Carbohydrate binding modules enhance cellulose enzymatic hydrolysis by increasing access of cellulases to the substrate.

Plant biomass is a low-cost and abundant source of carbohydrates for production of fuels, "green" chemicals and materials. Currently, biochemical conversion of the biomass into sugars via enzymatic hydrolysis is the most viable technology. Here, the role of carbohydrate binding modules (CBMs) in the disruption of insoluble polysaccharide structures and their capacity to enhance cellulase-promoted lignocellulosic biomass hydrolysis was investigated. We show that CBM addition promotes generation of additional reducing ends in the insoluble substrate by cellulases. On the contrary, bovine serum albumin (BSA), widely used in prevention of a non-specific protein binding, causes an increase in soluble reducing-end production, when applied jointly with cellulases. We demonstrate that binding of CBMs to cellulose is non-homogeneous, irreversible and leads to its amorphisation. Our results also reveal effects of CBM-promoted amorphogenesis on cellulose hydrolysis by cellulases.

On the subtle tuneability of cellulose hydrogels: implications for binding of biomolecules demonstrated for CBM 1.

Cellulose-based hydrogel materials prepared by regeneration from cellulose solutions in ionic liquids, or ionic liquid containing solvent mixtures (organic electrolyte solutions), are becoming widely used in a range of applications from tissue scaffolds to membrane ionic diodes. In all such applications knowledge of the nature of the hydrogel with regards to porosity (pore size and tortuosity) and material structure and surface properties (crystallinity and hydrophobicity) is critical. Here we report significant changes in hydrogel properties, based on the choice of cellulose raw material (α- or bacterial cellulose - with differing degree of polymerization) and regeneration solvent (methanol or water). Focus is on bioaffinity applications, but the findings have wide ramifications, including in biomedical applications and cellulose saccharification. Specifically, we report that the choice of cellulose and regeneration solvent influences the surface area accessible to a family 1 carbohydrate-binding module (CBM), CBM affinity for the cellulose material, and rate of migration through the hydrogel. By regenerating bacterial cellulose in water, a maximum accessible surface area of 33 m2 g-1 was achieved. However, the highest CBM migration rate, 1.76 µm2 min-1, was attained by regenerating α-cellulose in methanol, which also resulted in the maximum affinity of the biomolecule for the material. Thus, it is clear that if regenerated cellulose hydrogels are to be used as support materials in bioaffinity (or other) applications, a balance between accessible surface area and affinity, or migration rate, must be achieved.

Mucosal tolerance of the hookworm Ancylostoma caninum in the gut of naturally infected wild dogs.

Ancylostoma caninum is a very pathogenic hookworm that locates in the small intestine of the dog and other canid species. The mucosal response of wild dogs naturally infected with A. caninum was investigated in this study. In spite of diffuse infiltrations of the mucosa with CD3+ , CD4+ , CD8+ , CD11c+ , CD21+ or MHC class II antigen cells, no focal infiltrations with any of these cell phenotypes were observed around the buccal capsule or the body of the feeding worms. Very few or no apoptotic cells could be detected around the worms fixed into the mucosa but they were detected on the tip of villi and in the superficial layer of cellular debris and proteinaceous exudate that covers the mucosa. Muc5AC, a mucine associated with expulsion of gut worms (Trichuris muris) was expressed extremely weakly or was not expressed at all in the intestine of the wild dogs infected with A. caninum. Our data show that individual specimens of A. caninum can reside for some time in the mucosa of the gut of dogs undetected and most likely unaffected by the effectors of the local immune response.

Acute inflammation with induction of anaphylatoxin C5a and terminal complement complex C5b-9 associated with multiple intra-articular injections of hylan G-F 20: a case report.

