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Population geneticists have often determined the fitness differences that account for the dynamics of naturally occurring genetic polymorphisms. However, to understand causal aspects of evolutionary processes requires, in addition, investigation of the physiological and molecular structural differences underlying adaptively significant genetic polymorphisms. The characteristics of the alcohol dehydrogenase gene--enzyme system in Drosophila melanogaster make it well suited for this kind of study. Natural populations of this species are polymorphic for two electrophoretically detectable variants, ADHF and ADHS, of the enzyme. Structural studies reported here reveal that the two variants differ by (at least) a single amino acid replacement, threonine in ADHF for lysine in ADHS.

A purification scheme for the cytoplasmic form of malate dehydrogenase (s-MDH) of Drosophila melanogaster is presented which is superior to any previously reported method. In addition, this scheme can also be used to obtain alcohol dehydrogenase (ADH) and FDP aldolase. Gel filtration experiments reveal an oligomeric molecular weight of 69,000 for s-MDH, and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate indicates subunit molcular weights of 32,100 for s-MDH, 24,600 for ADH and 34,000 for FDP aldolase. The amino acid composition of Drosophila melanogaster s-MDH and FDP aldolase are reported. © 1984.

The occupational therapist authors explored the evolution of co-occupation during their experiences of social distancing related to the COVID-19 pandemic and times of ongoing civil unrest. The research method used is auto-ethnography to describe and analyze their personal experiences juxtaposed with their cultural experiences. The authors, one white and one African American shared a desire to promote emotional and spiritual wellness during isolation, healthcare disparities, and social unrest. This collaboration led to a creative partnership aimed at promoting health and wellness for both themselves and sectors of their local African American spiritual community. Through designing, creating, giving, and receiving cycles, they worked cooperatively to interweave craftwork with social ministry. Intrigued by the traditions of African kente cloth, they designed and carried out a handwoven kente-style liturgical stole ministry focused on encouraging African American pastors who experienced difficulty engaging in their usual worship and fellowship, which serves as their respite from civil unrest and providing comfort during illness and death., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Autism spectrum disorder is an increasingly prevalent neurodevelopmental disorder in the world today, with an estimated 2% of the population being affected in the USA. A major complicating factor in diagnosing, treating, and understanding autism spectrum disorder is that defining the disorder is solely based on the observation of behavior. Thus, recent research has focused on identifying specific biological abnormalities in autism spectrum disorder that can provide clues to diagnosis and treatment. Biomarkers are an objective way to identify and measure biological abnormalities for diagnostic purposes as well as to measure changes resulting from treatment. This current opinion paper discusses the state of research of various biomarkers currently in development for autism spectrum disorder. The types of biomarkers identified include prenatal history, genetics, neurological including neuroimaging, neurophysiologic, and visual attention, metabolic including abnormalities in mitochondrial, folate, trans-methylation, and trans-sulfuration pathways, immune including autoantibodies and cytokine dysregulation, autonomic nervous system, and nutritional. Many of these biomarkers have promising preliminary evidence for prenatal and post-natal pre-symptomatic risk assessment, confirmation of diagnosis, subtyping, and treatment response. However, most biomarkers have not undergone validation studies and most studies do not investigate biomarkers with clinically relevant comparison groups. Although the field of biomarker research in autism spectrum disorder is promising, it appears that it is currently in the early stages of development., (© 2022. The Author(s).)

Aims: The purpose of this quantitative pilot study was to examine occupational therapy students' perceived value of a simulated learning experience and to identify various components of simulation that were valued., Methods: Students enrolled in an occupational therapy evaluation and intervention for the adult population course participated in a simulated experience using a standardized patient as part of course expectations. Participants completed an 18-item questionnaire following the simulation., Results: Students perceived simulated learning as a positive experience. The components identified as positive included feedback from the instructor, professional attire, consistent role of the standardized patient, and group debriefing after the simulation., Conclusion: Occupational therapy students perceived interaction with standardized patients as valuable. Further research is needed to analyze effectiveness of simulation in preparing occupational therapy and other healthcare students for actual clinical experience.

