[Examination of the relationship between tasks in geriatric health service facilities and benefits of working for older assistant care workers]

Objective　In this study, we clarified the characteristics of tasks performed by older assistant care workers at geriatric health services facilities, by individual characteristics and work status. Additionally, we examined the relationship between the tasks and benefits of working for older assistant care workers.Methods　A self-administered questionnaire survey was provided to 2,571 elderly care facilities employing assistant care workers aged ≥60.　A total of 1,606 responses were obtained, and personal characteristics, working conditions, tasks, and benefits of working for older care assistants were surveyed. Thirteen work tasks were established and categorized into four broad categories; user transfer assistance, facility maintenance, meal-related assistance, and managing and talking to users. Seven benefits of working as care assistants were "contribution to society," "social connection," "purpose of life," "income," "learning from caregiving," "health maintenance and promotion," and "time utilization."Results　Most of the respondents were women and relatively young workers. Among tasks, men, younger workers, and those working >5 days weekly represented a high proportion of those performing user transfer assistance tasks. Tasks on managing and talking to users were not correlated with sex, age, and number of days worked, but those with more flexible work patterns were more likely to be engaged in such tasks. Logistic regression analysis showed that user transfer assistance was correlated with benefits of working, such as "contribution to society," "social connection," and "learning from caregiving." Moreover, facility maintenance was associated with "income," "health maintenance and promotion," and "time utilization" and meal-related assistance was associated with "learning from caregiving." Managing and talking to users was associated with "contribution of society," "social connection," "purpose of life," and "learning from caregiving."Conclusion　The tasks of the workers were associated with individual characteristics and work status. The perception of benefits between the working tasks that involved frequent contact with users and those that did not were considerably different.

[Current conditions and challenges of employing older assistant care workers based on geriatric health services facilities' scale]

Objectives　To support care workers, some care facilities employ older individuals as care assistants for peripheral, non-professional tasks. However, the size of the facilities influences their employment needs and support systems for older care workers. Therefore, this study examined the rationale for employing older assistant care workers; the challenges they face; educational systems; and the efforts to facilitate continued employment based on facility size.Methods　Initially, a fax survey was conducted with 3,591 facilities associated with the National Association of Geriatric Health Services Facilities to determine the proportion of older assistant care workers employed. Thereafter, a questionnaire survey was administered to gather more information. Out of 3,591 facilities, 2,170 responded to the survey, and 1,261 responded to the questionnaire. In this study, care assistants aged ≥60 years were classified as older care assistants. The facilities were categorized based on admission capacity into two groups: "small/medium facilities" (≤99 residents) and "large facilities" (≥100 residents). A chi-square test was conducted for data analysis.Results　Of the all geriatric health services facilities, 31.7% employed older assistant care workers. Moreover, the questionnaire survey responses showed they are employed by 687 facilities. Further analysis revealed that larger facilities employed a higher number of older care assistants than small/medium facilities. Small/medium facilities tended to have fewer training systems for older care assistants than larger facilities (30.0% for small/medium facilities vs. 21.6% for large facilities; P=0.014). Furthermore, the work of older care assistants in small/medium facilities was more susceptible to family circumstances than those in larger facilities (15.7% for small/medium facilities vs. 10.2% for large facilities; P=0.033). Compared to small/medium facilities, larger facilities were more likely to state that their employment objective was to reduce the risk of care accidents (19.8% for small/medium facilities vs. 26.3% for large facilities; P=0.046) and provide psychological support, such as periodic interviews, to older care workers to ensure continued employment (24.1% for small/medium facilities vs. for large facilities 37.3%; P<0.001).Conclusion　Larger facilities employeda higher number of older care assistants than small/medium facilities. Furthermore, small/medium facilities were less likely to provide psychological support and had a less structured training system, compared to larger facilities. Additionally, the work of older care assistants in small/medium facilities was more susceptible to family circumstances and other factors, which could affect their work performance. Thus, developing adequate support systems in small/medium facilities is crucial to promoting the employment of older care assistants.

