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INTRODUCTION: Alcohol withdrawal syndrome (AWS) is a serious consequence of alcohol use disorder (AUD). Due to the current COVID-19 pandemic there was a closure of Pennsylvania (PA) liquor stores on March 17, 2020. METHODS: This is a retrospective, observational study of AWS patients presenting to a tertiary care hospital. We used descriptive statistics for continuous and categorical variables and compared AWS consults placed to the medical toxicology service for six months preceding liquor store closure to those placed between March 17, 2020 and August 31, 2020. We compared this to consults placed to the medical toxicology service placed from October 1, 2019 through March 16, 2020. Charts were identified based on consults placed to the medical toxicology service, and alcohol withdrawal was determined via chart review by a medical toxicologist. This study did not require IRB approval. We evaluated Emergency Department (ED) length of stay (LOS), weekly and monthly consultation rate, rate of admission and ED recidivism, both pre- and post-liquor store closure. RESULTS: A total of 324 AWS consults were placed during the ten month period. 142 (43.8%) and 182 (56.2%) consults were pre- and post-liquor store closure. The number of consults was not statistically significant comparing these two time frames. There was no significant difference by patient age, gender, or race or by weekly or monthly consultation rate when comparing pre- and post-liquor store periods. The median ED LOS was 7 h (95% Confidence Interval (CI) Larson et al. (2012), Pollard et al. (2020) [5, 11]) and did not significantly differ between pre- and post-liquor store periods (p = 0.78). 92.9% of AWS patients required admission without significant difference between the pre- and post-liquor store closure periods (94.4% vs. 91.8%, p = 0.36). There was a significant increase in the number of AWS patients requiring a return ED visit (Odds Ratio 2.49; 95% CI [1.38, 4.49]) post closure. CONCLUSION: There were nearly 2.5 times greater odds of ED recidivism among post-liquor store closure AWS patients compared with pre-closure AWS patients.
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Bebidas Alcohólicas , Alcoholismo/epidemiología , COVID-19/prevención & control , Control de Enfermedades Transmisibles/organización & administración , Derivación y Consulta/estadística & datos numéricos , Síndrome de Abstinencia a Sustancias/epidemiología , Adulto , Alcoholismo/diagnóstico , Alcoholismo/terapia , COVID-19/epidemiología , COVID-19/transmisión , Servicio de Urgencia en Hospital/estadística & datos numéricos , Utilización de Instalaciones y Servicios , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Pennsylvania/epidemiología , Estudios Retrospectivos , Síndrome de Abstinencia a Sustancias/diagnóstico , Síndrome de Abstinencia a Sustancias/terapia , Adulto JovenRESUMEN
INTRODUCTION: The Toxicology Investigator's Consortium (ToxIC) maintains a prospective case registry of all patients that have been managed at the bedside by medical toxicologists. We set out to characterize the differences in toxicological suicide attempts between men and women among adult patients with poisonings managed by medical toxicologists. METHODS: ToxIC database consults for adults aged 19-65 whose primary reasons for encounter were classified as suicide attempt were used for this study (1/2010-12/2016). Data used for analysis included primary agents of toxic exposure, routes of administration, and complications. The statistical analysis was limited to descriptive methods. RESULTS: Out of 51,440 registry cases, 33,259 cases remained for analysis after applying the ages 19-65 and removing those without complete data. Of these, there were 4827 suicide attempts (14.5% of toxicological exposures) which were sub classified by gender. There were more females (F) than males (M) whose toxicology consults were due to suicidal attempts (57.6% versus 42.4%). We also found that more males used alcohol as their primary agent (2.8%M v 1.5%F) or a nonpharmaceutical (%7.4â¯M v %2.3 F). CONCLUSIONS: In our study, we found that there were more females than males who attempted suicide by self-poisoning; and more of them used pharmaceuticals than males. In contrast, a greater number of males used nonpharmaceuticals such as alcohol. We did not find large sex-differences in suicide completion rates, routes of administration, or subsequent symptomologies. In summary, sex-based differences were observed between adult patients with suicidal-intent exposures/ingestions managed at the bedside by medical toxicologists.
