bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering and characterization of human manganese superoxide dismutase mutants with high activity and low product inhibition
Authors: Chockalingam Karuppiah , Luba James , Nick Harry S. , Silverman David N. , Zhao Huimin
Published: September 2006

Human manganese superoxide dismutase is a mitochondrial metalloenzyme that is involved in protecting aerobic organisms against superoxide toxicity, and has been implicated in slowing tumor growth. Unfortunately, this enzyme exhibits strong product inhibition, which limits its potential biomedical applications. Previous efforts to alleviate human manganese superoxide dismutase product inhibition utilized rational protein design and site‐directed mutagenesis. These efforts led to variants of human manganese superoxide dismutase at residue 143 with dramatically reduced product inhibition, but also reduced catalytic activity and efficiency. Here, we report the use of a directed evolution approach to engineer two variants of the Q143A human manganese superoxide dismutase mutant enzyme with improved catalytic activity and efficiency. Two separate activity‐restoring mutations were found − C140S and N73S − that increase the catalytic efficiency of the parent Q143A human manganese superoxide dismutase enzyme by up to five‐fold while maintaining low product inhibition. Interestingly, C140S is a context‐dependent mutation, and the C140S–Q143A human manganese superoxide dismutase did not follow Michaelis–Menten kinetics. The re‐engineered human manganese superoxide dismutase mutants should be useful for biomedical applications, and our kinetic and structural studies also provide new insights into the structure–function relationships of human manganese superoxide dismutase.
Site‐directed mutagenesis of selected residues at the active site of aryl‐alcohol oxidase, an H2O2‐producing ligninolytic enzyme
Authors: Ferreira Patricia , Ruiz‐Dueñas Francisco J. , Martínez María J. , van Berkel Willem J. H. , Martínez Angel T.
Published: September 2006

Aryl‐alcohol oxidase provides H2O2 for lignin biodegradation, a key process for carbon recycling in land ecosystems that is also of great biotechnological interest. However, little is known of the structural determinants of the catalytic activity of this fungal flavoenzyme, which oxidizes a variety of polyunsaturated alcohols. Different alcohol substrates were docked on the aryl‐alcohol oxidase molecular structure, and six amino acid residues surrounding the putative substrate‐binding site were chosen for site‐directed mutagenesis modification. Several Pleurotus eryngii aryl‐alcohol oxidase variants were purified to homogeneity after heterologous expression in Emericella nidulans, and characterized in terms of their steady‐state kinetic properties. Two histidine residues (His502 and His546) are strictly required for aryl‐alcohol oxidase catalysis, as shown by the lack of activity of different variants. This fact, together with their location near the isoalloxazine ring of FAD, suggested a contribution to catalysis by alcohol activation, enabling its oxidation by flavin‐adenine dinucleotide (FAD). The presence of two aromatic residues (at positions 92 and 501) is also required, as shown by the conserved activity of the Y92F and F501Y enzyme variants and the strongly impaired activity of Y92A and F501A. By contrast, a third aromatic residue (Tyr78) does not seem to be involved in catalysis. The kinetic and spectral properties of the Phe501 variants suggested that this residue could affect the FAD environment, modulating the catalytic rate of the enzyme. Finaly, L315 affects the enzyme kcat, although it is not located in the near vicinity of the cofactor. The present study provides the first evidence for the role of aryl‐alcohol oxidase active site residues.
Data collection and the development of quality assurance for surgical specialities in Asia: A moral obligation?
Authors: Underwood Malcolm J. , Van Hasselt Andrew , Fung Hong
Published: September 2006

A ‘quality assurance’ process enables health care providers and receivers to be assured that delivery of care is appropriate, of a high standard and incorporates fiscal considerations. Many components contribute to this process but the initial emphasis should be robust data collection, validation and appropriate analysis. The implementation of such a process is particularly relevant to the surgical specialties in Asia.
Review of endovascular stent‐assisted embolization for management of intracranial aneurysms
Authors: Chan Tony Kam‐Tong , Lui Wai‐Man , Fan Yiu‐Wah
Published: September 2006

Objective:  This was a retrospective review of the results using stent‐assisted coil embolization for management of intracranial aneurysms.

Methods:  The records of seven patients treated with stent‐assisted Gugliemi detachable coil (GDC) embolization were retrieved from the authors’ prospectively maintained database. The clinical presentation, site and type of aneurysms, treatment procedure and complications, and outcome of these identified cases were reviewed.

Results:  Between January 2002 and May 2004, seven patients with intracranial aneurysms, four of which were ruptured, were treated by stent‐assisted GDC embolization. Four aneurysms were located at the anterior circulation and three were at the posterior circulation. The indications for stent use were: giant aneurysm (>2.5 cm), dissecting pseudo‐aneurysm, broad‐necked aneurysm and the need for preservation of important parent arteries or branches. Concerning the technical aspect, all except one had successful stent deployment. One stent dislodged after apparent successful deployment. GDC embolization was continued and the aneurysm was partially occluded. More than 90% occlusion of aneurysm sac was achieved in six aneurysms. Intraoperative complications included over‐coagulation, failure in stent deployment, displacement of stent, coil entrapment and thromboembolism. One patient had added focal neurological deficit after the procedure, and one became vegetative due to an unrelated cause. The patient in whom the stent was dislodged suffered another subarachnoid haemorrhage 4 months later and died.