OBJECTIVE: The purpose of this case report was to investigate local immune mechanisms present during an acute inflammatory flare initiated by viscosupplementation with hylan G-F 20 in a patient with osteoarthritis (OA) and past meniscectomy. EXPERIMENTAL DESIGN: A patient with a history of bilateral OA and partial left knee meniscectomy, who had received three injections of hylan G-F 20, was diagnosed with an acute flare reaction in the left knee. Her chart was evaluated for clinical, radiological, and laboratory findings and for clinical follow-up. Histopathological synovial examination and real-time polymerase chain reaction (RT-PCR) for genes with major roles in local inflammation and enzyme-linked immunosorbent assays (ELISAs) for markers of complement activation and cytokines were performed. To study the impact of the inflammatory and immune features we compared the case patient with groups of three representative OA and three rheumatoid arthritis (RA) patients. RESULTS: The patient exhibited evidence of highly increased acute phase reactant C-reactive protein (CRP) in the blood. The pathological examination of the synovial membrane identified abundant fibrinous exudate with numerous particles of hyaluronan surrounded by a dense infiltrate of neutrophils and eosinophils. The synovium had moderate hypertrophy and sclerosis as well as an inflammatory infiltrate predominantly composed of T lymphocytes and macrophages with scattered perivascular eosinophils and neutrophils. Immunoperoxidase staining identified numerous deposits of C5b-9 in the fibrinous exudates and the synovial membrane of the patient. Similar findings were observed in the RA patients, whereas deposits were rare in OA synovial samples. In addition, both anaphylatoxin C5a and the terminal complement complex C5b-9 were present at high levels, comparable to those in RA patients. The levels of mRNA for interleukin-1 beta (IL-1ß), IL-6, and the neutrophil marker myeloperoxidase (MPO) were markedly increased compared to those in the RA and OA patients. CONCLUSIONS: This present study is indicative of a pseudo-septic acute inflammatory reaction in response to local accumulation of hylan G-F 20 with the activation of complement and local invasion of pro-inflammatory cells.

Befriending patients with medication-resistant schizophrenia: can psychotic symptoms predict treatment response?

OBJECTIVES: Supportive interventions are used in schizophrenia, but little research has been conducted into whether any baseline variable predicts treatment response. The aim of this study was to establish if baseline delusions or hallucinations are associated with changes in overall symptoms in patients who received a befriending intervention. DESIGN: The sample consisted of 44 patients with schizophrenia. These patients comprised the befriending arm of a multicentre randomized controlled trial which compared the efficacy of using CBT against befriending as an adjunct to routine care for patients with medication-resistant schizophrenia. METHODS: Scores for auditory hallucinations and delusions relating to persecution or control were entered into two regression models. The dependent variables were change in overall symptoms (1) between baseline and end of the intervention, and (2) between baseline and 9 months post-intervention. RESULTS: Baseline delusions predicted a good response and auditory hallucinations predicted a poor response at 9 months. CONCLUSIONS: Baseline psychotic symptoms strongly predicted outcome in this sample. The finding that hallucinations predicted a poor outcome is consistent with previous research. These results may help to determine which patients would benefit from supportive interventions.

Understanding solid/solid organic reactions.

The concept of an organic reaction between two macroscopic solid particles is investigated. Thus, we study several reactions that have been recently reported to proceed "in the solid phase" and clearly show that, in most cases, grinding the two solid reactants together results in the formation of a liquid phase. This is true both for catalytic transformations (e.g., aldol condensations and oligomerization of benzylic compounds) and for noncatalytic reactions (Baeyer-Villiger oxidations, oxidative coupling of naphthols using iron chloride, condensation of amines and aldehydes to form azomethines, homo-etherification of benzylic alcohols using p-toluenesulfonic acid, and nuclear aromatic bromination with NBS). This liquefaction implies the existence of a eutectic mixture with T(fusion) below ambient temperature (although both reagents have higher than ambient melting points). In cases where heating is required, it is again clear that a phase change (from solid to liquid) occurs, explaining the observed reaction kinetics. On the basis of 19 experimental examples, we discuss the possibility of solid-phase organic reactions and the implications of these findings to the reaction between two solid reagents. A general description of such reactive systems is proposed, based on a consideration of the potential for eutectic (or peritectic) formation between the constituents of the liquid phases that arise during the process of mechanical mixing of the solid reagents and products.

Working memory capacity and strategy use.

In this study, we examine the role of strategy use in working memory (WM) tasks by providing short-term memory (STM) task strategy training to participants. In Experiment 1, the participants received four sessions of training to use a story-formation (i.e., chaining) strategy. There were substantial improvements from pretest to posttest (after training) in terms of both STM and WM task performance. Experiment 2 demonstrated that WM task improvement did not occur for control participants, who were given the same amount of practice but were not provided with strategy instructions. An assessment of participants' strategy use on the STM task before training indicated that more strategic participants displayed better WM task performance and better verbal skills. These results support our hypothesis that strategy use influences performance on WM tasks.

Effects of water salinity on acid-base balance in decapod crustaceans.

