Gel filtration of bacterial cell extract

Так как от остатков гомогенизированных клеток легко отделить растительные вирусы (Steere и Qckers, 1962; ?ech, 1962) и митохондрии (Hjertén, 1962), мы сделали попытку использовать этот простой метод и для отделения рибосом. Надосадок гомогената растущих клеток Bacillus megaterium 110 наносили на столбец 3% гранулированного агара (Polson, 1961) и промывали 66 мл буферного раствора Tris (pH 7,72, 0,005 M с 0,01 M?MgCl₂) в течение часа при комнатной температуре. В элюате определяли абсорбцию при 260 мμ и белки (рис. 1). При ультрацентрифугировании образца были обнаружены рибосомы с S ₂₀ ⁰ 107, 71, 5, 45 и 30S (рис. 2). Ультрацентрифугированием фракции № 10 были с помощью адсорбции в УФ лучах найдены рибосомы с s ₂₀ ⁰ 107 и 44,6S (рис. 3). Группа 100S перекрывалась абсорбцией рибосом 70S, группа 30 не была обнаружена. Отделение рибосом как самостоятельной вершины не было получено. Однако, судя по соотношению нуклеиновых кислот и белков во главе вымываемой плазмы (где присутствует только РНК), здесь имела место концентрация практически чистых рибосом, как подтверждает и седиментация. ДНК удавалось определить только во фракциях второй половины элюата плазмы (рис. 4).     

Bacterial release of oil

Были произведены исследования изменений активности микрофлоры залежи по площади и во времени в трех нефтеносных областях после инъекции питательных веществ (мелассовая барда) в залежь. В опытах прослеживали количество десульфурирующих бактерий в пластвовой воде, извлекаемой из залежи одновременно с нефтью. О проникновении питательных веществ из нагнетательной скважины в эксплуатационные скважины судили на основании доказуемого размножения десульфурирующих бактерий в воде эксплуатационных скважин после инъекции (табл. 1, 2, 3). Для определения периода, необхоимого для проникновения питательных веществ, исходили из кривых размножения десульфурирующих бактерий, на основании которых определяли «время среднего размножения» (MPT) для отдельных эксплуатационных скважин (рис. 1). На основе «времени среднего размножения» и расстояния от нагнетательной скважин вычисляли среднюю скорость проникновения питательных веществ через коллектор в данном направлении от нагнетательной скважин. Полученные таким образом величины применяли для построения карт (рис. 2, 4, 5). В первом опыте в залежи Петрова Весь было установлено, что в районе скважин № 429 и 430 наблюдается запаздывание проникновения питательных веществ, тогда как в районе скважин № 421, 427 и 402 проникновение является наиболее быстрым. При сравнении с картой проницаемости (рис. 3) оказывается, что эти области перекрываются с областями максимальной и минимальной проницаемости коллектора. При втором опыте в залежи Петрова Весь на основании полученных результатов было установлено, какие сбросы проявляются как уплотняющий элемент и какие не представляют препятствия. Результаты опыта в залежи Годонин показали расположение дренажей, которые образовались в коллекторе в течение многолетней эксплуатации. Собственной целью поставленных опытов было установить, в каких эксплуатационных скважинах размножение десульфурирующих бактерий усилилось после инъекции питательных веществ, а также—в какой период это влияние проявилось. Так как эта цель была достигнута, теперь можно будет произвести более точную оценку влияния размножения десульфирующих бактерий на добычу нефти: будет возможно исключить из опыта по оценке добычи те скважины, в которых не наблюдалось влияние на активность десульфурирующих бактерий, и при дальнейшей оценке добычи сосредоточить свое внимание на периоды повышенной микробиологической активности в области скважины. Кроме того обнаружилось, что микробиологические показания относительно проникновения питателяных веществ можно использовать для определения связи между нагнетательной скважиной и эксплуатационими скважинами. При оценке скорости проникновения питательных веществ от нагнетательной скважини можно определить также направление наиболее быстрого и наиболее медленного распространения и на основании этого судить о проницаемости коллектора в различных направлениях.     