Conclusion:  Percutaneous intracranial stent is a new and useful device to assist embolization of cerebral aneurysms that were previously not amenable to endovascular therapy. These preliminary results suggest that this procedure could achieve satisfactory outcomes without significant complications.
Preoperative methicillin‐resistant Staphylococcus aureus (MRSA) screening: An effective method to control MRSA infections on elective orthopaedics wards
Authors: Anwar Rahij , Botchu Rajesh , Viegas Manoj , Animashawun Yomi , Shashidhara Singapura , Slater Guy J. R.
Published: September 2006

Background:  Methicillin‐resistant Staphylococcus aureus (MRSA) infections continue to increase in UK hospitals despite the introduction of various control measures. These infections have serious clinical and economic implications, particularly in relation to elective orthopaedic surgery.

Methods:  A prospective study was performed from August 2003 to July 2004 to assess the effect of preadmission screening and ‘ring fencing’ of beds on the incidence of infection in an elective orthopaedics unit.

Results:  The preoperative incidence of MRSA colonization was 2.25% and 53% of these patients had at least one risk factor. There were no postoperative MRSA infections in the ring‐fenced orthopaedic unit.

Conclusions:  Preoperative screening and ring fencing reduced the MRSA incidence to zero in the operated patients. Mechanisms need to be developed where screening and isolation of MRSA cases can be performed in most, if not all, hospital admissions.
Single surgeon’s experience with Furlow palatoplasty and the fistula rate
Authors: Mak Anthony Sze‐Yuen , Wong Wai‐Hong , Or Chi‐Kong , Poon Angela Ming‐See
Published: September 2006

Objective:  To review the clinical data on Furlow palatoplasty and the incidence of palatal fistula.

Methods:  A retrospective review was conducted of clinical data and incidence of palatal fistula in all cleft palate patients undergoing Furlow palatoplasty by one surgeon in Princess Margaret Hospital from November 1997 to February 2003.

Results:  Of the 54 patients (29 male, 25 female) treated, five (9.3%) had positive family history of cleft lip/cleft palate. Twenty‐two patients (40.7%) had associated cleft lip and four (7.4%) had other congenital malformations. Thirty‐one palates were Veau classes I & II; 15 were class III, six were class IV, and two were submucous clefts. The mean ± SD patient age was 22.8 ± 11.9 months, and follow‐up period 50.6 ± 17.5 months with five (9.3%) defaulted. Blood loss and operation time were significantly different among the different classes of clefts. There was one case of postoperative bleeding requiring immediate opening. Three palatal fistulae occurred, all within the first 3 years of the study period. Two were repaired with no recurrences.

Conclusions:  The surgeon’s incidence of palatal fistula after Furlow palatoplasty is 5.6%, comparable to the low incidence reported by other surgeons using other methods of repair.
Formalin dab for refractory radiation proctitis: Preliminary Hong Kong experience
Authors: Ng Simon Siu‐Man , Ng Nancy Ching , Lee Janet Fung‐Yee , Yiu Raymond Ying‐Chang , Li Jimmy Chak‐Man , Leung Ka‐Lau
Published: September 2006

Objective:  This prospective study aimed to evaluate the efficacy and safety of 4% formalin dab in managing patients with refractory radiation proctitis.

Methods:  From January 2001 to December 2004, 11 patients with radiation proctitis who did not respond to regular steroid enemas and/or argon plasma coagulation were treated with local application of 4% formalin‐soaked gauze (formalin dab). Main outcome measures were control of bleeding, changes in haemoglobin level, hospitalization and blood transfusion requirements, and complications.

Results:  The mean haemoglobin level before formalin dab was 7.3 ± 2.4 g/dL. Eight patients had required repeated admissions to hospital for blood transfusions (median 4 units; range, 2–27 units). The median number of sessions of formalin dab was two (range, 1–6). The treatment was effective in 10 patients (90.9%): four patients had complete cessation of bleeding and six patients had improvement of symptoms. At a median follow‐up of 15.3 months, only three patients required hospital admission once for blood transfusions (range 1–2 units). The mean haemoglobin level after formalin dab was 10.4 ± 2.2 g/dL, which was significantly higher than that before formalin dab (P = 0.007). No patient developed complications after formalin dab.

Conclusions:  Formalin dab is an effective and safe treatment modality for refractory radiation proctitis.
Review of solid‐pseudopapillary tumour of the pancreas with case illustration
Authors: Shabbir Asim , Teo Clarence Hai‐Yi , Leow C. K.
Published: September 2006

Solid‐pseudopapillary tumour of the pancreas (SPT) is a rare neoplasm known to affect predominantly young women. The presenting symptoms can be vague and non‐specific. The case is described of SPT in a 46‐year‐old Chinese man who presented with postprandial bloatedness and a left upper quadrant mass. A review of the literature on the clinical characteristics, pathology and management of SPT is presented.
Laparoscopic repair of Morgagni diaphragmatic hernia
Authors: Tong Raymond Sze‐Kin , Jacobs Rod , McLaughlin Stephen
Published: September 2006

Background:  Morgagni diaphragmatic hernia is a rare congenital hernia that lies retrosternal through a congenital defect between the sternal and costal portions of the diaphragm. Surgical repair of Morgagni hernia is recommended because incarceration or strangulation of bowel within the thoracic cavity may occur.

