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This paper presents a system of sensors used in flash flood prediction that offers critical real-time information used to provide early warnings that can provide the minutes needed for persons to evacuate before imminent events. Flooding is one of the most serious natural disasters humans confront in terms of loss of life and results in long-term effects, which often have severely adverse social consequences. However, flash floods are potentially more dangerous to life because there is often little or no forewarning of the impending disaster. The Emergency Water Information Network (EWIN) offers a solution that integrates an early warning system, notifications, and real-time monitoring of flash flood risks. The platform has been implemented in Colima, Mexico covering the Colima and Villa de Alvarez metropolitan area. This platform consists of eight fixed riverside hydrological monitoring stations, eight meteorological stations, nomadic mobile monitoring stations called "drifters" used in the flow, and a sniffer with data muling capability. The results show that this platform effectively compiles and forwards information to decision-makers, government officials, and the general public, potentially providing valuable minutes for people to evacuate dangerous areas.

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Continuous peripheral nerve blockade is a common technique in the analgesic management for many procedures. Leakage of local anaesthetic from around the nerve catheter insertion site can increase the chance of catheter dislodgement, risks infective complications, and could divert anaesthetic away from the nerve causing the block to fail. We conducted a randomised controlled trial to assess whether the type of nerve catheter influenced local anaesthetic leak rate. One hundred and ten patients scheduled for elective unilateral total knee arthroplasty were randomised to receive a perineural catheter with either a catheter over needle (CON) system (Pajunk® E-Cath) (PAJUNK® GmbH, Medizintechnologie, Geisingen, Germany), or catheter through needle (CTN) system (Pajunk® SonoLong) (PAJUNK® GmbH, Medizintechnologie, Geisingen, Germany). There was no statistically significant difference in the rate of leaking catheters between groups (CON 1.8% versus CTN 3.7%; P=0.618), however, the overall leak rate was much lower than anticipated from pilot data. The CON system was on average faster to insert (CON 357 seconds versus CTN 482 seconds; P=0.004), but associated with poorer needle visibility under ultrasound (Likert scale 1-5, mean [SD], CON 3.31 [0.96] versus CTN 3.89 [0.84]; P=0.001). All seven instances of inadvertent catheter dislodgement occurred in the CTN group (P=0.006). There was no statistically significant difference between groups in the proportion of patients who had adequate analgesia on day one (CON 80% versus CTN 86.5%; P=0.294) and day two postoperatively (CON 85.5% versus CTN 91.8%; P=0.369). Our findings show the overall leak rate to be very low with both catheter systems; however, the CON system may have advantages in terms of speed of use and rate of inadvertent catheter dislodgement.

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CONTEXT: Routine point-of-care (POC) glucose monitoring in the pediatric setting has become increasingly important, both for assessing hypoglycemia as well as hyperglycemia. A reliable and precise system is required to monitor pediatric patients. OBJECTIVES: The aim of this study was to evaluate the Nova Biomedical StatStrip POC glucometer against the Roche ACCU-CHEK Inform in lieu of our currently used LifeScanSureStepFlexx POC glucose analyzer. DESIGN AND METHODS: Intra-assay and inter-assay precision, linearity, correlation and interference studies were performed as per the NCCLS criteria. An analysis of 37 pediatric samples across the linearity ranges of all the meters was used to assess concordance between the systems. RESULTS: The Nova StatStrip glucometer demonstrated an excellent coefficient of variation (<5%) for glucose across the entire analytical measurement range. The Nova StatStrip also had good concordance with the central laboratory (Bland-Altman plots r(2)=0.01), while Roche Inform had poorer correlation (Bland-Altman plots r(2)=0.46). We also evaluated the effect of hematocrit (20-60%) and maltose (100-500mg/dL) on the Nova StatStrip analyzer and demonstrated that there is little to no interference by either. CONCLUSIONS: The Nova StatStrip system gave the best performance with acceptable imprecision, good correlation, and minimal to no interference from hematocrit levels or maltose. The Nova StatStrip is a satisfactory replacement for our POC glucometer system and, additionally, provides results in less time (just 6 s) utilizing a lower amount of blood with the advantage of being immediately interfaced to our laboratory information systems.

