Bidirectional Association between Visual Impairment and Dementia Among Older Adults in the United States Over Time

PURPOSE

Although visual impairment (VI) has been associated with worse cognitive performance among older adults, the temporal relationship between the 2 remains subject to debate. Our objective was to investigate the longitudinal impact of VI on cognitive function and vice versa.

DESIGN

Retrospective, time-to-event study.

PARTICIPANTS

National Health and Aging Trends Study (NHATS) participants from 2011 to 2018 cycles.

METHODS

A total of 10 676 participants aged 65 years and older were included. Cox proportional hazards regression models evaluated the impact of baseline VI on subsequent dementia and impact of baseline dementia on subsequent VI. Models were adjusted for potential confounding variables, including demographics, clinical comorbidities, and hearing and physical function limitations.

MAIN OUTCOME MEASURES

Hazard ratio (HR) for incident dementia among participants with baseline self-reported VI and HR for incident VI among participants with baseline dementia.

RESULTS

Of the 10 676 participants included in the analysis, approximately 40% were aged 65-74 years, 40% were aged 75-84 years, and the remaining 20% were aged 85 years and older. The majority were female (59%), and 68% self-identified as non-Hispanic White. Among participants with normal cognitive status at baseline, subsequent dementia was observed in 1753 (16%), and among participants with normal self-reported vision at baseline, subsequent VI was reported in 2371 (22%). In adjusted regression models, participants with baseline VI had higher likelihood of developing dementia over subsequent follow-up (HR, 2.3; 95% confidence interval [CI], 2.0-2.6; P < 0.001). Likewise, participants with baseline dementia had a higher likelihood of developing self-reported VI over time (HR, 2.5; 95% CI, 2.2-2.8; P < 0.001).

CONCLUSIONS

Self-reported VI in the US Medicare population is associated with greater dementia likelihood over time, and dementia is similarly associated with greater VI likelihood over time. Associations are likely multifactorial and bidirectional and could be explained by intervening variables in the path from VI to dementia, or vice versa, or by common risk factors for pathological processes in both eyes and brain. These findings suggest the need for early identification of older adults with visual compromise and consideration of visual disability in the cognitively impaired.

Resident-performed immediate sequential bilateral cataract surgery during the COVID-19 pandemic

Purpose:

To assess visual outcomes and patient satisfaction for senior resident-performed immediate sequential bilateral cataract surgery (ISBCS) versus delayed sequential bilateral cataract surgery (DSBCS) during the COVID-19 pandemic, when minimizing healthcare-related exposures for patients and providers are paramount.

Methods:

This was a pilot retrospective cohort study of all ISBCS and DSBCS patients who underwent senior resident-performed cataract surgery from May to September 2020 at a single academic institution. Outcome measures were final corrected distance visual acuity (CDVA), final manifest refraction (MRx), intraoperative and postoperative complications rates, total number of visits, and patient satisfaction assessed postoperatively by telephone questionnaire.

Results:

Twenty-two eyes of 14 patients and 56 eyes of 28 patients underwent senior resident-performed ISBCS and DSBCS, respectively. Final CDVA was 20/25 or better in 21 (95%) ISBCS and 51 (91%) DSBCS eyes (P = 0.670). Deviation of final MRx from target refraction was within 0.50 D in 17 (77%) ISBCS and 47 (84%) DSBCS eyes (P = 0.522). There was no significant difference in intraoperative (P = 1.000) or postoperative (P = 1.000) complications. ISBCS patients averaged 3.5 fewer visits than DSBCS patients (5.9 vs 9.5, P < 0.001). All ISBCS and 20 DSBCS patients (87%) reported they were “very satisfied” or “satisfied” with their experience (P = 0.701). Five of six senior residents responded that they preferred performing ISBCS over DSBCS.

Conclusion:

This early experience suggests that senior resident-performed ISBCS is as safe and effective as DSBCS, with the added benefit of averaging fewer in-person visits. Residency programs should consider offering senior resident-performed ISBCS to select patients during the COVID-19 pandemic.