Geomicrobiological oil prospection

лсследовалась чувствительность углеродородиыx бактерий к различным концептрациям углеволородныx гзов в ат мос?ере почвы над дяумя месторожценпвми не?ти.Культуры бактерии, окислвюшиx метаи, зтан ипроиан, подвергали действиы газообразныx углеволородов в мелкиx скважинаx в исследуемой области. Рост метановых бактерий определйли практически во всех скважинах, и степень их раэмножения в отдельных случаях колебалась мало (1-3. 10⁷). Наоборот, раэмножение бактерий, окисляющих более высокие углеводороды, обнаруживало эаметные раэличия (табл. 1, 2). – лэ сравнения с данными химического определения углеводородных гаэов вытекает, что по раэвитию пропановых бактерий воэможно раэличить концентрацию высшпх гаэообраэных углеводородов в пределах от 10^-5 до 10^-4% объема (рис. 6). Для картогра?ической обработки и сравнения с расположением эалежи не?ти можно было испольэовать только покаэатели раэмножения этановых и полпаговых бактерий (рис. 2, 4). При этой оценку в обоих очагах было отмечено принципальное сходство минимумов бактерий с расположением месторождений не?ти (“halo-effect”). Чувствительность бактерий, лктсдяющих высшие углеводородные гаэы, окаэывается достаточной для распоэнавания концентрации гаэообраэных рад месторождением не?ти и вне его.     

The influence of the soil structure and moisture content on the number of bacteria and the degree of nitrification

ИзгчалоAЬ одноврeмeнноe дeйствиe сBрCкСC@ы поGвKi и Aодeрeа влаBи на количe бактeрий и интeнсивноAтЬ нитрифика. ции в гумуA-карбонаBной почвe. Путeм просeиваниHя образцоCпочвы чeрeз сиBа были в044B;цeлeны слeдующиe фракции: I — агрeгaаты мeнЬшe 1 мм; II — агрeгаты размe@ами в 1—2; мм; III — аг@eгаты размeрами в 2—3 мм; IV — агтeгаBы размeрами в 3—4 мм; V — агрeгаBы размeрами в 4—5 мм. Образцы брали три @аза а год. Для опрeДeлeния количeства бактeрий полЬзовалисЬ прямым мeтодeм флуорeсцeнтной м0438;H043A;H0440;H043E;скопии по Strugger в модификации по Seifert. Пeрeд опрeдeлeниeм биогeнности образцы насыщли влагой до заранee установлeнного уровня и инкCбировали 48 час. при тeмпeратгрe 20° С Нитрификацию опрeдeлOли послe 14-днeвной ?нкгбации образFов, насKщeнных влвгой до опрeдeлeнного уровня и хранившихся в тeрмостатe пр? 20° А. Бы;ло установлeно, что количeство бактeрий зависит от содeржания влаги и 043F;очти нe зависит оB размeров агрeгатов (рис. 1). ИнтeнсивностЬ нитрификации зависит как от содeржаниO влаги, так ? оB размeров агр;eгатов. НаиболЬHая интeнсивностЬ наблюдаласЬ в слу чаe агрeгатов пe@вой фракции, т. e. при диамeтрах мeнЬHe 1 мм. С гвeличeниeм диамeтров агрeгатов интeнсивностЬ нитрификации постeпeнно поннжаласЬ (@ис. 2). Понижeниe интeнсивности нитрификации отличалосЬ опрeдeлCнной правилЬностЬю, инаосновании ee анализа мы пришли к выводу, что инBeнсивностЬ нитрификаFии прямо пропорFионадЬна вeдиGинe спeцифичeAкой повeрхносBи агрeгатов. ДоказатdдЬство зтого привeдeно на рис. З. Для протeрки того, как на интeнсивносBЬ нитрификации дeйствуeт радмeлЬчeниe агрeгатов, мы поставнди опыт, при котором апрeгаBы V фракции были размeлЬчeны до размeров I фракции. Послe измeлЬчeниO интeнсивностЬ ниBририкаFии знаGиBeлЬно повысиласЬ (рис. 4).     

Undertreatment of hypertension and the risk of stroke in the oldest old

The benefit of pharmacological treatment of hypertension in the prevention of cardiovascular diseases has been established mainly in subjects younger than 80 years of age. The consequences of undertreatment of hypertension with regard to the occurrence of stroke was studied in the Netherlands. About 33% of the hypertensives younger than 80 years and 55% of the hypertensives older than 80 years were not pharmacologically treated, although they were 'candidates' for pharmacological treatment of hypertension. About 19% (n = 1350) of all strokes that occurred in the Netherlands in 1994 among hypertensives younger than 80 years may be attributable to untreated hypertension. Among hypertensives older than 80 years this percentage was 32% (n = 1345). Although the benefit of pharmacological treatment of hypertension in persons older than 80 years has not been established experimentally, the results suggest that a considerable proportion of the strokes among this group of hypertensives may be prevented.     

