Hyperosmolar hyperglycemic non ketotic coma and rhabdomyolysis; an uncommon clinical encounter

Rhabdomyolysis is usually attributed to trauma. However there is an association of rhabdomyolysis with hyperosmolar states. Recognition of this association will enable better management of the patient and reduce the burden on the care taker by preventing the onset of complications that can prove fatal. It is also important to realise that hyperosmolar coma can be the presenting complaint of a diabetic seeking medical attention for the first time.

Backbone and side-chain assignment of the lipidated and non-lipidated forms of the meningococcal outer membrane protein LP2086

LP2086 is a lipidated outer membrane protein from Neisseria meningitidis that elicits bactericidal antibodies and represents a promising vaccine candidate against meningococcal infections. Here we report the backbone and side-chain assignment for two forms of LP2086: non-lipidated in aqueous buffer and the lipidated protein in micellar solution.

Prospective pharmacogenetic analysis in advanced colorectal cancer (CRC) patients receiving first-line cetuximab-UFT-irinotecan therapy: Importance of gene polymorphisms related to antibody-dependent cellular cytotoxicity (ADCC)

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Background: Our purpose was to test the predictive value of germinal gene polymorphisms potentially linked to cetuximab, fluoropyrimidine and irinotecan pharmacodynamics on toxicity, clinical response, time to progression (TTP) and overall survival (OS). Methods: 52 patients with advanced CRC were enrolled in an ancillary pharmacogenetic study of the phase II CETUFTIRI trial (33 men, 19 women, mean age 63, range 36–84, PS 0–1). Treatment consisted in cetuximab (day 1-day 8-day 15, 250 mg/m2/week following a 400 mg/m2 loading dose) associated with irinotecan (day 1, 250 mg/m2) and UFT-folinic acid (day 1 to day 14, 250 mg/m2/day UFT, 90 mg/day folinic acid). Median number of administered cycles was 7 (range 1–8). The following gene polymorphisms were analyzed on blood genomic DNA: EGFR (CA repeats in intron 1, - 216G>T, -191C>A), EGF (61A>G), FCGR2A (131Arg>His), FCGR3A (158Phe>Val), UGT1A1 (TA repeats), TYMS (28 bp repeats including the G>C mutation on the 3R allele, 6 bp deletion in 3’ UTR), MTHFR (677C>T, 1298A>C). Results: Grade 3–4 toxicity was recorded in 59.6 % of patients. The toxicity score (sum of maximum grade for each toxicity pattern) was significantly linked to the FCGR2A genotype (median score 9, 9.5 and 13 in Arg/Arg, Arg/His and His/His patients, respectively, p = 0.035) and to the EGFR -191 genotype (median score 11 in CC patients versus 8.5 in CA patients, p = 0.040). Response rate was 49% (3 CR and 21 PR over 49 assessable patients) and was significantly higher in patients bearing the FCGR3A Val allele (62.1 % in Val/Val or Val/Phe versus 26.3 % in Phe/Phe, p = 0.020) or the TYMS 3RG allele (65.0 % versus 28.6 % in patients with no 3RG allele, p = 0.029). Gene polymorphisms did not influence TTP. A multivariate Cox analysis including gene polymorphisms and PS showed that overall survival was improved in patients bearing the FCGR3A Val allele (relative risk of death was 2.25 in Phe/Phe patients relative to Val-containing genotypes, 95% CI 1.03–4.91, p = 0.041). Conclusions: Present data suggest the importance of ADCC in cetuximab pharmacodynamics, as outlined by the role of FCGR gene polymorphisms on toxicity, responsiveness and survival.

No significant financial relationships to disclose.

The anatomic localization of circulating tumor cells and the immediate impact of surgery and radiofrequency ablation

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Background: There are few data on the impact of immediate and differing surgical interventions on circulating tumor cells (CTCs), nor their compartmentalization or localization in different anatomic vascular sites. Methods: CTCs from consecutive patients with colorectal liver metastases were quantitated prior to and immediately after open surgery, laparoscopic resection, open radiofrequency ablation (RFA) or percutaneous RFA. For individuals undergoing open surgery, either hepatic resections or open RFA, CTCs were examined in both systemic and portal circulation by measuring CTCs in samples derived from the peripheral vein, an artery, the portal vein and hepatic vein. Results: A total of 29 consecutive patients with colorectal liver metastases were included with a median age of 55 (range 30 - 88 years). CTCs were localized to the hepatic portosystemic macrocirculation with significantly greater numbers than in the systemic vasculature. Surgical procedures led to a statistically significant fall in CTCs at all sites measured (p<0.05). Conversely, RFA, either open or percutaneous was associated with an increase in CTCs. Conclusions: Surgical resection of metastases but not RFA decreases CTC levels. In patients with colorectal liver metastases, CTCs are localized to the hepatic (and probably pulmonary) macrocirculations. This may explain why metastases in sites other than the liver and lungs, are infrequently observed in cancer.

