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Fab antivenom (FabAV) halts progression of tissue injury and improves recovery in copperhead snakebite. It is unknown if F(ab')2AV does as well. The objective of this study was to compare control of tissue injury in copperhead snakebite patients treated with F(ab')2AV versus FabAV. We performed a post hoc analysis of copperhead envenomated patients in a clinical trial comparing F(ab')2AV to FabAV. The outcomes for this analysis are the number of repeat doses required to obtain initial control, the number of patients requiring unscheduled doses during maintenance, and the time from antivenom administration to initial control. Twenty-one (13 F(ab')2AV, 8 FabAV) were copperhead patients. Median age was 46 years with a male predominance. Baseline severity was similar. One (8%) F(ab')2AV and 2(25%) FabAV patients required repeat initial dosing, difference = 17%, (95%CI −18, 57%). One (8%) F(ab')2AV and 1(13%) FabAV patients required additional doses after maintenance, difference = 5%, (95%CI −27, 45%). Median time to initial control was 2.7 range (2.0, 9.3) hours and 3.5 range (2.0, 7.4) for F(ab')2AV and FabAV respectively, difference −0.8 h (95% CI −2.6, 0.9). This exploratory analysis suggests that the available measures of the control of venom-induced tissue injury are similar between antivenom subgroups. [ABSTRACT FROM AUTHOR]

The article focuses on a case study of a potential envenomation attributed to a bite by a Western Fence Lizard. Topics include the nature of the symptoms, alternative explanations for the effects, and the need for comprehensive clinical documentation in similar cases to determine medical significance.

Abstract: Aluminium phosphide (AlP) is a toxic agent associated with a high mortality rate following acute exposure from various routes. The aim of this study was to determine the clinical and laboratory findings useful for predicting the medical outcome of AlP‐poisoned patients using established scoring systems. This is a prospective study of AlP‐poisoned patients from 2010 to 2015 in Ardabil, Iran. All patients that presented with a confirmed diagnosis of acute AlP poisoning in the study interval were included in the study. Clinical and laboratory data, using Acute Physiology and Chronic Health Evaluation II (APACHE II), Sequential Organ Failure Assessment (SOFA) and Simplified Acute Physiology Score II (SAPS II) scoring systems, were compared for their predictive value in determining differences between survived and non‐survived patients. Univariate analysis (Mann–Whitney or t‐test), multiple logistic regression analysis, receiver operating characteristic (ROC) curve analysis and the Pearson correlation test were performed using STATA/SE 13.0 and the Nomolog Software. A total of 68 AlP‐poisoned patients with confirmed acute AlP poisoning were included for evaluation. Of these, 36 were non‐survived. Multiple logistic regression analysis was performed using parameters and values derived from patient clinical and laboratory data, and revealed that four factors were significant for predicting mortality: Glasgow coma score (GCS); systolic blood pressure (SBP); urinary output (UOP); and serum HCO3. A four‐variable, risk‐prediction nomogram was developed for identifying high‐risk patients and predicting the risk of mortality. Study results showed that SBP of <92.5 mmHg (p = 0.006); HCO3‐ < 12.9 mEq/L (p = 0.01), UOP < 1725 mL/day (p = 0.04); and GCS < 14.5 (p = 0.003) were significant predictors of AlP mortality. Scoring systems analysis showed SAPS II score >24.5, APACHE II score >8.5 and SOFA score >7.5 were predictive of non‐survival patients. The results of our study showed that SBP, GCS, UOP and serum HCO3 levels are the best prognostic factors for predicting mortality in AlP‐poisoned patients. According to the area under the ROC curve of the APACHE II score, when compared with SOFA and SAPS II scores, the APACHE II score can more effectively discriminate between non‐survivors and survived patients. [ABSTRACT FROM AUTHOR]

The article discusses research on the specie, "Crotalus Pyrrhus (Southwestern Speckled Rattlesnake)" and explores about its geographical distribution and collection of specimen, along with explores diet of the species.