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The aim of this study was to investigate the association between foot type and the morphometry of selected muscles and tendons of the lower limb. Sixty-one healthy participants (31 male, 30 female; aged 27.1 ± 8.8 years) underwent gray-scale musculoskeletal ultrasound examination to determine the anterior-posterior (AP) thickness of tibialis anterior, tibialis posterior, and peroneus longus muscles and tendons as well as the Achilles tendon. Foot type was classified based on arch height and footprint measurements. Potentially confounding variables (height, weight, hip and waist circumference, rearfoot and ankle joint range of motion, and levels of physical activity) were also measured. Multiple linear regression models were used to determine the association between foot type with muscle and tendon morphometry accounting for potentially confounding variables. Foot type was significantly and independently associated with AP thickness of the tibialis anterior tendon, peroneus longus muscle, and Achilles tendon, accounting for approximately 7% to 16% of the variation. Flat-arched feet were associated with a thicker tibialis anterior tendon, a thicker peroneus longus muscle, and a thinner Achilles tendon. Foot type is associated with morphometry of tendons that control sagittal plane motion of the rearfoot; and the peroneus longus muscle that controls frontal plane motion of the rearfoot. These findings may be related to differences in tendon loading during gait.

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BACKGROUND AND PURPOSE: Cyclooxygenase inhibitors function to reduce levels of prostaglandin E(2) (PGE(2)) and are broadly efficacious in models of bladder overactivity. We therefore investigated a regulation of urinary bladder function in conscious rats by modulation of the EP(3) receptor for PGE(2). EXPERIMENTAL APPROACH: The activity of the EP(3) receptor agonist GR63799X, and EP(3) receptor antagonists, CM9 and DG041, at recombinant EP(3) receptors was evaluated in vitro. In vivo, intraduodenal dosing during conscious, continuous-filling cystometry of spontaneously hypertensive rats was utilized to determine the urodynamic effect of EP(3) receptor modulation. KEY RESULTS: GR63799X dose-dependently (0.001-1 mg x kg(-1)) reduced bladder capacity, as indicated by a reduction in both the micturition interval and volume of urine per void. In contrast, CM9 (10 and 30 mg x kg(-1)) and DG041 (30 mg x kg(-1)) enhanced bladder capacity, as indicated by significantly longer micturition intervals and larger void volumes. CM9 and DG041 inhibited the responses to GR63799X supporting the in vivo activity of these pharmacological agents at the EP(3) receptor. In addition to its effect on bladder capacity, GR63799X increased endogenous urine production. Intra-arterial infusion of saline mimicked the enhancement of urine flow observed with GR63799X, and the response was inhibited by CM9. CONCLUSIONS AND IMPLICATIONS: These data support the EP(3) receptor as a modulator of urinary bladder activity in the conscious rat, and in addition, indicate a role for EP(3) receptor activity in regulating urine flow.

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This paper presents simulated and measured phantom results for the possible effects that head worn jewellery may have on the relative levels of energy absorbed in the human head with cellular enabled mobile communication devices. The FDTD electromagnetic code used with simple and complex anatomical mathematical phantoms was used to consider the interactions of metallic jewellery, heads and representative sources at 900 and 1800 MHz. Illuminated metallic pins of different lengths were positioned in front of the face. Initially, a homogenous phantom was used to understand the relative enhancement mechanisms. This geometry allowed the results to be validated with the industry standard DASY4 robot SAR measurement system related to the CENELEC head. Jewellery pins were then added to an anatomically realistic head. The relative increase in the 1 g and 10 g SAR, due to a pin with a length 0.4lambda near the eyebrows of a complex, anatomically realistic head was approximately three times at 1800 MHz. Such pins increased the SAR averaged over a 1 g or 10 g mass by redistributing the energy absorbed inside the head and focusing this energy towards the area of the head nearest to the centre of the pin. Although, the pins increased the SAR, the SAR standards were not breached and the jewellery produced lower values than those of previous studies when the source was positioned close to the ear.