Energy enzymes from the flight muscle of the house sparrow, Passer domesticus-II. Physical and chemical properties related to purification of the glycolytic enzymes

The isoelectric points (pI0), molecular weights and ammonium sulfate precipitation ranges for most of the glycolytic enzymes from house sparrow (Passer domesticus) flight muscle were determined. The pI0 for each enzyme is as follows: HK (6.8), PGI (6.7), PFK (5.4), Ald (7.2), TPI (7.5), PGK (7.1), PGM (6.1), Enol (6.2), PyK (6.6), and LDH (8.3). The molecular weight for each enzyme is as follows: PGI (145,000), Ald (160,000), TPI (60,000), PGK (35,000), PGM (60,000), Enol (100,000), PyK (200,000), and LDH (145,000). The ammonium sulfate precipitation range for each enzyme is as follows: PGI (0-80%), PFK (40-50%), Ald (40-65%), TPI (30-90%), PGK (70-90%), PGM (30-80%), Enol (45-80%), PyK (55-85%), and LDH (40-65%).     

The effect of heavy- vs. light-load jump squats on the development of strength, power, and speed

The purpose of this investigation was to examine the effect of an 8-week training program with heavy- vs. light-load jump squats on various physical performance measures and electromyography (EMG). Twenty-six athletic men with varying levels of resistance training experience performed sessions of jump squats with either 30% (JS30, n = 9) or 80% (JS80, n = 10) of their one repetition maximum in the squat (1RM) or served as a control (C, n = 7). An agility test, 20-m sprint, and jump squats with 30% (30J), 55% (55J), and 80% (80J) of their 1RM were performed before and after training. Peak force, peak velocity (PV), peak power (PP), jump height, and average EMG (concentric phase) were calculated for the jumps. There were significant increases in PP and PV in the 30J, 55J, and 80J for the JS30 group (p 相似文献   

Partial purification and characterization of an endothelial cell growth regulator from the bovine ovary

An inhibitor of endothelial cell thymidine incorporation in vitro was partly purified from cow ovaries using ammonium sulphate (AS) precipitation. Supernatant fluid from the 100,000 g pellet of freshly homogenized ovaries was subjected to stepwise AS precipitation. Precipitates were collected sequentially at 40%, 60%, 80% and 95% saturation, and then each was dissolved, dialysed (Mr 8000 cutoff) and examined in tissue culture for effects on cellular thymidine incorporation by cow pulmonary artery endothelial cells (CPAE) and mouse fibroblasts (L929 and 3T3). The 80% AS precipitate (ppt.) inhibited the in-vitro uptake of [3H]thymidine by CPAE and L929 cells, but not 3T3 cells. Heparin-Sepharose (HS) chromatography of the 80% AS ppt. revealed that the inhibitory activity on CPAE and L929 cells did not bind to HS; the inhibitory fraction was found in the HS column breakthrough (80% BT). The 80% BT fraction reduced CPAE[3H]thymidine uptake as determined by autoradiography and increased cellular uptake of trypan blue. Serial fractions from Sephacryl S-200 exclusion chromatography of the 80% BT contained CPAE inhibitory activity in the Mr range 30,000-50,000. The inhibitory activity on endothelial cells and L929 fibroblasts and the non-reduced molecular weight range of that fraction are similar to those of tumour necrosis factor alpha (TNF alpha). The results indicate that the cow ovary contains a fraction that inhibits endothelial cell growth in vitro and may have important roles in follicular atresia and luteal regression.     

Modification of surface properties of biomaterials influences the ability of Candida albicans to form biofilms