We previously showed different effects of tobacco and nicotine on fracture healing, but due to pump reservoir limits, maximum exposure period was 4 weeks. To allow flexibility in pre- and post-fracture exposure periods, the objective of this study was to compare a new oral administration route for nicotine to the established pump method. Four groups were studied: (1) pump saline, (2) pump saline + oral tobacco, (3) pump saline/nicotine + oral tobacco, and (4) pump saline + oral nicotine/tobacco. Sprague-Dawley rats (n = 84) received a transverse femoral fracture stabilized with an intramedullary pin 1 week after initiating dosing. After 3 weeks, no difference was found in torsional strength or stiffness between oral nicotine/tobacco or pump nicotine + tobacco, while energy absorption with oral nicotine/tobacco was greater than pump nicotine + tobacco ( p < 0.05). Compared to saline control, strength for oral nicotine/tobacco was higher than control ( p < 0.05), and stiffnesses for pump nicotine + tobacco and oral nicotine/tobacco were higher than control ( p < 0.05). No differences in energy were found for either nicotine-tobacco group compared to saline control. Mean serum cotinine (stable nicotine metabolite) was different between pump and oral nicotine at 1 and 4 weeks, but all groups were in the range of 1-2 pack/day smokers. In summary, relevant serum cotinine levels can be reached in rats with oral nicotine, and, in the presence of tobacco, nicotine can influence mechanical aspects of fracture healing, dependent on administration method. Caution should be exercised when comparing results of fracture healing studies using different methods of nicotine administration. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1235-1239, 2010 [ABSTRACT FROM AUTHOR]

Introduction:Protobothrops mangshanensis, the Mangshan pit viper, is a rare pit viper native to the area surrounding Mount Mang in China’s Hunan province. Toxicity from envenomation is not well characterized.Case details: A 33-year-old male presented to an emergency department (ED) after being bitten on the forearm by hisP. mangshanensis. He complained of mild swelling and pain at the bite site. He was admitted for observation and toxicology consultation. Following initially normal coagulation studies including platelets, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and D-dimer, fibrinogen decreased to 121 mg/dL and D-dimer concurrently rose to 377 ng/mL over 24 h. On hospital day 2 fibrinogen stabilized at 109 mg/dL and he was discharged with outpatient laboratory monitoring. Three days later, he returned with bruising to the contralateral arm. Fibrinogen was undetectable (<40 mg/dL) and PT was 14.6 s. He declined admission but returned 2 d later with bruising to the nose. Bloodwork revealed immeasurably prolonged PT, aPTT, and thrombin time, but he eloped. Late that evening he returned and was treated with three vials of Green pit viper (Trimeresurus albolabris) antivenom. Within 24 h coagulopathy improved markedly; at five days, coagulation abnormalities resolved.Discussion: Mangshan pit viper envenomations may cause isolated hemotoxicity, despite molecular studies suggesting additional neurotoxicity and myotoxicity.T. albolabrisantivenom appears effective in treating the resultant coagulopathy.Conclusion: We report the natural history of envenomation by the Mangshan pit viper. A delayed coagulopathy, apparently fibrinolytic in nature, is unaccompanied by local tissue destruction and responsive to Green pit viper antivenom. [ABSTRACT FROM AUTHOR]

Because of the adverse effects of smoking during pregnancy, understanding the factors that influence maternal smoking may help in developing better treatments to help women quit smoking during pregnancy. Animal models could be useful for this purpose. The purpose of the present study was to begin the development of an animal model of smoking during pregnancy by initially characterizing nicotine self-administration (NSA) in pregnant rats. Another purpose was to begin to explore the effects of pregnancy on nicotine pharmacokinetics in rats. In experiment 1, female rats self-administering nicotine during 23-h sessions were examined throughout gestation and lactation. In experiment 2, locomotor activity was measured during pregnancy to assess further potential motor effects of pregnancy. Experiments 3 and 4 compared the single-dose pharmacokinetics of nicotine in male, nonpregnant female, and pregnant females in the first and third trimester of pregnancy and the first week of lactation. NSA decreased over the course of pregnancy with NSA significantly lower in the third trimester compared to nonpregnant controls. NSA remained suppressed for up to 10 days into lactation. Locomotor behavior was also significantly suppressed during the second and third trimesters and throughout lactation. Nicotine elimination was slower in pregnant females compared to nonpregnant females only in the third trimester. NSA, locomotor behavior, and nicotine elimination in rats are decreased during late pregnancy. The present study is the first to characterize NSA during pregnancy in animals, providing a potential model of maternal smoking in humans. [ABSTRACT FROM AUTHOR]

