Blast-furnace smelting as an example of an integrated approach to the design of gas-cleaning units

The experience that the company has gained in different sectors of industry, its huge inventory of completed projects, the excellent qualifications of its staff, the fact that it uses proven methods of calculation and observes the pertinent standards, and its collaborations with other leading Russian and foreign companies allow its specialists to not only devise sophisticated strategies for the reconstruction of existing facilities, but also to design highly efficient new gas-cleaning systems that meet customers’ requirements and satisfy international standards.     

Chromatographic and electrophoretic methods related to the carbonic anhydrase isozymes

There are three gene families that encode zinc metalloenzymes that catalyze the reversible hydration of CO2. The encoded enzymes are termed carbonic anhydrases (CAs). The CA isozymes have been purified from representatives of all types of organisms. Most CAs are strongly inhibited by aromatic sulfonamides. Several chromatographic and electrophoretic methods have been devised to determine binding constants for sulfonamides to CAs, and these compounds have been extensively used for, often single-step, affinity chromatographic separation of CAs from complex matrixes. The purification of different CA isozymes from different organisms is reviewed, as are methods for detection of CAs during chromatography and electrophoresis.     

Carbonic anhydrase: a multigene-multifunctional enzyme

Carbonic anhydrase is a zinc metalloenzyme that catalyzes the simple interconversion between carbon dioxide (CO2) and bicarbonate (HCO3-). Seven genes encode the CA isozymes in vertebrates. They are single chain peptides termed CAI-VII. One CA isozyme is present in teleost fish. Three isozymes clearly appear together in birds. All seven types appear in mammals. Despite the great similarity among these isozymes, they present strong differences with respect to their kinetic properties. Many physiological and biochemical processes are related to the activity of CA isozymes.     

A noble approach to mechanisms

We undertook a study to determine the efficacy of stents in reducing restenosis in cardiac allograft vasculopathy. The result shows that coronary stenting significantly reduces restenosis in cardiac allograft vasculopathy compared with balloon angioplasty alone.     

Collapsed ultraendurance athlete: proposed mechanisms and an approach to management

OBJECTIVE: To review the common conditions causing collapse in ultraendurance athletes, to propose appropriate treatment protocols for the more common medical conditions that are encountered, and to provide practical guidelines for the management of the medical facilities at these endurance events. DATA SOURCES: Books published on the subject, abstracts of the American College of Sports Medicine Annual Congress dealing with the subject over the last 5 years, and electronic search of the Medline and Current Contents databases (last searched May 1995). German articles were included in the search criteria. STUDY SELECTION: Articles dealing generally with the management of medical facilities at endurance events were chosen. Articles dealing more specifically with the common medical conditions encountered at these events were then sourced and included in this review. DATA EXTRACTION: Multiple reader extraction of relevant data. DATA SYNTHESIS: A practical guideline to the management of the medical facility at an endurance event is detailed, expanding specifically on the nature of the conditions causing collapse during or after endurance exercise with a proposed classification of causes of collapse for optimizing immediate management and management protocols for specific conditions such as heatstroke, hyponatremia, hypoglycemia, exercise-associated collapse, and muscle cramps. CONCLUSION: The most commonly encountered medical condition at endurance athletic events is collapse after the event. The popular view that all persons who collapse have dehydration-induced hyperthermia has been challenged. Here we extend that argument and provide diagnostic and management protocols and propose a triage system that considers the most common causes of collapse in ultraendurance athletes. These protocols can optimize the efficient and safe management of large numbers of collapsed ultraendurance athletes. It is proposed that these protocols can optimize the efficient and safe management of large numbers of collapsed ultra endurance athletes.     