Candida albicans biofilms form on indwelling medical devices (e.g., denture acrylic or intravenous catheters) and are associated with both oral and invasive candidiasis. Here, we determined whether surface modifications of polyetherurethane (Elasthane 80A [E80A]), polycarbonateurethane, and poly(ethyleneterephthalate) (PET) can influence fungal biofilm formation. Polyurethanes were modified by adding 6% polyethylene oxide (6PEO), 6% fluorocarbon, or silicone, while the PET surface was modified to generate hydrophilic, hydrophobic, cationic, or anionic surfaces. Formation of biofilm was quantified by determining metabolic activity and total biomass (dry weight), while its architecture was analyzed by confocal scanning laser microscopy (CSLM). The metabolic activity of biofilm formed by C. albicans on 6PEO-E80A was significantly reduced (by 78%) compared to that of biofilm formed on the nonmodified E80A (optical densities of 0.054 +/- 0.020 and 0.24 +/- 0.10, respectively; P = 0.037). The total biomass of Candida biofilm formed on 6PEO-E80A was 74% lower than that on the nonmodified E80A surface (0.46 +/- 0.15 versus 1.76 +/- 0.32 mg, respectively; P = 0.003). Fungal cells were easily detached from the 6PEO-E80A surface, and we were unable to detect C. albicans biofilm on this surface by CSLM. All other surface modifications allowed formation of C. albicans biofilm, with some differences in thearchitecture. Correlation between contact angle and biofilm formation was observed for polyetherurethane substrates (r = 0.88) but not for PET biomaterials (r = -0.40). This study illustrates that surface modification is a viable approach for identifying surfaces that have antibiofilm characteristics. Investigations into the clinical utility of the identified surfaces are warranted.     

Selective Neurotoxic Lesions of Descending Serotonergic and Noradrenergic Pathways in the Rat

The ability of neurotoxic substances to induce selective lesions of the descending monoaminergic pathways in rats was investigated. Saline, 6-hydroxydopamine, 5,6-dihydroxytryptamine, or 5,7-dihydroxytryptamine were administered into the lumbar subarachnoid space through a chronically indwelling catheter. The lesions were evaluated 2-3 weeks later by in vitro uptake of [3H]noradrenaline and [14C]5-hydroxytryptamine into synaptosomal preparations from the frontal cortex, brainstem, cervical spinal cord, and lumbar spinal cord of each animal. There was no difference in uptake between saline-injected and noncatheterized controls and no significant changes in cortical uptake after any of the treatments (dose range of neurotoxins: 0.6-80 micrograms). In the lumbar spinal cord, 6-hydroxydopamine (5-80 micrograms) reduced the [3H]noradrenaline uptake by approximately 90% with no effects on [14C]5-hydroxytryptamine uptake, whereas 5,6-dihydroxytryptamine reduced the uptake of [14C]5-hydroxytryptamine by 90% (20-80 micrograms). [3H]Noradrenaline uptake was unaffected by lower doses of 5,6-dihydroxytryptamine but fell by 45-55% after 40-80 micrograms. 5,7-Dihydroxytryptamine (10-80 micrograms) reduced [3H]noradrenaline uptake by 90-95% and [14C]5-hydroxytryptamine uptake by approximately 80% (5-80 micrograms) in the lumbar cord. It is concluded that intrathecal administration of suitable doses of neurotoxins may produce extensive selective lesions of descending noradrenergic and serotonergic pathways.     

Fixed-time artificial insemination of postpartum beef cows at 72 or 80 h after treatment with the MGA Select protocol

The objective was to determine the appropriate timing of fixed-time artificial insemination (AI) following administration of the MGA Select protocol. Cows at two locations (Location 1, n=114; Location 2, n=97 ) were assigned to fixed-time AI at 72 or 80 h by age, body condition score (BCS), days postpartum (DPP), AI technician, and sire. All cows were synchronized with the MGA Select protocol, consisting of oral administration of melengestrol acetate (MGA; 0.5mg/hd per day) for 14 days, GnRH (Cysotrelin, 100 microg, i.m.; Day 26) 12 days after MGA withdrawal, followed in 7 days with PGF(2alpha) (PG; Lutalyse, 25mg i.m.; Day 33). Cows were inseminated at 72 h ( n=108 ) or 80 h ( n=103 ) after PG and GnRH (100 microg) was given at insemination. Location was not significant and, therefore, was removed from the model. Mean BCS ( 5.2+/-0.1, 72 h; 5.3+/-0.1, 80 h) and DPP ( 34+/-2, 72 h; 35+/-2, 80 h) did not differ ( P>0.1 ) between treatments. Serum progesterone concentrations 7 and 1 day prior to MGA were used to determine pre-treatment cyclicity: cows with at least one sample with progesterone > or =1 ng/ml were defined as cyclic (33/108, 31%, 72 h, versus 32/103, 31%, 80 h; P>0.1). Cows with serum progesterone concentrations > or =1 ng/ml on the day of PG were defined as responding to the synchronization protocol (74/108 (69%), 72 h versus 69/103 (67%), 80 h; P>0.1 ). Although pregnancy rates were higher ( P<0.05 ) for cows inseminated at 72 h (69/108, 64%) versus 80 h (52/103, 50%) after PG, pregnancy rates at the end of the breeding season did not differ ( P>0.1 ) between treatments (98/108 (91%), 72 h; 88/103 (85%), 80 h). In conclusion, pregnancy rates were higher when postpartum beef cows synchronized with the MGA Select protocol were inseminated at 72 h versus 80 h after PG.     