Elevated Serum FGG Levels Prognosticate and Promote the Disease Progression in Prostate Cancer

Castration-resistant prostate cancer (CRPC) threatens the health of men in general and no effective therapeutics currently exists for the treatment of CRPC. It is therefore of great importance to find a novel molecule that can be a biomarker and a therapeutic target for CRPC. First, we found that the serum fibrinogen gamma (FGG) levels in patients with CRPC were significantly higher than those with localized prostate cancer (PCa) through iTRAQ proteomics and ELISA experiments. Immunohistochemistry, quantitative real-time polymerase chain reaction and western blot also showed an increase of FGG expression in CRPC tissues and cells. Then we proved the proliferation, invasion and migration ability of CRPC cells were significantly reduced after FGG knockdown. The number of apoptotic cells increased at least sixfold after FGG silencing, and was observed in conjunction with an upregulation of p53, caspase 3, clea-caspase 3, and Bax, and a downregulation of Bcl2 and survivin. FGG knockdown in DU145 cells resulted in smaller xenografts than control cells in a mouse model. and we established that FGG is modulated by IL-6 which was increased in CRPC patients via phosphorylation of STAT3. The data suggests that FGG may be a potential therapeutic target and prognostic marker for CRPC.

[Comparison on short-term safety outcomes between off-pump and on-pump coronary artery bypass grafting by experienced surgeons: a single center study with 31 075 cases]

Objective: To compare the short-term outcomes between off-pump and on-pump coronary artery bypass graft (CABG) by experienced surgeons with similar surgical team in a single large-volume cardiac surgery center. Methods: A total of 31 075 patients with multivessel coronary disease who underwent isolated off-pump or on-pump CABG between January 1, 2009 and December 31, 2019 by experienced surgeons in Fuwai hospital were enrolled in this retrospective study. Patients was divided into on-pump CABG group and on-pump CABG group on an intention-to treat basis. Short term safety endpoints, including 30 days mortality, composite endpoint of major morbidity or mortality, prolonged postoperative length of stay (PLOS), and prolonged ICU length of stay (PICULOS), and distal anastomosis were compared between the two groups. Mortality was evaluated on 30 days post operation, other endpoints were collected before discharge. After 1∶1 propensity-score matching of baseline characteristics for on-pump and off-pump CABG, postoperative endpoints were compared with use of McNemar's test and further adjusted with the use of a logistic regression model. Results: After propensity-score matching, 10 243 matched pairs of patients were included in the final analysis, there were 4 605(22.5%) females and mean age was (60.7±8.6) years. The standardized differences were less than 5% for all baseline variables in matched cohort. Univariate analysis indicated lower risk of 30 days mortality (0.2% vs. 0.7%, P<0.001), major morbidity or mortality (5.7% vs. 8.8%, P<0.001), PLOS (3.2% vs. 4.9%, P<0.001), PICULOS (9.4% vs. 12.2, P<0.001), and lower number of distal anastomosis ((3.3±0.8) vs. (3.6±0.8), P<0.001) in off-pump CABG group than in on-pump CABG group. After adjustment of cofounders, multivariate analysis showed that off-pump CABG was still associated with a lower risk of 30 days mortality (OR=0.29, 95%CI: 0.09-0.87, P=0.027), composite endpoint of major morbidity or mortality (OR=0.60, 95%CI: 0.53-0.68, P<0.001), PLOS (OR=0.64, 95%CI 0.54-0.75, P<0.001), PICULOS (OR=0.76, 95%CI: 0.69-0.84, P<0.001). Conclusions: Off-pump CABG is related with superior short-term safety outcomes than on-pump CABG by experienced surgeons in our center.

