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Corresponding Reduction (corresponding + reduction)
Selected AbstractsElevated air temperature alters an old-field insect community in a multifactor climate change experimentGLOBAL CHANGE BIOLOGY, Issue 4 2009SHAWN N. VILLALPANDO Abstract To address how multiple, interacting climate drivers may affect plant,insect community associations, we sampled insects that naturally colonized a constructed old-field plant community grown for over 2 years under simultaneous CO2, temperature, and water manipulation. Insects were sampled using a combination of sticky traps and vacuum sampling, identified to morphospecies and the insect community with respect to abundance, richness, and evenness quantified. Individuals were assigned to four broad feeding guilds in order to examine potential trophic level effects. Although there were occasional effects of CO2 and water treatment, the effects of warming on the insect community were large and consistent. Warming significantly increased Order Thysanoptera abundance and reduced overall morphospecies richness and evenness. Nonmetric multidimensional scaling found that only temperature affected insect community composition, while a Sørensen similarity index showed less correspondence in the insect community between temperature treatments compared with CO2 or soil water treatments. Within the herbivore guild, elevated temperature significantly reduced richness and evenness. Corresponding reductions of diversity measures at higher trophic levels (i.e. parasitoids), along with the finding that herbivore richness was a significant predictor of parasitoid richness, suggest trophic-level effects within the insect community. When the most abundant species were considered in temperature treatments, a small number of species increased in abundance at elevated temperature, while others declined compared with ambient temperature. Effects of temperature in the dominant insects demonstrated that treatment effects were limited to a relatively small number of morphospecies. Observed effects of elevated CO2 concentration on whole-community foliar N concentration did not result in any effect on herbivores, which are probably the most susceptible guild to changes in plant nutritional quality. These results demonstrate that climatic warming may alter certain insect communities via effects on insect species most responsive to a higher temperature, contributing to a change in community structure. [source] The paradox of normal serum albumin in anorexia nervosa: A case reportINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2005Mori J. Krantz MD Abstract Objective Anorexia nervosa (AN) is associated with marked decreases in caloric intake and a corresponding reduction in body weight due to abnormal self body image. Although counterintuitive, hypoalbuminemia and vitamin deficiencies are not expected consequences of this disorder. Etiologic considerations for hypoalbuminemia are discussed. Method The case report of a patient with AN and marked hypoalbuminemia is presented and a focused literature review is reported. Results Hypoalbuminemia was initially attributed to starvation. However, occult infection was ultimately responsible. Serum albumin concentration normalized with antibiotic therapy despite minimal restoration of body weight. Discussion Hypoalbuminemia should not be considered a characteristic feature of AN even in the setting of progressive weight loss. The presence of other potentially life-threatening conditions should be sought, as reduced serum albumin concentration is a marker of inflammation in AN. © 2005 by Wiley Periodicals, Inc. [source] Sodium valproate inhibits glucose transport and exacerbates Glut1-deficiency in vitroJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 4 2005Hei Yi Wong Abstract Anticonvulsant sodium valproate interferes with brain glucose metabolism. The mechanism underlying such metabolic disturbance is unclear. We tested the hypothesis that sodium valproate interferes with cellular glucose transport with a focus on Glut1 since glucose transport across the blood-brain barrier relies on this transporter. Cell types enriched with Glut1 expression including human erythrocytes, human skin fibroblasts, and rat astrocytes were used to study the effects of sodium valproate on glucose transport. Sodium valproate significantly inhibited Glut1 activity in normal and Glut1-deficient erythrocytes by 20%,30%, causing a corresponding reduction of Vmax of glucose transport. Similarly, in primary astrocytes as well as in normal and Glut1-deficient fibroblasts, sodium valproate inhibited glucose transport by 20%,40% (P,<,0.05), accompanied by an up to 60% downregulation of GLUT1 mRNA expression (P,<,0.05). In conclusion, sodium valproate inhibits glucose transport and exacerbates Glut1 deficiency in vitro. Our findings imply the importance