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PubMed2002

Thymosin beta 4 promotes corneal wound healing and decreases inflammation in vivo following alkali injury.

Previously, thymosin beta 4 (Tbeta(4)) was found to promote wound healing in full thickness skin wounds and heptanol debrided corneas. Here, the effect of Tbeta(4) was examined treatment on corneal wound healing and inflammation in vivo after alkali injury, a more severe wound of the eye. Corneas from 129 Sv mice were chemically burned with a 2 mm disc soaked in 1 N NaOH for 30 sec. Eyes were irrigated copiously with phosphate buffered saline (PBS) and then treated topically with either Tbeta(4) (5 microg/5 microl PBS) or 5 microl PBS twice daily. Animals were killed, the eyes were enucleated, fixed and embedded in plastic resin or prepared for mRNA analysis. Mouse corneas topically treated with 5 microg of Tbeta(4) twice daily after alkali injury demonstrated accelerated re-epithelialization at all time points and decreased polymorphonuclear leukocyte (PMN) infiltration at 7 days post injury (p.i.) when compared to PBS-treated controls. mRNA transcript levels were decreased several fold for interleukin (IL)-lbeta, and the chemokines macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, MIP-2 and monocyte chemoattractant protein (MCP)-1 from 1 to 7 days after injury in the Tbeta(4)- vs. PBS-treated corneas. Thus, Tbeta(4) may provide a new clinical treatment for severe traumatic corneal wound disorders by promoting rapid corneal wound healing and decreasing both PMN infiltration and inflammatory cytokine and chemokine mRNA levels.

Administration, Topical↗
PubMed1995

Effect of alkali treatments on the nutritive value of common bean (Phaseolus vulgaris).

The effect of alkali treatments of common bean seeds with red seed coat on the stability of antinutritional factors such as tannins, phytates and trypsim inhibitors, vitamins such as niacin and riboflavin and on protein quality has been studied. The samples were processed by soaking and pressure cooking in alkalies such as sodium hydroxide, sodium carbonate and sodium bicarbonate. At low temperature sodium carbonate and at high temperature sodium bicarbonate were found to be most effective in the extraction of tannins. At both low and high temperatures sodium carbonate was found to be more efficient in destruction of phytates. In the case of trypsin inhibitors, extraction at both low and high temperatures with sodium bicarbonate was most effective. Sodium hydroxide treatment was found to be better as far as the retention of niacin and riboflavin was considered.

Alkalies↗
PubMed2003

Effects of alkali metal ions on some virulence traits of Candida albicans.

The effects of the alkali metal ions (Li+, Na+ and K+) on the growth and on certain virulence factors (adhesion, cell-surface hydrophobicity and germinating ability) of Candida albicans were determined. High concentrations of these ions displayed an inhibitory effect on the growth of the Candida cells; preincubation in their presence showed a negative effect on all virulence factors studied. The changes induced during the preincubation remained there even when high concentration of the ions was removed from the cell suspension. In contrast, a considerable growth was found at high Na+ and K+ concentrations. Although alkali metal ions significantly decreased certain virulence traits of the fungus they did not totally inhibit adhesion and germ-tube formation. This suggests that C. albicans may represent a health hazard even at a high salt concentration.

Candida albicans↗
PubMed2006

Structure and bonding of methyl alkali metal molecules.

We have carried out a theoretical investigation of the methyl alkali metals CH3 M with M=Li, Na, K and Rb using density functional theory (DFT) at the BP86/TZ2P level. Our purpose is to determine how the structure and thermochemistry (e.g., C-M bond lengths and strengths) of these organoalkali metal compounds depend on the metal atom, and to understand the emerging trends in terms of quantitative Kohn-Sham molecular orbital (KS-MO) theory. The C-M bond becomes longer and weaker if one goes from Li to the more electropositive Rb. Also, the polarity of the C-M bond increases along this series but it preserves a strong intrinsic preference to homolytic over ionic dissociation in the gas phase. We show that a description of the bonding mechanism in terms of a polar C-M electron-pair bond between the methyl radical and alkali metal atom is just as natural as an ionic description (i.e., in terms of CH3-+M+) and that it provides a straightforward way of understanding all observed trends.

Metals, Alkali↗
PubMed1975

Corneal alkali burns arising from accidental instillation of a hair straightener.

A patient sustained mild bilateral alkali burns of the cornea following ocular exposure to a commercial hair straightening preparation. This compound and three other products all had an alkaline pH which was not reduced to neutrality by the neutralizer provided. Corneal alkali burns similar to those seen in our patient were produced in experimental animals after brief exposure. Histologic changes were primarily limited to the cornea. The warning against ocular exposure printed on the containers or package insert is not sufficiently emphatic to protect the consumer.