Background: Software applications (apps) could potentially promote exercise adherence. However, it is unclear whether adolescents with painful hyperkyphosis will use an app designed for a home exercise program. The purpose of this study is to assess factors regarding adherence to an app-based home exercise program in adolescents with hyperkyphosis and back pain who were provided a one-time exercise treatment., Methods: Twenty-one participants were instructed in a one-time exercise treatment and asked to complete a home exercise program 3 times a week for 6 months using an app called PT PAL. At a 6-month follow-up, 14 participants completed a survey assessing factors related to their experiences using the app and their treatment engagement., Results: Although most participants did not use the app, they reported performing their exercises a few times per week. The adolescent participants considered the app to be more of a barrier than a supportive measure for promoting exercise adherence. Most participants still reported bothersome back pain., Conclusions: Although adherence to the 6-month app-based home exercise program was not successful, adolescents still viewed technology support such as text reminders as a potential solution., Trial Registration: ClinicalTrials.gov Identifier: NCT03212664. Registered 11 July 2017. Retrospectively registered., Competing Interests: This study was approved by the Institutional Review Board of the primary investigator’s affiliated institute and registered with ClinicalTrials.gov. Prior to data collection, each adolescent participant’s assent and caregiver’s consent to participate in the study were obtained.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Aim: Increasing usage of cultural arts venues by children with special needs has created a need to optimize participation planning. A team of three occupational therapy graduate students and one faculty researcher was invited to provide a local children's theater staff with training for supporting children with special needs. The team aimed to determine how their collaboration with the theater could contribute to understandings of best practices in community participation planning., Method: The team participated in theater events, conducted a facility assessment, interviewed staff members with varying role responsibilities, and surveyed staff before and after conducting a participation-planning workshop., Results: The collaborative approach to participation planning utilized strategies that provided practical applications for theater staff, including planning for sensory processing and regulation challenges, and providing staff with behavior management and communication tips for interacting with children., Conclusion: Through training, staff participation planning evolved from reacting to present-day problems to proactively planning for future initiatives. Staff expressed desires to have some of their own members become in-house experts for participation planning, allowing others to pursue the theater's mission: providing live children's theater performances and programs.

Objectives: Reminiscing activity groups are commonly seen in various elder care settings This study addresses the impact of reminiscence activity groups, specifically a program where group members create their own mementos, on healthy Jewish elders' sense of satisfaction and meaning. In particular, this research focused on the specific factors involved in creating the mementos themselves., Method: In this mixed methods study, occupational therapy graduate students synthesized relevant aspects of commonly used activity analysis forms into a matrix to analyze the activities. From a pool of 30 activities, students chose seven representing many factors and levels of complexity. With a matrix composed of a Likert scale and open-ended questions, students and Jewish elders explored the elders' perceptions of factors significantly related to their experiences when creating the seven mementos., Results: Memento-making was most satisfying when elders were replicated in some way, such as with hand casting. Least satisfying activities were those that could lead to talents being appraised, such as painted self-portraits. Unanticipated factors such as social participation and educating others appeared to be as important as making the mementos themselves., Conclusion: While the research questions were partially answered, factors such as meaning and creativity were difficult constructs to measure because they lacked clear definitions. However, this preliminary exploration supports the concept that the use of an activity analysis matrix can enable activities directors and occupational therapists to systematically ascertain which factors positively impact well-being and social participation to meet the unique needs of aging client populations.

