Lung Examination in Systemic Toxicitytest of Medical Devices / 中国医疗器械杂志

The lung is an important organ in systemic toxicity test of medical devices and is significant in safety evaluation. Based on the authors' understanding of medical devices, this study provides a brief analysis of the lung examination and common problems in systemic toxicity, so as to provide references for the pre-clinical safety evaluation of medical devices. It should be noted that a reasonable risk assessment should be made after comprehensive assessment for specific medical device products.

Troubleshooting for epileptiform activity during percutaneous transvenous mitral commisurotomy

Percutaneous transvenous mitral commisurotomy (PTMC) is a frequently used minimally invasive procedure for patients with symptomatic mitral stenosis. However, it is not without complications. Few complications which are distinctive to the procedure are thromboembolism, left-to-right shunts, mitral regurgitation, cardiac tamponade and complete heart block. We present the case of a 32-year-old female patient scheduled for a PTMC, who had multiple complications during the procedure. She developed cardiac tamponade for which pericardiocentesis and autotransfusion was done. Subsequently she exhibited epileptiform activity for which there was a diagnostic dilemma due to the presence of multiple confounding factors. However, she had a complete recovery without any residual sequelae at the time of discharge.

Lipid emulsion therapy of local anesthetic systemic toxicity due to dental anesthesia

Local anesthetic systemic toxicity (LAST) refers to the complication affecting the central nervous system (CNS) and cardiovascular system (CVS) due to the overdose of local anesthesia. Its reported prevalence is 0.27/1000, and the representative symptoms range from dizziness to unconsciousness in the CNS and from arrhythmias to cardiac arrest in the CVS. Predisposing factors of LAST include extremes of age, pregnancy, renal disease, cardiac disease, hepatic dysfunction, and drug-associated factors. To prevent the LAST, it is necessary to recognize the risk factors for each patient, choose a safe drug and dose of local anesthesia, use vasoconstrictor , confirm aspiration and use incremental injection techniques. According to the treatment guidelines for LAST, immediate application of lipid emulsion plays an important role. Although lipid emulsion is commonly used for parenteral nutrition, it has recently been widely used as a non-specific antidote for various types of drug toxicity, such as LAST treatment. According to the recently published guidelines, 20% lipid emulsion is to be intravenously injected at 1.5 mL/kg. After bolus injection, 15 mL/kg/h of lipid emulsion is to be continuously injected for LAST. However, caution must be observed for >1000 mL of injection, which is the maximum dose. We reviewed the incidence, mechanism, prevention, and treatment guidelines, and a serious complication of LAST occurring due to dental anesthesia. Furthermore, we introduced lipid emulsion that has recently been in the spotlight as the therapeutic strategy for LAST.

Hypersensitivity Reaction to Perioperative Drug Mistaken for Local Anesthetic Systemic Toxicity in a Patient under Brachial Plexus Block / 고신대학교의과대학학술지

Perioperative anaphylaxis, although rare, is a severe, life-threatening unexpected systemic hypersensitivity reaction. Simultaneous administration of various drugs during anesthesia, the difficulty of communicate with patients in sedation and anesthesia, and coverage of the patient with surgical drapes are considered to be factors that impede early recognition of anaphylactic reactions. It is very important to perform an intradermal skin test because antibiotics are the most common cause of perioperative anaphylaxis. We report a case of negative-intradermal skin test antibiotic anaphylaxis mistaken for local aesthetic systemic toxicity without increase of serum tryptase for confirmative diagnostic biomaker during surgery under brachial plexus block. It is not possible to exclude the danger of anaphylaxis completely, even if it is negative-intradermal skin test and normal tryptase level. Therefore, anesthesiologists should be closely monitored and treated early for antibiotics related hypersensitive reaction, like other medicines during anesthesia.

Humidifier disinfectants, unfinished stories

Once released into the air, humidifier disinfectants became tiny nano-size particles, and resulted in chemical bronchoalveolitis. Families had lost their most beloved members, and even some of them became broken. Based on an estimate of two million potential victims who had experienced adverse effects from the use of humidifier disinfectants, we can say that what we have observed was only the tip of the iceberg. Problems of entire airways, as well as other systemic effects, should be examined, as we know these nano-size particles can irritate cell membranes and migrate into systemic circulation. The story of humidifier disinfectant is not finished yet.