Alkalies↗
PubMed1976

Surface ultrastructure in alkali-burned rabbit corneas.

The scanning electron microscope was used to follow morphologic events after alkali burn of rabbit corneas. Immediately after a burn there was extensive destruction and shrinkage of the epithelial cells. In subsequent healing, the regenerated superficial cells were morphologically abnormal and possed multiloculated cysts; three months later the normal polygonal packing of cells was not observed. Although the shape of these cells was irregular, microprojections were present on the cell surface. Basal cells were usually observed at the edge of an epithelial defect, an area where the epithelium was easily detached from the basement membrane. In long-standing epithelial defects, the basement membrane became eroded in a spot-like manner after about two weeks. Eventually, when a frank stromal ulcer had formed, bundles of collagen fibrils were visible in a meshwork-like fashion. These changes did not seem to be caused by the direct action of alkali but rather by latent secondary factors that took days or weeks to activate.

Alkalies↗
PubMed1978

A light microscopic study of ground substance changes in alkali-burned corneas.

Retrocorneal fibrous membranes occurred in 100% of 33 rabbit eyes burned with 4N sodium hydroxide. All membranes exhibited markedly positive colloidal iron/Alcian blue ground substance staining relative to unburned sections of the same corneas and to normal controls. Retrocorneal fibrous membranes also gradually acquired PAS reactivity greater than either unburned sections of the same corneas or uninjured eyes. Colloidal iron/Alcian blue reactivity of retrocorneal fibrous membranes was similar to that which developed in the alkali-induced stromal scars. One histologic section revealed retrocorneal membranogenesis by stromal components that had penetrated a small alkali-induced break in Descemet's membrane.

Alkalies↗
PubMed1990

Influence of alkali metal cations on the transport of calcium by phosphatidate in multi-phase systems.

The effects of alkali metal cations on the rates at which Ca2+ and phosphatidic acid were cotransported from aqueous to hydrocarbon medium were examined. The alkali metal cations remained in the aqueous phase yet specifically influenced the transport of Ca2+ into the hydrocarbon solvent. For the physiological cations, Na+ and K+, there were critical concentration ranges in which small changes in concentration effected sharp changes in transport rates. The maximal rate observed with Na+ was an order of magnitude greater than that with K+; however, unlike Na+, K+ promoted low levels of transport below the critical concentration range. Li+ effected only low levels of transport even at high concentrations, whereas Rb+ and Cs+ induced transport at rates proportional to their concentrations. These results are discussed in terms of a classical ionophore model for the complex composed of a neutral phosphatidic acid dimer bridged by Ca2+.

Biological Transport, Active↗
PubMed1989

Abundant alkali-sensitive sites in DNA of human and mouse sperm.

The DNA of human and mouse sperm cells was analyzed by single-cell microgel electrophoresis, by agarose gel electrophoresis, and by alkaline elution--three techniques that can detect single-strand DNA breaks and/or labile sites. Under these conditions a surprisingly large number of single-strand DNA breaks, approximately 10(6) to 10(7) per genome, were detected in human and mouse sperm but not in human lymphocytes or in mouse bone marrow cells. These breaks were also present in chicken erythrocyte DNA, which is also highly condensed. These breaks were not observed under neutral pH conditions nor under denaturing conditions not involving alkali, suggesting that these sites are alkali-sensitive and do not represent preexisting single-strand breaks. The high frequency of such sites in sperm from healthy mouse and human donors suggests that they represent a functional characteristic of condensed chromatin rather than DNA damage.

Alkalies↗
PubMed1983

Coordinate expression of alkali and DTNB myosin light chains during transformation of rabbit fast muscle by chronic stimulation.

Chronic nerve stimulation induces an almost complete exchange of the fast myosin light chains (LC) LC1f and LC2f to the slow light chains LC1s and LC2s. LC3f decreases only by 30%. The exchange of the DTNB LCs (LC2f to LC2s) precedes that of LC1f to LC1s. However, the equimolar ratio of total alkali to total DTNB LCs is maintained. This points to a hitherto unknown regulation that preserves this ratio independent of whether alkali and DTNB LCs are expressed in fast or slow isotypes.

Alkalies↗
PubMed1991

Chemical burns of the eye with special reference to alkali burns.

Alkali burns of the eye are more severe than acid burns because of the rapid penetration through the cornea and anterior chamber, combining with cell membrane lipids, thereby resulting in disruption of the cells and stromal mucopolysaccharides with concomitant tissue softening. Effective emergency measures must be instituted immediately followed by careful clinical evaluation in order to recognize and treat problems as they arise. We present our experience with 27 patients who sustained corneal lime burns, two of which are discussed in detail. The problem of chemical burns of the eye is reviewed with special emphasis on alkali burns.

