basin and coronary bed determines difficulty of therapeutic decision-making regarding this patient cohort. This problem has been the subject of study and discussion in both Russian and foreign literature for more than two decades. However, none of the currently existing techniques has yet been accepted as an optimal one. The hybrid approach is a relatively novel technique, with the number of publications describing its application being only sporadic. The present article demonstrates significantly better immediate results of using the hybrid technique, thus suggesting that it may well be considered as an alternative to the classical approaches, requiring however further studies.

Imaging the electron-phonon interaction at the atomic scale.

Thin Pb films epitaxially grown on 7×7 reconstructed Si(111) represent an ideal model system for studying the electron-phonon interaction at the metal-insulator interface. For this system, using a combination of scanning tunneling microscopy and inelastic electron tunneling spectroscopy, we performed direct real-space imaging of the electron-phonon coupling parameter. We found that λ increases when the electron scattering at the Pb/Si(111) interface is diffuse and decreases when the electron scattering is specular. We show that the effect is driven by transverse redistribution of the electron density inside a quantum well.

[Simultaneous operations on the carotid and coronary arteries - the risk is due to?].

The article deals with the findings of a retrospective study regarding the incidence of risk factors for unfavourable outcomes during interventions on coronary arteries in patients presenting with atherosclerotic lesions of the carotid basin as compared to aortocoronary bypass grafting alone, followed by analysing individual risk factors. Also evaluated herein is the incidence rate of complications after coronary bypass grafting in patients presenting with various concomitant pathology, followed by determining the relative risk influencing hospital mortality both by groups as a whole and with due regard for stratification along the most significant risk factors. The study comprised a total of 74 patients with combined atherosclerotic lesions of carotid and coronary arteries, who were simultaneously subjected to revascularization of the myocardium and carotid basin. The control group was composed of 1,128 patients undergoing coronary bypass grafting alone. All patients were treated at the Federal Centre for Cardiovascular Surgery under the Russian Federation Ministry of Public Health and Social Development (Penza) from October 2008 to December 2011. The obtained findings confirmed the proposition that a simultaneous intervention of the CA does not increase the postoperative complications rate. The method of stratification demonstrated that the risk for the development of lethal outcomes in such patients turned out considerably higher. Patients with CA stenosis run higher risks of operational vascular complications, which is confirmed by a comparable level of mortality, cerebral strokes and myocardial infarction with the stratified group of patients having similar incidence of risk factors. Preventive interventions on the CA are aimed at decreasing operative complications and bring no additional risk to the lethality rate.

Structure and antibacterial properties of Ag-doped micropattern surfaces produced by photolithography method.

Photolithography methods offer ample opportunities for creating biological surface patterns over large areas. Herein, samples with patterned surface having the same Ag total coverage area and content, but different surface topography made of periodically spaced Ag/Si pillars with a diameter of 10 and 50 µm and a height of 3, 1, and 0.2 µm were produced by photolithography technique and studied to uncover the dependences of bactericide ion release on surface topography and antibacterial effect on Ag+ ion concentration. Reactive ion etching of Si wafers in areas unprotected by Ag capping layer was accompanied by a number of competing processes: (i) formation of Ag particles on the tops of pillars due to temperature-activated diffusion and coalescence, (ii) sputtering of Ag from the pillar to surface and redeposition into the etching cavities, resulting in the formation of small Ag nanoparticles located in areas between pillars, (iii) precipitation of AgSix phase as a result of chemical interaction of sputtered Si ions with Ag ions and atoms in surrounding plasma. Samples with the largest pillar heights which had also Ag particles formed between pillars demonstrated the fastest Ag+ ion release and, correspondingly, a noticeable antibacterial effect toward antibiotic-resistant hospital Escherichia coli K-261 strains already after 3 h. All samples showed 100% antibacterial effect after 24 h. Thus our results open up new possibilities for the production of scalable micropattern surfaces with controlled bactericide ion release and pronounced antibacterial characteristics for future applications in the orthopedic field.

The Sukhumi primate monkey model for viral lymphomogenesis: high incidence of lymphomas with presence of STLV-I and EBV-like virus.

T-cell leukemia virus-like proviral sequences (STLV-I) as well as EBV-like sequences were detected in PBLs and tissues of non-human primates (Papio hamadryas baboons, Green monkeys and Macaca arctoides; Sukhumi Primate Center/Georgia) by PCR. Surprisingly, two different types of STLV-I within Papio hamadryas baboons were found. One of its represents the baboon prototype STLV-I-Su described earlier, present in lymphomatous baboons from the "high-lymphoma stock", which shows about 83% homology to HTLV-I and 85% to STLV-I in the env and tax genes. The inter-individual variability within this subtype is very low (about 1% in the tax gene). The second subtype was mainly found in asymptomatic animals from the control colony and showed in the env gene 95% homology to HTLV-I, but only 82% to the prototype baboon sequence. The presence of two subtypes within the Sukhumi baboon population might be interesting in respect to the inoculation experiments with human leukemic blood and to possible interspecies transmissions. The nature of the Herpes Papio-virus was elucidated as EBV-like and the homology to the human EBV was > 90% in the polymerase gene. The homologies between different monkey species were between 92 and 96% and also here two subtypes within the baboons were detected. This is the first direct demonstration by sequencing that the Herpes Papio virus is closely related to EBV. For further studies of this animal model, rabbits were inoculated with cells originated from lymphomatous baboons and macaques. The rabbits developed generalized lymphomas lethal within 1-2 months. EBV-like and STLV-I-like sequences could be detected by PCR and sequencing showed 99-100% identity to the inoculum, indicating in fact the transmission from monkey to rabbit. These animal models seem to be very suitable for the elucidation of the pathogenesis of human HTLV-I associated T-cell leukemia/lymphoma and might be further on used for therapeutical and preventative studies.