of prudent use of sodium valproate for patients with compromised Glut1 function. J. Cell. Biochem. © 2005 Wiley-Liss, Inc. [source] Reference ranges for umbilical vein blood flow in the second half of pregnancy based on longitudinal dataPRENATAL DIAGNOSIS, Issue 2 2005Ganesh Acharya Abstract Objectives To construct new reference ranges for serial measurements of umbilical vein (UV) blood flow. Methods Prospective longitudinal study of blood flow velocities and diameter of the UV measured at four-weekly intervals during 19 to 42 weeks' gestation in 130 low-risk singleton pregnancies. Regression models and multilevel modeling were used to construct the reference ranges. Results On the basis of 511 sets of longitudinal observations, we established new reference percentiles of UV diameter, blood flow velocities, volume flow, and blood flow normalized for fetal weight and abdominal circumference. They reflected some of the developmental patterns of previous cross-sectional studies, but with important differences, particularly near term. The UV blood flow showed a continuous increase until term, whereas the flow normalized per unit fetal weight, a corresponding reduction. Calculating the blood flow on the basis of intensity-weighted mean velocity or 0.5 of the maximum velocity gave almost interchangeable results for most fetuses. Conclusion New reference ranges for UV blood flow based on longitudinal observations appear slightly different from cross-sectional studies, and should be more appropriate for serial evaluation of fetal circulation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Closing the mass balance at chlorinated solvent sites: Sources and attenuation processesREMEDIATION, Issue 2 2010Roopa Kamath Using detailed mass balance and simple analytical models, a spreadsheet-based application (BioBalance) was developed to equip decision makers with a predictive tool that can provide a semiquantitative projection of source-zone concentrations and provide insight into the long-term behavior of the associated chlorinated solvent plume. The various models were linked in a toolkit in order to predict the composite impacts of alternative source-zone remediation technologies and downgradient attenuation processes. Key outputs of BioBalance include estimates of maximum plume size, the time frame for plume stabilization, and an assessment of the sustainability of anaerobic natural attenuation processes. The toolkit also provides spatial and temporal projections of integrated contaminant flux and plume centerline concentrations. Results from model runs of the toolkit indicate that, for sites trying to meet traditional, "final" remedial objectives (e.g., two to three orders of magnitude reduction in concentration with restoration to potable limits), "dispersive" mechanisms (e.g., heterogeneous flow and matrix diffusion) can extend remedial time frames and limit the benefits of source remediation in reducing plume sizes. In these cases, the removal of source mass does not result in a corresponding reduction in the time frame for source remediation or plume stabilization. However, this should not discourage practitioners from implementing source-depletion technologies, since results from the toolkit demonstrate a variety of measurable benefits of source remediation. Model runs suggest that alternative, "intermediate" performance metrics can improve and clarify source remediation objectives and better monitor and evaluate effectiveness. Suggested intermediate performance metrics include reduction in overall concentrations or mass within the plume, reduction of flux moving within a plume, and reduction in the potential for risk to a receptor or migration of a target concentration of contaminant beyond a site boundary. This article describes the development of two key modules of the toolkit as well as illustrates the value of using intermediate performance metrics to evaluate the performance of a source-remediation technology. © 2010 Wiley Periodicals, Inc. [source] Political Competition and Ethnic Identification in AfricaAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 2 2010Benn Eifert This article draws on data from over 35,000 respondents in 22 public opinion surveys in 10 countries and finds strong evidence that ethnic identities in Africa are strengthened by exposure to political competition. In particular, for every month closer their country is to a competitive presidential election, survey respondents are 1.8 percentage points more likely to identify in ethnic terms. Using an innovative multinomial logit empirical methodology, we find that these shifts are accompanied by a corresponding reduction in the salience of occupational and class identities. Our findings lend support to situational theories of social identification and are consistent with the view that ethnic identities matter in Africa for instrumental reasons: because