Light transmittance and depth of cure of a bulk fill composite based on the exposure reciprocity law

Abstract The objective of this study was to evaluate the effect of the exposure reciprocity law of a multi-wave light-emitting diode (LED) on the light transmittance (LT), depth of cure (DOC) and degree of conversion in-depth (DC) of a bulk fill composite. A bulk fill composite (EvoCeram® bulk fill, Ivoclar Vivadent) was photoactivated using the multi-wave LED (VALO™ Cordless, Ultradent). The LED was previously characterized using a spectrophotometer to standardize the time of exposure when using the Standard or Xtra-Power modes with the same radiant exposure of 20J/cm2. LT was evaluated through samples of the bulk fill composite every millimeter till 4 mm in-depth. DOC was evaluated according to the ISO 4049. DC of the central longitudinal cross-section from each sample of the DOC test was mapped using FT-NIR microscopy. Data were statistically analyzed according to the experimental design (α=0.05; ß=0.2). The radiant exposure in the violet wavelength range for Standard and Xtra-Power was 4.5 and 5.0 J/cm2, respectively; for the blue wavelength range the radiant exposure for Standard and Xtra-Power was 15.5 and 15.0 J/cm2, respectively. There was no statistical difference in the DOC using Standard or Xtra-Power light-curing modes, but the DOC was lower than the claimed by the manufacturer (4 mm). The DC was not significantly affected by the light-curing mode up to 4 mm in depth (p>0.05). According to exposure reciprocity law, the reduction in exposure time using the same radiant exposure did not affect the depth of cure of the bulk fill composite.

Resumo O objetivo deste estudo foi avaliar o efeito da lei de reciprocidade de um diodo emissor de luz (LED) multi-wave na transmitância de luz (LT), profundidade de cura (DOC) e grau de conversão em profundidade (DC) de um compósito bulk fill. Material e Métodos: Um compósito bulk fill (EvoCeram®, Ivoclar Vivadent) foi fotoativado utilizando um LED multi-wave (VALO ™ Cordless, Ultradent). O LED foi previamente caracterizado usando um espectrofotômetro para padronizar o tempo de exposição utilizando os modos Standard ou Xtra-Power com a mesma dose de energia de 20 J/cm 2. A LT foi avaliada através de amostras do compósito bulk fill a cada milímetro até 4 mm de profundidade. O DOC foi avaliado de acordo com a ISO 4049. O DC foi realizado em forma de mapeamento da seção transversal longitudinal central de cada amostra do teste de DOC utilizando microscopia FT-NIR. Os dados foram analisados estatisticamente de acordo com o delineamento experimental (α=0,05; ß=0,2). A exposição radiante na faixa de comprimento de onda violeta para os modos Standard e Xtra-Power foi de 4,5 e 5,0 J/cm2, respectivamente; e para a faixa de comprimento de onda azul, a exposição radiante para os modos Standard e Xtra-Power foi de 15,5 e 15,0 J/cm2, respectivamente. Não houve diferença estatística no DOC utilizando os modos de fotopolimerização Standard ou Xtra-Power, mas o DOC foi menor do que o reivindicado pelo fabricante (4 mm). O DC não foi afetado significativamente pelo modo de fotopolimerização até 4 mm de profundidade (p>0,05). De acordo com a lei de reciprocidade da exposição, a redução no tempo de exposição utilizando a mesma exposição radiante não afetou a profundidade de cura do compósito bulk fill.