Edatrexate (10-ethyl-deazaaminopterin) is a methotrexate analog that has been shown to have greater antitumor activity and improved therapeutic index compared to its parent compound in preclinical systems. We have evaluated the ability of edatrexate to modulate the intrinsic resistance of the lung adenocarcinoma A549 cell line to carboplatin. Concentration effects, exposure time and schedule dependence were assessed. Modulation of resistance was observed with edatrexate treatment (0.2 microM for 1 h) prior to carboplatin. The concentrations of carboplatin to achieve IC50 at the 1-, 3-, and 24-h IC50 were decreased by a mean of 16.8 times (12.2-22.2) with edatrexate preexposure. In contrast, there was little modulation observed of carboplatin resistance when carboplatin was administered prior to edatrexate. In addition, schedule dependency experiments were performed using the method described by Chou and Talalay, in which the ratio of carboplatin to edatrexate was constant or nonconstant, and both the potency of effects and the shapes of the concentration-effect curves were taken into account in a computerized analysis. These experiments also demonstrated schedule dependency. Although both treatments resulted in a reduced IC50 vs. carboplatin alone, the reduction was much greater when edatrexate was added first (12.59 vs. 2.59 times). We conclude that the combination of edatrexate and carboplatin demonstrates schedule-dependent modulation of intrinsic carboplatin resistance in this in vitro model at clinically achievable edatrexate plasma levels (0.01 to 10 microM). The greatest modulatory synergism was observed in the setting of edatrexate treatment before carboplatin. Our findings suggest a potentially useful schedule when combining edatrexate and carboplatin for the treatment of malignant disease.

Transketolase (EC 2.2.1.1) is the enzyme that, together with aldolase, forms a reversible link between the glycolytic and pentose phosphate pathways. We have cloned and sequenced the transketolase gene from yeast (Saccharomyces cerevisiae). This is the first transketolase gene of the pentose phosphate shunt to be sequenced from any source. The molecular mass of the proposed translated protein is 73,976 daltons, in good agreement with the observed molecular mass of about 75,000 daltons. The 5'-nontranslated region of the gene is similar to other yeast genes. There is no evidence of 5'-splice junctions or branch points in the sequence. The 3'-nontranslated region contains the polyadenylation signal (AATAAA), 80 base pairs downstream from the termination codon. A high degree of homology is found between yeast transketolase and dihydroxyacetone synthase (formaldehyde transketolase) from the yeast Hansenula polymorpha. The overall sequence identity between these two proteins is 37%, with four regions of much greater similarity. The regions from amino acid residues 98-131, 157-182, 410-433, and 474-489 have sequence identities of 74%, 66%, 83%, and 82%, respectively. One of these regions (157-182) includes a possible thiamin pyrophosphate (TPP) binding domain, and another (410-433) may contain the catalytic domain.

A cDNA encoding rat cationic trypsinogen has been isolated by immunoscreening from a rat pancreas cDNA library. The protein encoded by this cDNA is highly basic and contains all of the structural features observed in trypsinogens. The amino acid sequence of rat cationic trypsinogen is 75% and 77% homologous to the two anionic rat trypsinogens. The homology of rat cationic trypsinogen to these anionic trypsinogens is lower than its homology to other mammalian cationic trypsinogens, suggesting that anionic and cationic trypsins probably diverged prior to the divergence of rodents and ungulates. The most unusual feature of this trypsinogen is the presence of an activation peptide containing five aspartic acid residues, in contrast to all other reported trypsinogen activation peptides which contain four acidic amino acid residues. Comparisons of cationic and anionic trypsins reveal that the majority of the charge changes occur in the C-terminal portion of the protein, which forms the substrate binding site. Several regions of conserved charge differences between cationic and anionic trypsins have been identified in this region, which may influence the rate of hydrolysis of protein substrates.

The currently available radioimmunoassays of trypsin measure total immunoreactive trypsin (EC 3.1.1.7), which includes both trypsinogen and alpha 1-protease inhibitor-bound trypsin. Hitherto, the only way to differentiate these two forms of trypsin has been to fractionate them on a gel-filtration column. We describe here a solid-phase immunoenzymometric assay that rapidly measures the amount of cationic trypsin bound to alpha 1-protease inhibitor in the plasma of rats with experimental pancreatitis. The assay specifically measures this complex within the range from 0.2 to 5.0 ng without interference by high concentrations of free alpha 1-protease inhibitor. The high correlation (r = 0.985) of the values obtained by size fractionation and by this assay demonstrates the accuracy of the assay, which is the first single-tube method for determining this form of activated cationic trypsin in plasma.

