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PubMed1987

Simplified acetylcysteine-alkali digestion-decontamination procedure for isolation of mycobacteria from clinical specimens.

During our attempts to reevaluate and improve mycobacteriology laboratory procedures, we found that isolation of mycobacteria from undecontaminated specimens through the use of selective media was unrewarding and that specimen decontamination was an essential step. A reevaluation of the N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) decontamination procedure (G. P. Kubica, W. E. Dye, M. L. Cohn, and G. Middlebrook, Am. Rev. Respir. Dis. 87:775-779, 1963) indicated that this method could be simplified and shortened without affecting the isolation rate or growth and without increasing the contamination rate. The modified NALC-NaOH procedure effectively combines the decontamination step with the concentration step: specimens are mixed with the NALC-NaOH solution on a Vortex mixer and, without any waiting or addition of buffer or water to the digested specimens, centrifuged at 3,000 X g for 15 min, and the sediment is suspended in phosphate buffer (pH 5.3). The modified method is simpler, faster, and safer than the original procedure, and the reduced manipulation is also likely to minimize the chance for cross-contamination in sequential specimen processing. The total alkali exposure time in the modified NALC-NaOH method should be kept to a minimum; if necessary or feasible, the concentration of NaOH in the digestion solution may be reduced from the usual strength of 2% to about 1.5% to compensate for the longer alkali exposure time in the modified method to maintain the isolation rate or to improve it.

Acetylcysteine↗

PubMed1986

Biological activity and electron microscopy of poliovirus 14S particles obtained from alkali-dissociated procapsids.

Highly purified 14S subunit particles were obtained from alkali-dissociated poliovirus type 1 procapsids (naturally occurring empty capsids in poliovirus-infected cells) to compare their morphological and biophysical properties with those of naturally occurring 14S particles. Procapsid-derived 14S particles (PC-14S), like naturally occurring 14S particles, were capable of self-assembly into an empty shell in buffer or extracts from uninfected cells. These empty capsids always exhibited pIs more acidic than those of procapsids but were themselves distinguishable by their respective pIs. Nevertheless, if PC-14S or naturally occurring 14S particles were incubated with extracts made from poliovirus-infected cells, procapsidlike empty shells were formed. This clearly showed that the 14S particle, however obtained, possesses the information to form an empty shell of correct dimensions but of improper conformation, unless a factor present in poliovirus-infected cells is present. With the electron microscope, the PC-14S subunit frequently was seen as a pentagonal structure with a diameter of 20.4 +/- 1.4 nm, a size somewhat larger than expected for a subunit composing 1/12th of the poliovirus surface. Upon self-assembly in vitro, the empty shell formed exhibited a diameter of 29 +/- 1 nm and a wall thickness of ca. 6 to 7 nm. It was necessary to avoid CsCl banding of procapsids in their preparation as this treatment altered both their pI and their sensitivity to alkali dissociation into 14S subunits. The relevance of these findings to the nature and role of procapsids and the requirement for a morphopoietic factor in poliovirus morphogenesis is discussed.

Capsid↗

PubMed1988

Upstream regulatory region for inducible expression of the chicken skeletal myosin alkali light-chain gene.

The expression of the fast type of myosin alkali light chain 1 is induced during the differentiation of muscle cells. To study the mechanism of its gene regulation, we joined the sequence of the 5'-flanking and upstream region of the chicken myosin alkali light-chain gene to the structural gene for chloramphenicol acetyltransferase (CAT). The fusion gene was introduced either into quail myoblasts transformed by a temperature-sensitive mutant of Rous sarcoma virus (tsNY68) or into chicken myoblasts, and the transiently expressed CAT activity was assayed after the differentiation of the myoblasts. From the experiments with the external and internal deletion mutants of the fusion gene, the cis-acting regulatory region responsible for the enhanced expression of the CAT activity in response to the cell differentiation was found to be localized at 2 kilobases upstream of the transcription initiation site. This region of 160 nucleotides contained two pairs of short sequences worthy of note, a direct repeat of 12 nucleotides, and an inverted repeat of 8 nucleotides. The nucleotide sequences of the 5'-flanking sequence up to nucleotide -3381 were determined and compared with those of the upstream activating elements of actin genes.

Animals↗

PubMed1976

Renal biopsy in the milk-alkali syndrome.

In milk-alkali syndrome the degree of renal impairment varies greatly. Few reports have been published describing structural changes on renal biopsy. In three illustrative cases, impairment of renal function was related to morphological changes shown on percutaneous biopsy. Milk-alkali syndrome should be considered as a cause of renal dysfunction in patients with a long history of dyspensia.

Adult↗

PubMed1990

Effect of alkali treatment on physiological activity of cotton condensed tannin.