Methods:  A case of Morgagni diaphragmatic hernia is presented and laparoscopic repair using Gore‐Tex DualMesh is described.

Results:  There was complete resolution of the patient’s symptoms including her dyspnoea. There were no postoperative complications.

Conclusion:  Laparoscopic repair of Morgagni diaphragmatic hernia is a safe and effective method for treating this rare surgical condition. The use of dual‐layer mesh allows tension‐free repair without the risk of intra‐abdominal adhesions forming between bowel and mesh.
Sonographic diagnosis of early recurrence after inguinal herniorrhaphy: Potential pitfalls
Authors: Ng Simon Siu‐Man , Wong Jeffrey Ka‐Tak , Lai Paul Bo‐San
Published: September 2006

Three patients who presented with scrotal swelling within a few days of inguinal herniorrhaphy are reported. Ultrasonography scans performed in these patients all demonstrated features suspicious of recurrence of hernia. One patient underwent surgical exploration, which revealed only a scrotal haematoma without evidence of recurrent hernia. The other two patients were managed conservatively because clinically the swellings were regarded to be more compatible with haematoma. Both patients had subsequent resolution of the scrotal swelling with no clinical evidence of recurrence of hernia on follow‐up. It is concluded that sonographic diagnosis of recurrence of hernia shortly after inguinal herniorrhaphy can occasionally be misleading.
Laparoscopic repair of obturator hernia
Authors: Chan Eva Sze‐Wah , Tang Chung‐Ngai , Ha Joe Ping‐Yiu , Li Michael Ka‐Wah
Published: September 2006

Management of patients presenting with bowel obstruction secondary to oburator hernia is difficult due to the rarity of the condition. Herein, two patients with incarcerated obturator hernia are presented, and the role of diagnostic laparoscopy in their management is discussed. A new surgical approach, transabdominal repair with dual mesh, is described.
An overview of ethnicity and assessment of family history in primary care settings
Authors: Maradiegue Ann , Edwards Quannetta T.
Published: September 2006

Purpose: To discuss the importance of and the nurse practitioner’s (NP’s) role in the assessment of ethnicity/family of origin in conducting a multigenerational family history in primary care settings.

Data sources: A review of the literature on past research results addressing racial and ethnic disparities and current articles from scientific journals exploring the relationship between race and genetics. Web sites were from the National Institutes of Health, the Human Genome Research Institute, the National Cancer Institute, and the Health and Human Services Minority Health and Disparities report.

Conclusions: The family history has received renewed interest due to the sequencing of the human genome. A multigenerational family history is an important first step in screening for a multitude of disorders impacted by genetic susceptibility, shared environments, and common behaviors. Assessment of the patient’s ethnicity/family of origin is an integral part of the multigenerational family history, particularly in the diagnosis of chronic diseases and the assessment of risks for genetic disorders. The multigenerational family history is important in diagnosis, predictive genetic testing, disease prevention, and health promotion. Challenges facing NPs and the utilization of a multigenerational family history in the current U.S. health system include (a) training clinicians on the correct assessment and utilization of a multigenerational family history, (b) assessment of the subtleties of ethnicity and identifying multiple ethnic groups within a family, (c) collection of the family history in a manner that is sensitive to the cultural beliefs of individuals, and (d) avoidance of stereotyping

Implications for practice: Significant advances in genetics and genetic testing requires that NPs be well versed in collecting and interpreting a multigenerational family history to include assessment of the patient/family’s ethnicity/family of origin. The ability to effectively conduct and evaluate the individual’s and family’s health risk through a multigenerational family history will be important in diagnosis, health promotion, disease prevention, and the determination for genetic counseling referral and predictive testing when appropriate. Assessment of risk and prevention of disease is also important in reducing health disparities.
Reconsidering the effects of monosodium glutamate: A literature review
Authors: Freeman Matthew
Published: September 2006

Purpose: This article reviews the literature from the past 40 years of research related to monosodium glutamate (MSG) and its ability to trigger a migraine headache, induce an asthma exacerbation, or evoke a constellation of symptoms described as the “Chinese restaurant syndrome.”

Data sources: Literature retrieved by a search using PubMed, Medline, Lexis‐Nexus, and Infotrac to review articles from the past 40 years.

Conclusions: MSG has a widespread reputation for eliciting a variety of symptoms, ranging from headache to dry mouth to flushing. Since the first report of the so‐called Chinese restaurant syndrome 40 years ago, clinical trials have failed to identify a consistent relationship between the consumption of MSG and the constellation of symptoms that comprise the syndrome. Furthermore, MSG has been described as a trigger for asthma and migraine headache exacerbations, but there are no consistent data to support this relationship. Although there have been reports of an MSG‐sensitive subset of the population, this has not been demonstrated in placebo‐controlled trials.