[Association between the change in the job facilitating and inhibiting factors of care staff due to the employment of older assistant workers and the emotional exhaustion among care staff]

Objectives　The mental health condition of care staff in Japan is becoming problematic. Older assistant workers are currently being employed to assist care staff with their jobs and alleviate their job burden. This employment of older assistant workers is drawing attention; however, their influence on the job facilitating and inhibiting factors of care staff and the association with the care staff's emotional exhaustion remains unclear. In this study, we aim to examine how the employment of older care assistant workers relates to the job-facilitating and job-inhibiting factors of care staff and explore that association with the care staff's emotional exhaustion.Methods　Data from a mail survey of geriatric health services facilities with older assistant workers were analyzed. Among the answers obtained from the care staff, answers from 5,185 who reported working in facilities that employ older assistant workers (over the age of 60) were analyzed. The Emotional Exhaustion subscale of the Japanese Version of the Burnout Questionnaire was used as the dependent variable. The change in job-facilitating and job-inhibiting factors of care staff due to the employment of older assistant workers (improve, maintain/exacerbate) was explored for nine contents.Results　Care staff reported a decrease in the total volume of the task (63.6%), less stress during daily tasks (39.8%), and more concentration on the tasks that require expert care knowledge (38.0%). The results of multiple regression analysis showed that the emotional exhaustion score of care staff was low when the total volume of tasks decreased (β=－0.383, 95%CI=－0.719, －0.047), when less stress was perceived during daily tasks (β=－0.432, 95%CI=－0.796, －0.068), when concentration on tasks that required expert care knowledge increased (β=－0.574, 95%CI=－0.937, －0.210), and when human relationships among staff improved (β=－0.871, 95%CI=－1.263, －0.480). Conversely, an increase in tasks requiring work with regional personnel and organizations (β=0.800, 95%CI=0.162, 1.437) was associated with a high emotional exhaustion score.Conclusion　The employment of older care workers was related to the job-facilitating or job-inhibiting factors of care staff, and the change in these factors was associated with lower emotional exhaustion. The employment of older personnel may lower the risk of burnout among care staff.

[Relationship between the perceived benefits of working and emotional exhaustion among older assistant care workers: A cross-sectional study]

Objectives　This study is intended to clarify the perceived benefits of working among older assistant care workers employed in geriatric health service facilities and examine the relationship between perceived benefits and emotional exhaustion.Methods　We analyzed data from a mail survey of older assistant care workers employed in geriatric health service facilities that the Japan Association of Geriatric Health Services Facilities conducted in 2020. In this survey, those aged ≥60 were defined as older assistant care workers. Responses were obtained from 1,606 older assistant care workers at 599 facilities. The dependent variable was the emotional exhaustion subscale of the Japanese version of the Burnout Questionnaire. The independent variables were the seven benefits of working as an assistant care worker: 1) I can contribute to society; 2) I am connected to society; 3) I have a sense of purpose in life; 4) I am earning the income I expected since I started working as an assistant care worker; 5) I am learning about care; 6) It has maintained and improved my health; and 7) I can use my time effectively. Latent class analysis (LCA) was performed using these seven benefits as independent variables. Multiple regression analysis was performed using emotional exhaustion and the perceived benefits as dependent and independent variables, respectively. The missing values were supplemented by the multiple imputation method.Results　Overall, 1,601 responses were analyzed after excluding 5 respondents who did not answer all the questions. Four patterns were identified from the LCA results: the "benefit-full type," who perceived all benefits; the "benefit-less type," who perceived few benefits; the "benefit-extroverted type," who perceived social contribution and connection as benefits; and the "benefit-introverted type," who perceived health maintenance and improvement and time utilization as benefits. The multiple regression analysis showed that emotional exhaustion scores were higher for the "benefit-extroverted" and "benefit-less" types than for the "benefit-full" type (b=2.465, P<.001 and b=1.931, P<.001, respectively). No difference was found in the case of the "benefit-introverted" type (b=0.050, P=.851).Conclusion　The perceptions of diverse and introverted benefits were associated with lower emotional exhaustion scores among older assistant care workers. Future intervention studies are needed to examine whether obtaining diverse or introverted benefits can decrease the emotional exhaustion score.