We have previously shown that acetaldehyde, a constituent of tobacco smoke, increases nicotine self-administration in adolescent, but not adult, rats. The aim of this study was to determine whether acetaldehyde influences other behavioral, endocrine, or neuronal responses to nicotine at either age. Juvenile (postnatal day (P) 27) and adult (P90) male Sprague–Dawley rats were treated with saline, acetaldehyde (16 μg/kg/injection × 2, i.v.), nicotine (30 μg/kg/injection × 2, i.v.) or a combination of acetaldehyde and nicotine. Locomotion and center time were evaluated for 30 min in a novel open field, before measurement of plasma corticosterone levels and brain c-fos mRNA. Nicotine increased locomotor activity in juveniles but decreased it in adults; in contrast, center time was increased at both ages. Acetaldehyde potentiated nicotine's locomotor effects, but not center time. Nicotine induced c-fos expression in the bed nucleus of the stria terminalis, the central nucleus of the amygdala (CeA), nucleus accumbens, and the superior colliculus (SC) at both ages, whereas it activated the hypothalamic paraventricular nucleus (PVN) and consequent corticosterone secretion only in adults. Acetaldehyde potentiated nicotine-induced c-fos in CeA and SC, and activation of PVN c-fos expression/plasma corticosterone release; however, this drug interaction was only observed in behaviorally tested animals, not those that were minimally stressed. Thus, acetaldehyde may modulate the interaction of nicotine and stress. Although pharmacokinetic studies showed that acetaldehyde did not change nicotine levels in either brain or serum, nicotine penetration into the brain was slower in juveniles as compared to adults.Neuropsychopharmacology (2007) 32, 2025–2035; doi:10.1038/sj.npp.1301327; published online 7 February 2007 [ABSTRACT FROM AUTHOR]

The article discusses research on the physiological and behavioral effects of a nicotine conjugate vaccine on the acquisition and maintenance of nicotine self-administration in rats. It provides information on the methods and materials used in the study. It also discusses the results of the study.

A sensitive and reliable HPLC method that allows simultaneous quantification of phytoestrogens extracted from kudzu-root and soy preparations, and serum samples has been developed. Kudzu-root and soy preparations were mixed with 5 µg flavone and 15 µg rutin (internal standards) and the phytoestrogens were extracted by using solid-phase (C18) extraction cartridges. Blank or spiked serum samples were extracted by using either C18 cartridges or trichloroacetic acid-methanol extraction. The extracts were analyzed by the HPLC equipped with a reverse-phase (250 × 4 mm, C18) column and UV, diode-array or MS detector. A linear gradient of acetic acid and acetonitrile provided excellent separation of glycoside and aglycone-phytoestrogens from kudzu root and soy preparations. The C18 cartridge extraction of serum yielded excellent recovery of both glycoside- and aglycone-phytoestrogens, while the trichloroacetic acid-methanol extraction yielded excellent recovery of glycoside but poor recovery of aglycone compounds. UV and MS detectors were suitable for phytoestrogen analysis in plant and serum samples, while the diode-array detector was suitable for generating the UV absorbance curve for phytoestrogens. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Rationale. The efficacy of nicotine replacement therapy (NRT) for smoking cessation is limited. One reason for this limited efficacy may be that typical serum nicotine concentrations provided by NRT do not match the peak arterial nicotine concentrations achieved from smoking. Objective. The purpose of the present study was to determine whether continuous nicotine infusion at a rate producing serum nicotine concentrations that match the estimated peak arterial nicotine concentrations associated with nicotine self-administration (NSA) in rats produces greater suppression of NSA than lower infusion rates. Methods. The effects of continuous nicotine infusion were studied by intravenously administering nicotine at various rates (1.0, 3.0, and 8.0 mg/kg per day) to rats concurrently self-administering nicotine (0.03 mg/kg per infusion) during 23-h sessions or cocaine (0.17 mg/kg per infusion) during 2-h sessions. Results. Continuous nicotine infusion suppressed NSA in a rate-related fashion. NSA was suppressed by 17, 50, and 73% at infusion rates of 1.0, 3.0 and 8.0 mg/kg per day, respectively. The 8.0-mg/kg per day infusion rate, which provided venous serum nicotine concentrations equaling the peak arterial concentrations associated with NSA, suppressed NSA to a greater extent than lower infusion rates. The 8.0-mg/kg per day nicotine infusion rate had no effect on cocaine-maintained responding, demonstrating that its effects were specific for suppression of NSA. This infusion rate provided a mean percentage replacement of nicotine from NSA of more than 700%. Reacquisition of NSA after suppression by the two highest infusion rates was delayed compared with reacquisition after saline extinction. Conclusions. Continuous nicotine infusion produced an infusion rate-related suppression of NSA that was greatest when the infusion provided nicotine doses and venous serum concentrations substantially higher than those typically associated with NRT in humans. [ABSTRACT FROM AUTHOR]