[Cathepsin L mediates glomerular endothelial cell injury by cleavaging complement C3 in trichloroethylene-sensitized mice]

Objective: To observe the expressions of complement 3 (C3) and endothelial cell injury-associated proteins before and after cathepsin L (CTSL) blockade in renal injury of trichloroethylene (TCE) -sensitized mice. Methods: In June 2018, 41 SPF female BALB/c mice were divided respectively into blank control group (n=5) , vehicle control group (n=5) , TCE group (n=15) and TCE+CTSLi group (n=16) to establish trichloroethylene-sensitized mice model by pretreating the mice with intraperitoneal injection of CTSL inhibitor (CTSLi) and using TCE for the first and last challenge. According to the skin sensitization score, the mice were divided into positive group and negative group. 72 hours after the last challenge, the renal function indexes of the mice were detected, the pathological changes of mice kidneys were observed, and the glomerular C3 and endothelial cell damage-related proteins [vascular cell adhesion molecule 1 (VCAM-1) , tight junction protein 5 (Claudin-5) and Syndecan-1] expression levels were detected. Results: The sensitization rates of mice in TCE group and TCE+CTSLi group were 53.3% (8/15) and 50.0% (8/16) , respectively, and there was no significant difference between the two groups (P>0.05) . Compared with vehicle control group and the corresponding TCE negative group, the serum creatinine (CRE) and blood urea nitrogen (BUN) levels of mice in the TCE positive group was increased, while the TCE positive group were higher than the TCE+CTSLi positive group (P<0.05) . Pathological examination showed obvious vacuolar degeneration and cellular edema in the mice kidney of the TCE positive group. In the TCE+CTSLi positive group, the above pathological damage was significantly improved. Immunohistochemical results showed that the expression of glomerular C3 fragment and VCAM-1 in TCE positive group were significantly higher than that of the vehicle control and TCE negative group (P<0.05) , while TCE+CTSLi positive group was significantly lower than that of TCE positive group (P<0.05) . Western blot test results showed that the relative expression levels of Claudin-5 and Syndecan-1 protein in the mice glomeruli of TCE positive group were significantly lower than those in the vehicle control group and TCE negative group (P<0.05) . Compared with the TCE positive group, the Claudin-5 protein was increased in the kidney of the TCE+CTSLi positive group, but the difference was not statistically significant (P>0.05) , while the Syndecan-1 protein was significantly increased in the TCE+CTSLi positive group (P<0.05) . Conclusion: CTSL may mediate the glomerular structural damage by cutting complement C3, activating the complement system, damaging endothelial cell structural protein Syndecan-1 and overexpressing adhesion molecule VCAM-1 in TCE-sensitized mice. Inhibiting the expression of CTSL may be an effective way to protect the glomerular integrity of structure and function in pharmacology.

Characteristics of cataract surgery patients influencing patient satisfaction scores

PURPOSE

To determine factors that influence patient satisfaction scores in individuals who have recently had cataract surgery.

SETTING

Byers Eye Institute, Palo Alto, California, USA.

DESIGN

Prospective case series.

METHODS

Selected questions from the Press Ganey survey and the National Eye Institute Visual Function Questionnaire-25 were administered to each patient immediately after completion of a clinic visit. The correlation between patient-specific variables and the answer to the survey question "likelihood of recommending our practice to others," a surrogate for overall patient satisfaction, was assessed using the Student t test. A logistical regression model was used to adjust for potentially confounding variables.

RESULTS

One hundred forty-three patients were recruited from 4 providers; 57 (39.8%) were men, and the mean age was 70.0 years ± 11.6 (SD). The main outcome was the proportion of scores less than 5, or "very good," for the likelihood of recommending the practice to others. There was a statistically significant association between a non-5 patient satisfaction score and self-reported ethnicity of Asian or Pacific Islander compared with other ethnicities (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.0-5.1; P = .049); other possible correlates were not statistically significant. The relationship persisted after adjustment for potential confounding variables (OR, 2.6; 95% CI, 1.1-6.3; P = .027).

CONCLUSION

In postoperative cataract patients, Asian or Pacific Islander ethnicity, a factor out of the control of the provider and clinic staff, was associated with a lower overall Press Ganey patient satisfaction score compared with patients of all other ethnicities.