Older assistant workers in intermediate care facilities, and their influence on the physical and mental burden of elderly care staff

Background

As there is a shortage of care staff in elderly care homes, seniors are expected to work as assistants to help the care staff. This study examined the influence of older assistant workers in intermediate elderly care facilities on care staff, specifically focusing on emotional exhaustion which is a sign of burnout. These facilities provide long-term nursing and supportive care to older residents.

Methods

Data from a mail survey of intermediate elderly care facilities with older assistant workers were analyzed. Care staff were asked about the advantages and disadvantages of introducing older assistant workers in elderly care work, and their degree of emotional exhaustion. We also assessed work self-evaluations of older assistant workers, including the benefits of the work, and physical and mental burdens.

Results

A significantly large number of care staff reported improvements in workload with the employment of older assistant workers. Intermediate elderly care facilities enrolling more older assistant workers showed lower mean emotional exhaustion among care staff, independent of possible covariates. While older assistant workers felt that their work contributed to helping both care users and staff, they also reported a mental burden.

Conclusions

Our results suggest that older assistant workers can play a significant role in reducing the physical and mental burden of intermediate elderly care facility staff. Thus, employing older assistant workers can be an effective approach to addressing shortages of care staff in elderly care homes.

Enhanced Magnetic Interaction by Face-Shared Hydride Anions in 6H-BaCrO2H

Studies on magnetic oxyhydrides have been almost limited to perovskite-based lattices with corner-sharing octahedra with a M-H-M (M: transition metal) angle of θ ∼ 180°. Using a high-pressure method, we prepared BaCrO₂H with a 6H-type hexagonal perovskite structure with corner- and face-sharing octahedra, offering a unique opportunity to investigate magnetic interactions based on a θ ∼ 90° case. Neutron diffraction for BaCrO₂H revealed an antiferromagnetic (AFM) order at T_N ∼ 375 K, which is higher than ∼240 K in BaCrO_3-xF_x. The relatively high T_N of BaCrO₂H can be explained by the preferred occupancy of H^- at the face-sharing site that provides AFM superexchange in addition to AFM direct exchange interactions. First-principles calculations on BaCrO₂H in comparison with BaCrO₂F and BaMnO₃ further reveal that the direct Cr-Cr interaction is significantly enhanced by shortening the Cr-Cr distance due to the covalent nature of H^-. This study provides a useful strategy for the extensive control of magnetic interactions by exploiting the difference in the covalency of multiple anions.

Concrete with high-purity volcanic glass fine powder manufactured from pyroclastic deposit

Volcanic deposits, which are pozzolanically reactive, have long been known to improve the durability of concrete. Nevertheless, it has also been pointed out that the use of a natural pozzolan as a supplementary cementitious material (SCM) can pose problems of low workability and slow strength development. Also, in addition, its composition and physical properties have large variety and variability. We have been conducting studies on the total utilization of volcanic deposits for applications suitable for respective properties by classifying them by floating speed difference and particle diameter. It is reported that sorting out particles less than 2.4 g/cm3 by dry gravity classification and removal of smaller clay fraction by dust collector is technically effective to recover high purity volcanic glass from pyroclastic flow deposits called “Ito-Shirasu”, which is a local name for pyroclastic flow deposits in Japan. In this study, concrete containing high-purity volcanic glass powders with different finenesses are investigated regarding fresh properties, strength development, chloride ion penetration and CO2 reduction. As a result, it was found that volcanic glass powders made an excellent contribution to the improvement of flowability comparable to fly ash, the enhancement of strength comparable to silica fume, and the restraint of chloride ion penetration. Volcanic glass powders can also contrbute to the reduction of CO2 emission because the content of Portland cement can be significantly reduced to obtain the same strength compared to concrete with 100% Portland cement. This study provides a possibility to produce high performance SCMs in volcanic regions worldwide from volcanic ejecta by sorting out a high purity volcanic glass by the same method.

