Proactive screening in Israel identifies alarming prevalence of malnutrition among hospitalized patients--action is needed

ObjectiveMalnourished patients suffer from higher morbidity and mortality rates than well-nourished patients do. However, few studies have controlled the outcomes for the underlying illnesses. Our aim was to determine the prevalence of malnutrition among patients admitted to the internal medicine ward and to determine whether malnutrition is an independent risk factor for adverse outcomes in these settings.MethodsConsecutive patients screened for malnutrition with the MUST (Malnutrition Universal Screening Tool), admitted to an internal medicine department, were included in this study. Demographic data, background disease, laboratory results, length of stay, and mortality rates were retrieved from the computerized file and Charlson Comorbidity Index (CCI) was calculated. Univariate and multivariate analyses were used to check for the association of malnutrition and outcome measures.ResultsOne thousand consecutive patients were included in the study. Mean age was 67.6 y; 25.4% of patients were found to be at high risk for malnutrition. Patients at high risk for malnutrition had significantly longer length of stay and mortality rates than well-nourished patients (9.7 d versus 6.2 d and 19.3% versus 3.2%; accordingly [P < 0.001]). On multivariate analyses, increased mortality was found to be associated with a high risk for malnutrition as well as pneumonia, acute myocardial infarction, acute renal failure, or shock on admission and a high CCI score.ConclusionThe prevalence of malnutrition among hospitalized patients, as measured by the MUST score, is common. Malnutrition is prevalent and represents an independent and significant risk factor for in-hospital mortality and increased length of stay in patients admitted to the internal medicine ward.     

Pain sensitivity is inversely related to regional grey matter density in the brain

Pain is a highly personal experience that varies substantially among individuals. In search of an anatomical correlate of pain sensitivity, we used voxel-based morphometry to investigate the relationship between grey matter density across the whole brain and interindividual differences in pain sensitivity in 116 healthy volunteers (62 women, 54 men). Structural magnetic resonance imaging (MRI) and psychophysical data from 10 previous functional MRI studies were used. Age, sex, unpleasantness ratings, scanner sequence, and sensory testing location were added to the model as covariates. Regression analysis of grey matter density across the whole brain and thermal pain intensity ratings at 49 °C revealed a significant inverse relationship between pain sensitivity and grey matter density in bilateral regions of the posterior cingulate cortex, precuneus, intraparietal sulcus, and inferior parietal lobule. Unilateral regions of the left primary somatosensory cortex also exhibited this inverse relationship. No regions showed a positive relationship to pain sensitivity. These structural variations occurred in areas associated with the default mode network, attentional direction and shifting, as well as somatosensory processing. These findings underscore the potential importance of processes related to default mode thought and attention in shaping individual differences in pain sensitivity and indicate that pain sensitivity can potentially be predicted on the basis of brain structure.     

Structural basis for KIT receptor tyrosine kinase inhibition by antibodies targeting the D4 membrane-proximal region

