Y HOC VIET NAM THANG - SO 2/2014 tif nhan chii yeu tham gia tiX van HIV tu" nguyen (34,5%) va tu' van d y phong lay truyen HIV tCr me sang ( , % so phdng kham san). Chi 8,3% cac cd sd thyc hien dirpc viec xet nghiem t y nguyen va , % cac phong kham san xet nghiem sang Ipc HIV cho phu n y mang thai. Cong tac dieu tri chii yeu la dieu tri nhiem triing qua du'dng sinh due (18,6%) va nhiem triing cd hpi (14,4%), cac tru'dng hdp khac du'dc chuyen giri (47,3%) va chu'a tham gia dieu tri ARV. Chi mdi khoang tren du'di % cac cd sd y te tu" du'dc tap huan ve phong chdng HIV/AIDS va cd san tai lieu hu'dng dan. Ty le cd sd du'dc cung cap bieu mau, phan hoi thong tin va du'dc giam sat ho trd ky thuat chi dat myc rat thap. V I . KHUYEN NGH! Can tang cu'dng vai tro va nang lyc cua cac cd sd y t u nhan phdng chong HIV/AIDS thong qua viec quy djnh ve chye nang, nhiem vu, xay dyng mo hinh, cung cap thong tin, cap nhat kien thyc ve sang Ipc, tu" van ve HIV/AIDS, xay dyng he thong bieu m l u bao cao, phdi hdp congtu" va tang cu'dng giam sat ho t r d ky thuat. TAI LIEU T H A M KHAO 1. Bg Y te (2013), Bao cao chung tong quan nganh y te nam 2013. Nha xuat ban y hoc. £ Tran Thj Mai Oanh va cong su' (2013), Danh gia thyc trang va de xuat giai phap nham tSng cu'dng phoi hop cong tiT ITnh vyc y te. Viln Chien luoc va chinh sach y te. J. Uy ban thu'dng vu Quoc hoi, Phap lenh ve hanh nghe y dUtfc tu" nhan. 2003. 4. Harvard School of Public Health (2009). An Overview of Public Private Partnerships in Health. 5. Sheikh, K., et al. (2005). Urban private practitioners; potential partners in the care of patients with HIV/AIDS. Natl Med J India,18(l); p. 32-5. 6. Toan K Tran et al. (2012). Factors associated with antenatal care adequacy in rural and urban contexts - results from two health and demographic surveillance sites in Vietnam. BMC Health Services Research, 12:40 7. UNAIDS (2013). UNAIDS report on the global AIDS epidemic 2013. RAN DOC VA DOC TO CUA CAC LOAI RAN DOC TAI VIET NAM Trinh Xuan Kiem*, Tran Thj Ngan**, Le KhSc Quyen* T O M TAT RSn dpc gay nan cho ngu'di van dang la van de y hoc ton tai d cac nirdc nhiet ddi dang phat trien nhU Viet Nam. Tuy nhien, ran dgc d5c trung cho moi viing dja ly khac nhau. Can du'dc nghien ciru, phan loai, xac djnh chirc nang sinh hpc, dpc hpc cac loai rSn dpc co tam quan trpng y hpc tai moi quoc gia. Theo hu'dng dan ciia To chye Y te tlie gidi (WHO) va cac chuyen gia hang dau the gidi, ket qua nghien ciru da xac lap cong hp ran dpc (Hp r§n ho va hp ran luc gom 10 loai) la nguyen nhan thu'dng xuyen gay nan cho ngu'di tai Viet Nam, Lao va Campuchia (Sangl). Dong thdi dSc ti'nh sinh hpc, doc hpc, dac biet lieu doc gay chet 50% (LDso) cua noc tyng loai ran dpc da dirpc xac djnh (Bang 2). 