Probucol Slows the Progression of Cataracts in Streptozotocin-Induced Hyperglycemic Rats

We examined the effect of probucol, an antihyperlipidemic drug with potent antioxidant properties, on cataract formation in streptozotocin (STZ)-induced hyperglycemic rats that were given 5% D-glucose as drinking water. Probucol treatment was initiated immediately after the induction of hyperglycemia was confirmed. Using full horizontal-plane lens images captured with an original digital camera system, the opacity of central region of lens was assessed by measuring the opaque area in the region. Central opacities were detected after 3 weeks of hyperglycemia, and progressed in a time-dependent manner. The majority of STZ-induced hyperglycemic rats developed severe cataracts after 9 weeks of hyperglycemia. Probucol slowed the progression of cataracts in a dose-dependent manner. Levels of sorbitol and protein carbonyls in lenses of STZ-induced hyperglycemic rats were higher than those of control rats. Probucol suppressed the increase in protein carbonyls, but not of sorbitol, in lenses of STZ-induced hyperglycemic rats. Probucol had no significant effect on increases in plasma concentrations of glucose, total cholesterol, and triglyceride observed in STZ-induced hyperglycemic rats. These results suggest that probucol slows the progression of sugar cataracts, independent of its lipid-lowering effects. The beneficial effect of probucol on cataracts is partially attributable to the attenuation of oxidative damage to lens proteins.

Anti-cataract Effect of Resveratrol in High-Glucose-Treated Streptozotocin-Induced Diabetic Rats

Resveratrol, which is a polyphenol found in grapes, peanuts, and other plants, has health benefits for various chronic diseases. The aim of the present study was to examine the effect of resveratrol on cataract formation in diabetic rats. Male Wistar rats (7-week-old) were treated with streptozotocin, and the streptozotocin-treated animals were administered 5% D-glucose in drinking water to promote the formation of cataracts by inducing severe hyperglycemia. Resveratrol supplementation (10 or 30 mg/kg/d) in drinking water was initiated immediately after induction of diabetes was confirmed. The full lens images of the horizontal plane were captured with the digital camera system which we developed. Cataract formation was assessed by an observer-based scoring method and by quantitative analysis of digital images of the lens. Cataracts at the peripheral region of the lens were detected 2 weeks after induction of hyperglycemia and progressed depending on the length of the diabetic period. The majority of them developed severe cataracts after 9 weeks of hyperglycemia. Resveratrol did not prevent the appearance of diabetic cataracts but significantly delayed the progression of cataracts compared with controls. The contents of sorbitol and protein carbonyls in lenses of diabetic rats were higher than those of control rats. Resveratrol suppressed the increase in protein carbonyls, but not of sorbitol, in diabetic lenses. These results suggest that resveratrol delays the progression of diabetic cataracts partially through attenuation of oxidative damage to lens proteins. Resveratrol may be beneficial in preventing the progression of diabetic cataracts.

Microbes Culture System Using Cellulose Tubes and Photocatalyst-Coated Glass Balls

Currently, microbes are utilized in many fields, such as medicine, food and environment etc. For more application of microbes, we need a new culture system, which can culture target microbes in large quantities at low cost. Thereupon, we propose a culture system using cellulose tubes. Target microbes are encapsulated inside the cellulose tubes, where they acquire nutrients and oxygen through nano pores of the tubes and are protected from competitive microbes even in open environment. To further increase the amount of oxygen and nutritions available for the target microbes, we propose photocatalyst-coated glass balls (PCGB) to sterilize competing microbes outside the tubes. We experimentally verified the effectiveness of the proposed culture system by culturing Coryne gultamicum as the target microbes.

Micro-tube mass production device for microbial culture

This paper describes mass production system of micro-tubes for microbial culture in an open environment. Microbes are used in many fields, such as food, medicine, environmental and energy. We proposed a microbe culture system using hydrogel micro-tubes, which can protect the target microbes inside from competitive microbes outside of the tubes while allow oxygen and nutrition to diffuse through. The hydrogel micro-tubes can be produced by a microfluidic device, which can precisely control the flow and therefore, the tube geometry. For practical applications of the micro-tube-based microbial culture, one of the biggest challenges is the scale-up of the micro-tube-based culture system, or mass production of the tubes. We developed a fluidic system that can produce multiple micro-tubes in parallel. We characterized the mass-produced micro channels and verified the effectiveness of the system.