Extracellular acid-base balance in decapod crustaceans is influenced by water salinity, although the nature of this relationship is unclear. In euryhaline crabs, a decrease in salinity results in a metabolic alkalosis in the haemolymph and an increase in salinity results in a metabolic acidosis. Alterations in acid-base status by external changes in salinity are thought to be secondary to the adjustments required for ionic and osmotic regulation. In the present study, acid-base adjustments in the haemolymph of Eriocheir sinensis after transfer to 30 % sea water accompanied alterations in muscle pH and [HCO(3)(-)], as an initial acidosis coincided with an alkalosis in the leg muscle. By 48 h transfer, haemolymph pH increased as muscle pH and HCO(3)(-) declined. Haemolymph [Cl(-)] decreased significantly 3 h after transfer to a new steady state but haemolymph [Na(+)] and muscle [Na(+)] and [Cl(-)] remained unchanged. Muscle free amino acid concentration increased twofold 6 h after transfer, followed by a 2.5-fold increase in the haemolymph after 24 h. In contrast, 30 % sea water had no effect on haemolymph acid-base adjustments in the osmoconforming crab, Necora puber, which lacks ion and osmo-regulatory mechansims. Collectively these observations support the view that salinity-induced alterations in acid-base status are caused by adjustments consistent with cell volume regulation.

Recent advances in solventless organic reactions: towards benign synthesis with remarkable versatility.

A paradigm shift away from using solvents in organic synthesis as solventless reactions can lead to improved outcomes, and more benign synthetic procedures, in for example aldol condensation reactions, sequential aldol and Michael addition reactions en route to Kröhnke type pyridines, reactions leading to 3-carboxycoumarins, benzylidenes, 4-aryl-1,4-dihydropyridines and 2-aryl-1,2,3,4-tetrahydroquinazolines, and oligomerisation reactions for the synthesis of cavitands; kinetic considerations for the reaction of two solids can only be explained if a eutectic melt is formed during the reaction.

A randomized controlled trial of cognitive-behavioral therapy for persistent symptoms in schizophrenia resistant to medication.

BACKGROUND: Research evidence supports the efficacy of cognitive-behavioral therapy in the treatment of drug-refractory positive symptoms of schizophrenia. Although the cumulative evidence is strong, early controlled trials showed methodological limitations. METHODS: A randomized controlled design was used to compare the efficacy of manualized cognitive-behavioral therapy developed particularly for schizophrenia with that of a nonspecific befriending control intervention. Both interventions were delivered by 2 experienced nurses who received regular supervision. Patients were assessed by blind raters at baseline, after treatment (lasting up to 9 months), and at a 9-month follow-up evaluation. Patients continued to receive routine care throughout the study. An assessor blind to the patients' treatment groups rated the technical quality of audiotaped sessions chosen at random. Analysis was by intention to treat. RESULTS: Ninety patients received a mean of 19 individual treatment sessions over 9 months, with no significant between-group differences in treatment duration. Both interventions resulted in significant reductions in positive and negative symptoms and depression. At the 9-month follow-up evaluation, patients who had received cognitive therapy continued to improve, while those in the befriending group did not. These results were not attributable to changes in prescribed medication. CONCLUSION: Cognitive-behavioral therapy is effective in treating negative as well as positive symptoms in schizophrenia resistant to standard antipsychotic drugs, with its efficacy sustained over 9 months of follow-up.

Violence as a public health emergency.

Violence threatens or denies not only the health of those who are directly affected but diminishes the whole human process. Neither the violent acts themselves, nor the repercussions of these tragedies, are limited to one geographic or social setting, and it is not just the frequency of violent actions that threatens the health of the nation. It is the ripple effect that occurs from each of these incidents that affects everyone. This article discusses the problem of national violence in the United States and examines preventive programs.

A community medicine project involving an educational session in sexually transmitted diseases for high school students.

The University of South Dakota School of Medicine requires that students undertake a Community Medicine project of their choice as part of the Family Medicine course in the third year of medical school. One of these projects consisted of a presentation given to a high school class in Sioux Falls, South Dakota, on sexually transmitted diseases. The effectiveness of the presentation in increasing the students' knowledge on this subject was measured by a pretest and posttest multiple choice examination. The students' knowledge was clearly increased by the presentation.

TLiSA1 (PTA1) activation antigen implicated in T cell differentiation and platelet activation is a member of the immunoglobulin superfamily exhibiting distinctive regulation of expression.