Somatic oncogenic mutations in the receptor tyrosine kinase KIT function as major drivers of gastrointestinal stromal tumors and a subset of acute myeloid leukemia, melanoma, and other cancers. Although treatment of these cancers with tyrosine kinase inhibitors shows dramatic responses and durable disease control, drug resistance followed by clinical progression of disease eventually occurs in virtually all patients. In this report, we describe inhibitory KIT antibodies that bind to the membrane-proximal Ig-like D4 of KIT with significant overlap with an epitope in D4 that mediates homotypic interactions essential for KIT activation. Crystal structures of the anti-KIT antibody in complex with KIT D4 and D5 allowed design of affinity-matured libraries that were used to isolate variants with increased affinity and efficacy. Isolated antibodies showed KIT inhibition together with suppression of cell proliferation driven by ligand-stimulated WT or constitutively activated oncogenic KIT mutant. These antibodies represent a unique therapeutic approach and a step toward the development of “naked” or toxin-conjugated KIT antibodies for the treatment of KIT-driven cancers.The receptor tyrosine kinase (RTK) KIT is a transmembrane protein that plays crucial roles in mediating diverse cellular processes including cell differentiation, proliferation, and cell survival, among other activities. These processes occur through activation of KIT upon binding by stem cell factor (SCF), a ligand found in membrane-anchored and soluble forms (1, 2) in a variety of cell types, including hematopoietic stem cells, germ cells, vascular endothelial cells, and the mesenchymal cells with uniquely neuromuscular differentiation known as the interstitial cells of Cajal (3, 4). KIT belongs to the type III subfamily of RTKs (5), a family composed of an extracellular region that includes five Ig-like domains (designated D1–D5), a single transmembrane domain (TM), a juxtamembrane region (JM), a tyrosine kinase domain split by a kinase insert, and a C-terminal tail (6) (Fig. 1A).Open in a separate windowFig. 1.Structure of the Fab19–KIT_D4-5 complex. (A) Schematic representation of WT KIT as well as the KIT_D4-5 fragment that was used in this study. Glu381 and Arg386, residues important for KIT activation, are marked on KIT_D4-5 fragment. D1 to D5 are Ig-like domains 1 to 5 respectively. JM, juxtamembrane; KI, kinase insert; PTK, protein tyrosine kinase domain; TM, transmembrane. (B) Surface representation of Fab19–KIT_D4-5 complex. (Left) View following 90° rotation along the shown axis. D4 and D5 of KIT are colored with orange and pink, and heavy and light chains of Fab19 with blue and green, respectively. The regions of interactions between Fab19 and KIT_D4-5 are visualized in “open-book” format for D4 (C) and Fab (D). The buried surface area on the D4 side is shown in red in C and is in the same scale as in B. The interactions between Fab19 and D4 are mediated by CDR loops and surrounding residues. The buried interface surface of the Fab19 is color coded by CDR: H1, cyan; H2, magenta; H3, gray; L2, bright green; L3, yellow (D). Fab19 in D is enlarged compared with images in B and C.Based on the determination of the crystal structure of the complete extracellular region of KIT before and after ligand stimulation (7), and the tyrosine kinase domain (8, 9), a mechanism has been proposed whereby activation of KIT is initiated through receptor dimerization (10). Dimerization of the KIT ectodomain is ligand-driven and initiated through high-affinity binding of an SCF dimer to the membrane distal Ig-like domains (D1–D3) of the receptor (11, 12). Cross-linking of the membrane distal Ig-like domains with their ligand dramatically increases local concentration of the membrane-proximal (D4 and D5) and TMs to enable homotypic contacts by weak D4–D4 and D5–D5 interactions between neighboring KIT molecules. These homotypic associations promote conformational rearrangements that permit correct association between neighboring cytoplasmic regions of KIT dimers resulting in autophosphorylation, tyrosine kinase stimulation, recruitment of signaling proteins, and cell signaling.Dysregulation of KIT, by a variety of different somatic as well as rare germ-line mutations, has been associated with numerous hematopoietic and other cancers, including gastrointestinal stromal tumors (GIST), a subset of melanomas, systemic mastocytosis, and acute myeloid leukemia. Most reoccurring activating mutations map to the cytoplasmic JM region (exon 11) and to the membrane-proximal Ig-like domain D5 (exon 9) of the extracellular region (13, 14). Currently, initial treatment for patients with GIST involves the small-molecule kinase inhibitor Gleevec (imatinib), which can efficiently block kinase activity of JM and D5 mutants of KIT. Unfortunately, most patients with GIST develop resistance to the drug within 2 y of treatment by acquiring additional mutations usually mapped to exons 13 and 14 (V654A and V670I, respectively). Patients resistant to Gleevec are usually treated with the kinase inhibitor Sutent (sunitinib), which can more efficiently inhibit WT KIT protein as well as many of the mutations that confer imatinib resistance. In addition to Gleevec-resistant mutations in exons 13 and 14, kinase domain mutants (exon 17) that are resistant to Gleevec and Sutent are also seen in patients with GIST (15).Several mAbs targeting RTKs have shown promising results as anticancer therapies, including mAbs against members of the EGFR family of RTKs, which were approved for clinical use, including cetuximab and panitumumab (anti-EGFR mAbs), as well as trastuzumab and pertuzumab (anti-ErbB2 mAbs) (16, 17). Antibodies can be highly specific for their targets, and therefore off-target side effects are reduced compared with small-molecule kinase inhibitors. Specific targeting of oncogenic RTKs by inhibitory mAbs may allow the resistance that frequently occurs in patients treated with kinase inhibitors to be surmounted.We have shown previously that homotypic interactions between the membrane-proximal domains of KIT (D4 and D5) are critical for receptor activation and that disruption of the D4–D4 interface strongly compromises receptor activation (7). As KIT oncogenic mutants located in D5 are dependent on homotypic contacts between neighboring ectodomains, it is reasonable to expect that activation of these mutants could be inhibited by monoclonal antibodies directed against KIT domains D4 or D5. Here, anti-KIT antibodies were isolated from a naive, phage-displayed synthetic antibody library. Crystal structures of a fragment antigen-binding (Fab) in complex with KIT membrane-proximal domains D4 and D5 (KIT_D4-5) revealed binding to D4 that overlapped significantly with an epitope required for homotypic interactions essential for SCF-dependent KIT activation. Furthermore, information obtained from the structure of antibody in complex with KIT was applied to guide the design of affinity maturation libraries, enabling isolation of antibody variants with increased binding affinity equating to increased efficacy. These antibodies were capable of efficient inhibition of KIT activity that led to suppression of cell proliferation and provide a potentially unique therapeutic approach for the treatment of tumors driven by WT or aberrantly activated KIT mutants.     