A simple method for micropatterning nanofibrous hydrogel film

This paper propose a new fabrication process for micropatterning a nanofibrous thin film made of bacterial cellulose(BC). BC is a hydrogel produced by specific bacteria and composed of pure cellulosic nanoflbers exhibiting 3D network structure. Such nanofibrous structure is found to be appropriate for adhesion of anchorage-dependent cells. Furthermore, BC shows high biocompatibility and mechanical toughness. Thus, the microfabrication technique for BC broadens potentials for applications. In this study, we report a new method for micropatterning BC film with feature resolution comparable with photolithography technology.

Toad's egg-like cultivation process for forming microcarriers from nanofibrous hydrogel

This paper proposes a new method for generating microcarries from bacterial cellulose (BC). BC, which is produced by specific bacteria, is a hydrogel composed of a three dimensional network structure formed by cellulose nanofibers. BC as an ECM-like nanofibrous material exhibits an excellent environment for cellular adhesion. Moreover, BC has a high biocompatibility and mechanical strength. From these properties, BC is expected to be applied for microcarriers, which is used for cultivating anchorage-dependent cells. Then, we developed a microfabrication process to create BC microcarriers by using gelatin microspheres as sacrificial architectures. In addition, the monodispersity of the formed BC microcarreirs was investigated.

Development of hydrogel microtubes for microbe culture in open environment

This paper describes a microbe culture system in an open environment using hydrogel microtubes. In recent years, oil production microbes, such as Aurantiochytrium, have been found and are studied to produce fuels of new age instead of fossil fuels. Biomass production by microbes is promising, where scale-up, collection of the products and competition against other microbes are the most important challenges. Here, we propose to use hydrogel microtubes to encapsulate, culture, and protect microbes. The tubes can be micro- and mass-fabricated. They allow oxygen and nutrition to go through while they prevent competitive microbes from intruding inside. The microbes and byproducts can be collected together with the tubes. In this paper, we demonstrate the proof-of-concepts experiments: we fabricated hydrogel micro tubes and cultured Coryne glutamicum which produce lactic acid inside the tubes. The microbes were increased inside the tubes and protected even when competitive microbes existed in the culture media. Furthermore, we demonstrated how to collect microbes inside the tubes.

[Development of a staging classification for leisure activities and social communication in dependent elderly persons]

AIM

The aim of this study was to develop a simple staging classification to measure leisure activity and social communication among the elderly at geriatric health care facilities.

METHODS

In order to construct a staging scale for measuring the participation of the elderly subjects, we developed a list of 28 items for three domains: leisure activities, social participation and communication. Data were obtained from users of institutional and day care services at geriatric health service facilities. The Rasch model was applied to test the degree of item fit and difficulty. Simple staging scales were constructed based on 12 leisure activity and nine social communication items. The validity and reliability were tested using these newly developed scales according to the Rasch model and assessments of the test-retest reliability.

RESULTS

The participants were 3,458 elderly persons, of whom 1,560 were currently using institutional services and 1,898 were using day care services. Among the 28 items, "traveling" was identified as the most difficult and "watching television" was identified as the easiest. Because items related to "social participation," such as volunteer activities, exhibited a low frequency, they were not used in the further analyses. Simple staging scales were constructed by analyzing the remaining items of leisure activities and social communication according to the Rasch model. The thresholds within the scales were determined in order of item difficulty. Cohen's kappa, as assessed by two different evaluators, was 0.75 for leisure activities and 0.77 for social communication.

CONCLUSIONS

In this study, we developed staging scales for leisure activity and social communication. The construct validity and test-retest reliability were adequate for both scales. Service providers can improve service quality by using these scales for individual case management of elderly persons in conjunction with existing scales of activities of daily living.