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Sobredosis de Droga/epidemiología , Etanol/envenenamiento , Factores Sexuales , Intento de Suicidio/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intoxicación/epidemiología , Embarazo , Estudios Prospectivos , Sistema de Registros , Ideación Suicida , Toxicología , Estados Unidos/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Loperamide is an over-the-counter, inexpensive, antidiarrheal opioid that can produce life-threatening toxicity at high concentrations. CASE REPORT 1: A 28-year-old man with a history of depression and substance abuse disorder (SUD) presented to the emergency department (ED) with shortness of breath and lightheadedness. He ingested large amounts of loperamide daily. The patient's initial electrocardiogram (ECG) demonstrated sinus rhythm, right axis deviation, undetectable PR interval, QRS 168 ms, and QTc 693 ms. He was administered intravenous sodium bicarbonate and magnesium sulfate and admitted to the intensive care unit, eventually developing Torsades de Pointes (TdP). He was given lidocaine and isoproterenol infusions, and an external pacemaker was placed. He was discharged in stable condition on hospital day (HD) 16. CASE REPORT 2: A 39-year-old woman with a history of hepatitis C, depression, and SUD was transported to the ED after reported seizure-like activity. The patient experienced TdP in the ED and admitted to ingesting large amount of loperamide daily. An ECG demonstrated sinus rhythm, right axis deviation, PR interval 208 ms, QRS interval 142 ms, and QTc 687 ms. She was administered intravenous magnesium, sodium bicarbonate, and isoproterenol. After intensive care unit admission, the patient experienced no further TdP and was discharged on HD 6. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should proceed with caution when treating patients with loperamide toxicity. Even in asymptomatic patients and drug discontinuance, obtain consultation with a medical toxicologist, promptly treat ECG abnormalities aggressively, and admit all patients for further monitoring.
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Antidiarreicos/envenenamiento , Sobredosis de Droga/complicaciones , Loperamida/envenenamiento , Torsades de Pointes/inducido químicamente , Adulto , Femenino , Humanos , MasculinoRESUMEN
Objectives: Phenobarbital (PB) is a long-acting GABA A-agonist with favorable pharmacokinetics (long half-life and duration of effect) that allows effective treatment of alcohol withdrawal (AW) after administration of a single loading dose. Current evidence suggests that in the setting of AW, PB administration may be associated with decreased hospital admissions and hospital length of stay. The aim of this study was to evaluate the safety outcomes of AW patients who were treated and discharged from the emergency department (ED) after receiving PB for AW. Methods: This retrospective chart review included a convenience sample of 33 AW patients who presented to four EDs within an 18-month span. Descriptive statistics (frequencies and percentages) were used to describe demographics, distribution of resources and referrals, and the safety outcomes of PB administration for low-risk AW patients. Patients were selected for inclusion in consultation with a medical toxicologist, treated with PB, and discharged from the ED. Electronic medical records were utilized to gather information on the patient cohort. Results: All patients were treated with at least a single loading dose of 5â10 mg/kg (ideal body weight) of intravenous or per os PB during their ED stay. Only one patient had an unanticipated event after discharge, which was related to driving against advice. Two additional patients had ED revisits for recurrent alcohol use within 72 h, and 16 patients had recurrent alcohol use within 30 days. All 33 patients were provided with resources for linkage to treatment. None required hospital admission. Conclusion: ED PB "load and go" may be a safe, effective AW treatment that could help treat AW, facilitate linkage to specific rehabilitation treatments, and decrease hospital admissions.
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Intake of anthocyanin-rich New Zealand blackcurrant (NZBC) can alter physiological responses that enhance exercise performance. In two studies, we examined the effects of NZBC extract on force steadiness during a sustained submaximal isometric contraction of the quadriceps femoris muscle. With repeated measures designs, male participants in study one (n = 13) and study two (n = 19) performed a 120 s submaximal (30%) isometric contraction of the quadriceps femoris muscle following a 7-day intake of NZBC extract and placebo (study one) and following 0 (control), 1-, 4- and 7-day intake of NZBC extract (study two). Participants for both studies were different. In study one, NZBC extract enhanced isometric force steadiness during the 120 s contraction (placebo: 6.58 ± 2.24%, NZBC extract: 6.05 ± 2.24%, p = 0.003), with differences in the third (60-89 s) and fourth quartile (90-120 s) of the contraction. In study two, isometric force steadiness was not changed following 1 and 4 days but was enhanced following 7-day intake of NZBC extract in comparison to control. In study two, the enhanced isometric force steadiness following 7-day intake did occur in the second (30-59 s), third (60-89 s) and fourth (90-120 s) quartiles. Daily supplementation of anthocyanin-rich NZBC extract can enhance force steadiness of the quadriceps femoris muscle during a sustained submaximal isometric contraction. Our observations may have implications for human tasks that require postural stability.
