Intrapericardial instillation of sodium hydroxide: failure to produce pericardial symphysis

Previously reported clinical studies have suggested sodium hydroxide as an effective agent in causing pleural symphysis. To explore the sclerosing potential of this agent, we instilled 0.5% sodium hydroxide into the pericardium of four dogs. Normal saline was instilled into the pericardium of one control dog. Echocardiograms, 24 hour EKG monitoring and intracardiac pressures were recorded. One dog was sacrificed at the end of 24 hours, another at the end of seven days and three other dogs were sacrificed at the end of 28 days. ST elevations and prolonged episodes of supra-ventricular and ventricular tachycardia were noted during and within 24 hours after the intrapericardial instillation of sodium hydroxide in all the dogs. No arrhythmias were noted in the control dog. None of the dogs showed pericardial symphysis. These results suggest that sodium hydroxide causes serious cardiac arrhythmias when instilled intrapericardially and is of limited value in causing pericardial symphysis.     

Protective effects of melatonin against caustic esophageal burn injury in rats

Abstract:  Caustic ingestion is one of the most life-threatening events in the pediatric age group, which requires the immediate management and subsequent treatment of its most significant complication, i.e. alterations in esophageal structure. We investigated whether melatonin could reduce the esophageal burn damage induced by sodium hydroxide. It was assumed that melatonin could be effective because of its function as a direct free radical scavenger, its antioxidative actions and its ability to diminish tissue hydroxyproline (HP) levels. Esophageal burns were induced in male rats by the administration of 10% sodium hydroxide. Lipid peroxidation (LPO) products were then measured at the following times: 0, 1, 6, 24, 48 and 72 hr after treatment. Tissue HP concentrations in the injured area were assessed at 14 days after the administration of sodium hydroxide. The groups received either systemic melatonin or normal saline. There were two, non-ischemic, sham control groups treated with or without melatonin. LPO products, malondialdehyde (MDA) and 4-hydroxyalkenal (4-HDA), increased immediately after the administration of sodium hydroxide; this indicates the participation of free radicals in the development of damage. Melatonin diminished the oxidative response and the amount of HP in the late phase of the lesion. Melatonin reduced oxidative damage in the early phase of the esophageal burns induced by sodium hydroxide.     

Rheology of Alkali-Activated Blended Binder Mixtures

Alkali-activated cement (AAC) is an alternative cement that has been increasingly studied over the past decades mainly because of its environmental benefits. However, most studies are on heat-cured AACs and are focused on mechanical properties. There is a lack of research on the fresh properties of ambient-cured AAC systems. This study investigates the rheological properties of ambient-temperature-cured alkali-activated blended binder mixtures activated with sodium silicate and sodium hydroxide solutions. The influence of binder amount, alkaline solid to binder ratio (AS/B), sodium silicate to sodium hydroxide solids ratio (SS/SH), and total water content to total solid (from the binding materials) ratio (TW/TS) on the rheological properties are investigated. The effect of borax as an admixture and silica fume as a replacement for fly ash is also investigated. The results showed that both the yield stress and plastic viscosity are mainly affected by the binder content and TW/TS ratio decreasing with the increase of each parameter. The yield stress increased with the increase of the SS/SH ratio. Borax significantly reduced the yield stress, while silica fume’s effect was dependent on its dosage.     

The effect of sodium bicarbonate versus aluminum-magnesium hydroxide on postprandial gastric acid in duodenal ulcer patients