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BACKGROUND: Although "aspirin resistance" (AR-inadequate platelet inhibition as suggested by in vitro testing of aspirin-treated patients) has been widely studied in adults and linked to increased risk of adverse outcomes, its prevalence and clinical significance are largely unknown in children. PROCEDURE: To determine AR prevalence in children and its relationship to assay methodology, we undertook a cross-sectional study of 44 children (1-17 years, 24 male) on aspirin for various indications and considered three published definitions of AR in adults: platelet aggregation >/=70% to 10 microM adenosine diphosphate and >/=20% to 0.5 mg/ml arachidonic acid (AA), normal PFA-100(R) closure time and elevated urinary 11-dehydro thromboxane B(2) (11dhTxB(2)) concentration. RESULTS: Six subjects exhibited AR according to at least one of the criteria (5 by PFA-100(R), 1 by aggregometry and 11dhTxB(2) criteria); nearly all subjects had low levels of 11dhTxB(2) compared with controls. Subjects studied prior to therapy showed pronounced changes in AR parameters after aspirin dosing (e.g., mean aggregation to AA decreased from 82% to 6%, P < 0.001), confirming an aspirin effect. Subjects with AR did not differ from aspirin responsive subjects in terms of age, race, platelet count, or aspirin dose, indication or therapy duration. There was minimal correlation between assays. CONCLUSIONS: In this initial prevalence study of a clinically diverse group of pediatric patients, frequencies of AR were assay-dependent; however, the prevalence of true AR is likely low in children (2.3%; 95% CI 0.1-10.7%), in agreement with adult studies. To better define the clinical relevance of AR in children, multicenter, prospective cohort studies are imperative.

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We compared the effects of dopamine and norepinephrine on vasopressin (AVP)-stimulated increases in osmotic water permeability (Pf) and cAMP accumulation in the rat inner medullary collecting duct (IMCD). Both dopamine and norepinephrine inhibited AVP-induced Pf and cAMP accumulation in a concentration-dependent manner; however, norepinephrine was approximately 100-fold more potent than dopamine. The effects of dopamine on Pf were antagonized by the selective alpha(2)-adrenoceptor antagonist, rauwolscine (10 nM--1 microM). Clozapine (10 microM), a dopamine D(4) receptor antagonist with significant activity at adrenergic receptors, partially attenuated both dopamine and norepinephrine-induced decreases in AVP-stimulated Pf. Dopamine-induced inhibition of AVP-dependent cAMP levels was antagonized by the alpha(2)-adrenoceptor antagonists, rauwolscine, idazoxan, and yohimbine, but not by the dopamine receptor antagonists, spiperone, SCH-23390, or raclopride. Clozapine (1--10 microM) inhibited the effects of both dopamine and norepinephrine on AVP-stimulated cAMP levels. We conclude that the inhibitory effects of dopamine on AVP-induced Pf and cAMP accumulation in the rat IMCD are mediated via alpha(2)-adrenoceptors.

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Exposure of pregnant rats to the solvent 2-methoxyethanol (2ME) and radiofrequency (RF) radiation results in greater than additive fetal malformations (Nelson, B.K., Conover, D.L., Brightwell, W.S., Shaw, P.B., Werren, D.W., Edwards, R.M., Lary, J.M., 1991. Marked increase in the teratogenicity of the combined administration of the industrial solvent 2-methoxyethanol and radiofrequency radiation in rats. Teratology 43, 621-34; Nelson, B.K., Conover, D.L., Shaw, P.B., Werren, D.W., Edwards, R.M., Hoberman, A.M., 1994. Interactive developmental toxicity of radiofrequency radiation and 2-methoxyethanol in rats. Teratology 50, 275-93). The current study evaluated the metabolism of 14C-labeled 2ME and the distribution of methoxyacetic acid (MAA) in maternal and embryonic tissues of pregnant Sprague-Dawley rats either exposed to 10 MHz RF radiation or sham conditions. Additionally, adduct formation for both plasma and embryonic protein was tested as a possible biomarker for the observed 2ME/RF teratogenicity. Rats were administered [ethanol-1,2-(14)C]-2ME (150 mg/kg, 161 microCi/rat average) by gavage on gestation day 13 immediately before RF radiation sufficient to elevate body temperature to 42 degrees C for 30 min. Concurrent sham- and RF-exposed rats were sacrificed at 3, 6, 24 or 48 h for harvest of maternal blood, urine, embryos and extra-embryonic fluid. Tissues were either digested for determination of radioactivity or deproteinized with TCA and analyzed by HPLC for quantification of 2ME metabolites. Results show the presence of 2ME and seven metabolites, with the major metabolite, MAA, peaking at 6 h in the tissues tested. MAA, the proximal teratogen, was detectable in maternal serum, urine, embryo and extraembryonic fluid 48 h after dosing. Clearance of total body 14C was significantly reduced for the RF-exposed animals (P<0.05) for the 24-48 h period, but MAA values for serum, embryos and extraembryonic fluid were similar for both sham- and RF-exposed rats. Additionally, no difference was noted for 2ME metabolite profiles in urine or tissue for sham- or RF-exposed rats, thus eliminating an effect of RF radiation on MAA production as a possible explanation for the reported RF-2ME synergism. Subsequently, serum and embryo protein-bound adducts were evaluated by analysis of covalently bound radioactivity. Serum protein binding was significantly higher for sham than RF rats at 3- and 6-h - highest for sham rats at 6 h (519+/-95 microg as parent 2ME/g of protein) whereas RF serum values were highest at 24 h (266+/-79 microg/g protein). Embryonic protein binding was significantly higher for sham rats at 6 h, but binding was highest for both groups at 24 h (sham=229+/-71 microg/g, RF=185+/-48 microg/g). Formation of protein adducts after 2ME is thought to be related to levels of methoxyacetaldehyde, a reactive intermediate in the formation of MAA. These results suggest that no direct relationship exists for covalent binding in the embryo which would explain RF-2ME synergistic malformations. In comparison with urinary metabolites, the relatively slow elimination of adducted serum 2ME indicates that analysis of protein-bound concentrations could be a potential tool for long- term biomonitoring of worker exposure.