T lineage-specific activation antigen 1 (TLiSA1) antigen was initially described as a T lineage-specific activation antigen involved in the differentiation of human cytotoxic T cells. Subsequently, the antigen was identified on platelets and was shown to be involved in platelet activation, hence it was renamed platelet and T cell antigen 1 (PTA1), although identity between the two antigens was not established. In the present study we have cloned the cDNA encoding TLiSA1 from Jurkat cells and show it to be a novel member of the immunoglobulin superfamily with the unusual structure of two V domains only. Identity between TLiSA1 and platelet PTA1 is established by immunological criteria, by internal peptide sequences obtained from the purified platelet glycoprotein and by sequencing the platelet transcript after reverse transcriptase-polymerase chain reaction. In Jurkat cells, TLiSA1/PTA1 mRNA and surface protein expression is greatly stimulated by treatment of the cells with phorbol ester, but the T cell proliferative signal of phorbol ester and ionophore combined greatly reduces or abrogates this response, and this suppressive effect of the ionophore is not reversed by incorporating FK506 to inhibit calcineurin. Together with the known signaling role of PTA1, these data substantiate the notion that this molecule is implicated in T cell differentiation, perhaps by engagement of an adhesive ligand.

Complete genome sequence of the methanogenic archaeon, Methanococcus jannaschii.

The complete 1.66-megabase pair genome sequence of an autotrophic archaeon, Methanococcus jannaschii, and its 58- and 16-kilobase pair extrachromosomal elements have been determined by whole-genome random sequencing. A total of 1738 predicted protein-coding genes were identified; however, only a minority of these (38 percent) could be assigned a putative cellular role with high confidence. Although the majority of genes related to energy production, cell division, and metabolism in M. jannaschii are most similar to those found in Bacteria, most of the genes involved in transcription, translation, and replication in M. jannaschii are more similar to those found in Eukaryotes.

Simplification of emergency department discharge instructions improves patient comprehension.

STUDY OBJECTIVE: Emergency department patients have been shown to have difficulty understanding written discharge instructions. We attempted to determine whether improvements in comprehension can be achieved by simplification of available materials. DESIGN: We have previously tested patient understanding of standard discharge instructions. For this study, we simplified the standard instructions. Patients were given one of two simplified instruction sets. After reading the instructions, each patient was asked to answer five specific written questions about them. Results were compared with those from the original study. SETTING: ED of a large inner-city university hospital. PARTICIPANTS: Four hundred twenty-three adult ED patients who presented on randomly selected days. RESULTS: The current and original groups were well matched for demographic variables. Each subject's responses were analyzed for overall success and for success with individual questions. The mean score for the current group was significantly improved over that of the original group. A trend toward improvement was demonstrated in all demographic groups with use of the simplified instructions. CONCLUSION: Simplified written materials may help patients who do not understand current standard materials. Health care providers should simplify written materials to make them understandable to the greatest number of patients.

Ophthalmologic procedures.

Step-by-step instructions for the most common and difficult ophthalmologic procedures that are performed in an emergency department. Foreign body removal, including rust rings, is explained with an emphasis on limiting further injury to the corneal epithelium and stroma. Patching, irrigation, contact lens removal and corneal culture techniques are explained. Three methods of assessing intraocular pressure are described.

Effectiveness of transnasal butorphanol for the treatment of musculoskeletal pain.

A prospective, open-label study of the effectiveness of transnasal butorphanol in the treatment of pain resulting from musculoskeletal injuries. Twenty-eight patients with strains (n = 20), fractures (n = 6), contusions (n = 1), and stab wounds (n = 1) were included. All patients were examined by an attending level emergency medicine physician and deemed to have pain severe enough to warrant parenteral narcotic analgesia. All patients received an initial 1-mg dose of transnasal butorphanol. Subsequent dosing was flexible depending on response to the initial dose. All patients received pain relief from transnasal butorphanol, and only one requested alternative analgesic medication. Fifty-seven percent (n = 16) of patients noticed at least a little relief of pain within 5 minutes of administration and 93% (n = 26) received at least a little relief within 15 minutes. Seventy-one percent of the patients received a 50% reduction of pain within 60 minutes. No serious side effects were noted, but drowsiness occurred in 82% (n = 23) and dizziness in 54% (n = 15) of the patients. One patient discontinued participation in the study because of nausea. In this limited trial transnasal butorphanol proved to be a rapidly effective opioid analgesic. Further controlled studies comparing transnasal butorphanol with standard parenteral narcotics are needed.

Phorbol ester-induced transcription of an immediate-early response gene by human T cells is inhibited by co-treatment with calcium ionophore.