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Introduction Multi-source feedback (MSF) is an evaluation method mandated by the Accreditation Council for Graduate Medical Education (ACGME). The Queen's Simulation Assessment Tool (QSAT) has been validated as being able to distinguish between resident performances in a simulation setting. The QSAT has also been demonstrated to have excellent MSF agreement when used in an adult simulation performed in a simulation lab. Using the QSAT, this study sought to determine the degree of agreement of MSF in a single pediatric (Peds) simulation case conducted in situ in a Peds emergency department (ED). Methods This Institutional Review Board-approved study was conducted in a four-year emergency medicine residency. A Peds resuscitation case was developed with specific behavioral anchors on the QSAT, which uses a 1-5 scale in each of five categories: Primary Assessment, Diagnostic Actions, Therapeutic Actions, Communication, and Overall Assessment. Data was gathered from six participants for each simulation. The lead resident self-evaluated and received MSF from a junior peer resident, a fixed Peds ED nurse, a random ED nurse, and two faculty (one fixed, the other from a dyad). The agreement was calculated with intraclass correlation coefficients (ICC). Results The simulation was performed on 35 separate days over two academic years. A total of 106 MSF participants were enrolled. Enrollees included three faculty members, 35 team leaders, 34 peers, 33 ED registered nurses (RN), and one Peds RN; 50% of the enrollees were female (n=53). Mean QSAT scores ranged from 20.7 to 23.4. A fair agreement was demonstrated via ICC; there was no statistically significant difference between sources of MSF. Removing self-evaluation led to the highest ICC. ICC for any single or grouped non-faculty source of MSF was poor. Conclusion Using the QSAT, the findings from this single-site cohort suggest that faculty must be included in MSF. Self-evaluation appears to be of limited value in MSF with the QSAT. The degree of MSF agreement as gathered by the QSAT was lower in this cohort than previously reported for adult simulation cases performed in the simulation lab. This may be due to either the pediatric nature of the case, the location of the simulation, or both.
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INTRODUCTION: The Toxicology Investigators Consortium (ToxIC) database, created in 2010 by the American College of Medical Toxicology (ACMT), compiles data recorded by medical toxicologists. In January 2017, the data field for transgender (and if transgender, male-to-female or female-to-male) was added to the ToxIC form. Little is known regarding trends in poisonings among transgender patients. We sought to review consultations managed by a bedside toxicologist and provide descriptive data in trends among types of exposures within the transgender demographic. METHODS: A retrospective ToxIC database evaluation of cases in which the patient identified as transgender were reviewed from January 2017-June 2019 and descriptive demographics reported. RESULTS: The registry contained 113 cases that involved transgender patients. Of those with complete data, 41 (36.6%) were male-to-female, 68 (60.7%) were female-to-male, and 3 (2.7%) identified as gender non-conforming. Of those with complete data, the most common reason for encounter was intentional use of a pharmaceutical drug (N = 97, 85.8%), of which 85 (87.6%) were classified as intentional pharmaceutical use intended for self-harm. Analgesics were the most common class of drugs used out of those reported (N = 24, 22%). Forty-six (90.2%) patients aged 13-18 with complete data were identified as encounters due to self-harm. Attempt at self-harm was the most common reason for intentional pharmaceutical encounter among the sample of transgender patients with complete data (N = 85, 87.6%); with female-to-male patients having an N = 53 (77.9%). CONCLUSION: Among transgender patients in the ToxIC registry, the most common primary reason for the encounter was intentional use of a pharmaceutical drug intended for self-harm. In this small cohort, there were some age and transition differences in prevalence. These findings may inform poisoning prevention practices as well as sex- and gender-based management of patients in this vulnerable population.
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Sobredosis de Droga/diagnóstico , Toxicología Forense , Detección de Abuso de Sustancias , Trastornos Relacionados con Sustancias/diagnóstico , Intento de Suicidio , Personas Transgénero , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Bases de Datos Factuales , Sobredosis de Droga/epidemiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Sistema de Registros , Estudios Retrospectivos , Trastornos Relacionados con Sustancias/epidemiología , Estados Unidos/epidemiología , Adulto JovenRESUMEN
The risk of opioid use disorder among patients with sickle cell disease who are treated with chronic opioids remains unclear, but the complications associated with opioid use and overdose can be accentuated in those with sickle cell disease. In this case report, we describe a 13-year-old girl with sickle cell disease who presented to the emergency department after a morphine overdose causing renal infarction, acute kidney injury, acute respiratory distress syndrome, and posterior reversible encephalopathy syndrome.