Review of Aluminium Phosphide Poisoning

Agricultural revolution and increasing pesticidal use have brought its share of downsides in the form of pesticidal poisoning. Every year approximately 300,000 deaths happen worldwide due to pesticide poisoning. Organophosphates, chlorates, and aluminum phosphide are the commonly used pesticides. Alkaline phosphatase (ALP) is the most lethal among the available pesticides and no antidote is available and aptly called as suicide poison. The common use and easy availability of ALP is causing acute and chronic health effects which have reached major proportions in Asian and Middle Eastern countries such as India, Bangladesh, Iran, Jordan, and Sri Lanka. Toxicity of ALP is related to prompt release of lethal phosphine gas as ALP tablet absorbs moisture. Phosphine gas mainly affects cardiovascular system gastrointestinal tracts, lungs, and kidneys. The clinical features of poisoning include nausea, vomiting, abdominal pain, pulmonary edema, cyanosis shock arrhythmias, and alter sensorium. Diagnosis of ALP poisoning largely depends on history and clinical setting and treatment is usually initiated without waiting for silver nitrate paper test or gastric aspirate analysis. Treatment includes early gastric lavage symptomatic supportive therapy and palliative care. There has been greater understanding about the mechanism and pathophysiology of ALP toxicity over the years, although that cannot be commented about the treatment modalities. Government efforts to restrict sale have been offset by the lack of strict enforcement by regulatory agencies. Case fatality rates from ALP poisoning have shown some decline over the years due to early supportive management. Different treatment modalities and protocols have been tried at various centers with variable success; however, further research for an antidote is the need of the hour.

Progress in treatment of acute aluminum phosphide poisoning / 中华劳动卫生职业病杂志

Aluminum phosphide (ALP) is frequently used for grain conservation despite its high toxicity. In some developing countries increased utilization of ALP has resulted in increment of ALP-attributed poisoning numbers. The mortality of ALP poisoning is extremely high and no effective antidote is available so far. However, the astute survey of potential misconceptions in the course of acute toxicity has led some scientists to introduce novel therapeutic approaches. Meanwhile, some new antioxidants were discovered and expected to be used in the management of ALP poisoning. In addition, the progress in intensive care has promoted technologies such as CRRT, IABP and ECMO for the treatment of ALP poisoning with reported success in alleviating severe toxicity. Recent studies on the therapy of ALP poisoning are reviewed in this article.

Preparation technology of liquiritin based on ultrafiltration-complexation extraction and back extraction technology / 中草药

Objective To establish a complexation extraction and back extraction technology for the separation and purification of liquiritin from Glycyrrhiza uralensis ultrafiltrate. Methods Taking the extraction rate of liquiritin as an index, the optimum composition of complexing extractant was first determined by uniform design, and then orthogonal experiments were used to optimize the conditions of complexing extraction. Taking the back extraction rate of liquiritin as an index, the process conditions for the back extraction of liquiritin were determined by investigating the type and concentration of back extractant. Results The complexation extraction research found that the complexing extractant should be a binary complexing extractant composed of trialkyl phosphine oxide (TRPO) and sulfonated kerosene. The optimum extraction conditions for liquiritin were as follows: TRPO-sulfonated kerosene (9∶91), pH value of G. uralensis ultrafiltrate was adjusted to 4, volume ratio of organic phase to aqueous phase was 1∶1, and average extraction rate of liquiritin reached 99.6%. The study of back extraction process showed that under the condition that the volume ratio of organic phase to back extractant was 1∶1, 17.5 mmol/L NaOH aqueous solution was the best back extractant, and the back extraction rate of liquiritin was 99.3%. Conclusion Under the optimized conditions, the liquiritin in G. uralensis ultrafiltrate can smoothly transfer from the ultrafiltrate to the complexing extractant and then to the alkaline back extractant. The total transfer rate of liquiritin is as high as 98.9%. This paper can provide a new preparation technology for the separation and purification of liquiritin.

Preparation technology of glycyrrhizin acid based on ultrafiltration- complexation extraction technology / 中草药

Objective: To establish a technique for preparing glycyrrhizin acid (GA) by ultrafiltration-complexation extraction. Methods The effect of pH on the extraction rate of GA from ultrafiltrate was investigated in the range of 4-8; The orthogonal test was used to optimize the technological conditions for complexation extraction of GA; The extraction conditions of GA were determined by investigating the type and concentration of the extractant. Results The optimum extraction conditions for GA were as follows: pH value of Glycyrrhiza uralensis ultrafiltrate was adjusted to 2, TRPO-sulfonated kerosene (5:95, volume percent), volume ratio of organic phase to aqueous phase was 1:1, and average extraction rate of GA reached 99.2%. The best back extraction conditions for GA were as follows: 22.5 mmol/L NaOH aqueous solution was used as the stripping agent, the volume ratio of organic phase to stripping agent was 1:1, the single back extraction rate of GA reached 98.8%, and the total transfer rate of GA was 98.1%. Conclusion Ultrafiltration-complexation extraction technology can be used as a new process for the preparation of GA.