Altered expression of dermokine in skin disorders

BACKGROUND

Although dermokine-β, a glycoprotein expressed in epithelial cells, does not have significant homology to other proteins, its carboxyl-terminal domain shares a high pI value with many cytokines, suggesting similar functions.

OBJECTIVE

To better understand the biology of dermokine, we here determined its localization under pathological conditions and examined factors that regulate its expression.

METHODS

We generated an anti-human dermokine-β/γ monoclonal antibody cross-reacting with the mouse protein. Using this antibody, immunohistological staining and Western blotting of dermokine-β/γ were performed with various tissue samples.

RESULTS

Although human dermokine-β/γ was expressed in almost all granular layers, upper spinous layers of the skin were also stained with anti-dermokine-β/γ antibody in inflammatory skin disorders. Dermokine-β/γ was expressed in keratoacanthoma and a part of well-differentiated squamous cell carcinoma (SCC). However, dermokine-β/γ was not detected in poorly differentiated SCC or tumours derived from non-keratinocytes. In mice, dermokine-β/γ-expressed keratinocytes were increased in models of contact hypersensitivity, ultraviolet-irradiated skin injury and wound healing. Consistent with expanded distribution in inflammatory skin diseases, proinflammatory cytokines such as interleukin-1β, interleukin-12, and tumour necrosis factor-α augmented dermokine-β/γ expression in cultured human keratinocytes. In contrast, growth factors including epidermal growth factor, insulin-like growth factor-I, keratinocyte growth factor and transforming growth factor-α significantly reduced dermokine expression.

CONCLUSION

These results provide novel insights into the physiological and pathological significance of dermokine in the epidermis.

Instability of Superplastic Aluminium Alloys

The influence of the strain hardening coefficient,γ,and the strain rate sensitivity exponent, m, on the onset and growth of necking has been pointed out in many models about plastic instability controlled by the mechanical properties of materials. In this paper, the instability parameter I (=(l-γ-m)/m) proposed by Hart is used to relate the values of m (=∂lnσ/∂lnέ) and γ (=∂σ/(σ·∂ε)) for some superplastic aluminium alloys. These values of m and γ were calculated from the load-elongation curve at various strain-rates in constant strain-rate tests with periodic m determinations by strain-rate departures of small magnitude. It will be shown that the strain hardening due to grain growth contributes to an increase in the stability of plastic deformation during superplastic flow. However the decrease of m due to dynamic grain growth with strain causes superplastic deformation to be unstable near the onset of fracture. The transition of I values from negative to positive coincides with a decrease in m value and flow stress.

It is concluded that the development of necks can be characterized by an instability parameter I which include the effect of strain hardening caused by strain induced grain growth.

Superplasticity in P/M Aluminium Alloys

Recent advances in the technologies of powder metallurgy lead to the development of some superplastic aluminium alloys containing a deliberate addition of a large amount of Zr and /or Cr and Mn that exhibit the high strain rates superplasticity. For a few alloy systems, the large elongation more than 500% has been observed over the strain rates of 1×10−1s−1, which rates are two or three orders of magnitude faster than those at which superplasticity is found in conventional superplastic aluminium alloys produced by ingot metallurgy. The high strain-rates superplasticity obtained in both type of fully static recrystallized and dynamic recrystallized P/M aluminium alloys. The decreasing of initial size of grains and/or sub-grains leads to the increasing the strain-rates for superplastic flow in both types of alloys. The refinement of grains or sub-grains size is one of necessary and important to obtain the high strain-rates superplasticity.

Japanese collaborative study to assess inter-laboratory variation in factor VII activity assays

BACKGROUND

The clinical phenotype manifest by patients with factor VII (FVII) deficiency correlates poorly with that predicted by laboratory tests. Despite its importance, there are no data on the variability of inter-laboratory determinations of low to very low plasma FVII activity (FVII:C).

METHODS

We distributed three FVII-deficient plasma samples, prepared by immunoaffinity chromatography, to 58 laboratories in Japan. All samples were assayed using standardized reference plasma as a calibrator. Recombinant thromboplastin was also supplied as a common reagent.