An analysis of a humidifier disinfectant case from a toxicological perspective

An analysis of patients and fatalities due to exposure to polyhexamethylene guanidine (PHMG) shows that PHMG causes mainly lung diseases such as pulmonary fibrosis. However, no research on the other organs has been conducted on this matter yet. So, an in-depth discussion on toxicological techniques is needed to determine whether or not PHMG is toxic to organs other than just the lungs. For the test of target organ toxicity by PHMG exposure, a toxicokinetic study must first be conducted. However, measurement method for PHMG injected into the body has not yet been established because it is not easy to analyze polymer PHMG, so related base studies on analytical technique for PHMG including radio-labeling chemistry must come first. Moreover, research on exposure-biomarker and effect-biomarker must also be conducted, primarily related to clinical application. Several limitations seem to be expected to apply the biomarker study to the patient because much time has passed after exposure to the humidifier disinfectant. It is why a more comprehensive toxicological researches must be introduced to the causality for the victims.

Cytolytic and systemic toxic effects induced by the aqueous extract of the fire coral Millepora alcicornis collected in the Mexican Caribbean and detection of two types of cytolisins

Background Millepora alcicornis is a branching hydrocoral common throughout the Caribbean Sea. Like other members of this genus, this species is capable of inducing skin eruptions and blisters with severe pain after contact. In the present study, we investigated the toxicity of theM. alcicornis aqueous extract on several animal models. Considering that some cnidarian hemolysins have been associated to local tissue damage, since they also induce lysis of other cell types, we also made a partial characterization of the hemolytic activity of M. alcicornis aqueous extract. This information is important for understanding the defense mechanisms of the fire corals.Methods The effects of pH, temperature, and some divalent cations on the hemolytic activity of the extract were assayed, followed by a zymogram analysis to detect the cytolysins and determine their approximate molecular weight. The toxicity of the aqueous extract was assayed in mice, by intravenous administration, and histopathological changes on several tissues were analyzed by light microscopy. The toxicity of the extract was also tested inArtemia salina nauplii, and the damages caused on the crustaceans were analyzed by transmission and scanning electron microscopy.Results The hemolytic activity of the hydrocoral extract was enhanced in the presence of Ca 2+ (2 mM), Mg 2+ (6 mM), and Ba2+ (0.1 mM); however, it was reduced in the presence of Cu2+(0.1 mM), Zn 2+ (6 mM), and EDTA (0.34 mM). Differences in the pH did not affect the hemolytic activity, but it was temperature-sensitive, since preincubation at 50 °C sharply reduced hemolysis. The zymogram showed the presence of two types of hemolysins: ~ 2830 kDa proteins with phospholipase A 2 activity and ~ 200 kDa proteins that do not elicit enzymatic activity. The aqueous extract of this cnidarian was lethal to mice (LD 50 = 17 g protein/g), and induced kidney, liver, and lung damages. Under denaturing conditions, the aqueous extract completely lost its toxic and hemolytic activities.Conclusions The results showed that the M. alcicornis aqueous extract contains two types of thermolabile hemolysins: proteins of approximately 2830 kDa with PLA 2 activity, while the others are larger proteins of approximately 200 kDa, which do not possess PLA 2activity. Those thermolabile cytolysins, which are stable to pH changes and whose activity is calcium dependent, are capable of inducing damage in lung, kidney and liver tissues, resulting in a slow death of mice. M. alcicorniscytolysins also provoke tissue dissociation inArtemia salina nauplii that might be attributed to pore forming mechanisms.