Human T cells require two discrete signals to initiate their proliferation. In Jurkat T cells the first signal can be provided by the phorbol ester TPA and the second by the calcium ionophore A23187. We have isolated a cDNA from Jurkat T cells representing mRNA induced by TPA but inhibited by simultaneous treatment of the cells with antibody, lectin, or A23187. Sequencing revealed identity of the Jurkat clone to a cDNA, termed ETR101, recently isolated from HL60 promyelocytic leukaemia cells and shown to be an immediate early gene expressed upon TPA stimulation of these cells [Shimizu et al.: J Biol Chem 266:12157, 1991]. The gene is also induced very rapidly upon TPA treatment of Jurkat cells and is superinduced by co-treatment with cycloheximide. The predicted amino acid sequence encoded by ETR101 has weak homology to JunB and JunD, therefore it is of some interest that these three genes share the chromosomal localization, 19p13.2. The divergent effects of TPA treatment upon cell proliferation and differentiation in different circumstances allow some speculation about a possible role for the ETR101 gene product upon cellular differentiation.

Splatter during jet irrigation cleansing of a wound model: a comparison of three inexpensive devices.

STUDY OBJECTIVE: Pressurized jet irrigation is commonly used to cleanse traumatic wounds but results in splatter of blood, a biohazard. Three inexpensive irrigation devices were compared to assess the degree of splatter produced: a 1.25-in. 18-gauge angiocath, an Irrijet Irrigation System with a 12.7-cm splash shield, and a Zerowet Splashield held directly against the wound (Zerowet-C) and held 4 to 10 cm from the wound, an incorrect technique (Zerowet-I). DESIGN: A standard laceration was created in pieces of beef. This wound model was placed 1 m from the floor. Paper grid sheets were placed on the irrigator's face and chest. Six grid sheets were suspended at the 9:00, 12:00, and 3:00 positions 1 m from the wound model and 1 and 1.5 m from the floor to simulate exposure to nearby individuals. Two grid sheets were placed flat on the floor, at the 10:30 and 1:30 positions, 1 m from the base of the wound model stand. The study area was contained in a 3 x 2 x 2 m plastic sheet enclosure to prevent air drafts. INTERVENTION: Ten irrigations were performed with the angiocath, Irrijet, Zerowet-I, and Zerowet-C. Each run used 200 mL methylene blue solution delivered with a 50-mL syringe by one-hand pressure. The methylene blue splatter on each of the grids was counted by size (diameter, less than 1 mm, more than 1 mm and less than 5 mm, more than 5 mm and less than 10 mm, and more than 10 mm). RESULTS: There was significantly less splatter onto the irrigator's face and chest with Irrijet, Zerowet-I, and Zerowet-C. No facial splatter occurred with Zerowet-C. There was significantly less splatter at the 9:00 and 12:00 positions at both heights, and on the floor with Irrijet, Zerowet-I, and Zerowet-C. Less significant splatter difference was noted at the 3:00 position. CONCLUSION: Irrijet, Zerowet-I, and Zerowet-C were superior to the angiocath in preventing splatter during this wound model irrigation. The correct use of Zerowet (Zerowet-C) was particularly effective in preventing splatter onto the irrigator's face.

Angioedema in the emergency department: the impact of angiotensin-converting enzyme inhibitors.

Angiotensin-converting enzyme (ACE) inhibitors have been reported to cause angioedema. The purpose of this study was to establish what proportion of patients who present to the emergency department (ED) with angioedema were concomitantly taking any of the ACE inhibitors and to show how this group differed in presentation and response to treatment from the larger population of patients with non-ACE inhibitor-related angioedema. An 8-year retrospective chart review of all patients with the diagnosis of angioedema observed from January 1, 1984 to December 31, 1991 was undertaken in the ED of an urban teaching hospital. Forty-nine patients ranging from 12 to 88 years of age with symptoms and physical examination that was consistent with the diagnosis of angioedema were entered onto the study. Twelve cases of ACE inhibitor-related angioedema were identified, all occurring in the last 4 years of the review, and when compared with the non-ACE inhibitor-related group were older (mean age, 63.3 vs 43.0 years), had less of an allergic history (0% vs 49%; P = .013), but demonstrated the same severity of symptoms and response to medical therapy. No case required an artificial or surgical airway. ACE inhibitor related angioedema is becoming a common type of angioedema observed in this ED. These patients are older and free of other allergic disease and respond well to traditional therapy.