Presents a study which investigated quality in ephedrine-containing dietary supplements. Experimental section; Results and discussion; Conclusion.

Active immunization of rats against nicotine reduces the distribution of a single intravenous dose of nicotine to brain. The current study examined the effects of immunization on the distribution of repeated doses of nicotine, and on estimates of nicotine pharmacokinetic parameters. Groups of rats received five repeated doses of nicotine over 80 min (total dose equivalent to the nicotine intake from one, three or 10 cigarettes in a human). The serum nicotine concentration in immunized rats was 160-430% higher than controls after the fifth dose, demonstrating binding of nicotine to antibody. Brain nicotine concentration in immunized rats was reduced by 30-46%. The reduction in distribution of nicotine to brain correlated with the serum hapten-specific antibody concentration, the percentage of nicotine bound in serum, and with the unbound nicotine concentration in serum. In immunized rats, nicotine had a smaller steady state volume of distribution, lower systemic clearance, and longer terminal half-life than in controls. These data demonstrate that immunization against nicotine reduces nicotine distribution to brain, even after multiple nicotine doses at rates approximating heavy cigarette smoking. Whether this reduction in nicotine distribution is large enough to alter nicotine's physiological or behavioral effects remains to be studied. [ABSTRACT FROM AUTHOR]

Addresses the potential role of calcium channel blockade in tricyclic antidepressant-induced hypotension. Inhibition of calcium influx by calcium channel blocking drugs such as verapamil or nifedipine which can contribute to the hypotension; Potential importance of calcium channel blocker as a contributor to tricyclic antidepressant (TCA) toxicity.

Rapid Administration of High-Dose Human Antibody Fab Fragments to Dogs: Pharmacokinetics and Toxicity. Keyler, D. E., Salerno, D. M., Murakami, M. M., Ruth, G., and Pentel, P. R. (1991). Fundam. Appl Toxicol 17, 83-91. The treatment of drug overdose with drug-specific antibody fragments may require very high antibody doses. To address the feasibility of this therapy, we studied the pharmacokinetics and toxicity of high-dose human nonspecific Fab fragments in beagles. Three dogs received 5.3 g/kg Fab iv over 1 hr. Because nephrotoxicity was observed, three subsequent dogs received 3.2 g/kg. The fraction of the Fab dose excreted in urine (10 ± 6%%) was lower than reported values for either high or low doses of Fab in other species. The terminal serum elimination half-life (42 hr for the higher and 48 hr for the lower dose) was also longer than reported values for other species, due to lower renal and nonrenal Fab clearance. Fab administration was tolerated without adverse hemodynamic effects. One of three dogs at each dose developed transient oliguria. All dogs developed a transient but marked increase in the serum creatinine concentration. At 2 weeks creatinine clearance had returned to normal. Urinary protein and albumin excretion at 2 weeks were within the normal range for dogs but were increased over their baseline values. The histology of all organs was normal at 3 weeks by light microscopy, and renal histology by electron microscopy was also normal. The mechanism of Fab nephrotoxicity, not observed previously with high-dose Fab in rats or lower doses of Fab in other species including dogs, is not clear. These data suggest that further study of the potential toxicity of high-dose Fab, and its reversibility, is needed to assess the feasibility of treating drug overdose with this antibody fragment The long terminal half-life of high-dose Fab in the dog and its low renal clearance contrast with values observed with lower doses of Fab in other species but would not be expected to preclude the use of high-dose Fab for drug overdose. [ABSTRACT FROM PUBLISHER]