No significant financial relationships to disclose.

Structural Basis for the Immunogenic Properties of the Meningococcal Vaccine Candidate LP2086

LP2086 is a family of outer membrane lipoproteins from Neisseria meningitidis, which elicits bactericidal antibodies and are currently undergoing human clinical trials in a bivalent formulation where each antigen represents one of the two known LP2086 subfamilies. Here we report the NMR structure of the recombinant LP2086 variant B01, a representative of the LP2086 subfamily B. The structure reveals a novel fold composed of two domains: a "taco-shaped" N-terminal beta-sheet and a C-terminal beta-barrel connected by a linker. The structure in micellar solution is consistent with a model of LP2086 anchored to the outer membrane bilayer through its lipidated N terminus. A long flexible chain connects the folded part of the protein to the lipid anchor and acts as spacer, making both domains accessible to the host immune system. Antibodies broadly reactive against members from both subfamilies have been mapped to the N terminus. A surface of subfamily-defining residues was identified on one face of the protein, offering an explanation for the induction of subfamily-specific bactericidal antibodies.

Ahmed and Baerveldt glaucoma drainage implants: long-term results and factors influencing outcome

PURPOSE

To evaluate the clinical outcome of patients who received an Ahmed or Baerveldt implant for refractory glaucoma at the University Hospitals Leuven and to identify the factors which may influence the outcome.

METHODS

Retrospective study including 62 eyes with uncontrolled glaucoma, who underwent the implantation of a drainage device between January 2002 and December 2008. Criteria for complete success were an intraocular pressure (IOP) < or = 21 mmHg and > 5 mmHg, and a minimum 20% decrease in IOP compared to baseline, without additional medications at 2 consecutive visits after 3 months. Qualified success was defined as the same criteria with additional medications. If these criteria were not met, if additional glaucoma surgery was needed, or if the eye became phtitic, the case was classified as failure. Other outcome measurements were IOP reduction, additional glaucoma medications at the last follow-up, visual acuity, visual field, and complications.

RESULTS

Over a mean follow-up period of 25 +/- 21,91 months, the mean intraocular pressure decreased from 27,98 +/- 6,5 mmHg to 15,2 +/- 5,87 mmHg (mean drop of 45%) at the last visit. Overall success (i.e. with or without medication) was 67.3%. Visual acuity improved or remained unchanged in 52/62 (83,9%) of patients. Eight patients (12,9%) had complications with significant visual loss (at least two Snellen lines worse) and five patients (8,1%) needed further surgery due to complications. No significant outcome predictors could be established.

CONCLUSION

Ahmed and Baerveldt implants are a safe and effective procedure for lowering the IOP in the management of refractory glaucoma.

Fibronectin silanized titanium alloy: a bioinductive and durable coating to enhance fibroblast attachment in vitro

Long term success of percutaneous implants is dependent on soft tissue attachment to prevent infection and epithelial downgrowth, which leads to failure of the implant. Fibronectin coatings are known to enhance fibroblast attachment in vitro, but are subject to desorption from serum protein competition in vivo. This paper quantifies the binding of fibronectin to titanium alloy by silanization and the durability of this attachment when soaked in protein-rich fluid compared with adsorbed fibronectin. The biological activity of fibronectin bound to silanized titanium alloy was confirmed by analyzing cell area, morphology, immunolocalization of focal contacts, and metabolism of dermal fibroblasts. This was compared with both adsorbed fibronectin and uncoated titanium alloy. Silanized titanium alloy bound over twice the amount of fibronectin compared to untreated titanium alloy. On soaking in fetal calf serum there was no significant loss of fibronectin (p = 0.589) from the silanized surface but a significant 44% loss (p = 0.002) from untreated surfaces. Fibroblasts on silanized fibronectin had significantly larger cell areas and more vinculin focal contact markers when compared to untreated surfaces (p < 0.005). The results confirm the durability of silanized fibronectin from protein competition and bioactive effect on fibroblasts.