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Analgésicos Opioides , Anemia de Células Falciformes , Trastornos Relacionados con Opioides , Síndrome de Leucoencefalopatía Posterior , Adolescente , Analgésicos Opioides/efectos adversos , Anemia de Células Falciformes/tratamiento farmacológico , Servicio de Urgencia en Hospital , Femenino , Humanos , Trastornos Relacionados con Opioides/tratamiento farmacológicoRESUMEN
BACKGROUND: Variations between male and female populations are previously reported in classes of harmfully used/misused drugs, severity of substance use disorder and risk of relapse. The aim of this study was to provide a review of bedside medical toxicologist managed, sex-specific poisonings in adults that present with harmful drug use/misuse. METHODS: ToxIC Registry cases ≥19 and ≤65 years old, with harmful drug use or misuse during the timeframe June 2010-December 2016, were studied. Demographics, primary agents of toxic exposure, administration route and complications were analyzed. Descriptive methods were used in the analysis. RESULTS: The database included 51,440 cases. Of these, 3426 cases were analyzed in which the primary reason for the encounter was harmful substance use/misuse. Females were found to harmfully use/misuse pharmaceutical drugs (N=806, 65.6%) more than nonpharmaceutical drugs (N=423, 34.4%). Males more frequently used nonpharmaceutical drugs (N=1189, 54.1%) than pharmaceutical drugs (1008, 45.9%). Analgesics were used by females (N= 215, 18.2%) and males (N=137, 6.6%). Sedative hypnotics were used by females (N=165, 14%) and males (N=160, 7.8%). Psychoactive agents were used by males (N=325, 15.8%) and females (N=67, 5.7%). Sympathomimetics were used by males (N=381, 18.5%) and females (N=151, 12.8%). The majority of both male and female participants, 1712 (57.9%), utilized an oral route of administration. However, 312 (16.5%) of males utilized inhalation vs 73 (6.8%) of females inhaled their substance. CONCLUSION: There were sex-specific differences among patients evaluated for harmful substance use/misuse by toxicologists. Considering these differences in regards to management and preventive approaches may be indicated.
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OBJECTIVE: To review pediatric poisonings evaluated at the bedside by medical toxicologists and reported in the ToxIC registry, by sex and age group. METHODS: Pediatric poisoning cases age ≤18 years, reported between January 2010 and December 2016, were reviewed. Descriptive statistics were used to describe study variables by age group and sex. RESULTS: A total of 12,699 cases were analyzed. There were 7517 females and 5182 males. Those < 2 years old represented 12.5% of the study group (n = 1584), 17.2% were 2-6 years old (n = 2178), 8.6% were 7-12 years old (n = 1097), and 61.7% were 13-18 years old (n = 7840). The most common primary reasons for encounter were intentional pharmaceutical with 4900 females and 1836 males; intentional non-pharmaceutical with 952 females and 1213 males; unintentional pharmaceutical with 539 females and 644 males; and unintentional non-pharmaceutical with 435 females and 593 males. Overall, pharmaceuticals were the most commonly involved agents, including analgesics (20.9% of cases) and antidepressants (11% of cases): 27.8% of females and 10.7% of males were reportedly exposed to an analgesic.13.7% of females and 7.0% of males were reportedly exposed to an antidepressant. Among 1584 cases under 2 years, there were 747 females and 837 males; among 2178 cases aged 2-6 years, there were 954 females and 1224 males; among 1097 cases aged 7-12 years, there were 555 females and 542 males; and among 7840 cases aged 13-18 years, there were 5261 females and 2579 males. Death was reported in 0.7% of the cases: 20 females and 18 males. 6.1% of cases were managed with intubation: 421 females and 351 males. CONCLUSIONS: Sex-based characteristics of poisonings varied by age group among pediatric poisoning presentations reported to the ToxIC registry and further research is needed to determine implications for education and prevention efforts.