Expression of the homeostasis-related markers,maspin, heat shock proteins 70 & 90, glutathione S-transferase,aquaporin 5 and NF-kB in young and old labial and palatal salivary glands

Intraoral salivary glands undergo remarkable age-related morphologic changes. This study investigated the expression of a panel of molecular markers known for cellular homeostatic activity, dependent on age and location of the salivary glands. Samples taken from healthy subjects were classified according to age (“young” < 45 years, n = 51, and “old” ≥ 60 years, n = 45) and location (lip, n = 47 and palate, n = 49). They were immunohistochemically stained for mammary serine protease inhibitor (maspin), heat shock protein (HSP)70, HSP90, glutathione S-transferase (GST), aquaporine5 (AQP5), and nuclear factor kappa-B (NF-κB) for assessment of their expression in acini and ducts, and in cytoplasmic and nuclear compartments. Results were expressed as the mean percentage of positively stained component per age group, gland location and type of cell and cellular compartment. Statistical analysis was performed by two-way ANOVA and crosstabs. The expression of maspin was lower in the old group in both the palatal and labial glands (acini and ducts, cytoplasm and nuclei) compared to the young group (p < 0.05). In both age groups, when compared to labial glands, palatal glands exhibited higher expression of HSP70 (p < 0.05) and lower expression of AQP5 (p < 0.001) and NF-κB (p = 0.018). Collectively, the low expression of factors capable of preserving cellular homeostasis (i.e., maspin and AQP5) vis-à-vis a high expression of factors that are also related to cell survival (i.e., HSPs) that was demonstrated in the old palatal glands may point to their high vulnerability to undergo selective phenotypic changes.     

The albino mutation of tyrosinase alters ocular angiogenic responsiveness

We have observed substantial differences in angiogenic responsiveness in mice and have mapped the genetic loci responsible for these differences. We have found that the albino mutation is one of the loci responsible for such differences. Using B6.A consomic strains, we determined that chromosome 7 bears a locus that inhibits VEGF-induced corneal neovascularization. F2 crosses between B6.A<Chromosome 7> consomic mice and C57BL/6J parents along with AXB and BXA recombinant inbred strains demonstrated highest linkage near the tyrosinase gene. This region was named AngVq4. Congenic animals confirmed this locus, but could not demonstrate that the classical tyrosinase albino (c) mutation was causative because of the existence of additional linked loci in the congenic region. However, in 1970, a second tyrosinase albino mutation (c-2J) arose in the C57BL/6J background at Jackson Labs. Testing this strain (C57BL/6J<c-2J>) demonstrated that the albino mutation is sufficient to completely explain the alteration in angiogenic response that we observed in congenic animals. Thus, we conclude that the classical tyrosinase mutation is responsible for AngVq4. In contrast to the cornea, where pigmented animals exhibit increased angiogenic responsiveness, iris neovascularization was inhibited in pigmented animals. These results may partially explain increased aggressiveness in amelanotic melanoma, as well as ethnic differences in diabetic retinopathy and macular degeneration.     

