Local Coordination Environment of 3d and 4d Transition Metal Ions in LiCl-KCl Eutectic Mixture

In this study, the structure and coordination environment of two 3d transition elements (Ni and Cr) is investigated in a molten chloride salt system. Electronic absorption spectroscopy was employed to elucidate their coordination environment in 3LiCl-2KCl eutectic salt, as a function of temperature. Density functional theory (DFT) modeling was used to determine the coordination environment of the transition metal species in the eutectic composition as well as the optical spectra computationally. The Ni²⁺and Cr³⁺ exist in a tetrahedral and octahedral coordination environment, respectively, in eutectic salt. The spectra thus obtained were compared with the experimental data; a reasonable qualitative agreement was obtained between experimental and computational Ni²⁺ and Cr³⁺spectra, and the coordination of both elements in the eutectic composition were in excellent agreement with the experimentally determined results. Computational results were also obtained for two 4d elements, Mo³⁺ and Nb³⁺, with both quantum molecular dynamics (QMD) and hybrid functional optical spectra indicating octahedral coordination.     

RASSF1A independence and early galectin‐1 upregulation in PIK3CA‐induced hepatocarcinogenesis: new therapeutic venues

Aberrant activation of the phosphoinositide 3‐kinase (PI3K)/AKT/mTOR and Ras/mitogen‐activated protein kinase (MAPK) pathways is a hallmark of hepatocarcinogenesis. In a subset of hepatocellular carcinomas (HCCs), PI3K/AKT/mTOR signaling dysregulation depends on phosphatidylinositol‐4,5‐bisphosphate 3‐kinase, catalytic subunit alpha (PIK3CA) mutations, while RAS/MAPK activation is partly attributed to promoter methylation of the tumor suppressor Ras association domain‐containing protein 1 (RASSF1A). To evaluate a possible cocarcinogenic effect of PIK3CA activation and RASSF1A knockout, plasmids expressing oncogenic forms of PIK3CA (E545K or H1047R mutants) were delivered to the liver of RASSF1A knockout and wild‐type mice by hydrodynamic tail vein injection combined with sleeping beauty‐mediated somatic integration. Transfection of either PIK3CA E545K or H1047R mutants sufficed to induce HCCs in mice irrespective of RASSF1A mutational background. The related tumors displayed a lipogenic phenotype with upregulation of fatty acid synthase and stearoyl‐CoA desaturase‐1 (SCD1). Galectin‐1, which was commonly upregulated in preneoplastic lesions and tumors, emerged as a regulator of SCD1. Co‐inhibitory treatment with PIK3CA inhibitors and the galectin‐1 inhibitor OTX008 resulted in synergistic cytotoxicity in human HCC cell lines, suggesting novel therapeutic venues.     

Short Bowel Syndrome After Continence-Preserving Procedures

The short bowel syndrome (SBS) can result from a variety of conditions, including postoperative complications and malignancy. Continence-preserving operations are generally performed for either ulcerative colitis (UC) or familial polyposis (FAP). These procedures can be associated with high morbidity and the potential for future malignancy. Our aim was to determine the causes and consequences of SBS in patients undergoing these procedures. Twenty-four patients (12 men and 12 women) 18 to 64 years of age were identified with SBS after continence-preserving procedures. Eighteen had pelvic procedures, and six had continent ileostomies. All SBS patients had a proximal ostomy. Remnant length measured <60 cm in five patients, 60–120 cm in ten patients, and >120 cm in nine patients. Overall 13 patients required long-term PN. Four FAP patients with desmoid tumors died. One patient with UC underwent intestinal transplant and expired. Follow-up ranges from 6 to 192 months. Overall 14 patients had UC, nine had FAP, and one had functional disease. Eight patients with an initial diagnosis of UC had subsequent Crohn’s disease necessitating further resection and pouch excision. Eight patients (five with UC, two FAP, and one with functional disease) had postoperative complications, including obstruction or mesenteric ischemia requiring resections. One UC patient developed adenocarcinoma in a continent ileostomy. Seven of the nine FAP patients required resection for desmoid tumors. Six of these underwent resection alone. Three died at 10, 11, and 13 months after SBS from liver failure and sepsis while awaiting transplant. One patient has recurrent desmoid at 30 months, another is alive and well at 48 months, and the other patient, who was not a transplant candidate, died from an unrelated cardiac operation at 23 months. A single patient underwent resection with simultaneous multivisceral transplantation. SBS can develop after continence-preserving procedures. This occurs with inflammatory bowel disease when unsuspected Crohn’s disease is present or complications occur. SBS related to desmoid tumors has a poor prognosis in patients undergoing resection alone. A more aggressive approach to intestinal transplantation in these patients may be warranted.     