Identification of peptide antagonists to glycoprotein Ibalpha that selectively inhibit von Willebrand factor dependent platelet aggregation

GPIbalpha is an integral membrane protein of the GPIb-IX-V complex found on the platelet surface that interacts with the A1 domain of von Willebrand factor (vWF-A1). The interaction of GPIbalpha with vWF-A1 under conditions of high shear stress is the first step in platelet-driven thrombus formation. Phage display was used to identify peptide antagonists of the GPIbalpha-vWF-A1 interaction. Two nine amino acid cysteine-constrained phage display libraries were screened against GPIbalpha revealing peptides that formed a consensus sequence. A peptide with sequence most representative of the consensus, designated PS-4, was used as the basis for an optimized library. The optimized selection identified additional GPIbalpha binding peptides with sequences nearly identical to the parent peptide. Surface plasmon resonance of the PS-4 parent and two optimized synthetic peptides, OS-1 and OS-2, determined their equilibrium dissociation GPIbalpha binding constants ( K Ds) of 64, 0.74, and 31 nM, respectively. Isothermal calorimetry corroborated the K D of peptide PS-4 with a resulting affinity value of 68 nM. An ELISA demonstrated that peptides PS-4, OS-1, and OS-2 competitively inhibited the interaction between the vWF-A1 domain and GPIbalpha-Fc in a concentration-dependent manner. All three peptides inhibited GPIbalpha-vWF-mediated platelet aggregation induced under high shear conditions using the platelet function analyzer (PFA-100) with full blockade observed at 150 nM for OS-1. In addition, OS-1 blocked ristocetin-induced platelet agglutination of human platelets in plasma with no influence on platelet aggregation induced by several agonists of alternative platelet aggregation pathways, demonstrating that this peptide specifically disrupted the GPIbalpha-vWF-A1 interaction.

Nutrition-induced catch-up growth increases hypoxia inducible factor 1alpha RNA levels in the growth plate

Although catch-up growth is a well-known phenomenon, the local pathways at the epiphyseal growth plate that govern this process remain poorly understood. To study the mechanisms governing catch-up growth in the growth plate, we subjected prepubertal rats to 10 days of 40% food restriction, followed by a renewal of the regular food supply to induce catch-up growth. The animals were weighed daily, and their humeral length was measured at sacrifice. The proximal tibial epiphyseal growth plates (EGPs) were studied, and findings were compared with EGPs from animals fed ad libitum and animals under food restriction. The gene expression profile in the growth plates was examined using DNA microarrays, and the expression levels of selected genes were validated by real-time polymerase chain reaction. To localize gene expression in different growth plate zones, microdissection was used. Protein levels and localization were examined using immunohistochemistry. We showed that the expression level of 550 genes decreased during food restriction and increased during catch-up growth, starting already one day after refeeding. HIF-1alpha, as well as several of its downstream targets, was found among these genes. Immunohistochemistry showed a similar pattern for HIF-1alpha protein abundance. Additionally, HIF-1alpha mRNA and protein levels were higher in the proliferating than in the hypertrophic zone, and this distribution was unaffected by nutritional status. These findings indicate that nutrition has a profound effect on gene expression level during growth plate growth, and suggest an important role for HIF-1alpha in the growth plate and its response to nutritional manipulation.

Comparison of 4% articaine and 0.5% levobupivacaine/2% lidocaine mixture for sub-Tenon's anaesthesia in phacoemulsification cataract surgery: a randomised controlled trial

BACKGROUND/AIMS

[corrected] The aim of this study was to compare the efficacy and safety of 4% articaine with a mixture containing equal volumes of 2% lidocaine and 0.5% levobupivacaine without hyaluronidase for sub-Tenon's anaesthesia in phacoemulsification cataract surgery.

METHODS

The study was a prospective, randomised double-masked clinical trial of 65 patients allocated to receive either 4% articaine or a mixture containing equal parts of 2% lidocaine and 0.5% levobupivacaine. All patients had pre- and postoperative Hess charting to document ocular motility dysfunction. Ocular and eyelid movements were scored at 2 min intervals from 2 to 10 min after injection of the anaesthetic agent, and at the end of surgery. Complications related to injection, including pain, chemosis and subconjunctival haemorrhage, were recorded. Patients rated pain (none/mild/moderate/severe) during surgery. The operating surgeon masked to the anaesthetic agent assessed proptosis/chemosis at the start of the operation and the degree of ocular akinesia and analgesia at the end of surgery.

RESULTS

The articaine group demonstrated a rapid onset of ocular akinesia with a mean time to readiness for surgery (achieving a score of </=5) of 4.0 min compared with 10 min for the lidocaine/levobupivacaine group (p = 0.001). The effectiveness of block was significantly greater in the articaine group at all points (p<0.01). Surgeons rated ocular akinesia to be superior in the articaine group (p<0.001). Patients and surgeons rated the analgesic effect as comparable in either group. Eyelid scores, subconjunctival haemorrhage and chemosis were comparable in either group. Hess chart was performed on all patients pre- and postoperatively. There was no clinically significant motility disturbance in the articaine group, whereas one patient in the lidocaine/levobupivacaine group developed diplopia with abnormal ocular motility on the Hess chart.