Pterygium surgery: fibrin glue versus Vicryl sutures for conjunctival closure

PURPOSE: To compare the short-term results of conjunctival closure in pterygium surgery using fibrin adhesive versus Vicryl sutures with respect to operative time, postoperative ocular signs and symptoms, and overall patient satisfaction. METHODS: A comparative prospective randomized clinical trial was performed in 65 patients (65 eyes) with primary nasal pterygium. Surgery in all patients consisted of the bare sclera technique combined with intraoperative mitomycin C. Patients were randomized to undergo conjunctival closure with a fibrin tissue adhesive (Quixil; n = 39) or 8-0 Vicryl absorbable interrupted sutures (n = 26). Clinical assessment was performed on days 1, 3, 10, and 21 after surgery. Patients completed a questionnaire at each follow-up visit, grading pain, discomfort, and satisfaction with the procedure. The groups were compared for operative time, ocular signs and symptoms, and overall satisfaction. RESULTS: Average operative time was 16 minutes (range, 14-16 minutes) in the fibrin glue group and 20 minutes (range, 20-29 minutes) in the Vicryl suture group (P < 0.05). Significantly less pain, photophobia, foreign body sensation, irritation, epiphora, itching, local hyperemia, conjunctival chemosis, and dry eye were noted in the subjects treated with glue than in controls (P < 0.05). There were no complications during the 3-week follow-up period in the glue-treated patients. One of the patients in the suture group had a medically treatable corneal delle. CONCLUSION: The use of fibrin glue in pterygium surgery significantly reduces operative time and patient symptoms, pain, and discomfort. A longer follow-up is needed to evaluate the influence of fibrin glue on rate of recurrence and long-term complications.     

Heparanase promotes growth, angiogenesis and survival of primary breast tumors

Despite great strides toward diagnosis and therapy, breast cancer remains a most threatening disease in its incidence, morbidity and mortality; therefore, additional knowledge regarding the molecular mechanisms contributing to breast cancer progression, as well as new targets for drug discovery are highly needed. Heparanase is the predominant enzyme involved in cleavage of heparan sulfate, the main polysaccharide component of the extracellular matrix. Experimental and clinical data indicate that heparanase plays important roles in cancer metastasis and angiogenesis. In breast carcinoma patients, heparanase expression correlates with the metastatic potential of the tumor. The present study was undertaken to investigate the role of heparanase in local growth and angiogenesis of primary breast tumors. MCF-7 breast carcinoma cells were stable transfected with the human heparanase (H-hpa) cDNA, or empty vector (mock), and injected into the mammary pad of nude mice. MRI was applied to monitor progression of tumor growth and angiogenesis. We demonstrate that tumors produced by cells overexpressing heparanase grew faster and were 7-fold larger than tumors produced by mock transfected cells. This enhanced growth was accompanied by increased tumor vascularization and a higher degree of vessel maturation. Histological examination ascribed the differences in tumor growth to heparanase-stimulated cell proliferation and survival. In-vitro experiments reinforced heparanase role as a survival factor under stress conditions. Moreover, H-hpa tumor cells infiltrate into the adjacent stroma, promoting formation of highly vascularized fibrous bands. Our results emphasize the significance and clarify the involvement of heparanase in primary breast cancer progression by generating a supportive microenvironment that promotes tumor growth, angiogenesis and survival.     

Progesterone receptor expression in human decidua and fetal membranes before and after contractions: possible mechanism for functional progesterone withdrawal

In humans, progesterone levels are sustained before the onset of labour. Therefore, the mechanism for parturition that has been proposed for humans is 'functional' progesterone withdrawal. Immunohistochemical staining for the progesterone receptor (PR) was positive in the decidua with a decline after contractions began. Western blot analysis revealed a number of PR isoforms expressed in the decidua, with the PR-B form being dominant. After contractions began, all PR isoforms decreased sharply. PR-B and PR-A decreased by 85.8% +/- 6.7 and 78.2% +/- 7.1, respectively (P < 0.001). Incubation of decidua with Prostaglandin F2alpha 1.0 microg/ml decreased the expression of all forms of PR isoforms. PR-B was reduced by 64% +/- 6.09 (P < 0.01); PR-A was reduced by 77% +/- 5.9 (P < 0.05), while PR-C was reduced by 80% +/- 7.24 (P < 0.05). Progesterone (80 microg/ml) increased the PR-B, PR-C the 45 and 36 kDa isoforms to 150% +/- 7.89, 210% +/- 12.4, 270% +/- 9.7 and 216% +/- 13.5, respectively (P < 0.05). In immunohistochemical studies, the PR was not identified in the amnion or in the chorion, regardless of the presence or absence of contractions. Western blot analysis demonstrated that PR-C (60 kDa) and the 36 kDa isoforms were dominant in the amnion. After contractions began, PR-A decreased significantly by 61.9% +/- 7.1 (P < 0.001).