Study on technological conditions of complex extraction of isoliquiritin / 中草药

Objective: To investigate the effect of extraction and reverse extraction conditions on the transfer of isoliquiritin. Methods: The extraction rate of isoliquiritin was used as the index to determine the best composition and concentration of complexing extractant. Taking the reverse extraction rate of isoliquiritin as the index, the species and concentration of the reverse extraction agent were investigated, and finally the technological conditions for the extraction and reverse extraction of isoliquiritin from glycyrrhizin ultrafiltration were obtained. Results: The best complexation extraction condition was: the ratio of TRPO to sulfonated kerosene was 7:93, and the extraction rate of isoliquiritin reached 97.60%. The best reverse extraction agent was 0.26% NaOH aqueous solution, and the reverse extraction rate of isoliquiritin reached 95.40%. Conclusion: Under the optimal conditions of extraction and reverse extraction obtained in this experiment, isoliquiritin can be transferred from glycyrrhizin ultrafiltration to complexing extractant and then to alkaline reverse extraction agent, and finally isoliquiritin can be obtained by extraction and reverse extraction.

Serie de casos de intoxicación fatal por ingesta intencional de fosfuro de aluminio: case reports with fatal evolution / Aluminium phosphide poisonings: case reports with fatal evolution

El fosfuro de aluminio (AlP) es un plaguicida fumigante de bajo costo, cuyo único uso permitido es el control de plagas en granos almacenados. En contacto con la humedad del aire libera gas fosfina (PH3), altamente tóxico, inflamable y explosivo, pero que se disipa rápidamente. En todas las presentaciones, 3 g de la formulación genera 1 g de gas fosfina. La exposición a 1000 ppm durante 30 minutos es fatal. Presentamos una serie de casos de intoxicación severa por ingesta intencional de fosfuro de aluminio, con desenlace fatal, con el objetivo de asesorar e informar sobre los mecanismos de intoxicación y el manejo adecuado del paciente intoxicado.

Aluminium phosphide (AlP) is a fumigant pesticide inexpensive; whose only permitted use is for stored grain pest control. On contact with moisty air, it releases phosphine gas (PH3), highly toxic, flammable and explosive, but that quickly dissipates. For all presentations, a 3 g formulation generates 1 g of phosphine gas. Exposure to 1000 ppm for 30 minutes is lethal. We present a series of cases of severe poisoning with AlP, in order to advise and inform on the mechanisms of toxicity and proper management of the poisoned patient.

Aluminium Phosphide Poisoning.

Aluminium phosphide poisoning is a major cause of morbidity and mortality in northwest and central India. It liberates lethal phosphine gas when it comes in contact either with atmospheric moisture or with hydrochloric acid in the stomach. The mechanism of toxicity includes cellular hypoxia due to the effect on mitochondria, inhibition of cytochrome C oxidase and formation of highly reactive hydroxyl radicals. In India, most of the patients who come with Celphos poisoning succumb to its toxicity because of the considerable time gap between the ingestion of the poison and the initiation of proper treatment. This has led to widely prevalent scepticism among physicians while managing cases of Celphos poisoning. Due to no known specific antidote, management remains primarily supportive care. In most of the studies, poor prognostic factors were presence of acidosis and shock. The overall outcome improved in the last decade due to better and advanced intensive care management.

A Case of Aluminum Phosphide Poisoning

Aluminum phosphide is commonly used as a rodenticidal agent in agricultural workplaces. However, reported cases of aluminum phosphide poisoning in Korea are rare. Upon contact with moisture in the air, aluminum phosphide releases highly toxic phosphine gas (PH3). PH3 is readily absorbed through lung epithelium and into the bloodstream. Phosphine may cause denaturing of oxyhemoglobin and enzymes important to respiration and metabolism, and also may effect cellular membranes. There are numerous complications associated with acute aluminum phosphide poisoning including gastrointestinal, respiratory, and cardiac toxicities. We report the case of a 46-year-old man who suffered from respiratory and cardiac toxicities after unintentional aluminum phosphide exposure. More intensive education for prevention is recommended.