When ingested 1 hour after a meal, conventional liquid antacids have a buffering effect of approximately 2 hours, while in the fasting state their effect is brief, lasting less than 1 hour. We tested the hypothesis that equal doses of antacid, one water soluble (sodium bicarbonate) and the other water insoluble (aluminum hydroxide plus magnesium hydroxide, MaaloxR), would have similar durations of postprandial buffering if the water soluble antacid regenerates the particulate protein buffer of the meal that leaves the stomach more slowly than liquids. Tests were conducted in random order on three separate days in 10 patients with duodenal ulcer. The effects of 30 ml of 2.39 M sodium bicarbonate (6.17 g, about 1 teaspoonful), the aluminum-magnesium antacid, each equivalent to 71.7 mmol of in vitro buffer, and water as a control on pH, hydrogen ion activity, and titratable acidity were compared. Thirty milliliters of each was swallowed 1 and 3 hours after ingestion of a standard solid plus liquid. Compared to the water control each dose of sodium bicarbonate significantly increased intragastric pH and decreased hydrogen ion activity and titratable acidity for only 1 hour. Each dose of the aluminum-magnesium antacid significantly buffered intragastric contents for 2 hours. These findings indicate that sodium bicarbonate transiently buffers postprandial intragastric contents. Therefore, sodium bicarbonate fails to reconstitute the protein buffer of the meal effectively, and the observations suggest that it leaves the stomach rapidly with the liquid phase of the meal. However, the water insoluble, aluminum-magnesium antacid has a longer duration of buffering, probably because it leaves the stomach more slowly, largely with the solid portion of the meal.     

Preventing nickel-titanium rotary instrument from breakage by continuous irrigation with different fluids during root canal preparation

To study the effect of continuous irrigation of rotating nickel-titanium instrument with several common clinical fluids on the diameter, breaking length and breaking position of nickel-titanium instrument, so as to provide some reference and theoretical basis for clinical operation and instrument improvement.A standardized curved root canal model was established, and ProTaper Universal (PTU) F1 instrument was selected for root canal preparation. The nickel-titanium F1 instrument was flushed with distilled water, 0.9% NaCl, 0.2% chlorhexidine, 1% sodium hypochlorite and 5% sodium hypochlorite, and the diameter, length and position of the instrument before and after breakage were recorded.Only 5% sodium hypochlorite influenced the diameter of 6 mm marker points under different irrigation conditions (P < .05). There was no statistical difference in the length of broken instruments among all the groups, and torsional deformation mainly occurred at the end of broken instruments. The broken positions of instruments in all the groups were located at the bending segment of the root canal. The breaking frequency of the 5% sodium hypochlorite group was the highest in the area 3–5.5 mm away from apical foramen, while the other 4 groups had the highest breaking frequency in the area 0 to 1.5 mm away from apical foramen.External irrigation with different fluids did not influence the breaking length of instruments. The closer to the apical foramen was, the higher the breaking frequency of instruments was. However, only 5% sodium hypochlorite can affect the diameter of rotary nickel-titanium instruments, and may lead to early breakage of the instrument, indicating that the use of disinfectants, except 5% sodium hypochlorite, cannot reduce breakage resistance of nickel-titanium instrument compared with distilled water flushing. Furthermore, 5% hypochlorite could not be recommended for irrigation in clinical practice.     

Evidence for interference with the intestinal absorption of levothyroxine sodium by aluminum hydroxide.

A patient with hypothyroidism who was euthyroid on a fixed-dosage, long-term maintenance regimen of levothyroxine sodium developed persistently elevated serum thyrotropin levels while receiving an aluminum hydroxide-containing antacid. The thyrotropin levels returned to normal shortly after cessation of the antacid therapy. These observations indicate that aluminum hydroxide may interfere with the bioavailability of thyroxine. The thyroid function of patients who are receiving replacement or suppressive thyroxine therapy should be monitored following the commencement of concurrent treatment with medications containing aluminum hydroxide.     

Comparison of three methods for decontamination of faeces for isolation of Mycobacterium tuberculosis.

Sputum and faeces were obtained from 276 patients on admission to a study of drug resistance in Hong Kong. Acid-fast bacilli were detected microscopically in 103 (37%) sputum specimens and 135 (49%) yielded Mycobacterium tuberculosis on culture. Three methods were used to decontaminate faeces prior to dilution and culture in selective liquid Kirchner medium. A total of 61 faecal specimens were positive for M. tuberculosis on culture and, of these, pretreatment with sodium hydroxide yielded 60 (98%), Portaels modification of Wolinsky and Rynearsons's method 28 (46%) and the combined use of benzalkonium chloride and 1-hexdecylpyridinium chloride yielded 32 (52%). It is recommended that faeces should be treated with sodium hydroxide followed by dilution and culture in selective media, although it may be necessary to formulate new selective media for mycobacterial species other than M. tuberculosis.     