Implications for practice: Despite a widespread belief that MSG can elicit a headache, among other symptoms, there are no consistent clinical data to support this claim. Findings from the literature indicate that there is no consistent evidence to suggest that individuals may be uniquely sensitive to MSG. Nurse practitioners should therefore concentrate their efforts on advising patients of the nutritional pitfalls of some Chinese restaurant meals and to seek more consistently documented etiologies for symptoms such as headache, xerostomia, or flushing.
Beta‐blocker medication usage in older women after myocardial infarction
Authors: Crane Patricia B. , Oles Karen S. , Kennedy‐Malone Laurie
Published: September 2006

Purpose: The purpose of this study was to assess demographic characteristics of women prescribed beta‐blocker (β‐blocker) medication and compare to those not using β‐blocker medication, and to determine if there are differences in depression and fatigue among women who used β‐blockers compared to nonusers 6–12 months after myocardial infarction (MI).

Data sources: This was a descriptive cross‐sectional study of 84 women (61 using β‐blockers and 23 not using β‐blockers) aged 65 and older who were 6–12 months post‐MI. Women had their height and weight measured and completed a Demographic Health Form, the Geriatric Depression Scale, and the Revised Piper Fatigue Scale (RPFS).

Conclusions: While most of the women were taking β‐blockers after MI (74%), significantly fewer Black women were taking β‐blockers (χ2= 5.086, p= 0.032). Most of the β‐blocker users were overweight or obese. There were no significant differences in age, t(82) = 0.7, p= 0.486; body mass index, t(82) = 0.76, p= 0.445; income, χ2(df = 2) = 3.219, p= 0.075; mean depression, t(82) = 1.648, p= 0.103; or fatigue scores, t(82) = 0.993, p= 0.324, between β‐blocker users and nonusers. More of those not taking β‐blockers reported fatigue with significantly higher fatigue in the affective meaning dimension of the RPFS, t(82) = 2.272, p= 0.03.

Implications for practice: β‐Blocker medication continues to be underutilized in older women. Because no difference was noted in fatigue and depression in the two groups, these may mean that these side effects are not barriers in prescribing this medication post‐MI. Nurse practitioners are in pivotal positions to monitor the ongoing physiological and psychological sequelae post‐MI and implement interventions to improve their outcomes.
Health behaviors in breast cancer survivors experiencing bone loss
Authors: Twiss Janice J. , Gross Gloria J. , Waltman Nancy L. , Ott Carol D. , Lindsey Ada M.
Published: September 2006

Purpose: To describe the baseline healthy lifestyle behaviors (dietary, calcium, vitamin D, caffeine and alcohol intake, smoking history, and physical activity) of postmenopausal breast cancer survivors (BCS); and to identify any relationship of healthy lifestyle behaviors with bone mineral density (BMD) at the forearm, total hip and spine, L1‐L4.

Data sources: Self‐reported responses to a demographic and health status questionnaire, to a 3‐day Diet Record, and to the 7‐Day Physical Activity Questionnaire‐Adapted provided data for the lifestyle behaviors. Baseline BMD (g/cm2) was determined with dual‐energy x‐ray absorptiometry (DEXA). Height, weight, and body mass index (BMI) were also measured in each of the 249 postmenopausal BCS.

Conclusions: There was an imbalance between consumed kilocalories and expenditure of energy. The majority of BCS were overweight or obese. They consumed less fruit and vegetable servings than recommended by the new 2005 U.S. Department of Agriculture’s dietary guidelines, less dairy products, below average recommended grains and fiber, less protein and carbohydrate intake, and a slightly higher fat gram intake. Approximately, 43% did not take any supplemental calcium, with 46% taking less than 1000 mg a day. Likewise, 52.59% consumed less than 400 IU of vitamin D with both supplemental and dietary intake. This group of BCS consumed below accepted levels of caffeine and alcohol. Only 18 BCS continued to smoke. This group spent an average of 10.36 h in light (sedentary) activities on a daily basis. There were significant negative relationships with bone mass (g/cm2) at the total hip and daily intake of caffeine/mg and daily grams of alcohol. Weight and BMI both demonstrated a significant relationship with bone mass (g/cm2) at the total hip, spine L1‐L4, and the forearm.

Implications for practice: The healthcare provider must incorporate appropriate teaching strategies, intensive counseling, and coaching, along with a support mechanism, to enable BCS to understand the importance of a healthy diet, calcium, and vitamin D supplement, and a regular strength/weight program that will be integrated into their daily lifestyle. Early DEXA screens should be part of the protocol with BCS, and there is a particular need for forearm DEXA screens to be included in the treatment protocol for BCS.
Evidence‐based practice: Review of clinical evidence on the efficacy of glucosamine and chondroitin in the treatment of osteoarthritis
Authors: Distler John , Anguelouch Amanda
Published: September 2006

Purpose: To evaluate past and current evidence from randomized controlled trials on the efficacy of glucosamine sulfate (GS), glucosamine hydrochloride (GH), and chondroitin sulfate (CS) for the treatment of osteoarthritis (OA).

Data sources: An extensive review of four meta‐analyses and a review of the findings of the recently published Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT) funded by the National Institutes of Health.

Findings: Review of previous studies on the efficacy of GS, GH, and CS in the treatment of OA showed inconclusive results because of weak research design. The GAIT attempted to provide clarity on the use of GH and CS in treating knee pain from OA by using a rigorous research design to elicit cause and effect. The GAIT results showed that GH and CS were not effective in reducing knee pain in the study group overall; however, these may be effective in combination for patients with moderate‐to‐severe knee pain.