they are useful in the competition for political power. [source] On the mechanisms that limit oxygen uptake during exercise in acute and chronic hypoxia: role of muscle massTHE JOURNAL OF PHYSIOLOGY, Issue 2 2009José A. L. Calbet Peak aerobic power in humans () is markedly affected by inspired O2 tension (). The question to be answered in this study is what factor plays a major role in the limitation of muscle peak in hypoxia: arterial O2 partial pressure () or O2 content ()? Thus, cardiac output (dye dilution with Cardio-green), leg blood flow (thermodilution), intra-arterial blood pressure and femoral arterial-to-venous differences in blood gases were determined in nine lowlanders studied during incremental exercise using a large (two-legged cycle ergometer exercise: Bike) and a small (one-legged knee extension exercise: Knee) muscle mass in normoxia, acute hypoxia (AH) () and after 9 weeks of residence at 5260 m (CH). Reducing the size of the active muscle mass blunted by 62% the effect of hypoxia on in AH and abolished completely the effect of hypoxia on after altitude acclimatization. Acclimatization improved Bike peak exercise from 34 ± 1 in AH to 45 ± 1 mmHg in CH (P < 0.05) and Knee from 38 ± 1 to 55 ± 2 mmHg (P < 0.05). Peak cardiac output and leg blood flow were reduced in hypoxia only during Bike. Acute hypoxia resulted in reduction of systemic O2 delivery (46 and 21%) and leg O2 delivery (47 and 26%) during Bike and Knee, respectively, almost matching the corresponding reduction in . Altitude acclimatization restored fully peak systemic and leg O2 delivery in CH (2.69 ± 0.27 and 1.28 ± 0.11 l min,1, respectively) to sea level values (2.65 ± 0.15 and 1.16 ± 0.11 l min,1, respectively) during Knee, but not during Bike. During Knee in CH, leg oxygen delivery was similar to normoxia and, therefore, also in spite of a of 55 mmHg. Reducing the size of the active muscle mass improves pulmonary gas exchange during hypoxic exercise, attenuates the Bohr effect on oxygen uploading at the lungs and preserves sea level convective O2 transport to the active muscles. Thus, the altitude-acclimatized human has potentially a similar exercising capacity as at sea level when the exercise model allows for an adequate oxygen delivery (blood flow ×), with only a minor role of per se, when is more than 55 mmHg. [source] Benchmarking epidemiological characteristics of cervical cancer in advance of change in screening practice and commencement of vaccinationAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2007Colin Luke Abstract Objectives: To investigate trends in cervical cancer incidence, mortality and survival by histology for benchmarking purposes ahead of practice change and the introduction of Human Papilloma Virus (HPV) vaccine. Methods: Using data from the South Australian Cancer Registry, age-standardised rates are presented for four-year periods from 1977 to 2004. Socio-demographic and secular predictors of glandular as opposed to squamous cancers are investigated, using multivariable logistic regression. Disease-specific survivals are analysed using Kaplan-Meier product-limit estimates and Cox proportional hazards regression. Results: Incidence and mortality rates reduced by 55.1% and 59.3% respectively between 1977,80 and 2001,04, with larger reductions for squamous than glandular cancers. The ratio of squamous to glandular cancer incidence reduced from 5.4:1 in 1977,88 to 2.8:1 in 1993,2004, with a corresponding reduction from 5.2:1 to 3.0:1 for mortality. Compared with squamous cancers, glandular lesions were more common in patients from higher socio-economic areas, but less common in those over 70 years of age, Aboriginal patients, and those born in Southern Europe. Conclusion: The proportion of cancers comprising glandular lesions has increased, possibly reflecting prevention of squamous cancers through treatment of screen-detected preinvasive lesions. Additional mortality reductions from screening may be limited where the proportion of glandular lesions is high, with vaccination offering the best prospects for gains in the long term. Priority should be given to Aboriginal and Torres Strait Islander women in vaccination programs in view of their high death rate from cervical cancer. [source] Crystallization and preliminary X-ray analysis of substrate complexes of leucine dehydrogenase from Thermoactinomyces intermediusACTA CRYSTALLOGRAPHICA SECTION D, Issue 6-2 2002Tatyana A. Muranova Leucine dehydrogenase is an octameric enzyme which belongs to the superfamily of amino-acid dehydrogenases and catalyses the reversible oxidative deamination of leucine to 2-ketoisocaproate, with the corresponding reduction of the cofactor NAD+. Catalysis by this enzyme is thought to involve a large-scale motion of the enzyme's two domains between an `open' and `closed' form, with the latter representing a conformation of the enzyme in which