骨盐除氟剂的高温再生研究(摘要)

由饮水摄入过量氟所致的地方性中毒目前仍是我国和世界上一些地区的严重的公共卫生问题。作为一种粗制骨盐的骨炭可用来降低饮水中氟含量达到饮水标准。但是，频繁的再生且需较多的氢氧化钠作为再生剂，不仅使水处理费用高且家庭除氟中也难以掌握。基于骨盐中的氟可在250－550℃高温下释放的现象，我们研究了一种对已结合较多氟的骨盐再生方法。以再生后骨炭的除氟容量为指标，研究了不同温度下再生规律。350℃和425℃处理的两组除氟容量均高于氢氧化钠组。用350℃处理0．5－24h，除氟容量为2.57-4.05mg/g，有随着处理时间延长而上升的倾向。但在425℃组，其范围为2.74-4.84mg/g，峰值4.84mg/g位于处理1h处。在相同条件下，骨炭和再生骨盐两再生后的除氟容量相似。在家庭除氟中此法为经济有效的再生方法。     

Pancreatic enzyme replacement

The effect of the addition of sodium bicarbonate, aluminum hydroxide, magnesium hydroxide, calcium carbonate, or cimetidine to supplemental pancreatic enzyme therapy was investigated in patients with severe exocrine pancreatic insufficiency. Steatorrhea was reduced with the administration of three enzyme tablets with meals (73 vs 29 g/24 hr). The coadministration of enzyme tablets with either sodium bicarbonate (16.6 g/24 hr,P=0.08), or aluminum hydroxide (18.4 g/24 hr,P=0.029) yielded a greater reduction in steatorrhea than enzymes alone (29 g/24 hr). Neither magnesium-aluminum hydroxide (36.3 g/24 hr,P=0.22), nor calcium carbonate (39.0 g/24 hr,P=0.029), improved efficacy of enzyme therapy and, in fact, tended to enhance steatorrhea. With the administration of cimetidine there was no significant effect on steatorrhea compared to enzymes alone (32.1 vs 29 g/24 hr,P>0.3). Intraduodenal lipase activity following test meals was found to be a poor predictor of the effectiveness of antacid therapy in improving the efficacy of supplemental enzymes.This study was supported in part by a NIH grant RRO-0350. Computational assistance was provided by the CLINFO Project, funded by the Division of Research Resources of the NIH (RRO-0350).     

Obstructive lung injury after treating wood with sodium hydroxide

Corrosive lung injuries caused by exposure to sodium hydroxide have seldom been described. A formerly healthy 25-year-old developed irreversible obstructive lung injury after working for one day with a caustic soda treatment of wood in a poorly ventilated room.     

Metabolic alkalosis due to absorption of “nonabsorbable” antacids

In a patient with end-stage renal disease undergoing long-term maintenance hemodialysis, moderately severe metabolic alkalosis developed in the absence of vomiting or gastric drainage. The cause of the acid-base disorder was exogenous alkali administration, in the form of combined ingestion of “nonabsorbable” antacids (aluminum hydroxide and magnesium hydroxide), neutral phosphate, and a cation-exchange resin (sodium polystyrene sulfonate). In this report, the relevant data of this patient are detailed, and the literature on this well-documented, albeit poorly recognized, acid-base derangement is summarized.     

减少分枝杆菌培养污染的方法学研究

目的减少分枝杆菌培养过程中出现的污染问题,以提高分枝杆菌的检出率。方法对污染标本进行细菌学培养,了解某时期污染标本的微生物分布情况,并根据分离出的优势污染株有针对性地在该时期对送检标本改用酸性前处理剂或加大氢氧化钠的浓度进行样品的前处理,且与常规的前处理方法进行对比研究。结果对主要由革兰阴性肠道科细菌引起的污染,改用5%硫酸做前处理剂,以及对由革兰阳性菌(包括酵母样菌属等)引起的污染,加大氢氧化钠的浓度,可使培养过程中出现的污染率由6.5%下降至2.4%。结论对某时期的污染标本进行细菌学培养与分析,并有针对性地在此阶段对样品改用酸性前处理剂或加大氢氧化钠的浓度,可以有效地减少在培养分枝杆菌过程中出现的污染情况。     