Cytolytic and systemic toxic effects induced by the aqueous extract of the fire coral Millepora alcicornis collected in the Mexican Caribbean and detection of two types of cytolisins

Background Millepora alcicornis is a branching hydrocoral common throughout the Caribbean Sea. Like other members of this genus, this species is capable of inducing skin eruptions and blisters with severe pain after contact. In the present study, we investigated the toxicity of theM. alcicornis aqueous extract on several animal models. Considering that some cnidarian hemolysins have been associated to local tissue damage, since they also induce lysis of other cell types, we also made a partial characterization of the hemolytic activity of M. alcicornis aqueous extract. This information is important for understanding the defense mechanisms of the "fire corals".Methods The effects of pH, temperature, and some divalent cations on the hemolytic activity of the extract were assayed, followed by a zymogram analysis to detect the cytolysins and determine their approximate molecular weight. The toxicity of the aqueous extract was assayed in mice, by intravenous administration, and histopathological changes on several tissues were analyzed by light microscopy. The toxicity of the extract was also tested inArtemia salina nauplii, and the damages caused on the crustaceans were analyzed by transmission and scanning electron microscopy.Results The hemolytic activity of the hydrocoral extract was enhanced in the presence of Ca 2+ (≥2 mM), Mg 2+ (≥6 mM), and Ba2+ (≥0.1 mM); however, it was reduced in the presence of Cu2+(≥0.1 mM), Zn 2+ (≥6 mM), and EDTA (≥0.34 mM). Differences in the pH did not affect the hemolytic activity, but it was temperature-sensitive, since preincubation at ≥ 50 °C sharply reduced hemolysis. The zymogram showed the presence of two types of hemolysins: ~ 28-30 kDa proteins with phospholipase A 2 activity and ~ 200 kDa proteins that do not elicit enzymatic activity. The aqueous extract of this cnidarian was lethal to mice (LD 50 = 17 μg protein/g), and induced kidney, liver, and lung damages. Under denaturing conditions, the aqueous extract completely lost its toxic and hemolytic activities.Conclusions The results showed that the M. alcicornis aqueous extract contains two types of thermolabile hemolysins: proteins of approximately 28-30 kDa with PLA 2 activity, while the others are larger proteins of approximately 200 kDa, which do not possess PLA 2activity. Those thermolabile cytolysins, which are stable to pH changes and whose activity is calcium dependent, are capable of inducing damage in lung, kidney and liver tissues, resulting in a slow death of mice. M. alcicorniscytolysins also provoke tissue dissociation inArtemia salina nauplii that might be attributed to pore forming mechanisms.(AU)

Necrotizing fasciitis of the head and neck: a case report

Necrotizing fasciitis (NF) is an infection that spreads along the fascial planes, causing subcutaneous tissue death characterized by rapid progression, systemic toxicity, and even death. NF often appears as a red, hot, painful, and swollen wound with an ill-defined border. As the infective process continues, local pain is replaced by numbness or analgesia. As the disease process continues, the skin initially becomes pale, then mottled and purple, and finally, gangrenous. The ability of NF to move rapidly along fascial planes and cause tissue necrosis is secondary to its polymicrobial composition and the synergistic effect of the enzymes produced by the bacteria. Treatment involves securing the airway, broad-spectrum antimicrobial therapy, intensive care support, and prompt surgical debridement, repeated as needed. Reducing mortality rests on early diagnosis and prompt aggressive treatment.

Systemic and reproductive toxicity induced by Parkia platycephala ethanolic extract in female Wistar rats

The present study was conducted to evaluate the toxicity of the ethanolic extract of leaves of Parkia platycephala Benth., Fabaceae, on systemic and reproductive parameters. In toxicity on the estrous cycle, four groups of not-pregnant Wistar rats received distilled water and the doses 250, 500 and 1000 mg.kg-1 of plant extract for thirty days, at the end of which they were examined as to the frequency of their phases. The systemic toxicity was assessed through the consumption of water and food and by measuring body mass. After the extract was administered, serum AST, ALT, ALP, bilirubin (total, direct and indirect), urea and creatinine were dosed. The evaluation of the organs (brain, heart, hypophysis, adrenal glands, liver, spleen, uterus and ovaries) in their macroscopic aspects, relative and absolute masses and histological structure showed that the plant extract induced a decrease of water and food consumption and of body mass. It caused an increase in the luteal phase and a decrease in the follicular phase of the estrous cycle and rose serum alkaline phosphatase levels.The data exhibit systemic and reproductive toxicity induced by plant extract in female Wistar rats.