The hirudin-binding site of human alpha-thrombin. Identification of lysyl residues which participate in the combining site of hirudin-thrombin complex

Chemical modification of 6 lysyl residues within the B-chain of alpha-thrombin was decreased on binding of equal molar hirudin, a thrombin-specific inhibitor. They are Lys-B21 (87% protected), Lys-B52 (80%), Lys-B65 (greater than 95%), Lys-B106 (71%), Lys-B107 (71%), and Lys-B154 (80%). The data suggest that these lysyl residues are situated within or in close proximity to the hirudin-binding site of human alpha-thrombin.     

Porcine IVF embryo development and estrogen receptors are influenced by the concentration of percoll gradients during sperm selection

This study aimed to evaluate the effect of three different concentrations of discontinuous gradients of percoll (90/45, 80/40, and 70/35) in the outcome of porcine in vitro fertilization (IVF) and its influence on further embryo development and quality. Embryo viability was assessed by the expression of estrogen receptors (E₂R) and cleaved caspase‐3 (CC3). The highest percoll concentration (90/45) resulted in the lowest embryo production (24.9%) in comparison with 80/40 (37.5%) and 70/35 (40.0%), with the production being similar between the two lowest concentrations. The hatching rate for 90/45 (26.2%) was lower than for 80/40 (45.5%), and both were similar to the Group 70/35 (32.9%). The hatched embryos from the concentration 90/45 showed the lowest proportion of E₂R expression (3.6%), while the Groups 80/40 (22.6%) and 70/35 (39.3%) had a similar proportion of expression. The live embryos that did not hatch until Day 8 of culture presented a higher CC3 proportion for Group 90/45 (18.3%), in comparison with 80/40 (12.7%) and 70/35 (10.7%), with the latter two being similar. In conclusion, adjustments in percoll concentration used for sperm selection before porcine IVF can improve embryo production and competence for pregnancy recognition and establishment.     

Changes in DNA base sequences in the mutant of Arabidopsis thaliana induced by low-energy N+ implantation

Arabidopsis thaliana (L.) Heynh has many advantages for genome analysis, including a short generation time, small size, large number of offspring, and a relatively small nuclear genome in comparison to other angiosperms and contains a low proportion of repetitive DNA comparatively. Furthermore, the analysis of the completed genome sequence of A. thaliana has been reported[1]. Low-energy ion implantation has attracted more and more attention from researchers in China and Japan since recent s…     

Methods for the recovery of a model virus from healthcare personal protective equipment

Aims:  To develop methods for recovering a model virus (bacteriophage MS2) from healthcare personal protective equipment (PPE).
Methods and Results:  Nine eluents were evaluated for recovery of infectious MS2 from PPE: 1·5% beef extract (BE) pH 7·5 with and without 0·1% Tween 80, 1·5% BE pH 9·0 with and without 0·1% Tween 80, 3% BE pH 7·5 with and without 0·1% Tween 80, 3% BE pH 9·0 with and without 0·1% Tween 80 and PBS with 0·1% Tween 80. Methods were applied to experimentally contaminated PPE. Elution followed by two-step enrichment assay could recover virus inputs as low as 1·5 log₁₀, and could recover >90% of inoculated virus from used items of experimentally contaminated PPE worn by human volunteers.
Conclusions:  BE was effective for recovering infectious viruses from a range of PPE materials.
Significance and Impact of the Study:  PPE plays a crucial role in interrupting transmission of infectious agents from patients to healthcare workers (HCWs). The fate of micro-organisms when PPE is removed and disposed of has important consequences for infection control. Methods described here can be used to conduct rigorous studies of viral survival and transfer on PPE for risk assessments in infection control and HCW protection.     