Interaction of woodchuck hepatitis virus surface antigen with hepatocyte plasma membrane in woodchuck chronic hepatitis

The extent of association between woodchuck hepatitis virus surface antigen and host hepatocyte plasma membrane in chronic hepatitis was studied. Purified membranes containing the antigen were treated with various agents which perturb plasma membrane constituents to elute woodchuck hepatitis virus surface antigen. The products from disrupted membranes were analyzed by sedimentation in sucrose gradients and tested to identify the antigen reactivity. The results indicated that membrane-bound woodchuck hepatitis virus surface antigen was partially released by 4 M potassium chloride, potassium thiocyanate and guanidine, 6 M urea or 0.1 N sodium hydroxide (pH 13.5), but not in the presence of low concentrations of these reagents or by 10% 2-mercaptoethanol and 1% sodium dodecyl sulfate. No more than 15% of the total membrane-associated woodchuck hepatitis virus surface antigen was eluted by 0.1 N NaOH, which was found to be the most effective eluent among tested agents at the antigen removal. The remaining woodchuck hepatitis virus surface antigen was resistant to further extraction with sodium hydroxide, as expected for an integral membrane protein. Treatment of the infected membranes with 1% Triton X-100 or 50 mM deoxycholic acid, that solubilize the membrane lipid bilayer releasing most of the integral membrane proteins, resulted in the sedimentation of almost all detectable woodchuck hepatitis virus surface antigen reactivity with the detergent-insoluble membrane residues, suggesting a firm interaction of the antigen with the plasma membrane matrix.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gastric cytoprotection by antacids and papaverine in rats

Prostaglandin E2 (PGE2) prevented hemorrhagic ulceration of rat stomach mucosa induced by various procedures when given orally at a non-antisecretory dose. This effect of PGE2 is called gastric cytoprotection. We used absolute ethanol, 0.6 N hydrochloric acid and 0.2 N sodium hydroxide as damaging agents. Ranitidine at an antisecretory dose did not exhibit any cytoprotective effect. However, the poorly absorbable antacids, magnesium hydroxide plus aluminium hydroxide and aluminium phosphate inhibited the development of hemorrhagic lesions significantly. A similar protective effect was seen after intragastric administration of papaverine, which is known to stimulate endogenous prostaglandin synthesis. However, the question as to whether or not stimulation of endogenous prostaglandin synthesis is the mode of action of the cytoprotective effect of papaverine and poorly absorbable antacids, cannot yet be answered.     

Effects of several virucidal agents on inactivation of influenza, Newcastle disease, and avian infectious bronchitis viruses in the allantoic fluid of chicken eggs

General theories on the inactivation of viruses in the presence of a concentrated protein, such as the allantoic fluid of chicken eggs, are not useful. That is, although sodium hypochlorite and sodium hydroxide are generally known as strong virucidal agents, they do not sufficiently inactivate viruses in allantoic fluid. We found that benzalkonium chloride (BC) is an effective virucidal agent against influenza, Newcastle disease, and avian infectious bronchitis viruses even in the presence of a concentrated protein. BC is easily biodegradable by activated sludge and is not very harmful to humans. We strongly recommend BC as a useful virucidal agent, especially in the manufacture of vaccines for these viruses.     

Life Cycle Assessment and Impact Correlation Analysis of Fly Ash Geopolymer Concrete

Geopolymer concrete (GPC) has drawn widespread attention as a universally accepted ideal green material to improve environmental conditions in recent years. The present study systematically quantifies and compares the environmental impact of fly ash GPC and ordinary Portland cement (OPC) concrete under different strength grades by conducting life cycle assessment (LCA). The alkali activator solution to fly ash ratio (S/F), sodium hydroxide concentration (C_NaOH), and sodium silicate to sodium hydroxide ratio (SS/SH) were further used as three key parameters to consider their sensitivity to strength and CO₂ emissions. The correlation and influence rules were analyzed by Multivariate Analysis of Variance (MANOVA) and Gray Relational Analysis (GRA). The results indicated that the CO₂ emission of GPC can be reduced by 62.73%, and the correlation between CO₂ emission and compressive strength is not significant for GPC. The degree of influence of the three factors on the compressive strength is C_NaOH (66.5%) > SS/SH (20.7%) > S/F (9%) and on CO₂ emissions is S/F (87.2%) > SS/SH (10.3%) > C_NaOH (2.4%). Fly ash GPC effectively controls the environmental deterioration without compromising its compressive strength; in fact, it even in favor.     