the partners involved in the hydride-transfer reaction are appropriately positioned for catalysis. Whilst a structure for the open form of the enzyme has been determined, the nature of the closed form has yet to be observed. In order to trap a closed form, crystals of the complexes of leucine dehydrogenase from Thermoactinomyces intermedius with 2-ketoisocaproate and with 2-ketoisocaproate and NAD+ have been obtained by the hanging-drop vapour-diffusion method using PEG 4000 as a precipitant. The crystals of the binary complex with 2-ketoisocaproate belong to space group P212121, with approximate unit-cell parameters a = 106, b = 118, c = 320,Å and an octamer in the asymmetric unit, corresponding to a VM of 3.1,Å3,Da,1. The crystals of the non-productive ternary complex belong to space group P61 or P65, with approximate unit-cell parameters a = b = 117, c = 502,Å and an octamer in the asymmetric unit, corresponding to a VM of 3.0,Å3,Da,1. These crystals diffract X-rays on a synchrotron-radiation source to at least 2.8 and 3.3,Å resolution, respectively, and are suitable for a full structure determination. [source] 19 Cytosolic phospholipase A2 increases proliferation, inhibits apoptosis and facilitates angiogenesis in prostate cancer: a potential new therapeutic targetBJU INTERNATIONAL, Issue 2006M.I. PATEL The end-products from the arachadonic acid (AA) pathway have been shown to be tumourigenic in prostate cancer (CaP). Cytosolic phospholipase A2 (cPLA2) is the enzyme that liberates AA from plasma membranes and feeds it to the cycloxygenase and lipoxygenase pathways. In this study we aim to determine the importance of cPLA2 in prostate cancer by examining human prostate cancer specimens and in vitro cell line models. Immunohistochemistry of human prostate specimens revealed that activated cPLA2 levels were significantly higher in prostate cancer compared to benign glands.. Next to determine if inhibition of cPLA2 would lead to decreases in prostate cancer growth, we treated three CaPcell lines (PC3, DU145 and LNCaP) with pyrrolidine 2 (P2), a specific cPLA2 inhibitor and showed it significantly inhibited the growth of all three cell lines at concentrations between 1,10,M by MTS assay. P2 treatment induced a cell cycle block at G0/G1 and a corresponding reduction in BrdU incoprporation by flow cytometry and 3H-Thymidine incorporation. In addition cPLA2 knock by siRNA also showed a similar inhibition in proliferation, confirming the importance of cPLA2 in CaP proliferation. P2 also induced apoptosis in CaP cell lines by Caspase 3/7 assay. Treatment of Endothelial cell (HUVECs) cells with P2 had a very significant inhibitory effect on capillary tube formation in matrigel. We conclude that cytosolic phospholipase A2 is overactive in human prostate cancer. It leads to CaP proliferation as well as apoptosis. cPLA2 also is required in endothelial angiogenesis. Inhitibion of cPLA2 by P2 will reduce cancer growth, induce apoptosis and inhibit angiogeneisis in an in vitro model. Together, these findings suggest that cPLA2 could be a potential target in CaP treatment and warrants further validation in animal and human trials. [source] The effect of transient balloon occlusion of the mitral valve on left atrial appendage blood flow velocity and spontaneous echo contrastCLINICAL CARDIOLOGY, Issue 7 2000Jianan Wang M.D. Abstract Background: Spontaneous echo contrast (SEC) is a phenomenon that is commonly seen in areas of blood stasis. It is a slowly moving, cloud-like swirling pattern of "smoke" or increased echogenicity recorded on echocardiography. SEC is commonly seen in the left atrium of patients with mitral stenosis or atrial fibrillation. The prescence of SEC has been shown to be a marker of increased thromboembolic risk. Hypothesis: By using transesophageal echocardiography during percutaneous balloon mitral valvotomy (PBMV), the study investigated the relationship between SEC and varying left atrial appendage (LAA) blood flow velocity in the human heart. Methods: Thirty,five patients with rheumatic mitral stenosis underwent percutaneous balloon mitral valvotomy with intraoperative transesophageal echocardiography monitoring. We alternatively measured LAA velocities and observed the left atrium for various grades of SEC (0 = none to 4 = severe) before and after each balloon inflation. Results: Left atrial appendage maximal ejection velocity was reduced from 35 ± 14 to 6 ± 2 mm/s at peak balloon inflation and increased to 40 ± 16 mm/s after balloon deflation. In comparison with the values before balloon inflation and after balloon deflation, LAA velocities were significantly lower (p < 0.001). New or increased SEC grade was observed during 54 of 61 (88%) inflations and unchanged in 7 (12%) inflations at peak balloon inflation. Spontaneous echo contrast became lower in grade after 55 balloon deflations (90%), completely disappeared