Dorzolamide: development and clinical application of a topical carbonic anhydrase inhibitor

Systemic carbonic anhydrase inhibitors are among the most powerful agents to lower intraocular pressure. Unfortunately, their use is frequently accompanied by undesired side effects. Some are due to the relatively large amounts of drug that have to be systemically administered to inhibit the carbonic anhydrase in the ciliary processes. Recently, dorzolamide, a topical carbonic anhydrase inhibitor, has become commercially available for clinical use. This article reviews the development of topical carbonic anhydrase inhibitors with special reference to dorzolamide. When administered three-times daily, dorzolamide lowers intraocular pressure in a clinically useful manner. Ocular side-effects include frequent stinging and burning and allergy can develop. Systemic side effects have not been observed that could definitively be related to inhibition of extraocular carbonic anhydrase. Blood dyscrasias have not yet been observed. Absence of cardiovascular and pulmonary side effects, as can occur with beta adrenergic antagonists, and lack of pupillary and accommodative stimulation, as occur with cholinergic agonists, might make dorzolamide first-line medical treatment for elevated intraocular pressure.     

Clinical and molecular heterogeneity in carbonic anhydrase II deficiency and prenatal diagnosis in an Italian family

Carbonic anhydrase (CA) II deficiency is characterized by osteopetrosis, renal tubular acidosis, cerebral calcification, and usually severe mental retardation. We describe an Italian boy with this disease whose mental retardation was relatively mild and whose renal tubular acidosis had only a distal component. A novel mutation of a gt-->tt change of splice donor site at the 5' end of intron 6 was demonstrated. Comparison of this patient with two previous Italian families with different mutations illustrates the clinical and molecular heterogeneity of this disease. The identification of the mutation in this family provided the opportunity for prenatal diagnosis in a subsequent pregnancy.     

Cloning, sequencing, and recombinant expression of the porcine inhibitor of carbonic anhydrase: a novel member of the transferrin family

The plasma from many vertebrates contains a component that specifically binds and inhibits carbonic anhydrase II with nanomolar affinity. Amino-terminal sequencing of pICA, the previously identified 79-kDa carbonic anhydrase inhibitor isolated from porcine plasma [Roush, E. D., & Fierke, C. A. (1992) Biochemistry 31, 12536-12542], and sequencing of four proteolytic fragments of pICA revealed that each of the partial sequences has 40-80% sequence identity with members of the transferrin protein family. We describe here the isolation of a full-length cDNA clone of pICA from a lambda gt11 porcine liver cDNA library. Heterologous expression of this cDNA clone in a Pichia pastoris expression system led to the secretion into the medium of 5 mg/L of a 79-kDa protein that specifically reacts with anti-pICA antibodies and binds tightly to a carbonic anhydrase-Sepharose affinity column. Pairwise sequential alignment of pICA with various transferrins reveals an amino acid identity as high as 64% and predicts that 16 transferrin disulfide bonds are conserved. However, despite these structural similarities, the properties of pICA are distinct from the properties of transferrin. pICA exhibits a significantly decreased affinity for iron that can be attributed to the loss of one of the eight amino acids that coordinate iron in the transferrins as well as both of the arginine residues responsible for anion binding. In addition, the antigenic determinants of pICA and the transferrins are not identical. These data imply that pICA, along with saxiphilin, is a member of a diverse superfamily of transferrin-like proteins with functions other than iron binding.     

Genetic engineering as an approach to xenotransplantation

A discordant organ xenograft, such as a heart or kidney transplanted from pig to human, is rejected within 1 to 2 hours by a process called hyperacute rejection (HAR) caused in large or full measure by preexisting host xenoreactive natural antibodies (XNAs) and complement. HAR can be averted by blocking either complement or XNAs; but the xenograft is then rejected at 3 to 4 days by a process called delayed xenograft rejection (DXR), which can occur without the presence of T cells. DXR involves type II endothelial cell (EC) activation (the phase of activation that includes up-regulation of proinflammatory genes in the EC), infiltration into the graft of host monocytes and natural killer cells (both of which appear to be activated), and a complex cytokine picture. We discuss in this paper various approaches that might help prevent DXR, after which we assume that one would still have to deal with a xenograft counterpart of the T cell-mediated allograft rejection response. The approach to avoiding DXR focuses largely on genetic engineering of the ECs in the graft.     

Skills training as an approach to the treatment of heterosexual-social anxiety: A review.