Dynamic modulation of electronic properties of graphene by localized carbon doping using focused electron beam induced deposition.

We report on the first demonstration of controllable carbon doping of graphene to engineer local electronic properties of a graphene conduction channel using focused electron beam induced deposition (FEBID). Electrical measurements indicate that an "n-p-n" junction on graphene conduction channel is formed by partial carbon deposition near the source and drain metal contacts by low energy (<50 eV) secondary electrons due to inelastic collisions of long range backscattered primary electrons generated from a low dose of high energy (25 keV) electron beam (1 × 10(18) e(-) per cm(2)). Detailed AFM imaging provides direct evidence of the new mechanism responsible for dynamic evolution of the locally varying graphene doping. The FEBID carbon atoms, which are physisorbed and weakly bound to graphene, diffuse towards the middle of graphene conduction channel due to their surface chemical potential gradient, resulting in negative shift of Dirac voltage. Increasing a primary electron dose to 1 × 10(19) e(-) per cm(2) results in a significant increase of carbon deposition, such that it covers the entire graphene conduction channel at high surface density, leading to n-doping of graphene channel. Collectively, these findings establish a unique capability of FEBID technique to dynamically modulate the doping state of graphene, thus enabling a new route to resist-free, "direct-write" functional patterning of graphene-based electronic devices with potential for on-demand re-configurability.

Molecular characterization of human T-lymphotropic virus, type 1 (HTLV-1) found in Kuwait: close similarity with HTLV-1 isolates originating from Mashhad, Iran.

Human T-lymphotropic virus, type 1 (HTLV-1) infection was detected in two unrelated Kuwaiti patients with tropical spastic paraparesis (HAM/TSP) and in the asymptomatic mother of one of them. The family roots of these patients were traced to the Najaf region of Iraq. The DNA sequence of three PCR-amplified fragments (env, 512 bp; pol, 140 bp; LTR, 704 bp) was determined for each of Kuwaiti HTLV-1 isolates (KUW-1,2,3). All three Kuwaiti HTLV-1 were identical in env and pol fragments and virtually identical in LTR. Two rare substitutions were found in the env and pol fragments. They were shared only with two isolates from Reunion Island (substitution in env), and two isolates from India and the Caribbean (substitution in pol). The sequences of env and pol fragments of the Middle Eastern HTLV-1 isolates were not available. However, the comparison of Kuwaiti isolates with representative Middle Eastern HTLV-1 was possible for the LTR fragment. The phylogenetic analysis of LTR sequences of KUW and 34 other HTLV-1 isolates has shown that Kuwaiti HTLV-1 belongs to a cosmopolitan "a" subtype of HTLV-1 and tends to cluster together with HTLV-1 originating from the Mashhad region of Iran. These results suggest that common origin of Mashhadi and Kuwaiti (Najafi) HTLV-1 and the possibility of another pocket of HTLV-1 infection in the Middle East, located in the Najaf region of Iraq.

HIV type 1 subtypes B and C from new regions of India and Indian and Ethiopian expatriates in Kuwait.

PIP: HIV-1 subtype B isolates have previously been described in India only in the state of Andhra Pradesh, while subtype C isolates have been reported as widespread in the Bombay and Goa regions of India. Gag subtype was determined in HIV-1 isolates from six Indians and one Ethiopian. One Indian was a native of Goa residing in Kuwait, and the others were natives of Bihar, Haryana, West Bengal, and New Delhi states. Five subjects were males aged 20-26 years. The remaining two subjects were females aged 34 and 40. Four of the men acquired HIV through sexual transmission; the other man was presumably infected through contaminated blood. Six isolates were identified as subtype C and one as subtype B. These preliminary findings obtained by arranging the HIV-1 gag sequences according to their similarity score were confirmed by cladogram and nested analysis. HIV-1 subtype C isolates are therefore present in Bombay and Goa as well as in other regions of northern and eastern India. The subtype has also infected Indian and Ethiopian expatriates living in Kuwait.^ieng

TaqI polymorphism in the 3' flanking region of the PI gene among Kuwaiti Arabs and Russians.

The Taq1 polymorphism in the 3' flanking region of the PI gene has been reported to be associated with chronic obstructive pulmonary disease (COPD). We have studied the frequency of the Taq1 polymorphism in 117 Kuwaiti Arabs and 110 Russians using PCR/RFLP. The frequency of this polymorphism was found to be 0.235 in the Arabs and 0.027 in the Russians. Such a striking difference in allele frequencies could be due to a 'founder effect' in the Kuwaiti population. However: it may also be that this mutation provides a selective advantage, thus accounting for its fixation at a rather high frequency in some populations. Our results suggest that ethnic composition is a very important factor which should be taken into consideration when studying the association of the Taq1 polymorphism with COPD.