Trauma and burns in children

Trauma is the leading cause of death and disability in children, most often resulting from blunt trauma. An immediate co-ordinated and pathology-focussed resuscitation will contribute to improved morbidity and mortality outcomes. This article discusses the principles of the primary and secondary survey in injured children and outlines the management of children suffering from burns. A multi-professional approach to the treatment of critically injured children should be adopted; where the primary survey aims to identify and manage catastrophic haemorrhage followed by management of life-threatening injuries to airway, breathing and circulation. The secondary survey includes a detailed examination to identify and manage other subtle or less severe injuries. Attention to fluid therapy, analgesia, thermoregulation, blood coagulation and glucose homeostasis form important aspects of this secondary survey. Children injured in fires may have suffered from smoke inhalation or sustained burns to the upper airway, with rapid swelling of mucosal tissue, which can make immediate control of the airway very challenging. Both flame burns and scalds can cause significant fluid losses and are associated with a significant risk of mortality.     

Total right ventricular dependent coronary circulation in pulmonary atresia with intact ventricular septum

This report describes the case of a full-term gestational female with a prenatal diagnosis of pulmonary atresia with intact ventricular septum. Cardiac ultrasound at birth confirmed the diagnosis with no evidence of coronary artery fistulas. The patient died 6 hours after a central aortic to pulmonary artery shunt had been created with bypass support. Postmortem examination showed a coronary artery fistula rising from the right ventricle and a complete absence of both coronary ostia. This rare finding has been reported sporadically in the English literature.     

The angiogenic peptide pleiotrophin (PTN/HB-GAM) is expressed in fracture healing: an immunohistochemical study in rats

Introduction Formation of new blood vessels is essential for the process of fracture healing.Materials and methods We investigated the expression of the angiogenic factor pleiotrophin/HB-GAM in a closed fracture model in rats by immunohistochemical methods.Results Histologically, 5 days after fracture the callus was predominantly composed of fibrous tissue. On day 10 a prominent chondral callus connected both ends of the fractured tibia. There was a continuous transition from the chondral callus to the newly formed bone adjacent to the corticalis of the tibia. On day 15 the amount of woven bone had increased, and in 3 of 5 animals the proximal and distal tibiae were connected by a bridge of woven bone. Pleiotrophin could be immunostained in fibroblasts and endothelial cells of the fibrous tissue between the fractured tibia ends. The chondral callus remained largely pleiotrophin-negative. Only single chondrocytes adjacent to the newly formed bone were pleiotrophin-positive. On days 10 and 15 strong immunoreactivity for pleiotrophin in the well vascularized, newly formed, woven bone was detectable. Osteoblasts, endothelial cells and fibroblasts were strongly pleiotrophin-positive.Conclusions These results show the presence of the angiogenic peptide pleiotrophin during fracture healing.     

Femoral venous reflux abolished by greater saphenous vein stripping

Preoperative venous duplex scanning has revealed unexpected deep venous incompetence in patients with apparently only varicose veins. Acting on the hypothesis that the deep vein reflux was secondary to deep vein dilation caused by reflux volume, the following was done. Between July 1990 and April 1993, 29 limbs in 21 patients (16 females) were examined by color-flow duplex imaging to determine valve closure by the method of van Bemmelen. Instrumentation included high-resolution ATL-9 venous interrogation using a pneumatic cuff deflation stimulus of reflux in the standing, nonweight-bearing limb. All limbs showed greater saphenous vein reflux. Twenty-nine showed superficial femoral vein reflux and of these three showed popliteal vein reflux. Duplex testing was performed by a certified vascular technologist whose interpretation was blinded as to the results of clinical examination and grading of the severity of venous insufficiency. Surgery was performed on an outpatient basis under general anesthesia using groin-to-knee removal of the greater saphenous vein by the vein inversion technique of Van Der Strict. Stab avulsion of varicose tributary veins was accomplished during the same period of anesthesia. In 27 of 29 limbs with preoperative femoral reflux, that reflux was abolished by greater saphenous stripping. In patients with popliteal reflux both femoral and popliteal reflux was abolished. Improvement of deep venous hemodynamics by ablation of superficial reflux supports the reflux circuit theory of venous overload. Furthermore, preoperative evaluation of venous hemodynamics by duplex scanning appears to provide useful pre- and postoperative information regarding venous insufficiency in individual patients.Presented at the Twelfth Annual Meeting of the Southern California Vascular Surgical Society, Coronado, Calif, September 17–19, 1993.