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Although secondary hyperparathyroidism is a common complication of chronic renal failure, few studies have examined the characteristics of parathyroid hormone (PTH) binding to the kidney or the regulation of the PTH receptor in chronic renal disease. In this study we measured PTH binding to the PTH-1 receptor in renal cortical membranes from normal rats and from rats with experimentally induced chronic renal failure. In normal rats, analysis of saturation binding experiments using 125I PTH-related peptide (chicken, cPTHrP) revealed apparent Kd and Bmax values of 1.16 +/- 0.14 nmol/l and 338 +/- 22.7 fmol/mg, respectively. Three weeks following induction of renal failure there was no change in the affinity of the PTH-1 receptor (Kd = 1.51 +/- 0.24 nmol/l) but the Bmax was reduced by 45% (183 +/- 32.5). In normal rats which had undergone thyroparathyroidectomy, the Kd was unchanged (1.17 +/- 0.09) while the Bmax increased to 459 +/- 31 fmol/mg. We conclude that chronic renal failure is accompanied by a downregulation of renal PTH-1 receptors.

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Approximately 9,000,000 US workers are occupationally exposed to radiofrequency (RF) radiation; over 250,000 operate RF dielectric heaters. Our purpose was to determine whether male RF heater operators experience increased adverse reproductive effects reflected in reduced semen quality or altered hormone levels. We measured incident RF heater radiation exposures and RF-induced foot currents at four companies. For 12 male heater operators and a comparison group of 34 RF-unexposed men, we measured 33 parameters of semen quality and four serum hormones. Despite wide variation in individual exposure levels, near field strengths and induced foot currents did not exceed current standard levels and guidelines. We observed minor semen quality and hormonal differences between the groups, including a slightly higher mean follicle-stimulating hormone level for exposed operators (7.6 vs 5.8 mIU/mL). Further occupational studies of RF-exposed men may be warranted.

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Although there have been a number of studies indicating a heritable component for osteoporosis in middle to late adulthood, the etiology of osteoporosis in young people is uncertain. The present study aims to evaluate the extent to which genetic factors influence familial resemblance for bone mineral density (BMD) in families ascertained on the basis of young osteoporotic probands. The sample comprises eight families (74 total individuals) that were identified through a proband under the age of 35 years with a history of two or more fractures and a spinal bone density of at least 2.5 SDs below the mean for age and sex (Z score). Secondary causes of osteoporosis were excluded in the probands. In total, 27% (18/66) of the probands' relatives had osteoporosis and an additional 30% (20/66) had osteopenia. Classical segregation analysis was performed to evaluate the extent to which a genetic etiology could account for familial resemblance in these families. The results indicate a major gene of codominant inheritance for spinal BMD. Model-fitting comparisons revealed no support for environmental effects or for polygenic inheritance.