A simple and improved method for diagnosis of tuberculosis using hypertonic saline and sodium hydroxide to concentrate and decontaminate sputum

We report the use of hypertonic saline and sodium hydroxide (HS-SH) for concentration-decontamination of sputum samples for the diagnosis of tuberculosis. This method increases detection of mycobacteria in smears compared to examination of direct smears, is comparable and reduces contamination in cultures compared to NALC-NaOH.     

Analysis of fibres recovered from lung tissue

The sodium hypochlorite and potassium hydroxide procedures commonly used to recover inorganic fibres from lung tissue have been examined to determine the magnitude of any fibre loss and whether the loss is size-dependent. A UICC amosite of known weight and fibre concentration was treated using the above techniques with and without the presence of lung tissue. The potassium hydroxide and sodium hypochlorite techniques caused a reduction of 27% and 39%, respectively, in the number of fibres recovered. The loss was not uniform throughout the fibre size range: there were proportionally fewer fine short fibres and more long fibres. An additional serial centrifugation experiment using glass microfibre, rockwool, anthophyllite and amosite showed that substantial losses of fibres occurred with repeated centrifugations and resuspensions. The losses were independent of fibre size. In the case of glass microfibre following an initial sharp fall, there was an increase in fibre number following serial centrifugations. The final figure for recoverable fibres in routine examinations of lung tissue represents a mixture of fibre losses and fibre gains, the extent of which depends on the various preparation steps and techniques used. The data reported here indicate that the commonly used digestion techniques produce a distorted estimation of the fibre load of the lung which makes it difficult to obtain an accurate determination.     

Acidic and Basic Solutions Dissolve Protein Plugs Made of Lithostathine Complicating Choledochal Cyst/Pancreaticobiliary Maljunction

Background Symptoms of choledochal cysts are caused by protein plugs made of lithostathine, which block the long common channel and increase pancreaticobiliary ductal pressure. Agents that dissolve protein plugs can provide relief from or prevent symptoms. In the present study, drugs reportedly effective for pancreatic and biliary stones were used in dissolution tests. Methods Protein plugs were obtained from choledochal cysts during surgery in two children (5- and 6-year-old girls). Plugs approximately 2 mm in diameter were immersed in citric acid, tartaric acid, dimethadione, bromhexine, dehydrocholic acid, sodium citrate, hydrochloric acid, and sodium hydroxide solutions under observation with a digital microscope. The pH of each solution was measured using a pH meter. Results Plugs dissolved in citric acid (5.2 mM; pH 2.64), tartaric acid (6.7 mM; pH 2.51), dimethadione (75 mM; pH 3.70), hydrochloric acid (0.5 mM; pH 3.13), and sodium hydroxide (75 mM; pH 12.75) solutions. Plugs did not dissolve in dimethadione (7.5 mM; pH 4.31), bromhexine (0.1%; pH 4.68), dehydrocholic acid (5%; pH 7.45), and sodium citrate (75 mM; pH 7.23) solutions. Conclusion Protein plugs in choledochal cysts are dissolved in acidic and basic solutions, which may eliminate longitudinal electrostatic interactions of the lithostathine protofibrils.     

Alkaline chemical burn to the face requiring full-thickness skin grafting

A case of a patient with an alkaline chemical burn to the face from the misuse of the aerosol form of an oven cleaner is presented. The low concentration of sodium hydroxide and lack of early pain delayed the patient's presentation to the emergency department for two hours. After this delay in seeking treatment, continuous irrigation in the ED did little to modify the pH of the patient's injured skin. Thus, she developed a full-thickness alkaline burn that eventually required skin grafting.