[Mode of median nerve irritation under different wrist forcing postures observed by ultrasonography and foot pressure measurement system]

Objective: To analyze the influence of simulation mouse use motion under different wrist forcing postures on median nerve, tendons and ligaments in the carpal tunnel. Methods: From June to November in 2017, a total of 49 healthy volunteers [aged from 18 to 27 years, 24 males (48 cases of hands) and 25 females (50 cases of hands)] were selected in the Institute of Digitized Medicine and First Affiliated Hospital of Wenzhou Medical University.Three hand postures of the volunteers were simultaneously and continuously measured by using LOGIQ E9 ultrasonic diagnostic apparatus and Zebris foot pressure distribution measurement system.Seventeen parameters of nerves, tendons and ligaments in carpal tunnel were observed under natural (0 N), and two forced (25 and 50 N) states.Double factor variance analysis was performed with generalized estimating equation (GEE). Results: With increasing pressure (0, 25 and 50 N) of hand postures, the distance between median nerve and transverse carpal ligament were all less than 0.2 cm.The differences in both the distance between median nerve and flexor pollicis longus under the hand pressure changes or under the hand posture changes and the top angle of a triangle composed of median nerve, flexor pollicis longus and flexor digitorum superficialis group under the hand pressure changes or under the hand posture changes were all significant under the GEE analysis (all P<0.01). There were no significant changes in all other structural parameters in the carpal tunnel with the increasing of hand pressure (all P>0.05). Conclusions: The influence of the transverse carpal ligament to the median nerve belongs to the mechanism of pressure-induced irritation damage.The influence of flexor pollicis longus to median nerve belongs to the mechanism of tension-induced irritation damage.The influence of flexor digitorum superficialis to median nerve belongs to the mechanism of mixed shear irritation damage.

Association of Vision Loss With Cognition in Older Adults

Importance

Visual dysfunction and poor cognition are highly prevalent among older adults; however, the relationship is not well defined.

Objective

To evaluate the association of measured and self-reported visual impairment (VI) with cognition in older US adults.

Design, Setting, and Participants

Cross-sectional analysis of 2 national data sets: the National Health and Nutrition Examination Survey (NHANES), 1999-2002, and the National Health and Aging Trends Study (NHATS), 2011-2015. The NHANES was composed of a civilian, noninstitutionalized community, and the NHATS comprised Medicare beneficiaries in the contiguous United States. Vision was measured at distance, near, and by self-report in the NHANES and by self-report alone in the NHATS. Sample weights were used to ensure result generalizability.

Main Outcomes and Measures

The NHANES measured Digit Symbol Substitution Test (DSST) score and relative DSST impairment (DSST score ≤28, lowest quartile in study cohort), and the NHATS measured probable or possible dementia, classified per NHATS protocol.

Results

The NHANES comprised 2975 respondents aged 60 years and older who completed the DSST measuring cognitive performance. Mean (SD) age was 72 (8) years, 52% of participants were women (n = 1527), and 61% were non-Hispanic white (n = 1818). The NHATS included 30 202 respondents aged 65 years and older with dementia status assessment. The largest proportion (40%; n = 12 212) were between 75 and 84 years of age. Fifty-eight percent were women (n = 17 659), and 69% were non-Hispanic white (n = 20 842). In the NHANES, distance VI (β = -5.1; 95% CI, -8.6 to -1.6; odds ratio [OR], 2.8; 95% CI, 1.1-6.7) and subjective VI (β = -5.3; 95% CI, -8.0 to -2.6; OR, 2.7; 95% CI, 1.6-4.8) were both associated with lower DSST scores and higher odds of DSST impairment after full adjustment with covariates. Near VI was associated with lower DSST scores but not higher odds of DSST impairment. The NHATS data corroborated these results, with all vision variables associated with higher odds of dementia after full adjustment (distance VI: OR, 1.9; 95% CI, 1.6-2.2; near VI: OR, 2.6; 95% CI, 2.2-3.1; either distance or near VI: OR, 2.1; 95% CI, 1.8-2.4).