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The transport of the angiotensin II receptor antagonist losartan and its interaction with organic anion transport were examined in the isolated perfused rabbit proximal tubule. Losartan reversibly inhibited the secretion of para-aminohippurate (PAH) in a concentration-dependent manner (IC50 = 15 +/- 0.5 microM). Other angiotensin II receptor antagonists also inhibited PAH secretion with similar potencies: eprosartan, 11 +/- 2.3 microM; irbesartan, 17 +/- 2.2 microM; and valsartan 3 +/- 0.6 microM. [3H]Losartan was secreted by the proximal tubule by a saturable and probenecid-sensitive mechanism. The affinity of losartan for the organic anion transporter (Km = 12.3 +/-1.8 microM) was significantly greater than that of PAH (Km = 88.5 +/- 10.7 microM). [3H]Losartan secretion was stimulated in the presence of alpha-ketoglutarate, suggesting that losartan, like PAH, enters the cell in exchange for a dicarboxylate. These results demonstrate that losartan and probably other nonpeptide angiotensin II receptor antagonists are secreted by an organic anion transporter that is similar to, if not identical with, the classic PAH transporter.

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The genus Cynodon (Gramineae), comprised of 9 species, is geographically widely distributed and genetically diverse. Information on the amounts of molecular genetic variation among and within Cynodon taxa is needed to enhance understanding of phylogenetic relations and facilitate germplasm management and breeding improvement efforts. Genetic relatedness among 62 Cynodon accessions, representing eight species, was assessed using DNA amplification fingerprinting (DAF). Ten 8-mer oligonucleotides were used to amplify specific Cynodon genomic sequences. The DNA amplification products of individual accessions were scored for presence (1) or absence (0) of bands. Similarity matrices were developed and the accessions were grouped by cluster (UPGMA) and principal coordinate analysis. Analyses were conducted within ploidy level (2x = 18 and 4x = 36) and over ploidy levels. Each primer revealed polymorphic loci among accessions within species. Of 539 loci (bands) scored, 496 (92%) were polymorphic. Cynodon arcuatus was clearly separated from other species by numerous monomorphic bands. The strongest species similarities were between C. aethiopicus and C. arcuatus, C. transvaalensis and C. plectostachyus, and C. incompletus and C. nlemfuensis. Intraspecific variation was least for C. aethiopicus, C. arcuatus, and C. transvaalensis, and greatest for C. dactylon. Accessions of like taxonomic classification were generally clustered, except the cosmopolitan C. dactylon var. dactylon and C. dactylon var. afganicus. Within taxa, accessions differing in chromosome number clustered in all instances indicating the 2x and 4x forms to be closely related. Little, if any, relationship was found between relatedness as indicated by the DAF profiles and previous estimates of hybridization potential between the different taxa.

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Neutral endopeptidase (NEP) activity was measured in various nephron segments dissected from rat and rabbit kidney. In the rat, only the proximal straight tubule and glomerulus had measurable NEP activity of 86 +/- 11.3 pmol/min/mm tubule length and 5.8 +/- 1.5 pmol/min/glomerulus, respectively. In the rabbit, significant activity was observed in both the proximal convoluted tubule (70.8 +/- 7.2 pmol/min/mm) and proximal straight tubule (29.6 +/- 2.3 pmol/min/mm) as well as in the glomerulus (12.8 +/- 2.2 pmol/min/glomerulus). In the rat proximal tubule, phosphoramidon and thiorphan inhibited NEP activity, with IC50 values of 26.6 +/- 6.0 and 6.9 +/- 1.6 nmol/l, respectively. Incubation of rat proximal tubules with phorbol 12-myristate 13-acetate resulted in a 50% reduction in membrane-associated NEP activity. The results demonstrate that in both the rat and rabbit NEP is restricted to the glomerulus and proximal tubule. This localized distribution of NEP and its potential regulation by the protein kinase C pathway may play a key role in determining local concentrations of important regulatory peptides in the kidney.

