Germline and sporadic cancers driven by the RAS pathway: parallels and contrasts.

Somatic mutations in RAS and related pathway genes such as NF1 have been strongly implicated in the development of cancer while also being implicated in a diverse group of developmental disorders named the 'RASopathies', including neurofibromatosis type 1 (NF1), Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NSML), Costello syndrome (CS), cardiofaciocutaneous syndrome (CFC), and capillary malformation-arteriovenous syndrome (CM-AVM). It remains unclear why (i) there is little overlap in mutational subtype between Ras-driven malignancies associated with sporadic disease and those associated with the RASopathy syndromes, and (ii) RASopathy-associated cancers are usually of different histological origin to those seen with sporadic mutations of the same genes. For instance, germline variants in KRAS and NRAS are rarely found at codons 12, 13 or 61, the most common sites for somatic mutations in sporadic cancers. An exception is CS, where germline variants in codons 12 and 13 of HRAS occur relatively frequently. Given recent renewed drug interest following early clinical success of RAS G12C and farnesyl transferase inhibitors, an improved understanding of this relationship could help guide targeted therapies for both sporadic and germline cancers associated with the Ras pathway.

Cloning and expression of pinB gene from Triticum monococum seeds.

Puroindolines (PIN) are low molecular weight, cysteine-rich, endosperm-specific, basic proteins with a unique tryptophan-rich domain found in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) as well as other members of Triticaceae. PINs appear to be involved in both flour softness as well as resistance against fungal diseases. These proteins are known to be the major components of 'friabilin' associated with the surface of water washed starch grains and possess lipid binding properties. Structural characterization of puroindolines from Triticum monococum was initiated by amplifying and subsequently cloning the corresponding pin gene into an expression vector, known as pET-32a(+). The protein contains five tryptophanin domains and ten cysteine residues. The pinB gene was fused with the 109aa Trx.Tag thioredoxin for a high-level expression. The cloning sites used for producing fusion proteins also contained cleavable His.Tag and S.tag sequences for detection and purification. After transformation of competent Origami cells, fusion protein expression was detected by growing a transformant in LB medium in the presence of 0.1 mM IPTG at room temperature for 6 hrs on a shaker. Both soluble and insoluble fusion proteins were extracted from Origami cells after sonication. Ni-NTA column (Qiagen) was used to extract and purify these fractions. Following an overnight digestion of the recombinant protein with enterokinase at room temperature, the corresponding fractions were electrophoresed in polyacrylamide gel, electroblotted onto a nitrocellulose membrane and cross-reacted with the anti-friabilin monoclonal antibody. We found that the recombinant PINB protein had a molecular weight of 16 kDa whereas TrxB was 21 kDa. Fusion protein ran at 34 kDa. PINB protein from wheat was shown to be immunologically related to a homologue, tryptophanin, in oat seed. Further study is currently underway to characterize these proteins structurally using NMR.

ECT as a therapeutic option in severe brain injury.

Electroconvulsive therapy (ECT) is a safe, highly effective, and rapidly acting treatment for certain major psychiatric illnesses, most notably severe mood disorders. Disturbances in mood and behavior as symptoms of delirium may complicate recovery from traumatic brain injury, but virtually no data exist on the role of ECT as a treatment modality in such clinical situations. We describe a patient with severe, unremitting, agitated behavior following a severe closed head injury from a motor vehicle accident. The initial Glasgow Coma Scale score was 3, with computed tomographic evidence of bilateral frontal and left thalamic contusions. After awakening from a 21-day coma, the patient failed to improve beyond a Ranchos Los Amigos level 4 recovery stage. He exhibited persistent severe agitation with vocal outbursts and failed to assist in performing activities of daily living. His difficulties proved unresponsive to combined behavioral therapy and multiple trials of various psychopharmacologic agents. As an intervention of "last resort," he then received six brief-pulse, bilateral ECT treatments that resulted in marked lessening of his agitation and improvement in his ability to express his needs and participate in his self-care. Also, following the ECT, he showed a markedly enhanced response to psychopharmacologic agents. These findings may have important clinical implications for treatment of prolonged delirium after traumatic brain injury.

Listening to older patients.

This article presents findings from focus-group research conducted by Age Wave, Inc., a marketing services, research and consulting firm focusing on the 50+ market. The research is part of a comprehensive study on the aging-readiness of acute-care hospitals, sponsored by Baxter Healthcare Corporation. The findings discussed here are based on focus groups conducted in April 1993 with recently discharged 50+ patients in 10 major metropolitan/nonmetropolitan areas throughout the country. While findings from focus groups should be considered directional rather than absolute, the views of an expert panel confirm many of the observations and experiences of these older hospital patients.

A comparative rewarming trial of gastric versus peritoneal lavage in a hypothermic model.

A comparison of gastric lavage versus peritoneal lavage rewarming was studied in a hypothermic rabbit model. The gastric lavage group (n = 5) had a mean rewarming time of 136 +/- 25.1 minutes versus the peritoneal lavage group (n = 6) mean rewarming time of 131.7 +/- 27.9 minutes (p = .795). Good correlation was found between tympanic membrane temperature readings and both rectal temperature readings (r = .69) in the gastric lavage group and esophageal temperature readings (r = .90) in the peritoneal lavage group. Gastric lavage and peritoneal lavage have the same rewarming rates in the present hypothermic model.

Structure-anticonvulsant activity relationships of cannabidiol analogs.

Cannabidiol (CBD) exhibits anticonvulsant activity in experimental animals and in man. As part of a structure-activity study, analogs were prepared wherein the terpene unit, the aryl unit, and/or the side chain were modified. Thus, several pinenyl and carenyl derivatives, aryl ethers and acetates, and a variety of 1",1"-dialkylhexyl and 1",1"-dialkylheptyl analogs were synthesized. The compounds were evaluated for anti-convulsant activity in seizure susceptible (AGS) rats and for neurotoxicity in the rat rotorod (ROT) test. Comparisons of stereoisomers of CBD and several analogs revealed a general lack of stereoselectivity for anticonvulsant and other CNS properties of this class of compounds.

CT demonstration of hernia through an iliac crest defect.

We recently encountered two patients with an unusual hernia through a defect in the iliac crest secondary to prior bone graft harvesting. The radiographic and CT features of this rare entity are illustrated and pertinent literature reviewed.

Stochastic models for X chromosome inactivation.

A multivariate Gaussian model for mammalian development is presented with the associated biological and mathematical assumptions. Many biological investigations use the female mammal X chromosome to test hypotheses and to estimate parameters of the developmental system. In particular, Lyon's (1961) hypotheses are used as a basis of the mathematical model. Experimental mouse data and three sets of human experimental data are analyzed using the hypothesized Gaussian model. The estimated biological parameters are consistent with some current biological theories.