A cDNA encoding elastase 2 has been cloned from a human pancreatic cDNA library. The cDNA contains a translation initiation site and a poly(A) recognition site and encodes a protein of 269 amino acids, including a proposed 16-residue signal peptide. The amino acid sequence of the deduced mature protein contains a 12-residue activation peptide containing a cysteine at residue 1 similar to that of chymotrypsin. The proposed active enzyme contains all of the characteristic active-site amino acids, including His-57, Asp-102, and Ser-195. The S1 binding pocket is bounded by Gly-216 and Ser-226, making this pocket intermediate in size between chymotrypsins and elastase 1 or protease E, consistent with the substrate specificity of elastase 2 for long-chain aliphatic or aromatic amino acids. Computer modeling studies using the amino acid sequence of elastase 2 superimposed on the X-ray structure of porcine elastase 1 suggest that a change of Gln-192 in elastase 1 to Asn-192 in elastase 2 may account for the lower catalytic efficiency of the latter enzyme. In addition, modeling studies have been conducted to attempt to identify basic amino acids in elastases which are absent in chymotrypsins, and which could account for the specific property of elastolysis. Several basic residues appear to be near the ends of the extended binding pocket of elastases which might serve to anchor the enzyme to the elastin substrate. These studies indicate that elastases 2 and elastase 1 both contain an Arg-65A as well as a basic dipeptide at 223/224 which is not present in chymotrypsins.(ABSTRACT TRUNCATED AT 250 WORDS)

Previous studies have suggested that measurement of active enzymes in relation to proenzymes in serum of patients with pancreatitis may reflect the degree of zymogen activation in the gland. Here we describe the first single-tube assay for an active form of a pancreatic enzyme that is ordinarily synthesized as a proenzyme. Human procarboxypeptidase B, which we purified to near homogeneity, is approximately 13 000 Da larger than the active enzyme (EC 3.4.17.2). Antibodies specific for active carboxypeptidase B were obtained by affinity chromatography of anti-carboxypeptidase B antisera on a gel containing procarboxypeptidase B, then used to develop a single-tube radioimmunoassay for measuring active carboxypeptidase B in serum. Using this assay, we were able to detect, for the first time, active carboxypeptidase B in sera from patients with acute pancreatitis. Preliminary data show a correlation between the serum concentrations of active carboxypeptidase B and those of active trypsin complexed with serum inhibitors, but no correlation with serum amylase values.

Although protease E was isolated from human pancreas over 10 years ago [Mallory, P. A., & Travis, J. (1975) Biochemistry 14, 722-729], its amino acid sequence and relationship to the elastases have not been established. We report the isolation of a cDNA clone for human pancreatic protease E and determination of the nucleic acid sequence coding for the protein. The deduced amino acid sequence contains all of the features common to serine proteases. The substrate binding region is highly homologous to those of porcine and rat elastases 1, explaining the similar specificity for alanine reported for protease E and these elastases. However, the amino acid sequence outside the substrate binding region is less than 50% conserved, and there is a striking difference in the overall net charge for protease E (6-) and elastases 1 (8+). These findings confirm that protease E is a new member of the serine protease family. We have attempted to identify amino acid residues important for the interaction between elastases and elastin by examining the amino acid sequence differences between elastases and protease E. In addition to the large number of surface charge changes which are outside the substrate binding region, there are several changes which might be crucial for elastolysis: Leu-73/Arg-73; Arg-217A/Ala-217A; Arg-65A/Gln-65A; and the presence of two new cysteine residues (Cys-98 and Cys-99B) which computer modeling studies predict could form a new disulfide bond, not previously observed for serine proteases. We also present evidence which suggests that human pancreas does not synthesize a basic, alanine-specific elastase similar to porcine elastase 1.