Implications for practice: There is now clinical evidence indicating that recommending GS, GH, and CS for the treatment of mild knee pain from OA is ineffective. Further research needs to be done to identify specific characteristics in patients that results in a positive response. Until the findings of the GAIT undergo further peer review, the results of the research needs to be interpreted with caution.
Conformational Analysis of R207910, a New Drug Candidate for the Treatment of Tuberculosis, by a Combined NMR and Molecular Modeling Approach
Authors: Gaurrand Sandrine , Desjardins Stéphanie , Meyer Christophe , Bonnet Pascal , Argoullon Jean‐Michel , Oulyadi Hassan , Guillemont Jérôme
Published: September 2006

R207910 is an enantiomeric compound from a new class of antimycobacterial agents, the diarylquinolines [Science; 307:223 (2005)]. As enantiospecific interaction is required for biologic activity, we have undertaken a combined nuclear magnetic resonance and molecular modeling study to gain new insights into its conformation in solution and its absolute configuration. A conformational analysis using a Monte‐Carlo method has been performed on each of the four possible stereomers of this compound leading to the identification of their most stable conformation. Additional ab initio calculation was performed with emphasis on the strength of the observed intramolecular hydrogen bond. Simultaneously, a complete structural identification has been carried out by a set of monodimensional and bidimensional 1H‐13C‐NMR experiments. Determination of inter‐proton distances has been achieved by a series of 1H‐1H ROESY NMR experiments with different mixing times followed by a volume quantification of the correlations peaks. These experimental data were compared with the theoretical distances obtained from the conformational analysis. The remarkable match shows that R207910 adopts one of the low‐energy conformations predicted by molecular modeling and belongs to the (RS, SR) couple of diastereoisomers. A posteriori validation of our approach has been performed by X‐ray structure determination that concluded for the RS configuration.
Discovery of Synthetic Penaeidin Activity against Antibiotic‐resistant Fungi
Authors: Cuthbertson Brandon J. , Büllesbach Erika E. , Gross Paul S.
Published: September 2006

Penaeidins are antimicrobial peptides from shrimp that are constituted by divergent classes of peptide isoforms in an individual organism. Penaeidin sequence variation suggests functional diversity in the host and promises differential activities if applied to treat infections in humans. We have synthesized isoform 4 of penaeidin class 3 from the Atlantic shrimp, Litopenaeus setiferus, by native ligation using three peptide segments. Our synthesis approach led to the discovery of an irreversible side reaction that was successfully suppressed, a discovery, which has particular relevance to the synthesis of cysteine‐rich peptides. The antimicrobial activity of full‐length penaeidin and the N‐terminal proline‐rich domain of this isoform were compared with the corresponding peptides of penaeidin class 4 isoform 1 using a wide range of bacteria and fungi. New aspects of penaeidin function are reported that include activity against fungi of the phylum Basidiomycota (Cryptococcus strains), activity against fungi that are pathogenic to humans and effectiveness in the context of antibiotic resistance mechanisms (Cryptococcus and Candida spp.). The proline‐rich domain of penaeidin class 4 shows the highest relative antimicrobial activity, while exhibiting no cytotoxicity to human monocytes, and therefore stands out as a potential peptide therapeutic.
Selection of Novel Nickel‐binding Peptides from Flagella Displayed Secondary Peptide Library
Authors: Dong Jie , Liu Chuan , Zhang Jie , Xin Zhong‐Tao , Yang Guang , Gao Bo , Mao Can‐quan , Liu Nong‐Le , Wang Fang , Shao Ning‐Sheng , Fan Ming , Xue Yan‐Ning
Published: September 2006

Nickel (Ni) performs its biological or toxic functions in nickel–protein coordination form. Novel Ni‐binding peptides were isolated from a random dodecapeptide library displayed on the flagella of Escherichia coli against immobilized ions. On the basis of isolated sequences rich in histidine residues, two secondary libraries were constructed respectively. By consequent selection, more Ni‐chelating peptides were identified and the consensus motif RHXHR (where X was always H) was deduced. The result suggested that not only histidine, but also arginine, play an important role in Ni‐binding. Furthermore, two selected clones (1035 and 2022) were chosen for further identification. They exhibited similar relative binding affinity, which was about nine times that of the original library derived clones and statistically much more significant than the positive control with polyhistidine insert. Free nickel ions could almost completely inhibit the binding of the clones 1035 and 2022 to immobilized nickel, implicating that the peptides were able to chelate nickel ions. These studies reveal that bacterial surface displayed peptide libraries may have promising future potential for the development of metal bioadsorbents. Furthermore, novel Ni‐binding peptides may provide lead molecules for Ni‐chelation and applications thereof.
Identification and Molecular Diversity of T‐superfamily Conotoxins from Conus lividus and Conus litteratus
Authors: Luo Sulan , Zhangsun Dongting , Wu Yong , Zhu Xiaopeng , Xie Lei , Hu Yuanyan , Zhang Jizhen , Zhao Xi
Published: September 2006