Systemic toxicity of (S)-(-)-pantoprazole sodium in rats following intravenous injection for 30 d / 中国药学杂志

OBJECTIVE: The systemic toxicities of S-(-)-pantoprazole sodium in rats following intravenous injuction for 30 d were studied. METHODS: One hundred rats were divided randomly into 5 groups: vehicle control group, pantoprazole sodium control group and three S-(-)-pantoprazole sodium groups with different dosages, and received vehicle, pantoprazole sodium(80 mg·kg-1·d-1), S-(-)-pantoprazole sodium(80, 40 and 20 mg·kg-1·d-1) by i.v.via tail vein. Administrations were performed each day for consecutive 30 d. Haematological parameters, biochemical parameters, and histopathology analysis were determined at 30 d of treatments and 14 d after the withdrawal, respectively. RESULTS: The rats in the S-(-)-pantoprazole sodium group at 80 mg·kg-1·d-1 apperanced shortness of breath, unsteady gait, lying motionless and other symptoms. The levels of TC, Na+, Cl- in this group were significantly higher or lower than those in vehicle control group at 30 d(P<0.05), The change of these parameters regained to normal at 14 d after withdrawal. CONCLUSION: Intravenous administration of the S-(-)-pantoprazole sodium for 30 d at high dose could induce reversible damage to liver and electrolyte. The toxicity of S-(-)-pantoprazole sodium is similar with pantoprazole sodium at the same dosage.

Lipid emulsion-mediated reversal of toxic-dose aminoamide local anesthetic-induced vasodilation in isolated rat aorta / 대한마취과학회지

BACKGROUND: Intravenous lipid emulsion has been used to treat systemic toxicity of local anesthetics. The goals of this in vitro study were to determine the ability of two lipid emulsions (Intralipid(R) and Lipofundin(R) MCT/LCT) to reverse toxic dose local anesthetic-induced vasodilation in isolated rat aortas. METHODS: Isolated endothelium-denuded aortas were suspended for isometric tension recording. Vasodilation was induced by bupivacaine (3 x 10(-4) M), ropivacaine (10(-3) M), lidocaine (3 x 10(-3) M), or mepivacaine (7 x 10(-3) M) after precontraction with 60 mM KCl. Intralipid(R) and Lipofundin(R) MCT/LCT were then added to generate concentration-response curves. We also assessed vasoconstriction induced by 60 mM KCl, 60 mM KCl with 3 x 10(-4) M bupivacaine, and 60 mM KCl with 3 x 10(-4) M bupivacaine plus 1.39% lipid emulsion (Intralipid(R) or Lipofundin(R) MCT/LCT). RESULTS: The two lipid emulsions reversed vasodilation induced by bupivacaine, ropivacaine, and lidocaine but had no effect on vasodilation induced by mepivacaine. Lipofundin(R) MCT/LCT was more effective than Intralipid(R) in reversing bupivacaine-induced vasodilation. The magnitude of lipid emulsion-mediated reversal of vasodilation induced by high-dose local anesthetics was as follows (from highest to lowest): 3 x 10(-4) M bupivacaine-induced vasodilation, 10(-3) M ropivacaine-induced vasodilation, and 3 x 10(-3) M lidocaine-induced vasodilation. CONCLUSIONS: Lipofundin(R) MCT/LCT-mediated reversal of bupivacaine-induced vasodilation was greater than that of Intralipid(R); however, the two lipid emulsions equally reversed vasodilation induced by ropivacaine and lidocaine. The magnitude of lipid emulsion-mediated reversal of vasodilation appears to be correlated with the lipid solubility of the local anesthetic.

Lipid Emulsions Enhance the Norepinephrine-Mediated Reversal of Local Anesthetic-Induced Vasodilation at Toxic Doses