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Intoxicación/epidemiología , Adolescente , Distribución por Edad , Niño , Preescolar , Bases de Datos Factuales , Femenino , Humanos , Lactante , Masculino , Intoxicación/diagnóstico , Sistema de Registros , Distribución por Sexo , Factores de TiempoRESUMEN
Nitromethane, methanol, and oil are the common components of radio-controlled (R/C) vehicle fuels. Nitromethane can cause a false elevation of serum creatinine concentration as measured by the widely used Jaffe colorimetric method. We gathered data from our poison control system and from previously published case reports to see if a correlation exists between serum methanol concentrations and spuriously elevated serum creatinine concentrations after human exposures to R/C fuel. The California Poison Control System (CPCS) computerized database was queried for all cases of human exposure to R/C vehicle fuel reported between December 1, 2002 and December 1, 2004. Serum creatinine and methanol concentrations were recorded when available, as was the method used to determine serum creatinine. A MEDLINE search was used to obtain previously published cases of human nitromethane exposure associated with falsely elevated creatinine concentrations. During the 2-year period, serum creatinine concentrations were recorded in 7 of 26 R/C fuel exposures (all ingestions), and 6 of these were abnormal (range of 1.9-11.5 mg/dL). In this series, the higher the serum creatinine concentration measured by Jaffe method, the higher the serum methanol concentration. The MEDLINE search yielded data from six previously published case reports on this topic. The data from these case reports seem to follow the trend seen in our case series. These data suggest that a spuriously elevated serum creatinine (by Jaffe method) may have value as an early surrogate marker of methanol poisoning in those who ingest R/C fuel. Also, the degree to which the serum creatinine is elevated may indicate the severity of methanol poisoning.
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Creatinina/sangre , Metano/análogos & derivados , Metanol/sangre , Metanol/envenenamiento , Nitroparafinas/envenenamiento , Adolescente , Adulto , Niño , Colorimetría , Femenino , Gasolina , Humanos , Actividades Recreativas , Masculino , Metano/envenenamiento , Estudios RetrospectivosRESUMEN
It was observed previously that New Zealand blackcurrant (NZBC) extract reduced slowing of the maximal 15 m sprint speed during the Loughborough Intermittent Shuttle Test. We examined the effect of NZBC extract on the performance of the Running Based Anaerobic Sprint Test (RAST, 6 × 35-m sprints with 10 seconds passive recovery) in trained youth and recreationally active football players. Fifteen recreationally active (University team) (age: 20 ± 1 years, height: 174 ± 19 cm, body mass: 80 ± 13 kg) and nine trained youth players (English professional club) (age: 17 ± 0 years, height: 178 ± 8 cm, body mass: 69 ± 9 kg, mean ± SD) participated in three testing sessions. Prior to the RASTs, participants consumed two capsules of NZBC extract (600 mgâday-1 CurraNZ®) or placebo (P) for 7 days (double blind, randomised, cross-over design, wash-out at least 14 days). Ability difference between groups was shown by sprint 1 time. In the placebo condition, trained youth players had faster times for sprint 1 (5.00 ± 0.05 s) than recreationally active players (5.42 ± 0.08 s) (p < 0.01). In trained youth players, there was a trend for an effect of NZBC extract (p = 0.10) on the slowing of the sprint 1 time. NZBC extract reduced slowing of the sprint 5 time (P: 0.56 ± 0.22 s; NZBC: 0.35 ± 0.25, p = 0.02) and this was not observed in recreationally active players (P: 0.57 ± 0.48 s; NZBC: 0.56 ± 0.33, p = 0.90). For fatigue index, expressed as a % change in fastest sprint time, there was a strong trend to be lower in both trained youth and recreationally active players combined by NZBC extract (P: -13 ± 7%; NZBC: -11 ± 6%, p = 0.06) with 12 participants (five trained youth) experiencing less fatigue. New Zealand blackcurrant extract seems to benefit repeated sprint performance only in trained football players.