Reviews experimental investigations of the effectiveness of social-skills training approaches to the treatment of heterosexual social anxiety. In general the studies support the skills-training treatment approach. However, these results should be interpreted with a certain degree of cautious optimism because many of the reviewed studies suffered from several methodological and procedural problems. The major methodological and procedural problems were concerned with S selection and screening, inadequate and invalid assessment procedures, lack of transfer and follow-up measurement, and inattention to the interaction between treatment procedures and S characteristics. These errors need to be rectified for investigators in this research area to make significant contributions to the various theories (conditioned anxiety, faulty cognitive-evaluative appraisal, and skills deficit) regarding the etiology and maintainers of heterosexual social anxiety and to the clinical treatment of such disorders. (49 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

新形势下的高校教材管理模式探索

在高等教育大众化和加入WTO的新形势下,高等学校的办学形式、办学层次日趋多样,特别是学分制、双语教学等改革的引入与深化,给教材管理带来严峻的挑战,传统的综合型教材管理模式已不再适应新形势下的教材管理需要。为应对这些挑战,本文提出双轨运作的教材管理模式,其要点在于充分利用专业化的社会分工,将教材的管理和经营分开,在管理上专业化,遵循教学规律,削除供应冗务,强化质量管理;在经营上社会化,遵循市场规律,通过引入竞争来获得优质服务,从而以最小的代价达到最优的管理目标。     

Diagnostics of persistent viruses: human cytomegalovirus as an example

Infections with persistent viruses such as herpesviruses have become of significant clinical importance with the increasing number of immunocompromised patients at risk to suffer from severe disease. As antiviral chemotherapy is available for herpesvirus infections, the diagnostic methods for rapid and sensitive detection of symptomatic infection have been developed and recently refined. In human cytomegalovirus (HCMV), the use of recombinant viral antigens provides a rationale to improve serological assays. This may be of use for the discrimination of primary versus secondary infection. Early diagnosis of symptomatic HCMV infection in immunosuppressed patients can be most effectively achieved by the detection of a viral tegument protein, pp65, in peripheral blood leukocytes. This early diagnosis has been shown to be of major importance for the effective treatment of these patients. HCMV infection in solid organs can be demonstrated by immunohistochemistry using monoclonal antibodies against viral proteins. HCMV involvement in diseases of the central nervous system in AIDS patients can be verified by the detection of very small amounts of HCMV DNA in cerebrospinal fluid by polymerase chain reaction. This method may prove useful for monitoring HCMV encephalitis and neuropathy.     

Screening derivatized peptide libraries for tight binding inhibitors to carbonic anhydrase II by electrospray ionization-mass spectrometry

This paper describes the use of electrospray ionization-mass spectrometry (ESI-MS) to screen two libraries of soluble compounds to search for tight binding inhibitors for carbonic anhydrase II (EC 4.2.1.1). The two libraries, H2NO2SC6H4C(O)NH-AA1-AA2-C(O)NHCH2CH2CO2H where AA1 and AA2 are L-amino acids (library size: 289 compounds) or D-amino acids (256 compounds), were constructed by attaching tripeptides to the carboxyl group of 4-carboxybenzenesulfonamide. Screening of both libraries yielded, as the tightest binding inhibitor, compound 1 (AA1 = AA2 = L-Leu; binding constant Kb = 1.4 x 10(8) M-1). The ability of ESI-MS to estimate simultaneously the relative binding affinities of a protein to soluble ligands in a library, if general, should be useful in drug development.     

Design, synthesis, and evaluation of tetrahydropyrimidinones as an example of a general approach to nonpeptide HIV protease inhibitors

Re-examination of the design of the cyclic urea class of HIV protease (HIVPR) inhibitors suggests a general approach to designing novel nonpeptide cyclic HIVPR inhibitors. This process involves the inversion of the stereochemical centers of the core transition-state isostere of the linear HIVPR inhibitors and cyclization of the resulting core using an appropriate cyclizing reagent. As an example, this process is applied to the diamino alcohol class of HIVPR inhibitors to give tetrahydropyrimidinones. Conformational analysis of the tetrahydropyrimidinones and modeling of its interaction with the active site of HIVPR suggested modifications which led to very potent inhibitors of HIVPR (24 with a Ki = 0.018 nM). The X-ray crystallographic structure of the complex of 24 with HIVPR confirms the analysis and modeling predictions. The example reported in this study and other examples that are cited indicate that this process may be generally applicable to other linear inhibitors.