after 18 deflations (30%), and remained unchanged after 6 deflations (10%). The mean time to achieve maximal SEC grade (2.5 ± 1.2 s) coincided with the mean time to trough LAA velocities (2.3 ±1.1 s) after balloon inflation. Upon deflation, the mean time to lowest SEC grade (2.9 ± 1.8 s) coincided with mean time to achieve maximal LAA velocities (2.7 ± 1.6s). Conclusion: During balloon inflation, the severity of SEC was enhanced with corresponding reduction in LAA flow velocity. Upon balloon deflation, SEC lightens or disappears with increase in LAA flow velocity. [source] Effect of an essential oilcontaining antiseptic mouthrinse on plaque and salivary Streptococcus mutans levelsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2000D. H. Fine Abstract Background: Clinical studies in which antimicrobial mouthrinses were shown to have significant antiplaque activity most frequently have used gingivitis as the clinically relevant endpoint. However, there is evidence to suggest that mouthrinses containing active agents effective against Streptococcus mutans, such as chlorhexidine, may also have a rôle in inhibiting dental caries. This clinical study was conducted to determine the effect of 2×-daily rinsing with an essential oilcontaining antiseptic mouthrinse (Listerine® Antiseptic) on levels of recoverable S. mutans and total streptococci in supragingival interproximal plaque and in saliva. Additionally, a follow-up in vitro study is reported which determined whether a differential susceptibility to the antiseptic mouthrinse exists among different strains of streptococci. Method: Following baseline saliva and plaque sampling for quantification of recoverable S. mutans and total streptococci, 29 qualifying subjects were randomly assigned either the essential oil mouthrinse or a sterile water control. They rinsed with 20 ml for 30 s 2×daily for 11 days and once on the 12th day, in addition to their usual oral hygiene procedures. On day 12, saliva and plaque samples were again collected and microbiological quantification performed. The procedures were repeated with the alternate rinse after a 1-week washout period. Results: The essential oil mouthrinse produced respective reductions of 69.9% and 75.4% in total recoverable streptococci and in S. mutans in plaque, and corresponding reductions of 50.8% and 39.2% in saliva. The in vitro study revealed that streptococci from the mutans group were more susceptible to the bactericidal activity of the essential oil mouthrinse than streptococci from the mitis group. Conclusions: As antimicrobial mouthrinses are most frequently recommended to patients whose mechanical oral hygiene procedures are not adequate for the control of supragingival plaque and gingivitis, this study provides an additional rationale for the inclusion of the essential-oil mouthrinse as an adjunct to daily oral hygiene procedures. [source] EFFECTS OF DAM IMPOUNDMENT ON THE FLOOD REGIME OF NATURAL FLOODPLAIN COMMUNITIES IN THE UPPER CONNECTICUT RIVER,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2002Keith H. Nislow ABSTRACT: Understanding the effects of dams on the inundation regime of natural floodplain communities is critical for effective decision making on dam management or dam removal. To test the implications of hydrologic alteration by dams for floodplain natural communities, we conducted a combined field and modeling study along two reaches in the Connecticut River Rapids Macrosite (CRRM), one of the last remaining flowing water sections of the Upper Connecticut River. We surveyed multiple channel cross sections at both locations and concurrently identified and surveyed the elevations of important natural communities, native species of concern, and nonnative invasive species. Using a hydrologic model, HEC-RAS, we routed estimated pre-and post-impoundment discharges of different design recurrence intervals (two year through 100 year floods) through each reach to establish corresponding reductions in elevation and effective wetted perimeter following post-dam discharge reductions. By comparing (1) the frequency and duration of flooding of these surfaces before and after impoundment and (2) the total area flooded at different recurrence intervals, our goal was to derive a spatially explicit assessment of hydrologic alteration, directly relevant to natural floodplain communities. Post-impoundment hydrologic alteration profoundly affected the subsequent inundation regime, and this impact was particularly true of higher floodplain terraces. These riparian communities, which were flooded, on average, every 20 to 100 years pre-impoundment, were predicted to flood at 100 , 100 year intervals, essentially isolating them completely from riverine influence. At the pre-dam five to ten year floodplain elevations, we observed smaller differences in predicted flood frequency but substantial differences in the total area