06 clifnh la cO sd khoa hgc eiia cae chiTdng tnnh tiep theo, dac biet che tao huyet khang nge dac hieu, thiet thyc phuc vu cap cyu tren lam sang. Tu'khda: RSn dpc va LD50 SUMMARY VENOMOUS SNAKES AND T H E I R TOXINSIN VIETNAM Venomous snakes of medical importance and snake bites are a big medical problem, but it was neglected in tropical countries such as Vietnam. However, snakes are characterized for each different geographical region of the World. The method for research was applied by WHO guidelines and techniques of the famous international specialists. The results, Elapidae and Viperidae families, content 10 species (Table 1) and their venom's biological and toxicologica! functions with LD50 for each venom were established. (Table 2). The research for recognition of the particular species of greatest medical importance is * Vien nghien c&u phat trien cdng nghe ndng thdn ** bai hoc Y Hal phdng *** Benh vien Viet - Phap TP Hd Chi Minh Phan bi$n khoa hgc: GS.TS Hoang VSn Lu'dng Y H O C V?ET NAM THANG - SO 2/2014 fundamental to the appropriate design of specific antivenoms for Vietnam, Lao and Cambodia. Keywords: Venomous snake & LD50 I. DAT V A N OE Cho den nay, ran can gay nhiem doc, t y vong hoac thu'dng tat suot ddi van la moi hiem hpa cho loai ngu'di. Tai Hpi nghj chong dpc Chau A-Thai Binh Du'dng, Ha Noi, 2010, Chii tich Hoi Dpc Hpc toan cau (1ST), GS Gopalakrishnakone.P da thong bao: "A/o/ nam thi gidi co tdi trieu nan nhan bi ran can, t& vong 125 ngan np&di, 50% sd nan nhan thugc vung Chau A-Thai Binh D&dn^'. Tai Viet Nam, moi nam cd tdi 30 ngan nan nhan ran can. T y vong nhom nan nhan nhiem dpc nang, khong cd thuoc dac trj, len tdi 25% (7). Qiia that, day van la van d ^ y te ton tai cua cac nu'dc nhiet ddi, dang phat trien. Dap litig ddi hdi thyc te do, t y nam 1992, Ddn vj nghien cyu che tao huyet khang npc da dydc Bp Y te cho phep thyc hien nhieu de tai nghien cyu. Trong dd, nghien cu'u dpc t d npc ciia ciia cac loai rSn dpc, nguyen nhan tryc tiep nguy hai cho ngu'di la nghien cyu zd ban, cd vai trd quyet djnh cac tien trinh tiep theo. Tir cd thudc dac trj, an toan va hu'u hieu cyu song nan nhan ran dpc. Ket qua nghien cyu khong chi yng dung tai Viet Nam ma ca nu'dc Dong Du'dng va khu yifc. Od la muc tieu quan trpng hang dau cua nghien cyu: 1. Xac dinh cac loai ran doc nguy hiem bien cho ngu'di tai Viet Nam 2. Xac dmh cac dpc to npc ciia tyng loai ran dpc tai Viet Nam II. P H y O N G PHAP - Tran Kien, Nguyen Quoc Thang: Phan loai hinh thai hpc, djch te hpc va sinh hoc cac loai ran dpc tai Viet Nam, Nha xuat ban KHia",1995.(l) - John Coborn: The Atlas of snakes of the World. Distributed in the United States by T.F.H. Publications, Inc, 1991.(3) - Theakston. D, Tan, Nget Hong: Toxins from venoms of poisonous snakes indigenous to Malaysia, 2011.(5) - Wuster.W: Venomous snake systematics; Implication for snake bite treatment and toxinology. Envenomings and their treatment. 1^ International Congress on Envenomation, 1995. • Warrell D.A: Clinical Toxicology of snakebites in Asia, 1995.(6) - WHO guidelines for the production, control, and regulation of antivenom immunoglobulins. 