Cotton dusts contain condensed tannins and endotoxins, which are suspected of contributing to the development of acute and chronic biological responses in some cotton textile mill workers. Condensed tannin extracted from cotton dust was coated on to cellulose powder, and the tannin coated powder was treated with an alkali solvent system previously developed to reduce the endotoxin content and pulmonary toxicity of cotton dust. Physiological activities of the dusts and powders were compared by assaying the production of the arachidonic acid metabolites prostaglandin F2 alpha (PGF2 alpha), thromboxane A2 (TxA2) (the precursor to thromboxane B2 (TxB2], leukotriene C4 (LTC4), and prostaglandin E2 (PGE2) by guinea pig pulmonary cells obtained by lung lavage. Cotton dust stimulated the pulmonary cells to produce a total of 29 pg metabolites per 10(6) cells. Production of metabolites by cells stimulated with tannin coated cellulose powder was reduced to 8.3 pg/10(6) cells. Alkali treatment of the tannin coated cellulose powder resulted in a further decrease in its ability to stimulate the cells, producing 3.5 pg metabolites per 10(6) cells. The ability of the dusts and powders to stimulate production of metabolites of arachidonic acid by pulmonary cells from guinea pigs was highly correlated with tannin content of the materials, but not with endotoxin content as measured by the Limulus amoebocyte lysate (LAL) assay.

Animals↗

PubMed2000

Milk alkali syndrome-an unusual syndrome causing an unusual complication.

Milk alkali syndrome is rare and although pancreatitis secondary to hypercalcaemia is well recognised, there has only been one other reported case of pancreatitis secondary to the milk alkali syndrome. Such a case, caused by self medication of over the counter medication, is reported.

Acute Disease↗

PubMed1975

The effect of growth environment on the chloroform-methanol and alkali-extractable cell wall and cytoplasm lipid levels of Mucor rouxii.

The distribution of chloroform-methanol and alkali-extractable lipids in the cell walls of aerobically grown filamentous cells from Mucor rouxii has been determined. The results have been compared with the corresponding lipid composition of yeast-like cells from M. rouxii, which can be produced in two ways: by growth under anaerobic conditions and by aerobic growth in the presence of 0.22% phenethyl alcohol (PEA). It was observed that in most cases the crude cytoplasmic fraction contained higher levels of several lipids (i.e., squalene, sterols, triterpenes, and fatty acids) than did the corresponding cell walls. The cell walls did, however, contain both "free" (chloroform-methanol extractable) and "bound" (alkali extractable) lipids although the relative amounts were markedly dependent on the cell growth environment. The aerobically grown filamentous cell walls contained higher levels of squalene, sterols, triterpenes, and fatty acids than did aerobically grown yeast-like PEA-induced cell walls and there was also considerable variation in the "free"/"bound" ratios of the various lipid components. The lipid levels in both the cell walls and cytoplasm of the anaerobically grown cells were considerably lower than those of the cells grown under aerobic conditions. In addition, the differences in the growth environment were also reflected in the compositions of the individual lipid fractions from both the cell wall and the cytoplasm fraction.

Aerobiosis↗

PubMed2001

Surface femtochemistry: observation and quantum control of frustrated desorption of alkali atoms from noble metals.

This review presents a case study of the direct, real-time observation of a surface photochemical reaction, namely the frustrated photodesorption of alkali atoms from noble metal surfaces. Charge transfer excitation of an electron from the metal substrate into an unoccupied resonance of the alkali atom instantaneously turns on the repulsive Coulomb force inducing the nuclear motion of both the adsorbate and substrate atoms. The incipient nuclear wave packet dynamics are documented for the case of Cs/Cu(111) through the accompanying change in the surface electronic structure. The intimate view of atoms attempting to escape the surface bond highlights the unique role of the substrate in the electronic and nuclear dynamics that ultimately determine the product yields. Moreover, slow dephasing of the coherent polarization is exploited to demonstrate the control of nuclear wave packets through the phase of the excitation light.

Journal Article↗

PubMed1975

Gastric bullae. An early roentgen finding in corrosive gastritis following alkali ingestion.

In most cases of alkali ingestion, the stomach is protected from injury by its contents and gastric acidity, so that the esophagus is usually the main site of injury. The authors describe a case of severe corrosive gastritis following ingestion of a large amount of alkali. Huge gastric bullae, an unusual manifestation, were an early roentgen finding. As healing occurred, the stomach was reduced to a shrunken, aperistaltic pouch.

Blister↗

PubMed1975

Mechanisms of disposal of acid and alkali in rabbit duodenum.