Conclusions and Relevance

In a nationally representative sample of older US adults, vision dysfunction at distance and based on self-reports was associated with poor cognitive function. This was substantiated by a representative sample of US Medicare beneficiaries using self-reported visual function, reinforcing the value of identifying patients with visual compromise. Further study of longitudinal interactions between vision and cognition is warranted.

Use of phosphodiesterase inhibitors and prevalence of self-reported glaucoma in the United States

Objective

While decreased ocular blood flow is thought to be a possible contributor to glaucoma pathogenesis, it is unclear what role systemic phosphodiesterase inhibitors (PDEi) play. We performed a cross-sectional study of a nationally representative sample of the U.S. population to investigate the relationship between the most commonly used PDEi, sildenafil and theophylline, and self-reported glaucoma.

Methods

We used the National Health and Nutrition Examination Survey 2005–2008 cycles for this observational study. 7,042 participants, aged 40 years and over, responded to a survey item on glaucoma status and were included in the analysis. Multivariable logistic regression models were constructed to evaluate the association between at least 1 year of self-reported PDEi use and prevalent glaucoma. Regressions were adjusted for potential confounding variables, including demographics, socioeconomic status, and general health conditions, and accounted for the complex design of the survey. Sample weights were constructed and used to ensure the generalizability of results.

Results

482 respondents self-reported a diagnosis of glaucoma, of which 11 used sildenafil and 20 used theophylline for at least 1 year. Covariates significantly associated with higher odds of glaucoma prevalence in univariable analyses included older age, black race, former smoking status, diabetes, hyperlipidemia, myocardial infarction, and stroke. Conversely, higher education and income were significantly associated with lower odds of glaucoma prevalence. In regression analyses adjusted for demographic and socioeconomic variables, sildenafil (OR = 4.90, CI: 1.24–19.27, p = 0.025) and theophylline (OR = 3.15, CI: 1.46–6.80, p = 0.005) were significantly associated with higher odds of self-reported glaucoma. These associations held after further adjustment with general health behaviors and conditions for both sildenafil and theophylline.

Conclusions

Use of sildenafil and theophylline for one or more years was associated with greater prevalence of self-reported glaucoma, a finding which requires further prospective study to assess causality and possible mechanisms of action.

Identification of a novel HLA-A*02:01:01 variant, HLA-A*02:01:01:09, in a Taiwanese bone marrow donor

An intronic mutation in intron 3 of A*02:01:01:01 leads to the formation of A*02:01:01:09.

[Predictive value of deubiquitination enzymes USP37 in the prognosis of breast cancer]

OBJECTIVE

To explore the expression of Ubiquitin-specific processing enzyme 37(USP 37)in breast cancer and its association with the prognosis of breast cancer.

METHODS

In this study, the method of Western blot was utilized to examine the expression of USP37 protein in breast cancer fresh tissue. Immunohistochemistry (IHC) was used to determine the expression of USP37 in 533 cases of breast cancer. Receive operating characteristic (ROC) curve analysis was employed to determine a cut-off score for USP37 expression. For validation, the ROC-derived cut-off score was subjected to analysis the association of USP37 expression with cancer patient outcome and clinical characteristics.

RESULTS

USP37 protein was mainly located in cytoplasm of the cell, occasionally in nucleus by immunohistochemistry. In the normal breast tissue, USP37 was not expressed or with low expression level, while in the 533 cases of breast cancer, the high USP37 expression was detected in 50.7% samples (270/533) with corresponding low or negative expression rate 49.3% (263/533). We found that USP37 was highly expressed in primary breast cancer tissues compared to paired adjacent non-cancerous tissues. High expression of USP37 was associated with breast cancer node classification, molecular classification and proliferation biomarker Ki67. Both univariate and multivariate analyses further revealed that USP37 expression was an independent poor prognostic parameter for overall survival (OS), recurrence-free survival (RFS) and metastasis-free survival (MFS) in breast cancer. Furthermore, USP37 expressions divided the luminal and triple negative breast cancer into different prognosis subgroups.