2008,(7) II. K ! T Q U A V A B A N LUAN . . Ci^c l o ^ i rSn d o c q u a n t r o n g ve y hoc t a i V i e t N a m , Lao, C a m p u c h i a (Snakes of Medical I m p o r t a n c e ) Co hp ran dpc chii yeu va bien tai Viet Nam, Lao va Campuchia: Hp ran ho (Elapidae) "^di loai va hp ran luc (Viperidae) vdi loai. (1,2,3) Bang •Phan loai ran ddc chii /eu, bien tai Viet Nam Ten Khoa hoc TT Ten Tieng Viet Naja atra Ho mang HQ (Family) RSn ho RSn lyc 10 Ho dat Naja kaouthia Dia phu'dng Bac Viet Nam, Lao Tay Nam boVN, Campuchia Ho meo Naja siamensis £)6ng Nam bp-VN, Campuchia Ho chiia Ophiophagus hannah Khap nu'dc VN,Lao,Campuchia Khap nu'dc VN,Lao,Campuchia Cap nong Bungarus fasciatus Cap nia (Bac) Bungarus multicinctus Bac Viet Nam,Lao Capnia(Nam) Bungarus candidus Nam Viet Nam,Campuchia Ran bien Hydrophiidae (sea snakes) Luc xanh Tnmeresurus albolabris Tap trung/ bien Phanthiet Khap nu'dc VN,Lao campuchia Choam quap Calloselasma rhodostoma Oong Nam bpVN,Campuchia Y HOC VIET NAM THANG - SO 2/2014 3.2 Npc cac loai ran doc quan ve y hoc tai Viet Nam 3.2.1. Thanh phan chu yeu cua npc hg ran hd Npc ran ho kho bao gom chii yeu la proteins (70-90%) va mpt so lu'dng nhd kim loai, du'dng, md va cac amin sinh hoc. Proteins noc gom loai, loai cd hoat tinh men va loai khong co hoat tfnh men. a) Dpc td than kinh (NeurotoxinsJ: Noc ciia hp ran ho (cac loai ran ho, ran khoang va ran bien) cd dpc td than kinh gay liet mem toan than, suy hd hap cap, Theo cau triic phan ty ciia dpc to than kinh, chung du'dc chia nhdm: - Nhdm dpc td than kinh thy nhat, (Doc td than kinh chuoi ngan). Dd !a cac chuoi polypeptides co (60-70) gdc amino acid, trpng lu'dng phan ty khPang 7.000, lieu dpc LD50/TM ^'^ # 0,1 pg/g chudt thi nghiem. Hoat tinh: Gay tac (block) dan truyen tin hieu tai khdp (synape) than kinh-cd, khang khy eye than kinh-cd, cdn du'dc gpi la dpc td than kinh hau synape, chiing cd chuoi amino acid rat giong nhau. du'dc mdt vai loai dpc to than kinh tien synape^ npc ran khoang va ran bien Viet Nam.Trong dd, ddc td than kinh chuoi dai (71) goc amino acid la ddc to nguy hiem nhat. b) Dgc tdtim: Npc ran ho cd chya (25-60%) trpng lu'dng npc khd la polypeptide dpc td tim. Ngoai ddc to than kinh, npc hp ran ho cdn chift cac polypeptides hoat ti'nh diTdc hpc khac nhau. ^Ci la cac polypeptides khdng cd hoat tinh men vdi lu'dng phan ty la (6.000-7.000). Ooc to tac dpng tren ca loai te bao de bj kich thfch va khdng de bj kfch thich (excitable & non-excitable cells), gay khy eye khong hoi phuc eiia mang te bao. Hau qua la huy hoai cau true va chye nang cua te bao, Net cd, suy tuan hoan, suy hd hap, roi ngyng tim d ky tam thu. (Systolic arrest). Dpc to tim cd LDs(/TF4 # 1-2 pg/g chuoi thf nghiem.(5,7) 3.2.2. Thanh pii'an chu yiu ciia npc hg ran iuc Men la phan quan trpng cua npc rSn nhat la npc hp ran luc. Men ciia npc ran thay doi theo miia va tudi ran. Vai tro ehu yeu cua men - Nhdm dec td than kinh thy hai, (Dpc to than npc ran la phan hiiy moi. Trong dd, men kinh chuoi dai) gom (> 70) gdc amino acid, cd phospholipase A2 ed tiem nang lam tan v3 hong hoat tinh block t\^r\ kinh-cd bang each tac dong cau tryc tiep, khang ddng, gay chay mau va hoai tren ban tan ciing than kinh van dpng tien ty ed. Men thiiy phan arginine cd hoat tinh synape, du'dc gpi la ddc to than kinh tien synape, thrombin-like, gay hdi chyng phan huy fibrin tren trpng lu'dng phan ty tdi 11.000. Oa phan lap ong nghiem.