Stripped duodenal mucosa of rabbits was mounted in Ussing chambers containing a Ringer solution gassed with 100% O2. The disappearance of acid or alkali from the mucosal solution of short-circuited tissue was measured with a pH stat while the serosal pH was kept at 7.4. The duodenum rapidly disposed of both acid and alkali; neither property was altered by gassing with N2 while iodoacetate was in the perfusing solutions. Prevention of release of CO2 from the mucosal chamber obliterated the early rapid phase of acid disposal by the mucosa while a similar maneuver in the serosal chamber increased the appearance of serosal acid without altering the rate of acid disposal. Gut sacs of rabbit duodenum in vitro and in vivo showed a positive correlation between acid disposal and the rate of luminal CO2 production. While acid disposal progressively decreased with time for the in vitro gut sacs, the in vivo gut sac showed no fatigue in this respect. Luminal acidification in the Ussing chamber was associated with a profound reduction in short-circuit current (Isc), partially reversible by elevation of the mucosal pH but not by luminal glucose. Our data suggest that acid disposal occurs in part by intraluminal neutralization and in part by diffusion into the mucosa.

Acid-Base Equilibrium↗

PubMed1983

Hydrogen ion secretion by the rat distal nephron: adaptation to chronic alkali and acid ingestion.

Isolated rat kidneys perfused at a low bicarbonate concentration were subjected to increased rates of buffer excretion, provided as creatinine, in order to examine the maximal hydrogen ion secretory capacity of the distal nephron. Preliminary experiments with kidneys from normal rats indicated that the quantity of hydrogen ion that titrated creatinine from urine pH to a pH of 6.0, designated TA-pH 6.0, provided an index of net hydrogen ion secretion by a functional segment of the distal nephron. With this technique the response of distal nephron hydrogen ion transport to ingestion of both acid and alkali loads was examined. Perfused kidneys from rats with chronic metabolic acidosis, produced by drinking 1.5% NH4Cl for 3-5 days, excreted urine with a lower pH and higher total titratable acid and TA-pH 6.0 than appropriate controls. Perfused kidneys from rats that ingested NaHCO3 for 7 days exhibited a higher urine pH and lower rates of total titratable acid and TA-pH 6.0 than controls. By contrast, kidneys from rats acutely tube-fed NaHCO3 3 h prior to study showed no change in urinary acidification parameters. Thus, chronic ingestion of an acid load stimulates, and chronic ingestion of an alkali load inhibits, the intrinsic hydrogen ion secretory capacity of the rat kidney at a distal nephron site. This intrinsic adaptation of the hydrogen ion transport mechanism is not secondary to changes in aldosterone because rats that ingested NaHCO3 chronically had higher plasma aldosterone levels than controls.

Acclimatization↗

PubMed1984

Effect of ascorbic acid on ulceration in alkali-burned corneas.

Alkali-burned corneas were treated with 2% ascorbic acid. Topical applications and subconjunctival injections were given for 32 days. Treatment with ascorbic acid significantly decreases the incidence of corneal ulcerations and perforations compared to the control group that received the vehicle. These results confirm previous studies and strongly suggest that ascorbic acid presents a potential for use in the alkali-burned human eye.

Animals↗

PubMed1995

Type IV collagen in the basement membrane of the corneal epithelium after alkali burns in guinea pigs.

To investigate the changes in the corneal epithelial basement membrane following an alkali burn, we examined the immunolocalization of type IV collagen and laminin in the eye of the guinea pig burned with alkali. The burn damaged the corneal, limbal and conjunctival epithelium. After regeneration, basement membrane was interrupted, as indicated by laminin immunoreactivity. Type IV collagen immunoreactivity was transiently expressed in the early healing phase in the epithelial derived from both the cornea and conjunctiva, but was not seen in the normal corneal epithelial basement membrane. Later in the healing process, following transdifferentiation of the conjunctival epithelium into a cornea-like epithelium, its type IV collagen immunoreactivity was weaker than that in the basement membrane of the nontransdifferentiated epithelium. Conjunctival transdifferentiation during healing may have led to transient development of type IV collagen immunoreactivity.

Animals↗

PubMed2003

Hypercalcemia and peptic ulcer disease-related Milk-alkali syndrome.

Milk-alkali syndrome was considered "extinct" by 1985 because of the advent of non-alkaline ulcer medications (ie, histamine-2 receptor blockers and proton pump inhibitors). At that time, it was thought to cause <1% of hypercalcemia, which occurred when one ingested a sufficient quantity of calcium and alkali together. This case emphasizes the importance of considering this syndrome in patients who self-medicate for control of symptoms related to gastroesophageal reflux and peptic ulcer disease and for those using calcium supplementation for prevention or treatment of osteoporosis.

Journal Article↗

PubMed1995

Pathology of experimentally induced chronic selenosis (alkali disease) in yearling cattle.