CONCLUSION

Articaine (4%) is a safer and a superior anaesthetic agent than a mixture of 2% lidocaine and 0.5% levobupicaine in achieving ocular akinesia for sub-Tenon's block in phacoemulsification cataract surgery.

Discovery of benzisoxazoles as potent inhibitors of chaperone heat shock protein 90

Heat shock protein 90 (Hsp90) is a molecular chaperone that is responsible for activating many signaling proteins and is a promising target in tumor biology. We have identified small-molecule benzisoxazole derivatives as Hsp90 inhibitors. Crystallographic studies show that these compounds bind in the ATP binding pocket interacting with the Asp93. Structure based optimization led to the identification of potent analogues, such as 13, with good biochemical profiles.

High expression of RelA/p65 is associated with activation of nuclear factor-kappaB-dependent signaling in pancreatic cancer and marks a patient population with poor prognosis

Activation of nuclear factor-kappaB (NF-kappaB) signaling was observed in pancreatic adenocarcinoma cell lines and tumours. However, information on the expression of RelA/p65, the major transcription activating NF-kappaB subunit, in these carcinomas and possible correlations thereof with NF-kappaB activation and patient survival is not available. To provide this missing translational link, we analysed expression of RelA/p65 in 82 pancreatic adenocarcinomas by immunohistochemistry. Moreover, we measured activation of the NF-kappaB pathway in 11 tumours by quantitative PCR for NF-kappaB target genes. We observed strong cytoplasmic or nuclear expression of RelA/p65 in 42 and 37 carcinomas, respectively. High cytoplasmic and nuclear expression of RelA/p65 had negative prognostic impact with 2-year survival rates for patients without cytoplasmic or nuclear RelA/p65 positivity of 41 and 40% and rates for patients with strong cytoplasmic or nuclear RelA/p65 expression of 22 and 20%, respectively. High RelA/p65 expression was correlated to increased expression of NF-kappaB target genes. The observation that high expression of RelA/p65 is correlated to an activation of the NF-kappaB pathway and indicates poor patient survival identifies a patient subgroup that might particularly benefit from NF-kappaB-inhibiting agents in the treatment of pancreatic cancer. Based on our findings, this subgroup could be identified by applying simple immunohistochemical techniques.

CETUFTIRI, a new combination of UFT with leucovorin (LV), irinotecan, and cetuximab as first-line treatment for patients (pts) with unresectable metastatic colorectal cancer (mCRC): Preliminary results from a multicenter phase II trial

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Background: A phase II study (ASCO 2004) established that the combination of UFT (tegafur-uracil) with LV and irinotecan (TEGAFIRI) could be safely administered to pts with unresectable mCRC, with an objective response rate (ORR) of 34% and a median time to progression (TTP) of 5.7 months. We initiated CETUFTIRI, a phase II study, to evaluate the efficacy and tolerability of cetuximab added to TEGAFIRI in chemonaïve pts with unresectable mCRC. Methods: Patients in this single-stage study were aged =18 years, with histologically or cytologically confirmed, bidimensionally measurable mCRC, ECOG performance status 0 or 1, and adequate bone marrow, renal, and hepatic function. EGFR expression was not an inclusion criterion. Treatment consisted of UFT 250 mg/m2/day d1–14, LV 90 mg/day d1–14, and irinotecan 250 mg/m2 d1 every 3 weeks, plus cetuximab 400 mg/m2 week 1 then 250 mg/m2 weekly thereafter. The primary endpoint was ORR and the planned sample size was 61 pts. The study is now closed to accrual. Results: To date, 48 patients are evaluable for safety and 31 are evaluable for efficacy. Patient characteristics (n=48): median age 65 years (range 45–84 years); ECOG PS 0/1: 73/27%; male 65%; tumor sites: colon 69%; rectum 17%; junction 14%; liver metastasis 83%; lung metastasis 46%; other 27%. Adverse events per patient (n=48) after a total of 230 cycles were: grade G3 mucositis 10%; G3/4 neutropenia 10%; G3 nausea/vomiting 8%; G3 asthenia 6%; febrile neutropenia 6%; G3 hypokalemia 6%; G3/4 anemia 4%; G3 diarrhea 2%; acne-like rash G1/2 50% (G3 4%); infusion- related reaction to cetuximab 6%. Two of 31 evaluable pts had a complete response and 11 had a partial response, for an ORR of 42%; 5 pts had stable disease (16%) and 11 pts had progressive disease (35.5%). An independent radiologist review is planned for all 61 pts included up to December 2006. Conclusions: The CETUFTIRI combination seems to have an acceptable toxicity profile with an attractive objective response rate in the first-line treatment of pts with mCRC.

No significant financial relationships to disclose.