(2,5) Bang 2: Ket qua xac dinh Lieu chet 50% (LD50 )/TM/chudt ciia npc cae loai ran dpc chu yeu tai Viet Nam, Lao va campuchia LDs„ (jg/g/TM chuot Noc toai ran TT 0,4 Naja kaouthia (Ho dat) 0. hannah (Ho chua) 1,2 B fasciatus (Cap nong) 1,4 B. candidus (Cap nia) 0,1 T.albolabris (Luc xanh duoi do) 0,5 C.rhodostoma (Choam quap) 6,1 TP4'h Tinh m?ch 3.2.3. Npc cua ran ho dat ' Ddc td than kinh hau synape cua noc ho dat chiem 23% trpng lu'dng npc khd, chu yeu la polypeptide chuoi "dai' (71) gdc amino acid. Day la ddc to nguy hiem va quyet djnh nhat, sy khac biet ve dae tinh mien dieh so vdi ddc td than kinh chuoi "'ngad' (62-63) gde amino acid cua cac loai ran hd khac. Chinh nd da quyet dir* tinh ddn dac hieu cua huyet khang npc ho dat, khdng cd phan yng cheo vdi npc cac loa! rSn hd cung hp. - Ddc to tim chiem 45% trpng lu'dng npc kho, chira hoat tfnh dpc lam chet moi. Cd lo^ Y HQC VIET NAM THANG • SO 2/2014 dpc to tim tu'dng tu" giffa cac loai ran hd. LDsoCua ddc t d tim la 1,2 pg/g. - Protein npc ran ho dat cd lu'dng phan t y cao (> 30.000), chiem % trpng lu'dng npc khd, khdng cd tfnh ddc. Hai loai men phospholipase A2, trpng lu'dng phan t y (14.000) chiem 7% tn?ng lu'dng npc khd ed hoat tfnh khang ddng rat yeu va khdng gay chet moi. Ket qua nghien culJ da du'dc minh hoat tren lam sang: Nan nh_an bj nhiem dpc npc ran ho dat chu yeu la nhiem dpc than kinh, cd the t y vong, khdng xuat hien eac trieu chyng rdi loan ddng-cam mau, xet nghiem ddng-cam mau ludn binh thu'dng. Ket qiia nghien cyu thu du'dc t y npc ran ho dat Viet Nam, Campuchia tu'dng t y nhu" ket qua nghien cyu cua Joubert va Taljaard, 1980.(5,7). 3.2.4. Npc cua ran ho chua RSn hd chua la mpt cac loai ran dpc to nhat, dai nhat va nguy hiem nhat tren the gidi.(4,7). - Ddc to than kinh hau synape. Npc ran ho chiia cd loai ddc t d than kinh hau synape, nguy hiem tinh mang, ehiem % trpng lu'dng npc khd. Chuoi peptide chya (73) gdc amino acid, vdi LD50 # 0,2 pg/g/TM chudt. - Men tieu protein (Protease): Chiem 7% trpng lu'dng npc khd. Cd loai men tieu protein . d i loai men deu cd hoat tfnh gay phii ne. Da chiet tach dype men protease gay chay mau, ban chat la metalloprotease, cd diem dang dien (a 5.3, vdi LDso #0,182pg/g/TM thd.(5). Tren lam sang, nan nhan ran ho chua bj phu ne tai cho lan rdng, nhuhg roi toan ddng mau chi thoang qua. (WarellD.A. Clinical Toxicology of snake bites in Asia, 1995). 3.2.5. Npc cua ran cap nong Day la loai ran dpc cd nhieu khoang mau den,xen ke khoang mau vang bao quanh than rSn. Hiem ran can ngu'di, cd the eoi la rSn vo hai. Tuy nhien, cung da cd bao cao ve nan nhan bj nhiem ddc, t y vong ran cap nong. Npc rSn cap nong cd chya ca ddc to tien va hau synapse tlian kinh, vdi LDSO = 1,4 182|jg/g/TM chupt.(l,4) 3.2.6. Npc cua rin cap nia RSn cap nia mien Nam Viet Nam chi cd tdi da 32 khoang den bao quanh mat lu'ng den mat ben than rSn, khoang trSng xen ke bao quanh than, tdi toan bd mat bung. Ran hoat ddng chii yeu vao ban dem, thydng chu ddng can ngu'di tiep xuc. Doc tinh npc rat cao, vdi LDSO # 0,lMg/g/TM chudt. Vi vay, cap nia Nam du'dc coi la loai rSn nguy hiem nhat tren toan the gidi. Tiec thay, cho tdi nay, van chu'a ed huyet khang npc ran cap nia thu'dng mai.