Alkalies↗
PubMed1996

Treatment of a severe alkali burn.

The case history of a 20-year-old male patient who sustained an 85 per cent total body surface area alkali burn to his skin, after falling into a caustic lime pit, is reported. Considerable problems regarding the correct estimate of burn wound depth, predominant location of the deepest burn on the posterior half of the body, appropriate wound coverage, and lack of sufficient skin graft donor sites required a complex treatment plan. Excisions to fascia and intradermal debridement were required to achieve an appropriate bed for wound closure. Five per cent mafenide acetate solution (Sulfamylon) was applied to prevent burn wound sepsis. Human allografts and Biobrane were used extensively to achieve temporary wound closure, to provide mechanical protection of freshly autografted wounds, and to prevent desiccation following application of cultured epidermal autografts on to debrided wounds and split thickness skin grafted donor sites. The case illustrates a number of problems associated with the evaluation and treatment of patients suffering severe alkali burns, and demonstrates the implementation of both established and evolving technologies in the management of these injuries.

Adult↗
PubMed2005

Alkali ocular burns in Martinique (French West Indies) Evaluation of the use of an amphoteric solution as the rinsing product.

PRECIS: During the 4 years of this study, we noted 66 cases of alkali ocular burns, or approximately 16 cases per year, nearly half (45.5%) of which are due to an assault. For grade 1 and 2 burns the time elapsed to reepithelialization appears to be shorter when rinsed with Diphoterine* versus physiological solution. PURPOSE: Comparison of the effectiveness of two rinsing solutions for emergency use: a physiological solution and an amphoteric solution (Diphoterine*, Laboratories Prevor, Valmondois, France). Description of the clinical and progressive characteristics of alkali burns treated at the University Hospital Center of Fort de France in Martinique (French West Indies). DESIGN: Prospective consecutive observational case series and nonrandomized comparative study. PARTICIPANTS: Sixty-six patients were included. The total number of burned eyes is 104. Forty-eight eyes (46%) were rinsed with physiological solution and 56 eyes (54%) with Diphoterine*. METHODS: All patients benefited from an ocular rinse with 500ml of physiological solution or Diphoterine*, followed by a complete ophthalmologic exam. The ocular injuries were classified according to the Roper-Hall modification of the Hughes classification system. The same standardized therapeutic protocol was applied and adapted to the seriousness of the burn. MAIN OUTCOME MEASURES: Demographic data, time to corneal reepithelialization, final best corrected visual acuity and complications were analysed. RESULTS: Twenty-eight (42.4%) patients have a unilateral burn and 38 (57.6%) patients have bilateral burns. In decreasing order of frequency, the circumstances surrounding the injury are: assaults in 45.5% of cases (n=30), work-related accidents in 32% of cases (n=31), and domestic accidents in 23% of cases (n=15). For grade 1 and 2 burns the time elapsed to reepithelialization appears to be shorter when rinsed with Diphoterine* versus physiological solution (respectively): 1.9+/-1 days versus 11.1+/-1.4 days (p=10(-7)) and 5.6+/-4.9 days versus 10+/-9.2 days (p=0.02). For grade 3 and 4 burns, there are complications in 11 cases (11.6%): 8 corneal opacities and 3 perforations. CONCLUSIONS: This study is the first conducted in humans that takes into account the type of ocular rinse product used in the progressive follow-up study of injuries. The time elapsed to reepithelialization is shorter with Diphoterine* for grade 1 and 2 burns. There are not enough cases of grade 3 and 4 burns to make a conclusion. Diphoterine* seems very effective in terms of its mechanism of action and the experimental and clinical results.

Accidents, Home↗
PubMed2004

Speciation of inorganic and methylated arsenic compounds by capillary zone electrophoresis with indirect UV detection. Application to the analysis of alkali extracts of As2S2 (realgar) and As2S3 (orpiment).

A capillary zone electrophoresis (CZE) method with indirect UV detection was developed to simultaneously separate inorganic and organic arsenic compounds including arsenite (iAsIII), arsenate (iAsV), monomethylarsonate and dimethylarsenic acid (DMAV). 2,6-Pyridinedicarboxylic acid (PDC) and n-hexadecyltrimethylammonium hydroxide (CTAOH) were selected to compose a background electrolyte (BGE), where PDC was used as chromophore and CTAOH functioned as electroosmotic flow (EOF) modifier to reduce/eliminate EOF. The choice of detection wavelength, the optimization of BGE pH, and effects of applied electric field strength and temperature on separation were further investigated. The limits of detection for the targeted analytes were between 0.19 and 0.23 ppm as molecule. Good linearity of more than three orders of magnitude was obtained. Repeatability of migration times and peaks areas were 0.8-1.7 and 3.4-6.9% R.S.D.; whereas reproducibility were 1.2-2.2 and 3.6-7.1% R.S.D., respectively. The established CZE method was then applied to analyze the alkali extracts of realgar (As2S2) and orpiment (As2S3). The main components in both alkali extracts were identified to be iAsIII and iAsV.