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Human CC chemokines macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, and RANTES (regulated on activation normal T cell expressed) self-associate to form high-molecular mass aggregates. To explore the biological significance of chemokine aggregation, nonaggregating variants were sought. The phenotypes of 105 hMIP-1alpha variants generated by systematic mutagenesis and expression in yeast were determined. hMIP-1alpha residues Asp26 and Glu66 were critical to the self-association process. Substitution at either residue resulted in the formation of essentially homogenous tetramers at 0.5 mg/ml. Substitution of identical or analogous residues in homologous positions in both hMIP-1beta and RANTES demonstrated that they were also critical to aggregation. Our analysis suggests that a single charged residue at either position 26 or 66 is insufficient to support extensive aggregation and that two charged residues must be present. Solution of the three-dimensional NMR structure of hMIP-1alpha has enabled comparison of these residues in hMIP-1beta and RANTES. Aggregated and disaggregated forms of hMIP-1alpha, hMIP-1beta, and RANTES generally have equivalent G-protein-coupled receptor-mediated biological potencies. We have therefore generated novel reagents to evaluate the role of hMIP-1alpha, hMIP-1beta, and RANTES aggregation in vitro and in vivo. The disaggregated chemokines retained their human immunodeficiency virus (HIV) inhibitory activities. Surprisingly, high concentrations of RANTES, but not disaggregated RANTES variants, enhanced infection of cells by both M- and T-tropic HIV isolates/strains. This observation has important implications for potential therapeutic uses of chemokines implying that disaggregated forms may be necessary for safe clinical investigation.

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A cDNA clone with 53% amino acid identity to the human type II sodium-dependent phosphate transporter (NaPi-3) was isolated from human small intestine and lung. Functional characterization in Xenopus laevis oocytes showed this cDNA to encode a sodium-dependent phosphate transporter. The electrogenic response is similar to that found in other type II transporters but an inverse pH dependence was observed. By Northern blot, a 4.2-kb transcript was found to be abundantly expressed in lung and, to a lesser degree, in several other tissues of epithelial origin including small intestine, pancreas, prostate, and kidney. This transcript encompasses a 2.073-kb open reading frame which is most closely related (78% amino acid identity) to the mouse sodium-dependent phosphate transporter IIb isoform. This novel transporter, designated human NaPi-3b (Genbank AF111856), appears to be an isoform of the mammalian renal type II co-transporter family.

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OBJECTIVE: This research was conducted to determine if altered environmental temperatures would affect the interactive developmental toxicity of radiofrequency (RF) radiation and the industrial solvent, 2-methoxyethanol (2ME). This is important because RF radiation is used in a variety of workplaces that have poorly controlled environmental temperatures, and many workers are concurrently exposed to various chemicals. Furthermore, we have previously demonstrated that combined exposure to RF radiation (10 MHz) and 2ME produces enhanced teratogenicity in rats. METHODS: RF radiation sufficient to maintain colonic temperatures at the control value (38degrees ), 39.0degrees or 40.0 degrees C for 2 or 4 h combined with either 0 or 100 mg/ kg 2ME at environmental temperatures of 18 degrees , 24 degrees and 30 degrees C (65 degrees , 75 degrees , and 85 degrees F) were given on gestation day 13 to Sprague-Dawley rats. Dams were killed on gestation day 20, and the fetuses were examined for external malformations. RESULTS AND CONCLUSIONS: Environmental temperature does affect the specific absorption rate (SAR) necessary to maintain a specific colonic temperature but does not affect the interactive developmental toxicity of RF radiation and 2ME in rats. These results, consistent with the literature, add to the evidence that the developmental toxicity of RF radiation (combined or alone) is associated with colonic temperature, not with SAR.

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Saliva is an enriched milieu containing biologically active proteins, including several different growth factors and cytokines. This study documents that vascular endothelial growth factor (VEGF), a potent, multifunctional, angiogenic cytokine, is a component of normal human saliva. VEGF was measured by ELISA in whole saliva (median concentration, 460 pg/ml) and in ductal secretions obtained from the parotid (277 pg/ml) and the submandibular-sublingual (80 pg/ml) salivary glands. VEGF seems to be synthesized endogenously by the salivary glands because both VEGF mRNA and protein (as revealed by in situ reverse transcriptase-PCR and by immunohistochemistry, respectively) colocalized to serous acinar cells and ductal epithelial cells within the parotid, submandibular, and minor salivary glands. These findings point to the existence of a "salivary VEGF system." It is possible that salivary VEGF plays a role in regulating physiologic and pathologic angiogenic and other vascular responses in salivary and mucosal tissues. And in particular, the presence of VEGF in saliva may contribute to the remarkable healing capacity of the oral mucosa as well as other regions of the digestive tract.

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