Prolonged oral exposure of cattle to elevated dietary selenium (Se) in forage and seleniferous plants in seleniferous areas of the western United States is associated historically with 2 clinical syndromes: alkali disease and "blind staggers." The potential for Se-induced disease in cattle and other species is considerable in areas with seleniferous shales, Se-accumulating plants, arid climates, and alkaline soils. These 2 Se-associated conditions were defined in the 1930s and 1940s, and the nosology of blind staggers is questionable. Seventeen yearling steers fed 0.15, 0.28, and 0.8 mg Se/kg body weight as selenomethionine or selenite for 120 days were euthanized and examined postmortem. Significant lesions were confined to 4 steers in the medium- and high-dose selenomethionine group and to 1 steer in the high-dose selenite group. Grossly, dystrophic hoof lesions developed in 2 steers, 1 of which had extensive separation of horn from lamellar and coronary epidermis and also lost hair from the tail switch. Histologically, tubules in the stratum medium of hooves from these 5 steers were replaced by islands of parakeratotic cellular debris, separated by more normal hoof matrix. Two of the 5 steers also had hyperplasia, acanthosis, parakeratosis, and disorganized germinal epithelium of varying severity in hoof epithelium, particularly at the tips of epidermal lamellae. These changes may distinguish the hoof lesions of chronic selenosis from those of chronic laminitis in cattle, in which dermal (chorial) changes predominate. In skin from the distal part of the tail of the animal that lost its switch, most follicles were atrophic and devoid of hairshafts and displayed dyskeratosis and mild superficial follicular keratosis. No significant lesions developed in tissues other than integument. Autometallographic staining for catalytic Se bonds in various tissues, including skin, liver, and kidney, revealed no positive staining of hair shafts; the correlation between stain intensity and dose group was poor. These findings indicate that dietary exposure for 4 months to 0.28 and 0.8 mg Se/kg in the form of selenomethionine and to 0.8 mg Se/kg in the form of sodium selenite reproduces in some cattle mild (subclinical) to severe (clinical) forms of alkali disease. No significant neurological, renal, or hepatic lesions developed, supporting the contention that blind staggers is caused by factors other than excessive dietary selenium.

Animal Feed↗

PubMed2002

Optical properties and quantum efficiency of thin-film alkali halides in the far ultraviolet.

The optical constants of thin films of CsI, KI, and KBr and the quantum efficiency (QE) of planar photocathodes made with these alkali halides in the 53.6-174.4-nm spectral range are presented. The optical constants were obtained from measurements of the reflectance as a function of incidence angle. The effect of film heating and exposure to UV irradiation on the optical properties and on the QE of the three alkali halides was investigated. KBr was found to be the most stable material for both heating and UV irradiation. KI appeared to be close to temperature stable, whereas UV exposure affected its optical constants. CsI optical constants changed after 420 K heating and after UV exposure. The changes in the optical constants were related to the QE changes, and a certain correlation between both variations was determined. However, it was also demonstrated that the QE changes cannot be explained solely by the changes in optical constants.

Journal Article↗

PubMed2001

Coherent broadband light effects in grating spectrometer studies of emission from alkali atoms at surfaces.

With ordinary grating spectrometers, strong bands that are due to broadband coherent light emission from samples containing various amounts of alkali atoms can be observed. The coherent light is proposed to be emitted by the alkali Rydberg states that are easily formed in these systems. The edges of the bands are observed at angles corresponding to low numbers of standing waves along the grating surface and perpendicular to it. This type of band is observed both with thermal sources and with broadband light sources created by pulsed laser light, and it is observed only with s-polarized (TE-mode) light. The band intensities are independent of the entrance slit width in the spectrometer, which shows that strong interference effects exist. The number of interference fringes observed on top of the most intense band is directly proportional to the width of the entrance slit. The time-resolved signal shows that large photon peaks from thermal sources are emitted in bursts within 2 mus, probably corresponding to the lifetime of the emitting Rydberg states and Rydberg clusters.

Journal Article↗

PubMed2004

Continuous monitoring of alkali metals in gas flows using direct-current plasma excited atomic spectroscopy.

A measuring instrument employing direct current (dc) plasma excited atomic line spectroscopy was developed for continuous measurement of alkali in combustion flue gases. Alkali compounds are dissociated by mixing sampled flue gas with a nitrogen plasma jet generated with a non-transferred dc plasma torch. The instrument can be used in two operating modes. The molar fraction is determined either by measuring the transmittance of the gas jet or by monitoring the emission. A tungsten halogen lamp and scanning monochromator are used for the measurement of the optical signals. Measurement of sodium and potassium has been demonstrated. The detection limits of the instrument are 50-70 ppb in the absorption mode. The detection limits are 2-3 ppb at 0.1 MPa pressure and 0.1-0.2 ppb at 1.0 MPa in the emission mode. The instrument is designed to withstand corrosive, particle laden, and pressurized flue gases at temperatures up to 1373 K.

Journal Article↗