Studies on the Microbiological Transformation of Steroids

The microbiological reduction of the 20-carbonyl group of steroids has been investigated. Candida pulcherrima IFO 0964 and Sporotrichum gougeroti IFO 5982 converted the following substrates into the corresponding 20β-hydroxy derivatives (yields of the products are indicated in parentheses): Reichstein’s Compound S (60~70%) and 17α,21-dihydroxypregna-l,4-diene- 3,20-dione (40~80%). Rhodotorula glutinis IFO 0395 converted the following substrates into the corresponding 20α-hydroxy derivatives: Reichstein’s Compound S (65%), 17 α,21-dihydroxy- pregna-l,4-diene-3,20-dione (80%), llβ,l7α-dihydroxypregn-4-ene-3,20-dione (45%) and 17α, 19,21 -trihydroxypregn-4-ene-3,20-dione (10%).     

Effect of Tween 80 on the production of curdlan by Alcaligenes faecalis ATCC 31749

This study aims to investigate the effects of Tween 80 on curdlan production, cell growth, and glucosyltransferase activity. The addition of Tween 80 to the culture medium increased curdlan production. However, curdlan production did not increase further when excessive Tween 80 (>0.3% Tween 80) was added to the culture medium. The addition of Tween 80 to the culture medium did not affect cell growth. The glucosyltransferase activity involved in the curdlan synthesis increased with the increase of Tween 80 concentration. The glucosyltransferase activity did not increase further when excessive Tween 80 (>0.3% Tween 80) was added to the culture medium. Maximum curdlan was observed at day 5 and then levelled off. The biomass continued to increase until the end of the experimental period (6 d). Maximum glucosyltransferase activity was also observed at day 5 and decreased thereafter. The results indicate that the enhanced curdlan production by Tween 80 is highly correlated with glucosyltransferase activity.     

Non-invasive characterization of single motor unit electromyographic and mechanomyographic activities in the biceps brachii muscle.

The aim of the study was to investigate amplitude and frequency content of single motor unit (MU) electromyographic (EMG) and mechanomyographic (MMG) responses. Multi-channel surface EMG and MMG signals were detected from the dominant biceps brachii muscle of 10 volunteers during isometric voluntary contractions at 20%, 50%, and 80% of the maximal voluntary contraction (MVC) force. Each contraction was performed three times in the experimental session which was repeated in three non-consecutive days. Single MU action potentials were identified from the surface EMG signals and their times of occurrence used to trigger the averaging of the MMG signal. At each contraction level, the MUs with action potentials of highest amplitude were identified. Single MU EMG and MMG amplitude and mean frequency were estimated with normalized standard error of the mean within subjects (due to repetition of the measure in different trials and experimental sessions) smaller than 15% and 7%, respectively, in all conditions. The amplitude of the action potentials of the detected MUs increased with increasing force (mean +/- SD, 244 +/- 116 microV at 20% MVC, and 1426 +/- 638 microV at 80% MVC; P < 0.001) while MU MMG amplitude increased from 20% to 50% MVC (40.5 +/- 20.9 and 150 +/- 88.4 mm/s(2), respectively; P<0.001) and did not change significantly between 50% and 80% MVC (129 +/ -82.7 mm/s(2) at 80% MVC). MU EMG mean frequency decreased with contraction level (20% MVC: 97.2 +/- 13.9 Hz; 80% MVC: 86.2 +/- 11.4 Hz; P < 0.001) while MU MMG mean frequency increased (20% MVC: 33.2 +/- 6.8 Hz; 80% MVC: 40.1 +/- 6.1 Hz; P < 0.001). EMG peak-to-peak amplitude and mean frequency of individual MUs were not correlated with the corresponding variables of MMG at any contraction level.     

Ratings of perceived exertion and muscle activity during the bench press exercise in recreational and novice lifters

This study examined ratings of perceived exertion (RPE) and electromyography (EMG) during resistance exercise in recreational and novice lifters. Fourteen novice (age = 21.5 +/- 1.5 years) and 14 recreationally trained (age = 21.9 +/- 2.2 years) women volunteered to perform the bench press exercise at 60 and 80% of their 1 repetition maximum (1RM). RPE and EMG were measured during both intensities. Statistical analyses revealed that active muscle RPE increased as resistance exercise intensity increased from 60% 1RM to 80% 1RM (12.32 +/- 1.81 vs. 15.14 +/- 1.74). Integrated EMG also increased as resistance exercise intensity increased from 60% 1RM to 80% 1RM (in the pectoralis major; 98.62 +/- 17.54 vs. 127.98 +/- 29.02). No significant differences in RPE or EMG were found between novice and recreational lifters. These results indicate that RPE is related to the relative exercise intensity lifted as well as muscle activity during resistance exercise for both recreational and novice lifters. These results support the use of RPE as a method of resistance exercise intensity estimation for both types of lifters.