Isolated idiopathic chronic pancreatitis associated with a compound heterozygosity for two mutations of the CFTR gene

We report the case of a patient suffering from idiopathic chronic pancreatitis (ICP) and compound heterozygous for mutations G542X and S1235R of the cystic fibrosis transmembrane regulator (CFTR) gene. The patient had normal sweat test and no other clinical sign usually linked with a typical or moderate pathology (bronchiectasis, nasal polyposis, congenital absence of the vas deferens) of the CFTR gene. G542X is a severe mutation, which is usually found in classical cystic fibrosis when associated with other severe mutations. S1235R is a quite rare abnormality recently reported as being potentially pathogenic when combined in trans with a second CF mutation. Our case is quite similar to the only other six patients in the literature in whom only the pancreas is affected and who bear a rare mutation with moderate effect. The history and the clinical features of our patient indicate an unambiguous isolated ICP in which the presence of the S1235R mutation--in trans with regard to G542X--is likely responsible for the ICP phenotype. This case could throw light on some of the as yet poorly known abnormalities of the CFTR gene in the ICP phenotype.     

Stonefish toxin defines an ancient branch of the perforin-like superfamily

The lethal factor in stonefish venom is stonustoxin (SNTX), a heterodimeric cytolytic protein that induces cardiovascular collapse in humans and native predators. Here, using X-ray crystallography, we make the unexpected finding that SNTX is a pore-forming member of an ancient branch of the Membrane Attack Complex-Perforin/Cholesterol-Dependent Cytolysin (MACPF/CDC) superfamily. SNTX comprises two homologous subunits (α and β), each of which comprises an N-terminal pore-forming MACPF/CDC domain, a central focal adhesion-targeting domain, a thioredoxin domain, and a C-terminal tripartite motif family-like PRY SPla and the RYanodine Receptor immune recognition domain. Crucially, the structure reveals that the two MACPF domains are in complex with one another and arranged into a stable early prepore-like assembly. These data provide long sought after near-atomic resolution insights into how MACPF/CDC proteins assemble into prepores on the surface of membranes. Furthermore, our analyses reveal that SNTX-like MACPF/CDCs are distributed throughout eukaryotic life and play a broader, possibly immune-related function outside venom.Human envenoming by the tropical stonefish (Synanceia horrida and related species) results in extreme pain, edema, hypotension, respiratory distress, and on rare occasions, death (1). The lethal factor in stonefish venom is an ∼150-kDa protein termed stonustoxin (SNTX), an unusual example of a vertebrate cytolytic protein complex (2). SNTX is a soluble heterodimeric assembly of two closely related proteins termed SNTX-α and -β that share sequence identity of ∼50% (3). With the exception of a C-terminal PRY SPla and the RYanodine Receptor (PRYSPRY) domain in each protein (4), SNTX shares no obvious sequence similarity to any structurally or functionally characterized molecule. SNTX induces species-specific hemolytic activity (2) by an apparent pore-forming mechanism (5). It induces platelet aggregation (6), and like the closely related Trachynilysin (from Synanceia trachynis), SNTX exhibits activity suggesting that it may function as a neurotoxin (7, 8).Because eukaryote pore-forming toxins are relatively rare, we reasoned that SNTX might represent a new exemplar of a vertebrate pore-forming protein. Previous studies had shown that it was possible to purify and crystallize SNTX (9); however, no structure has been reported to date. Accordingly, to address the structural basis for SNTX activity, we determined its X-ray crystal structure.     

X-ray crystal structure of the streptococcal specific phage lysin PlyC

Bacteriophages deploy lysins that degrade the bacterial cell wall and facilitate virus egress from the host. When applied exogenously, these enzymes destroy susceptible microbes and, accordingly, have potential as therapeutic agents. The most potent lysin identified to date is PlyC, an enzyme assembled from two components (PlyCA and PlyCB) that is specific for streptococcal species. Here the structure of the PlyC holoenzyme reveals that a single PlyCA moiety is tethered to a ring-shaped assembly of eight PlyCB molecules. Structure-guided mutagenesis reveals that the bacterial cell wall binding is achieved through a cleft on PlyCB. Unexpectedly, our structural data reveal that PlyCA contains a glycoside hydrolase domain in addition to the previously recognized cysteine, histidine-dependent amidohydrolases/peptidases catalytic domain. The presence of eight cell wall-binding domains together with two catalytic domains may explain the extraordinary potency of the PlyC holoenyzme toward target bacteria.     