RESULTS

In the case of sample A, which had a very low FVII:C, the use of standardized reference plasma and thromboplastin, lowered the variability of inter-laboratory measurements, when compared with the variability observed when samples were assayed using the respective laboratory's routine method.

CONCLUSIONS

The data obtained indicated that results for samples with a very low FVII:C were greatly influenced by the number of plasma dilutions used in constructing a standard activity curve, and also by the type of calibrator and thromboplastin. Such variability was not seen for samples with moderate FVII:C. We conclude that it is necessary to develop a more sensitive and accurate FVII:C measurement system for the diagnosis and treatment of FVII deficiency.

Japanese collaborative study for fibrinogen assay: variability of the fibrinogen assay between different laboratories does not improve when a common calibrator is used

Several national and local external quality assurance schemes have been developed to improve the plasma fibrinogen assay in Japan over the past 30 years. Now most commercial calibrant plasma may be calibrated against an International Standard preparation, in order to achieve agreement of results obtained by different laboratories. However, we have never achieved satisfactory results, according to an external quality control survey regarding the fibrinogen assay. Therefore, we distributed two kinds of fibrinogen standards to be used as common calibrators, along with three plasma samples, among 183 general laboratories in Japan. The results of this collaborative study showed that the assigned value for the commercially available calibrators remained problematic. Furthermore, it was concluded that the between-laboratory variability could not be improved beyond a certain degree of standardization, even if a common calibrator was used for the Clauss-derived assay carried out by an automatic coagulometer.

Identification of a novel gene family, paralogs of inhibitor of apoptosis proteins present in plants, fungi, and animals

Only few orthologs of animal apoptosis regulators have been found in plants. Recently, the ectopic expression of mammalian inhibitor of apoptosis proteins (IAPs) has been shown to affect plant programmed cell death. Here, we identified two novel proteins homologous to Arabidopsis thaliana IAP-like protein (AtILP) 1 and 2 by applying an improved motif searching method. Furthermore, homologs of AtILP1 were found to occur as a novel gene family in other organisms such as fungi and animals including Homo sapiens (HsILP1). Like baculovirus IAP repeats (BIRs) in IAPs, ILPs contain two highly conserved BIR-like domains (BLDs) with a putative C2HC-type zinc finger. Phylogenetic analyses indicated that ILPs are putative paralogs of IAPs. Homology modeling revealed that the three-dimensional structure of BLD in HsILP1 is similar to that of BIR. Transient expression of HsILP1 resulted in inhibition of etoposide-induced apoptosis in HEK293 and HeLaS3 cells. These findings suggest that ILPs are conserved in a wide range of eukaryotes including plants, and that their functions are closely related to those of IAPs.

Characterization of hypervariable region in hepatitis C virus envelope protein during acute and chronic infection

Hepatitis C virus (HCV) causes persistent infection in most patients. To clarify the mechanisms underlying establishment of this persistent infection, nucleotide sequences of the E1/E2 region were characterized in 5 patients with acute and chronic HCV infection. We used direct DNA sequencing methods to identify the major sequence of HCV in each patient. Each HCV genome displayed a high frequency of nucleotide sequence variation in the hypervariable region (HVR) of E2. However, patient-specific conserved nucleotide sequences were identified in the E1/E2 region during the course of infection and conserved the higher-order protein structure. In the acute phase HCV infection, amino acid substitution in HVR-1 as the monthly rate of amino acids substitution per site (%) between each point exceeded 10.2%. In the chronic phase HCV infection, a significantly lower rate of amino acid substitution was observed in patients. The host immune responses to HVR-1 of each HCV isolates from all clinical courses were characterized using synthetic peptides and ELISA. One chronic patient serum (genotype 1b) did not react at all to its own HVR-1 peptides, however another patient (genotype 2b) reacted to all clinical course. These results indicated that HVR-1 might not always exhibit neutralizing epitopes of HCV infection. The sequence variation in HVR-1 may instead indicate the existence of various clones in acute phase infection and the adaption of these clones is thought to have caused persistent and chronic infection in each patient.