RESUMEN
Hemispherectomy is a neurosurgical procedure that is frequently performed in pediatric patients diagnosed with Rasmussen's encephalitis. Postoperative complications include immediate complications such as hydrocephalus and hemorrhage and behavioral complications such as language impairments and contralateral weakness. However, there are limited studies or case reports that address the potential endocrinopathies associated with this and other pediatric epileptic surgeries. This case report describes the endocrinopathies following an anatomical hemispherectomy procedure. A four-year-old African-American female had a right anatomical hemispherectomy for the treatment of Rasmussen's encephalitis in 2020. The postoperative course was immediately complicated by central diabetes insipidus which was stabilized with desmopressin. The patient's labs in 2021 were consistent with central precocious puberty with elevated luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Additionally, the patient was found to have secondary adrenal insufficiency in which she failed a low-dose adrenocorticotropic hormone (ACTH) stimulation test. Oral hydrocortisone therapy was initiated for secondary adrenal insufficiency in addition to initiating leuprolide injections for central precocious puberty. Furthermore, at the age of seven years, the patient had her first menarche. This case report emphasizes the need for closer and long-term surveillance for endocrine issues in postepileptic surgical pediatric patients as well as a surveillance plan for the development of other potential endocrine abnormalities throughout the patient's life.
RESUMEN
The high sensitivity of silole- and silafluorene-containing polymers for detecting organic nitro, nitrate, and nitramine explosives cannot be solely attributed to favorable analyte-polymer hydrophobic interactions and amplified fluorescence quenching due to delocalization along the polymer chain. The Lewis acidity of silicon in conjugated poly(silafluorene-vinylene)s is shown to be important. This was established by examining the (29)Si NMR chemical shifts (Delta) for the model trimer fragment of the polymer CH(3)-silafluorene-(trans-C(2)H(2))-silafluorene-(trans-C(2)H(2))-silafluorene-CH(3). The peripheral and central silicon resonances are up-field from a TMS reference at -9.50 and -18.9 ppm, respectively. Both resonances shift down-field in the presence of donor analytes and the observed shifts (0 to 1 ppm) correlate with the basicity of a variety of added Lewis bases, including TNT. The most basic analyte studied was acetonitrile and an association constant (K(a)) of 0.12 M(-1) was calculated its binding to the peripheral silicon centers using the Scatchard method. Spin-lattice relaxation times (T(1)) of 5.86(3) and 4.83(4) s were measured for the methyl protons of acetonitrile in benzene-d(6) at 20 degrees C in the absence and presence of the silafluorene trimer, respectively. The significant change in T(1) values further supports a binding event between acetonitrile and the silafluorene trimer. These studies as well as significant changes and shifts observed in the characteristic UV-Vis absorption of the silafluorene group support an important role for the Lewis acid character of Si in polymer sensors that incorporate strained silacycles. The nitro groups of high explosives may act as weak Lewis-base donors to silacycles. This provides a donor-acceptor interaction that may be crucial for orienting the explosive analyte in the polymer film to provide an efficient pathway for inner-sphere electron transfer during the electron-transfer quenching process.
RESUMEN
The detection of trace explosives is important for forensic, military, and homeland security applications. Detection of widely used nitroaromatic explosives (trinitrotoluene [TNT], 2,4-dinitrotoluene [DNT], picric acid [PA]) was carried out using photoluminescent metallole-containing polymers. The method of detection is through the quenching of fluorescence of thin films of the polymer, prepared by spray coating organic solutions of the polymer, by the explosive analyte. Visual quenching of luminescence (lambda(em) approximately 400-510 nm) in the presence of the explosive is seen immediately upon illumination with near-UV light (lambda(ex)=360 nm). Detection limits were observed to be as low as 5 ng for TNT, 20 ng for DNT, and 5 ng for PA. In addition, experiments with normal production line explosives and their components show that this technology is also able to detect composition B, Pyrodex, and nitromethane. This method offers a convenient and sensitive method of detection of trace nitroaromatic explosive residue.
RESUMEN
Detection of trace quantities of explosive residues plays a key role in military, civilian, and counter-terrorism applications. To advance explosives sensor technology, current methods will need to become cheaper and portable while maintaining sensitivity and selectivity. The detection of common explosives including trinitrotoluene (TNT), cyclotrimethylenetrinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, 2,4,6-trinitrophenyl-N-methylnitramine, and trinitroglycerin may be carried out using a three-step process combining "turn-off" and "turn-on" fluorimetric sensing. This process first detects nitroaromatic explosives by their quenching of green luminescence of polymetalloles (lambda em approximately 400-510 nm). The second step places down a thin film of 2,3-diaminonaphthalene (DAN) while "erasing" the polymetallole luminescence. The final step completes the reaction of the nitramines and/or nitrate esters with DAN resulting in the formation of a blue luminescent traizole complex (lambda(em) = 450 nm) providing a "turn-on" response for nitramine and nitrate ester-based explosives. Detection limits as low as 2 ng are observed. Solid-state detection of production line explosives demonstrates the applicability of this method to real world situations. This method offers a sensitive and selective detection process for a diverse group of the most common high explosives used in military and terrorist applications today.