flooded and in the average flood duration. For floodplain forests in the Upper Connecticut River, this alteration by impoundment suggests that even if other stresses facing these communities (human development, invasive exotics) were alleviated, this may not be sufficient to restore intact natural communities. More generally, our approach provides a way to combine site specific variables with long term gage records in assessing the restorative potential of dam removal. [source] Potential savings from increased use of generic drugs in the elderly: what the experience of Medicaid and other insurance programs means for a Medicare drug benefitPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 4 2004Michael A. Fischer MD Abstract Background Generic medications provide the same clinical effect at lower cost than brand name drugs but little is known about the extent to which such savings are achieved in drug benefit programs serving the elderly. Methods Using patient-level claims data for participants aged 65 or more in one state Medicaid program and in a non-Medicaid drug insurance program for the elderly, we compared the expenditures in each program for brand name prescriptions with the amount that would have been paid for generic versions of the same agents. We then estimated potential savings from increased use of substitutable brand name drugs. Results There was an unrealized annual savings of $3.4 million (3.6% of total drug expenditure) in the Medicaid program studied and $13.7 million (9.5% of total drug expenditure) in the non-Medicaid drug insurance program for the elderly, with corresponding reductions in mean annual per-patient drug costs. Conclusions More widespread use of generic medications represents an important source of unrealized savings in drug coverage programs for the elderly. The Medicaid program limits the excess spending on brand name drugs by imposing pricing restrictions, but many non-Medicaid programs could realize even larger savings from reducing the use of brand name drugs when identical generic products are available. These findings offer some insight into the potential expense of a Medicare prescription drug benefit. Copyright © 2003 John Wiley & Sons, Ltd. [source] The effect of intracellular acidification on the relationship between cell volume and membrane potential in amphibian skeletal muscleTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005James A. Fraser The relationship between cell volume (Vc) and membrane potential (Em) in Rana temporaria striated muscle fibres was investigated under different conditions of intracellular acidification. Confocal microscope xz -scanning monitored the changes in Vc, whilst conventional KCl and pH-sensitive microelectrodes measured Em and intracellular pH (pHi), respectively. Applications of Ringer solutions with added NH4Cl induced rapid reductions in Vc that rapidly reversed upon their withdrawal. These could be directly attributed to the related alterations in extracellular tonicity. However: (1) a slower and persistent decrease in Vc followed the NH4Cl withdrawal, leaving Vc up to 10% below its resting value; (2) similar sustained decreases in resting Vc were produced by the addition and subsequent withdrawal of extracellular solutions in which NaCl was isosmotically replaced with NH4Cl; (3) the same manoeuvres also produced a marked intracellular acidification, that depended upon the duration of the preceding exposure to NH4Cl, of up to 0.53 ± 0.10 pH units; and (4) the corresponding reductions in Vc similarly increased with this exposure time. These reductions in Vc persisted and became more rapid with Cl, deprivation, thus excluding mechanisms involving either direct or indirect actions of pHi upon Cl, -dependent membrane transport. However they were abolished by the Na+,K+ -ATPase inhibitor ouabain. The Em changes that accompanied the addition and withdrawal of NH4+ conformed to a Nernst equation modified to include realistic NH4+ permeability terms, and thus the withdrawal of NH4+ restored Em to close to control values despite a persistent change in Vc. Finally these Em changes persisted and assumed faster kinetics with Cl, deprivation. The relative changes in Vc, Em and pHi were compared to predictions from the recent model of Fraser and Huang published in 2004 that related steady-state values of Vc and Em to the mean charge valency (zx) of intracellular membrane-impermeant anions, X,i. By assuming accepted values of intracellular buffering capacity (,i), intracellular acidification was shown to produce quantitatively predictable decreases in Vc. These findings thus provide experimental evidence that titration of the anionic zx by increased intracellular [H+] causes cellular volume decrease in the presence of normal Na+,K+ - ATPase activity, with Cl, -dependent membrane fluxes only influencing the kinetics of such changes. [source] | |||||||||||||