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New Zealand blackcurrant (NZBC) extract increased 16.1 km cycling time trial performance. The aim of the present study was to examine the effect of NZBC extract on 2 × 4 km time trial performance. Ten male cyclists (age: 30 ± 12 years, body mass: 74 ± 9 kg, height: 179 ± 7 cm, body fat: 11 ± 3%, (VÌ) ÌO2max: 55 ± 7 mLâ¢kg-1â¢min-1, mean ± SD) volunteered. Participants were familiarized with the time trials. Participants consumed capsulated NZBC extract (300 mgâday-1 CurraNZ™; containing 105 mg anthocyanin) or placebo for seven days (double blind, randomised, cross-over design, wash-out at least seven days) before 2 × 4 km time trials (10 min active self-paced recovery between trials) (SRM ergometer, SRM International, Germany). Heart rate was recorded and blood lactate sampled immediately after each trial and 8 min into recovery between the trials. Times over comparable one km distances in each 4 km time trial were similar. No effect was observed for the time to complete the first (placebo: 380 ± 28 s, NZBC: 377 ± 27 s) and second 4 km of cycling (placebo: 391 ± 32 s, NZBC: 387 ± 30 s), within both groups the second 4 km times slower by 11 ± 8 s and 11 ± 9 s for placebo and NZBC, respectively. However, the total time of the two 4 km cycling trials was 0.82% faster with NZBC extract (placebo: 771 ± 60 s, NZBC 764 ± 56 s, p = 0.034) with seven participants having faster total times. There was no effect of NZBC on heart rate and lactate values at identical time points. New Zealand blackcurrant extract seems to be beneficial in repeated short-distance cycling time trials for overall performance.
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Acatisia Inducida por Medicamentos/etiología , Benzodioxoles/efectos adversos , Cosméticos/efectos adversos , Drogas de Diseño/efectos adversos , Drogas Ilícitas/efectos adversos , Conducta Paranoide/inducido químicamente , Pirrolidinas/efectos adversos , Trastornos Relacionados con Sustancias/diagnóstico , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Benzodioxoles/sangre , Drogas de Diseño/química , Urgencias Médicas , Humanos , Hipertensión/inducido químicamente , Drogas Ilícitas/análisis , Drogas Ilícitas/legislación & jurisprudencia , Masculino , Mercadotecnía/legislación & jurisprudencia , Midriasis/inducido químicamente , Pennsylvania , Pirrolidinas/sangre , Taquicardia/inducido químicamente , Cathinona SintéticaRESUMEN
A 34-year-old man was found down in a parking lot after huffing fifteen cans of Dust-Off. Though lucid during the initial hospital evaluation, the patient experienced a generalized seizure followed by a torsades de pointes arrhythmia and was resuscitated. An echocardiogram revealed left and right ventricular dysfunction with an ejection fraction of 25%. This unique outcome of inhalant abuse has scarcely been reported in similar cases. The patient fully recovered and had a normal ejection fraction prior to discharge.
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Xyloglucan is the most abundant hemicellulose in the primary cell wall of dicotyledonous plants. In Arabidopsis, three xyloglucan xylosyltransferases, XXT1, XXT2, and XXT5, participate in xylosylation of the xyloglucan backbone. Despite the importance of these enzymes, there is a lack of information on their structure and the critical residues required for substrate binding and transferase activity. In this study, the roles of different domains of XX2 in protein expression and catalytic activity were investigated by constructing a series of N- and C-terminal truncations. XXT2 with an N-terminal truncation of 31 amino acids after the predicted transmembrane domain showed the highest protein expression, but truncations of more than 31 residues decreased protein expression and catalytic activity. XXT2 constructs with C-terminal truncations showed increased protein expression but decreased activity, particularly for truncations of 44 or more amino acids. Site-directed mutagenesis was also used to investigate six positively charged residues near the C-terminus and found that four of the mutants showed decreased enzymatic activity. We conclude that the N- and C-termini of XXT2 have important roles in protein folding and enzymatic activity: the stem region (particularly the N-terminus of the catalytic domain) is critical for protein folding and the C-terminus is essential for enzymatic activity but not for protein folding.
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Glucanos/química , Pentosiltransferasa/química , Xilanos/química , Arabidopsis/enzimología , Arabidopsis/metabolismo , Pared Celular/metabolismo , Mutagénesis Sitio-Dirigida , Pentosiltransferasa/genética , Pentosiltransferasa/metabolismo , Tallos de la Planta/metabolismoRESUMEN
Hookah smoking, at one time confined to North Africa, the eastern Mediterranean region, the Arabian peninsula, and Southeast Asia, has begun to spread throughout the world. As some practices of eastern and Arab cultures reach the United States, the number of people using hookah on an experimental or regular basis has increased. Carbon monoxide poisoning can be a common adverse effect, possibly undetected by physicians, in hookah smokers. The authors report a case of carbon monoxide poisoning secondary to smoking tobacco through a hookah.