The T‐superfamily conotoxins comprise a large and diverse group of biologically active peptides and are widely distributed in venom ducts of all major feeding types of Conus. Six novel T‐superfamily peptides from the two worm‐hunting cone snail species of Conus lividus andConus. litteratus native to Hainan were identified and determined to share a common signal sequence as well as a conserved arrangement of cysteine residues (CC–CC). The predicted mature peptides consist of 11–15 amino acids only. Phylogenetic analyses of new conotoxins from C. lividus andC. litteratus in present study and published homologue T‐superfamily sequences from the other Conus species was systematically performed. Phylogenetic trees, residue substitutions to view evolutionary relationships of the precursors’ signal, propeptide, and mature toxin regions were explored, as well as residue frequency component and cystine codon usage. Percent divergence of the amino acid sequences of the signal‐region exhibited high conservation, whereas the sequences of the mature peptides ranged from high similarity to high divergence between inter‐ and intro‐species. Notably, diversity of pro‐peptide region was also high with intermediate percent divergence between that observed in signal and toxin‐regions. Consensus hydrophobic residues Leu, Val, Ala, Ile and Pro of signal regions were abundant, whereas among propeptides, basic residues Arg and Lys and acidic residue Asp, addition of hydrophilic residues Thr and Ser were abundant. Residue frequency components were hypervariable in mature toxin region except for highly conservative cystine frame residues. The T‐superfamily conotoxins have been previously found mainly in piscivorous and molluscivorous cone snails. The newly identified six T‐superfamily peptides described in this investigation exemplify the first to be found from vermivorousC. lividus andC. litteratus. The elucidated cDNAs of the six toxins will facilitate a better understanding of the relationship between structure and function as well as provide a framework for their further research and development.
Examination of Two Independent Kinetic Assays for Determining the Inhibition of Carbonic Anhydrases I and II: Structure–Activity Comparison of Sulfamates and Sulfamides
Authors: Shank Richard P , McComsey David F , Smith‐Swintosky Virginia L , Maryanoff Bruce E
Published: September 2006

Enzyme inhibition assays often require deviations from physiological conditions. For carbonic anhydrases, procedures involving native CO2 and non‐native substrates have been used. We compared a native and a non‐native substrate in the context of inhibition of human carbonic anhydrases I and II by examining various sulfamate and sulfamide compounds in two kinetic assays: hydration of CO2 and hydrolysis of 4‐nitrophenylacetate. For carbonic anhydrase II, the two assays consistently generated similar Ki values, with the relative difference between the assays never exceeding 2.5‐fold. However, for carbonic anhydrase I there was more variability between the two assays, with Ki values for three compounds differing by more than 2.5‐fold, up to eightfold. In the CO2 hydration assay, some sulfamates and sulfamides exhibited mixed kinetics or partial inhibition. Our results indicate that Ki or Kd values from carbonic anhydrase assays involving non‐native substrates should be confirmed by assays that use CO2 (or HCO), to establish pharmacological relevance. From structure–activity comparisons, the sulfamate is more effective than the sulfamide in inhibiting carbonic anhydrase I and II, but the sulfamate does not confer selectivity. In contrast, the sulfonamide confers selectivity for carbonic anhydrase I (10‐ to 30‐fold). Selectivity for carbonic anhydrase II occurred with the substituted fructose moiety, especially the d‐enantiomer (>100‐fold).
ON THE MASLOV INDEX OF LAGRANGIAN SUBMANIFOLDS OF GENERALIZED CALABI–YAU MANIFOLDS
Authors: DE BARTOLOMEIS PAOLO , TOMASSINI ADRIANO
Published: September 2006

We characterize the special Lagrangian submanifolds of a generalized Calabi–Yau manifold, with vanishing Maslov class. Then, we carefully describe several examples, including a non-Kähler generalized Calabi–Yau manifold foliated by special Lagrangian submanifolds.
EMBEDDING RIEMANN SURFACES PROPERLY INTO ℂ2
Authors: WOLD ERLEND FORNÆSS
Published: September 2006

For certain bordered submanifolds M ⊂ ℂ2 we show that M can be embedded properly and holomorphically into ℂ2. An application is that any subset of a torus with two boundary components can be embedded properly into ℂ2.
UNIPOTENT REDUCTION AND THE POINCARÉ PROBLEM
Authors: ZAMORA ALEXIS G.
Published: September 2006

Given a fibration f : S → ℙ1, and the associated foliation [Formula: see text], the problem of bounding the genus of the general fiber of f in terms of the sheaf [Formula: see text] is studied. Using unipotent reduction of f, several bounds are obtained, under positivity assumptions on [Formula: see text]. In Sec.4, the Poincaré problem is solved, for non-degenerate [Formula: see text], assuming that all the eigenvalues of the linear part of [Formula: see text] near singularities are greater than 3.
HOMOLOGY 3-SPHERES IN CODIMENSION THREE
Authors: TAKASE MASAMICHI
Published: September 2006

For smooth embeddings of an integral homology 3-sphere in the 6-sphere, we define an integer invariant in terms of their Seifert surfaces. Our invariant gives a bijection between the set of smooth isotopy classes of such embeddings and the integers. It also gives rise to a complete invariant for homology bordism classes of all embeddings of homology 3-spheres in the 6-sphere. As a consequence, we show that two embeddings of an oriented integral homology 3-sphere in the 6-sphere are isotopic if and only if they are homology bordant. We also relate our invariant to the Rohlin invariant and accordingly characterize those embeddings which are compressible into the 5-sphere.
EULER OBSTRUCTION, POLAR MULTIPLICITIES AND EQUISINGULARITY OF MAP GERMS IN $\mathcal{O}(n,p), n < p$
Authors: JORGE PÉREZ V. H. , SAIA M. J.
Published: September 2006

There are two main goals in this article, one of them is to minimize the number of invariants needed to obtain Whitney equisingular one parameter families of finitely determined holomorphic map germs ft:(ℂn,0) → (ℂp,0), with n < p. The other is to show how to compute the local Euler obstruction of the stable types which appear in a finitely determined map germ in these dimensions.