(6,7) Tai Viet Nam, t y nam 2000, Ddn vi nghien cu'u ran dpc benh vien Chd Riy da che tao cdng huyet khang npc ran cap nia Nam. Nam 2010, Ddn vi nghien cyu ran ddc benh vien Bach Mai va NCS Thai Danh Tuyen' da che tao cdng huyet khang npc ran cap nia da gia cho ca loai ran cap ma Bac {B.multicinctus) va ran cap nia Nam {B.candidus) 3.2.7. Noc cua ran iuc xanh moi trang, duoi Ran luc xanh mdi trang, dudi dd rat bien tren toan lanh thd nu'dc Viet Nam, Lao, Cmpuchia. Noc ran luc xanh ed hoat tfnh chay mau, tieu sdi td huyet (defibrination), tang hoat tfnh thiiy phan sdi td huyet (fibrinolytic activity), ndi bat la hoat tfnh thrombin va giam tieu eau. Npc ran luc xanh mdi trang cd LDsott 0,5 pg/g/TM chudt.{5) 3.2.8. Npc cua ran choam quap Ran Choam quap ten khoa hoc {Calloselasma rhodostoma), ten tieng Anh (Malayan Pit Viper), xu'a van gpi la Agkistrodon rhodostoma, hoac Ancistrodon rhodostoma. Ran cd mau nau dat dd, dau hinh tam giac rat dac tru'ng. Loai ran rat hoat hda tdi trdi, nhanh nhay tan cdng neu bj quay rdi, la nguyen nhan ran can bien nhat tai mien Ddng Nam bd,Viet Nam, Campuchia. Noc cd cd LD50 # 6,1 MQ/Q/TM. Nghien cyu ran nudi nhdt nhan tao da chyng minh rang sy thay ddi dac tfnh cua noc phu thudc vao chat lieu di truyen hdn la mdi tru'dng. Npc ran Choam quap chya nhieu men cd hoat tinh sinh hpc: ehay mau, men gidng thrombin, phan hiiy filirinogen, ifc che ngu'ng tap tieu cau, gay rdi loan ddng cam mau rat nang ne, hoai t y tai cho lan rpng, xudng tan Idp can-cd, (2,3) Nhffng nam gan day, Huang va cdng sy tai Taiwan, Markland.F, Dai hpc USC, Hoa Ky va nhdm nghien cirli Viet Nam da phan lap du'dc Disintegrin tff npc ran Choam quap cd hoat tfnh khang te bao ung thff. Day cung la ket qua bu'dc dau ciia hdp tac khoa hpc Viet Nam-Hoa Ky nghien cffu che tao thudc dieu trj ung thff t y npc ran Viet Nam. (2) IV. KET LUAN - Oa phan lap cdng hp ran ddc: Hp ran hd {Elapidae)y'a hp ran luc {Viperidae), gom 10 loai ran cd tam quan trpng y hpc tai Viet Nam, Lao va campuchia. 75 Y HOC VIET NAM THANG • SO 2/2014 - Da xac dinh dac tfnh sinh hoc, ddc hpc ciia npc eac loai ran dpc thffdng xuyen gay nan cho ngffdi tai Viet Nam, Lao va Campuchia, vdi lieu chet {LD50 yg/g/TM/)/ chudt ciia npc ran ho dat (0,4), npc ho chiia (1,2), npc cap nong (1,4), npc cap nia Nam (0,1), npc luc xanh mdi trang (0,5) va npc Choam quap (6,1). Day la cd sd khoa hpc can ban gdp phan giai quyet van de y khoa tdn tai, dong thdi md chi/dng trinh ve nghien cffu che tao thudc mdi t y npc ran Viet Nam. TAI LIEU T H A M KHAO 1. Tr^an Kien, Nguyin Quoc Th^ng., 1995. Cac loai ran doc Viet Nam. Nha xuat ban KHKT,7-198. 2. Au.L.C, Huang, Y.B., Huang, T.F., 1991. A common precursor for a putative hemorrhagic protein and rhodostomin, a platelet aggregation inhibitor of the venom of Calloselasma rhodostoma: Molecular cloning and sequence analysis. Biochem. Biophys. Researdi Communications, 181-585. John Coborn., 1991. The Atlas of snakes of the World. Distributed in the United States by T.F.H. Publications, Inc. 1-590. Smith Sonian; A field guide to the snakes of south Vietnam, United States National Museum City of Washington, 1970. Tan, N.H and Fung, SY., 2002. A hemorrhagic toxin from the venom of Tn'meresunis purpureomaculatus snake. European Journal of Biochemistry 269, 99. Warrell, D.A., Looareesuwan, S., Theakston, R.D.G.,1983. Severe neurotoxic envenoming by the Malayan krait Bungarus candidus. response to antivenom and anticholinesterase. British Medical Journal 286:678-680. WHO Guidelines for the production, control, and regulation of antivenom immunoglobulins. 