A simplified acute physiology score in the prediction of acute aluminum phosphide poisoning outcome.

Background : Aluminum phosphide (AlP) is used as a fumigant. It produces phosphine gas, which is a mitochondrial poison. Unfortunately, there is no known antidote for AlP intoxication, and also, there are few data about its prognostic factors. AIMS: The aim of this study was to determine the impact of the Simplified Acute Physiology Score II (SAPS II ) in the prediction of outcome in patients with acute AlP poisoning requiring admission to the Intensive Care Unit (ICU). Materials and Methods : This was a prospective study in patients with acute AlP poisoning, admitted to the ICU over a period of 12 months. The demographic data were collected and SAPSII was recorded. The patients were divided into survival and non-survival groups due to outcome. Statistical Analysis : The data were expressed as mean ± SD for continuous or discrete variables and as frequency and percentage for categorical variables. The results were compared between the two groups using SPSS software. Results : During the study period, 39 subjects were admitted to the ICU with acute AlP poisoning. All 39 patients required endotracheal intubation and mechanical ventilation in addition to gastric decontamination with sodium bicarbonate, permanganate potassium, and activated charcoal, therapy with MgSO 4 and calcium gluconate and adequate hydration. Among these patients, 26 (66.7%) died. SAPSII was significantly higher in the non-survival group than in the survival group (11.88 ± 4.22 vs. 4.31 ± 2.06, respectively) (P < 0.001). Conclusion : SAPSII calculated within the first 24 hours was recognized as a good prognostic indicator among patients with acute AlP poisoning requiring ICU admission.

Aluminium phosphide poisoning: management and prevention.

Death by Aluminium phosphide (AIP) and organo-phosphide poisoning are the commonest forms of poisoning in India. Aluminium phosphide is used as rodenticide and pesticide in grain storage facilities. It produces phosphine gas, which results in mitochondrial poisoning. There is no known antidote for AIP poisoning. The effects of AIP poisoning, mediated by phosphine and mechanism of action have not been established.The information related to this poisoning is available in the literature and substantiated by practical experience. Liberated phosphine cannot be detoxified but Magnesium sulphate has been reported to be effective. Another remedy can be rapid absorption by coconut oil which might be helpful. Treatment consists of gastric lavage with potassium permanganate solution, oral administration of charcoal and sorbitol suspension, intravenous administration of sodium bicarbonate, magnesium sulphate and calcium gluconate, and oral administration of sodium bicarbonate and coconut oil. Use of coconut oil for treatment in this poisoning is suggested, although clinical trials and scientific approval is still awaited. Every suggestion, news regarding new modality of treatment for this poisoning needs to be shared in the interest of saving precious human lives. It is with this aim the present paper is written.

A Clinical Study of Aluminium Phosphide Poisoning

The present prospective study 01'56 cases of Aluminium Phosphide (ALP) poisoning in Govt. Medical Collage Hospital Jammu, found out the prevalence of Deliberate self-poisoning self (DSP and accidental ingestion in young population in age group of 16-30 years. Male-female ratio was 1.03: 1.00; having marital discord and family quarrels as prominent predisposing factors. The majority of patients had gastrointestinal (GIT) symptoms (73.2%), cardiac arrthymias (62.5%) and shock (53.3%). The commonest clectrocardiographic (ECG) abnormalities were tachycardia (96%), atrial fibrillation (58%) and venticular-ectopic (VE) beats (59%). The management was supportive in the form of stomach wash, intraravenous (I/V) fluids, dopamine, hydrocortisone, sodabicarbonate and assisted ventilation in intensive care unit (lCU) setting and mortality rate was 75%. The fatal dose was 300 to 600 mg and fatal period as 2 to 16 hours.

Determinação de resíduos de fosfina em alimentos / Determination of phosphin residues in foods

Fosfina é um fumigante que está sendo usado em nosso país em larga escala. Como é tóxico a bem baixas concentrações, é necessário que se controlem os alimentos em que foi aplicado. Quarenta e cinco amostras de alimentos variados foram analisadas pelo método espectrofotométrico, sendo que em 77,8% destas foram encontrados resíduos. Os níveis variaram entre um máximo de 5,50 mg /kg e um mínimo de 0,01 mgv'kg (AU).