Butanol, an alcohol which can be produced from biomass sources, has received recent interest as an alternative to gasoline for use in spark ignition engines and as a possible blending compound with fossil diesel or biodiesel. Therefore, the autoignition of the four isomers of butanol (1-butanol, 2-butanol, iso-butanol, and tert-butanol) has been experimentally studied at high temperatures in a shock tube, and a kinetic mechanism for description of their high-temperature oxidation has been developed. Ignition delay times for butanol/oxygen/argon mixtures have been measured behind reflected shock waves at temperatures and pressures ranging from approximately 1200 to 1800 K and 1 to 4 bar. Electronically excited OH emission and pressure measurements were used to determine ignition-delay times. The influence of temperature, pressure, and mixture composition on ignition delay has been characterized. A detailed kinetic mechanism has been developed to describe the oxidation of the butanol isomers and validated by comparison to the shock-tube measurements. Reaction flux and sensitivity analysis illustrates the relative importance of the three competing classes of consumption reactions during the oxidation of the four butanol isomers: dehydration, unimolecular decomposition, and H-atom abstraction. Kinetic modeling indicates that the consumption of 1-butanol and iso-butanol, the most reactive isomers, takes place primarily by H-atom abstraction resulting in the formation of radicals, the decomposition of which yields highly reactive branching agents, H atoms and OH radicals. Conversely, the consumption of tert-butanol and 2-butanol, the least reactive isomers, takes place primarily via dehydration, resulting in the formation of alkenes, which lead to resonance stabilized radicals with very low reactivity. To our knowledge, the ignition-delay measurements and oxidation mechanism presented here for 2-butanol, iso-butanol, and tert-butanol are the first of their kind.

Objectives: Limited data exist regarding the management of hypertension in pediatric patients on mechanical circulatory support. Hypertension is a known risk factor for stroke and low cardiac output in patients requiring mechanical circulatory support and a narrow therapeutic window of blood pressure is often targeted. Traditional short-acting infusions to treat hypertension, such as sodium nitroprusside, may lead to accumulation of toxic metabolites in patients with renal dysfunction. Our primary objective was to describe use of clevidipine, a continuous short-acting calcium channel blocking medication, for blood pressure control in pediatric patients on mechanical circulatory support. Design: Single-center retrospective cohort study. Setting: A 26-bed quaternary cardiovascular ICU in a university-based pediatric hospital in California. Patients: Mechanical circulatory support patients admitted to cardiovascular ICU who received clevidipine infusions between October 1, 2016, and March 31, 2019. Interventions: Clevidipine infusion. Measurements and Main Results: Data from a cohort of 38 patients who received a total of 45 clevidipine infusions were reviewed. The cohort had a median age of 2.7 years and included neonates. No patient had record of hypotensive events, code events, or received low-dose epinephrine or code-dosed epinephrine related to a clevidipine infusion. Median duration of clevidipine infusion was 4.1 days (1.5–9.2 d). Eleven patients transitioned from clevidipine to enteral antihypertensive agents, and 26 clevidipine infusions were administered as a single agent without sodium nitroprusside. Seven patients were switched from sodium nitroprusside to clevidipine to avoid cyanide toxicity, a majority of whom had elevated serum creatinine. Conclusions: In this pediatric cardiac cohort, clevidipine infusions were effective at hypertension management and were not associated with hypotensive or code events. This report details the largest cohort and longest duration of clevidipine administration within a pediatric population and did not demonstrate hypotensive events, even among neonatal populations. Clevidipine may be a reasonable cost-effective alternative antihypertensive medication compared to traditional short-acting agents.

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In this report, we review the evolution of bacillus Calmette-Guérin (BCG) immunotherapy as a legitimate form of treatment in superficial, nonmuscle-invasive bladder cancer. In the US, an estimated 45,000 new cases of bladder cancer are diagnosed each year and the annual death rate approaches 11,000. Approximately 70 percent of these cancers are superficial at the time of initial presentation. The treatment of superficial bladder cancer has three objectives: (1) eradication of existing disease, (2) prophylaxis against tumor recurrence, and (3) prevention of tumor progression (either muscular invasion, metastatic spread, or both). Cystectomy generally is reserved for muscle-invasive disease. Transurethral resection of the bladder tumor is the preferred initial therapy. Intravesical instillations of various chemotherapeutic agents following transurethral resection have been extensively investigated. Some of the common agents used include thiotepa, mitomycin, and doxorubicin. Despite such treatment efforts, however, over 40 percent of patients with superficial bladder cancer experience a recurrence of their tumor within three years. Approximately half of these recurrences either present as less-well-differentiated tumors or have already penetrated into the bladder musculature, metastasized, or both. Since Morales et al. first introduced intravesical BCG vaccine for prophylaxis as well as for treatment of superficial bladder tumors in 1976, support has grown rapidly for its use as an alternative to chemotherapy. When used with prophylactic intent following transurethral resection, recurrence rates are lower than those achieved with other agents. In addition, BCG is emerging as the consensus drug of choice for treating carcinoma in situ of the bladder. The mechanisms by which BCG exerts its antitumor activity remain largely unknown. BCG is thought to stimulate a localized, nonspecific inflammatory response that leads to subsequent shedding of tumor cells. A large body of clinical and experimental data suggest an association between the development of an immunologic response to BCG and successful antitumor activity. No universally accepted therapeutic regimen has been agreed upon. One regimen commonly used consists of an ampul of BCG mixed with 50 mL of NaCl 0.9%, instilled once a week for six weeks and retained for two hours prior to voiding. Maintenance therapy generally consists of intravesical doses given at three-month cycles for at least two years of recurrence-free follow-up. Because BCG is a biologic agent, the commercially available products may differ in weight, colony-forming units per vial, and antigenicity. How these product characteristics affect clinical responsiveness to different strains of BCG remains unanswered.

Ketorolac exhibits an anesthetic-sparing quality similar to that observed with narcotic analgesics.

Although the number of reported cases of leishmaniasis in the US has generally been low, there is a possibility that more cases may be reported in the future because of the large number of military personnel returning to this country from endemic areas. Medical personnel, particularly those working in governmental institutions, should be familiar with the pathogenesis of this unusual infection as well as potential treatment options.

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