2008, 30-210. NGHIEN CU'U KET QUA TUY DO Of CAC BENH NHAN THIEU MAU Nguyen Thi Minh Phuo'ng*, Tru-ong Thi Thao Hien* TOM TAT Thieu mau la roi loan huyet hpc gap kha thffdng xuyen d tat ca mgi Iffa liuoi. Tuy dong mot vai tro quan trpng chan doan cac nguyen nhan thieu mau. Muc tieu nghien cu'u: danh gia mffc do, phan loai thieu mau va cac roi loan huyet hpc gay thieu mau qua xet nghiem mau ngoai vi va tiiy do. Doi tffdng va phu'dng phap nghien cu'u: nghien cffu hoi cffu ket hdp tien ciTu tren 506 benh nhan (BN) thieu mau dieu tn tai Benh vien TL/QD 108 tff 1/2008 den 12/2013. Kham lam sang va dUOc lam cho tat ca cac BN. Ket qua: thieu mau mffc nhe 42,1%, trung binh 45,6% va n§ng 11,3%. Thieu mau dang sac hong cau (HC) binh thu'dng chiem 59,3%; nhi/pc sac HC nho 34,6% va Uu sac HC to 6,1%. Trong 506 BN thieu mau dUcfc lam tiiy tang smh dong piasmocyte chtem 16,6%. tang smh dong HC chiem 15,2%; giam san dong HC 13,1%. Bach cau cap gap d 16 BN (3,1%) 11 BN bach cau cap va BN bach cau lympho cap. 43,3% thieu mau nhUng tiiy hoan toan binh thi/dng. Ket luan: Tiiy dd la bUdc quan trpng de chan doan nhieu rdi loan huyet hgc gay thieu mau. Tu'khda:Tt\\^u mau, dd SUMMARY STUDY ON BONE MARROW ASPIRATION I N A N E M I C PATIENTS Anemia is hematological disorders that are quite frequent in all age group. Bone Marrow Aspiration plays a major role in the diagnosis of its underlying cause. Objective: To evaluate the grade, classification and the causes of anemia through interpret the blood counts and bone marrow aspiration findings. Materials and Methods: This was a retrospective and prospective study carried out at 108 military central hospital from 1/2008 to 12/2013 on 506 anemic patent, Bone marrow aspiration of all patients was carried out. Results: mild anemia 42,1%, moderate anemia 46,6% and severe anemia 11,3%. Normochromic normocytic anemia 59,3%, microcytc hypochromic 34,6% and Macrocytic hyperchromic 6,1%. Out of 506 anemic patients was performed bone marrow aspiration, plasmocytic hyperplasia was sew m 16,6%, erythroid hyperplasia was seen in 15,2%). erythroid hypoplasia was seen in 13,1%. Acute * Khoa Huyet hoc lam sang Benh vien TWQD 108 Phan bien khoa hgc: PGS.TS VQ Van KhiSn . phu'dng Bac Viet Nam, Lao Tay Nam boVN, Campuchia £)6ng Nam bp-VN, Campuchia Khap nu'dc VN,Lao,Campuchia Khap nu'dc VN,Lao,Campuchia Bac Viet Nam, Lao Nam Viet Nam, Campuchia Tap. "A/o/ nam thi gidi co tdi 5 trieu nan nhan bi ran can, t& vong 125 ngan np&di, 50% sd nan nhan nay thugc vung Chau A-Thai Binh D&dn^'. Tai Viet Nam, moi nam cd tdi. nu'dc VN,Lao campuchia Oong Nam bpVN,Campuchia Y HOC VIET NAM THANG 2 - SO 2/2014 3.2 Npc cac loai ran doc quan trong ve y hoc tai Viet Nam 3.2.1. Thanh phan chu yeu cua