Alkalies↗
PubMed2005

Comparative assessment of acid, alkali and salt tolerance in Listeria monocytogenes virulent and avirulent strains.

Listeria monocytogenes is an opportunistic bacterial pathogen of man and animals that has the capacity to survive under extreme environmental conditions. While our knowledge on L. monocytogenes and its ability to sustain within wide pH and temperature ranges and salt concentrations has been largely built on the virulent strains of this species, relatively little is known about avirulent strains in this regard. In this study, we extend our analysis on avirulent L. monocytogenes strains. By subjecting three virulent (EGD, 874 and ATCC 19196) and three avirulent (ATCC 19114, HCC23 and HCC25) strains to various pH and salt concentrations, it was found that L. monocytogenes recovered well after treatment with 100 mM Tris at pH 12.0, and to a lesser extent at pH 3.0. Interestingly, avirulent L. monocytogenes strains showed a somewhat higher tolerance to alkali than virulent strains. This unique feature of avirulent L. monocytogenes strains may potentially be exploited for the development of a rapid technique for differentiation between avirulent and virulent strains. Furthermore, all L. monocytogenes strains tested were resistant to saturated NaCl (about 7 M, or 40% w/v) for a long period of time (20 h and possibly longer). Together, these results highlight that acid, alkali, and/or salt treatments commonly used in food product processing may not be sufficient to eliminate L. monocytogenes, and therefore stringent quality control measures at the beginning and end of the food manufacturing process is essential to ensure that such food products are free of listerial contamination.

Acids↗
PubMed2004

Alkali ingestion predisposes to developing giant mid-esophageal pulsion diverticulum - a report of a medical rarity.

Pulsion diverticulae of the mid-esophagus with unknown etiology are usually asymptomatic and therefore considered incidental findings on chest X-rays, barium swallows, or endoscopic procedures. Diagnosis is often delayed due to the rarity of clinical symptoms. The clinical, radiological, etiological and surgical features in a patient with extraordinary symptomatic giant mid-esophageal pulsion diverticulum with history of alkali ingestion are presented here. Alkali injury may yield asymptomatic strictures and/or acquired weaknesses of the esophageal wall, both of which are known to lead to the formation of this giant malady. Putative pathomechanism and suggested therapy including diverticulectomy is proposed in this communication.

Aged↗
PubMed2005

Role of the anion in the alkali halides interaction with D-ribose: a 1H and 13C NMR spectroscopy study.

The alkali halides interaction with d-ribose in D2O solutions was studied by 1H and 13C NMR spectroscopy. The observed changes in the NMR spectra are interpreted according to a model in which the hydroxyls rich region, from C1 to C4, interacts with the cation while the CH2 group at C5 on the opposite side of the sugar interacts with the anion. It seems, during the salt-sugar interaction, cation and anion preserve, at least partially, their ion-pair character. The cooperative interaction of the sugar hydroxyl groups with the cation leads to a polarization within the sugar molecule, which favors the anion interaction with its most positive region. A correlation between the chemical shift of C5 atom and the atomic number of the anion was observed, which is discussed as a neighboring paramagnetic effect; as higher is the halogen atom more pronounced is the resulting shift of the C5 signal. The anion effect is weak but also observed in the 13C signals of those carbon atoms bound to hydroxyl groups where the interaction is predominant with the cation. The 1H signal of the anomeric protons and the relative population of isomers in the alkali halide solution also show an anion dependence.

Alkalies↗
PubMed1997

Preventing symblepharon formation with a gelatin sponge in the eye of a patient with an alkali burn.

PURPOSE: To report a patient with symblepharon caused by an alkali injury whom we treated by using a gelatin sponge. METHODS: Four days after the burn, a gelatin sponge was inserted into the upper conjunctival sac to separate the raw conjunctival surfaces. RESULTS: The gelatin sponge adhered to the tarsal side of the upper fornix and was kept there for 11 days until no epithelial defect was visible in the bulbar conjunctiva. No symblepharon formation was observed 6 months after the injury. CONCLUSION: Application of a gelatin sponge proved to be a simple and effective way of preventing symblepharon formation after an alkali burn.

Alkalies↗