Vitamin D3 Supplementation Alleviates Left Ventricular Dysfunction in a Mouse Model of Diet-Induced Type 2 Diabetes: Potential Involvement of Cardiac Lipotoxicity Modulation

Cardiovascular Drugs and Therapy - To evaluate the effectiveness of vitamin D3 supplementation, in secondary prevention, on cardiac remodeling and function, as well as lipid profile, in a mouse...     

Concurrent cisplatin/etoposide plus 3D-conformal radiotherapy followed by surgery for stage IIB (superior sulcus T3N0)/III non-small cell lung cancer yields a high rate of pathological complete response

Introduction: Optimal preoperative treatment of stage IIB (Pancoast)/III non-small cell lung cancer (NSCLC) remains undetermined and a subject of controversy. The goal of our study is to confirm feasibility and pathological response rates after induction chemoradiation (CRT) in our community-based treatment center. Patients and methods: Patients were selected according to functional and resectability criteria. Induction treatment comprised 3D conformal 4500 cGy radiotherapy delivered to the primary tumor and pathologic hilar and/or mediastinal lymph nodes on CT scan with an extra-margin of 1–1.5 cm. Concurrent chemotherapy regimen was cisplatinum 20 mg/m² d1–d5 and etoposide 50 mg/m² d1–d5, d1–5 d29–33. Within 3–4 weeks after CRT completion, operability was re-assessed accordingly. Surgery was performed 4–6 weeks after CRT completion in patients (pts) deemed resectable. Inoperable pts were referred for a 20–25 Gy boost ±1 extra-cycle of cisplatinum + etoposide. Results: From 1996 to 2005, 107 pts were initially selected for treatment and received induction chemoradiation (stage IIB-Pancoast 18, IIIA 58 and IIIB 31, squamous cell carcinoma 48%, adenocarcinoma 44%, large-cell undifferentiated carcinoma 14%). After preoperative evaluation, 72 pts (67%) had a thoracotomy (pneumonectomy 21, lobectomy 45, bilobectomy 5) and all but one (unresectable tumor) had a macroscopic complete resection. During the 3-month postoperative time, five patients (6.9%) died, four after pneumonectomy (right 3, left 1). The analysis of tumoral samples showed a pathological complete response rate or microscopic residual foci of 39.5%. Median follow-up time was 22.3 months (survivors: 36.8 months), 2-year and 3-year overall survival rates were 55% and 40%, respectively (median = 26.7 months) for all the intention-to-treat population (n = 107), 62% and 51% (median = 36.5 months) for 71 resected pts, 41% and 16% for 36 non-resected pts (median = 19.1 months). On multivariate analysis, surgical resection and tumoral necrosis >50% (or pathological complete response) were the most pertinent predictive factors of the risk of death (hazard ratio = 0.50 and 0.48, p = 0.006 and 0.038, respectively). Conclusion: Surgery was feasible after induction chemoradiation, particularly lobectomy in PS 0–1, stage IIB (Pancoast)/III NSCLC pts but pneumonectomy carries a high risk of postoperative death (particularly, right pneumonectomy). Pathological response to induction chemoradiation was complete in 39.5% of patients and was a significant predictive factor of overall survival.     

Combination radiotherapy and chemotherapy in cancer of the pancreas. Review of the literature and prospects

Overall prognosis of pancreatic adenocarcinoma is still very poor with median survival around 10 months after radical surgery in operable patients, or after full-dose radiation therapy in non-surgical candidates. In metastatic disease, multidrug chemotherapy regimens give a response rate of around 30% with median survival of 10 months. Random trials conducted by the GITSG in inoperable cases have shown improved results for chemoradiation with 5-FU for radiotherapy alone and a doubling of median survival with a 1-year survival of 40% vs 10%. Incorporation of Adriamycin in these combined modality protocols does not improve the results in terms of survival. Chemoradiation also shows improved results compared with chemotherapy alone. In patients amenable to radical surgery, adjuvant post-operative treatment with chemoradiation gave superior results over surgery alone with a doubling of median survival and a significant improvement of a two-year survival rate (42% versus 15%). Intra-operative radiation therapy leads to better local control but without a significant improvement in survival. With a better understanding of radio-chemotherapy interactions and mechanisms of radiosensitization through continuous infusion of fluorouracil and/or cisplatinum, these encouraging results should be confirmed within the next few years.