PURPOSE: Intravenous lipid emulsions have been used to treat the systemic toxicity of local anesthetics. The goal of this in vitro study was to examine the effects of lipid emulsions on the norepinephrine-mediated reversal of vasodilation induced by high doses of levobupivacaine, ropivacaine, and mepivacaine in isolated endothelium-denuded rat aorta, and to determine whether such effects are associated with the lipid solubility of local anesthetics. MATERIALS AND METHODS: The effects of lipid emulsions (0.30, 0.49, 1.40, and 2.61%) on norepinephrine concentration-responses in high-dose local anesthetic (6x10-4 M levobupivacaine, 2x10-3 M ropivacaine, and 7x10-3 M mepivacaine)-induced vasodilation of isolated aorta precontracted with 60 mM KCl were assessed. The effects of lipid emulsions on local anesthetic- and diltiazem-induced vasodilation in isolated aorta precontracted with phenylephrine were also assessed. RESULTS: Lipid emulsions (0.30%) enhanced norepinephrine-induced contraction in levobupivacaine-induced vasodilation, whereas 1.40 and 2.61% lipid emulsions enhanced norepinephrine-induced contraction in both ropivacaine- and mepivacaine-induced vasodilation, respectively. Lipid emulsions (0.20, 0.49 and 1.40%) inhibited vasodilation induced by levobupivacaine and ropivacaine, whereas 1.40 and 2.61% lipid emulsions slightly attenuated mepivacaine (3x10-3 M)-induced vasodilation. In addition, lipid emulsions attenuated diltiazem-induced vasodilation. Lipid emulsions enhanced norepinephrine-induced contraction in endothelium-denuded aorta without pretreatment with local anesthetics. CONCLUSION: Taken together, these results suggest that lipid emulsions enhance the norepinephrine-mediated reversal of local anesthetic-induced vasodilation at toxic anesthetic doses and inhibit local anesthetic-induced vasodilation in a manner correlated with the lipid solubility of a particular local anesthetic.

Late onset of systemic toxicity of local anesthetics in brachial plexus block: A case report

Early onset of systemic toxicity of local anesthetics is a common complication in regional anesthesia. However late onset of systemic toxicity is an unfamiliar phenomenon for an anesthesiologist. We present a case of a late onset of systemic toxicity of local anesthestics in a patient who received brachial plexus block for hand surgery. An hour later after the block, he complained of light-headedness and anxiety. Then he was found to be unconsciousness with involuntary movement of his four extremities. Later his speech became slurred and patient became unresponsive. Following which, general anesthesia was induced and the patient recovered his consciousness after surgery with no sequela related to systemic toxicity with local anesthetics. We observe from this report that considering the time for local anesthetics to reach peak plasma concentration, anesthesiologists should monitor and observe their patient for at least an hour from the completion of brachial plexus block.

Preparation and Pegylation of TNF-? Derivative / 中国生物工程杂志

The gene of mutated TNF-?D4 gene was amplified by overlap PCR and cloned into the prokaryotic expressive vector pBV220.TNF-?D4 contains two changes:substitutions of Pro8Arg,Ser9Lys,Asp10Arg,Ile157Phe,Leu29Ser,Arg31Val and a deletion of the N terminal four amino acids.The recombinant vector pBV220-TNF-?D4 was transformated into E.coli strain DH5?,and the high expression strain was obtained by screening monoclones.The level of expression was about 45% of total cell protein.After purification,the purity of fusion protein was above 90% by HPLC and relative ability was 8 ?107.TNF-?D4 was modificated by mPEG-ButyrALD。After purification,the purity of mPEG-TNF-?D4 was above 85% and relative ability was 8.6?107.The in vivo systemic toxicity of mPEG-TNF-?D4,which is indicated by LD50,is lower than that of rhTNF-?.These results strongly supported for the further study and exploitation of TNF-antitumor drug.

Pulmonary Aspiration and Local Anesthetic Systemic Toxicity following Epidural Anesthesia / 대한마취과학회지

Aspiration can generate postoperative pulmonary morbidity of varing severity, depending on the type and volume of the aspirate. Epidural anesthesia can lead to local anesthetic systemic toxicity with mental change, followed by respiratory depression and abdominal and intercostal muscle weakness depressing the ability of the patient to cough and clear the airway. The authors experienced a case of pulmonary aspiration with systemic toxicity after epidural anesthesia for cesarean section. The chest X-ray showed alveolar consolidation at left lower lung field and arterial blood gases showed that PaO2 decreased. The exact causes of mental change and respiratory depression were unknown, but we suspected it lidocaine induced systemic toxicity due to vascular absorption, When airway reflexes are ineffective during face mask ventilation of the lungs, aspiration of clear oral secretions can generate small airway obstruction.