The polar multiplicities of all stable types and the 0-stable singularities are the invariants that guarantee the Whitney equisingularity of such families and the polar multiplicities are the numbers that also allow us to compute the local Euler obstruction. Therefore our first step is to describe all stable types which appear when n < p and show the relationship between the polar multiplicities in each stable type. Using the fact that these polar multiplicities are upper semi-continuous we minimize the number of invariants that guarantee Whitney equisingularity of such a family. We also apply the relationship between the polar multiplicities in each stable type and a result of Lê and Teissier to show how to compute the local Euler obstruction of the stable types which appear in these dimensions.
PHENOMENOLOGY IN COMPUTATIONAL MODELS OF CONSCIOUSNESS
Authors: ALEKSANDER IGOR , MORTON HELEN
Published: September 2006

In this paper we argue that phenomenology needs to be supported by explicit mechanisms if one is to have computational models of consciousness. Computational work in this area is reviewed and a set of axioms that help to decompose being conscious into manageable concepts is evoked. This leads to a kernel architecture and a digital implementation which is shown to work in examples of visual illusions that are revealing of how the brain supports phenomenology. This model is used to address the unstable phenomenology related to observation of the ambiguous Necker cube.
MODELING THE BRAIN'S OPERATING SYSTEM USING VIRTUAL HUMANOIDS
Authors: BALLARD DANA , SPRAGUE NATHAN
Published: September 2006

Much of the allocation of human resources to tasks is studied under the rubric of "attention". However this is a very low-dimensional characterization of a system that has many degrees of freedom. To make progess in understanding human brain resource allocations, we will need to understand its basic functions at an abstract level. One way of accomplishing such an integration is to create a model of a human that has a useful amount of complexity. Essentially, one is faced with proposing an embodied "operating system" model that can be tested against human performance. Recently, technological advances have been made that allow progress in this direction. Graphic models that simulate extensive human capabilities can be used as platforms to develop synthetic models of visuo-motor behavior. Currently, such models can capture only a small portion of a full behavioral repertoire, but for the behaviors that they do model, they can describe complete visuo-motor subsystems at a level of detail that can be tested against human performance in realistic environments. This paper outlines one such model and shows both that it can produce interesting new hypotheses as to the role of vision and also that it can greatly enhance our understanding of a more multifacted characterization attention in visuo-motor tasks.
POSE-EXPRESSION NORMALIZATION FOR FACE RECOGNITION USING CONNECTED COMPONENTS ANALYSIS
Authors: CHOI JAE-YOUNG , WHANGBO TAEG-KEUN , YANG YOUNG-GYU , VISWANATHAN MURLIKRISHNA , KIM NAK-BIN
Published: September 2006

Accurate measurement of poses and expressions can increase the efficiency of recognition systems by avoiding the recognition of spurious faces. This paper presents a novel and robust pose-expression invariant face recognition method in order to improve the existing face recognition techniques. First, we apply the TSL color model for detecting facial region and estimate the vector X-Y-Z of face using connected components analysis. Second, the input face is mapped by a deformable 3D facial model. Third, the mapped face is transformed to the frontal face which appropriates for face recognition by the estimated pose vector and action unit of expression. Finally, the damaged regions which occur during the process of normalization are reconstructed using PCA. Several empirical tests are used to validate the application of face detection model and the method for estimating facial poses and expression. In addition, the tests suggest that recognition rate is greatly boosted through the normalization of the poses and expression.
LEARNING GRAPHS FROM EXAMPLES: AN APPLICATION TO THE PREDICTION OF THE TOXICITY OF CHEMICAL COMPOUNDS
Authors: FOGGIA PASQUALE , LIMONGIELLO ALESSANDRO , TUFANO FRANCESCO , VENTO MARIO
Published: September 2006

A common problem encountered in structural pattern recognition is the difficulty of constructing classification models or rules from a set of examples, due to the complexity of the structures needed to represent the patterns. In this paper, we present an extension of a method for structural learning. The goal of the method is to find descriptions which are general (in other words, are successfully applicable to recognize objects different from the ones in the training set), preserving at the same time their discrimination ability. This method has been applied to predictive toxicology evaluation, that is the inference of the cancerogenic characteristics of chemical compounds.
ON THE HIERARCHICAL ASSIGNMENT TO THE FOREGROUND OF GRAY-LEVEL IMAGE SUBSETS
Authors: FRUCCI MARIA , ARCELLI CARLO , SANNITI DI BAJA GABRIELLA
Published: September 2006

We present a method to assign to either the foreground or the background the regions into which a gray-level image is partitioned by watershed transformation. Our method is inspired by visual perception in the sense that the border separating any foreground component from the background is detected in correspondence with the locally maximal gray-level changes through the image. The method is implemented as consisting of three steps. The first two steps perform a basic assignment of the regions, while the remaining step examines again some regions tentatively assigned to the background during the second step and possibly changes their status. A feature of the method is that a hierarchical ranking of the regions assigned to the foreground is also accomplished.
EFFECT OF HIGH CURVATURE POINT DELETION ON THE PERFORMANCE OF TWO CONTOUR BASED SHAPE RECOGNITION ALGORITHMS
Authors: GHOSH ANARTA , PETKOV NICOLAI
Published: September 2006

Psychophysical researches on the human visual system have shown that the points of high curvature on the contour of an object play an important role in the recognition process. Inspired by these studies we propose: (i) a novel algorithm to select points of high curvature on the contour of an object which can be used to construct a recognizable polygonal approximation, (ii) a test which evaluates the effect of deletion of contour segments containing such points on the performance of contour based object recognition algorithms. We use complete contour representations of objects as a reference (training) set. Incomplete contour representations of the same objects are used as a test set. The performance of an algorithm is reported using the recognition rate as a function of the percentage of contour retained. We consider two types of contour incompleteness obtained by deletion of contour segments of high or low curvature. We illustrate the test procedure using two shape recognition algorithms that deploy a shape context and a distance multiset as local shape descriptors. Both algorithms qualitatively mimic human visual perception in that the deletion of segments of high curvature has a stronger performance degradation effect than the deletion of other parts of the contour. This effect is more pronounced in the performance of the shape context method.
PREDICTION BASED OCCLUDED MULTITARGET TRACKING USING SPATIO-TEMPORAL ATTENTION
Authors: LEE HEUNGKYU , KIM JUNE , KO HANSEOK
Published: September 2006

This paper proposes the prediction based occluded multitarget tracking method using spatio-temporal attention mechanism. To cope with occlusion between targets, the proposed method provides an efficient method for more complex analysis by combining object association with partial probability model in spatially attentive window and occlusion activity detection in predicted temporal location. While multiple objects are moving or occluding between them in areas of visual field, a simultaneous tracking of multiple objects tends to fail. This is due to the fact that incompletely estimated feature vectors such as location, color, velocity, and acceleration of a target can provide only ambiguous and missing information. Thus, the spatially and temporally considered mechanism is proposed to track each target before, during, and after occlusion. Robustness of the proposed method is demonstrated with representative simulations.
ENHANCED DIRECT LEAST SQUARE FITTING OF ELLIPSES
Authors: MAINI ELISEO STEFANO
Published: September 2006

This paper presents a robust and direct algorithm for the least-square fitting of ellipses to scattered data. The proposed algorithm makes use of well-known techniques that improve the robustness of the direct least-square fitting with a modest increase of the computational burden. Furthermore, by trivial modifications of the constrained minimization problem the algorithm may be converted to perform the specific fitting of other types of conics such as hyperbola. The method is simple and accurate and can be implemented with fixed time of computation. These characteristics coupled to its robustness and specificity makes the algorithm well-suited for applications requiring real-time machine vision.
CRITICAL SUCCESS FACTORS OF SIX-SIGMA IMPLEMENTATION: AN ANALYTIC HIERARCHY PROCESS BASED STUDY
Authors: LAOSIRIHONGTHONG TRITOS , RAHMAN SHAMS-UR , SAYKHUN KHAMMEE
Published: September 2006

Six-Sigma is a well-established and one of the most recognized approaches in manufacturing strategy development. Companies who have adopted and successfully implemented such a methodology were found to be more innovative which led to increased customer satisfaction and an improved bottom line. The aim of this study is to identify factors for successful Six-Sigma implementation by using the Analytic Hierarchy Process (AHP). The study involves four phases, which include: (1) assessment of potential factors and performance measures in Six-Sigma implementation (2) development of the problem structure and building the AHP model (3) soliciting and compilation of opinion on preferences through expert interviews, and (4) determination of critical success factors. Twenty-one experts, consisting of three-project champions and eighteen-black belts from five multinational companies located in Thailand, were interviewed. Expert Choice® software was used to compute the normalized and unique priority weights. The results of the data analysis determined the relative importance of individual factors, and in turn identified the critical factors on which organizations should consolidate their efforts in the process of implementing Six-Sigma methodology.
TECHNOLOGY MANAGEMENT TOOLS: GENERALIZATION, INTEGRATION AND CONFIGURATION
Authors: PHAAL ROBERT , FARRUKH CLARE , PROBERT DAVID
Published: September 2006

Managers in technology-intensive businesses need to make decisions in complex and dynamic environments. Many tools, frameworks and processes have been developed to support managers in these situations, leading to a proliferation of such approaches, with little consistency in terminology or theoretical foundation, and a lack of understanding of how such tools can be linked together to tackle management challenges in an integrated way. As a step towards addressing these issues, this paper proposes the concept of an integrated 'toolkit', incorporating generalized forms of three core technology management tools that support strategic planning (roadmapping, portfolio analysis and linked analysis grids).