CONCLUSION

Our findings first provide evidences that high expression of USP37 served as an independent molecular biomarker for poor prognosis in breast cancer.

Lifetime medical costs of knee osteoarthritis management in the United States: impact of extending indications for total knee arthroplasty

OBJECTIVE

The impact of increasing utilization of total knee arthroplasty (TKA) on lifetime costs in persons with knee osteoarthritis (OA) is understudied.

METHODS

We used the Osteoarthritis Policy Model to estimate total lifetime costs and TKA utilization under a range of TKA eligibility criteria among US persons with symptomatic knee OA. Current TKA utilization was estimated from the Multicenter Osteoarthritis Study and calibrated to Health Care Cost and Utilization Project data. OA treatment efficacy and toxicity were drawn from published literature. Costs in 2013 dollars were derived from Medicare reimbursement schedules and Red Book Online. Time costs were derived from published literature and the US Bureau of Labor Statistics.

RESULTS

Estimated average discounted (3% per year) lifetime costs for persons diagnosed with knee OA were $140,300. Direct medical costs were $129,600, with $12,400 (10%) attributable to knee OA over 28 years. OA patients spent a mean ± SD of 13 ± 10 years waiting for TKA after failing nonsurgical regimens. Under current TKA eligibility criteria, 54% of knee OA patients underwent TKA over their lifetimes. Estimated OA-related discounted lifetime direct medical costs ranged from $12,400 (54% TKA uptake) when TKA eligibility was limited to Kellgren/Lawrence grades 3 or 4 to $16,000 (70% TKA uptake) when eligibility was expanded to include symptomatic OA with a lesser degree of structural damage.

CONCLUSION

Because of low efficacy of nonsurgical regimens, knee OA treatment-attributable costs are low, representing a small portion of all costs for OA patients. Expanding TKA eligibility increases OA-related costs substantially for the population, underscoring the need for more effective nonoperative therapies.

Patients' willingness to contribute to cost of novel implants in total joint arthroplasty

As health care organizations adapt to more accountable financial models, it is increasingly important to assess how patients value new technologies, and their willingness to contribute to their cost. A questionnaire described features of a 'standard' implant including its longevity and risk of complications. We asked if participants would be willing to contribute to the cost of 3 novel implants with differing longevity and risk of complications. Our cohort included 195 patients, 45% were willing to add a co-pay to increase the longevity. Willingness to pay decreased to 26% with increased risk of complications, and 29% were willing to pay for a decreased risk of complications. Patients with higher education level, private insurance and males were more willing to contribute for a novel prosthesis. This study demonstrated that 26%-45% of patients are willing to share costs of a novel prosthesis. Willingness to pay was associated with the proposed implant benefits and with patient characteristics.

Tanshinone IIA inhibits human prostate cancer cells growth by induction of endoplasmic reticulum stress in vitro and in vivo

BACKGROUND

Tanshinone IIA (Tan-IIA) is one of the major lipophilic components isolated from the root of Salviae Miltiorrhizae Radix. We explored the mechanisms of cell death induced by Tan-IIA treatment in prostate cancer cells in vitro and in vivo.

METHODS

Cells were treated with Tan-IIA and growth inhibition was assessed. Cell cycle profiles after Tan-IIA treatment were determined by flow cytometry. Expression levels of cell cycle regulatory proteins and apoptosis-related proteins were determined after Tan-IIA treatment. Expression levels of endoplasmic reticulum (ER) stress-regulated genes were determined to investigate their role in Tan-IIA-induced cell death. GADD153 expression was knocked down by small interfering RNA (siRNA) transfection. Rate of cell death and proliferation was obtained by 3-(4,5-dimethyl thizol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Antitumor activity of Tan-IIA was performed in LNCaP xenograft model.

RESULTS

Our results showed that Tan-IIA caused prostate cancer cell death in a dose-dependent manner, and cell cycle arrest at G0/G1 phase was noted, in LNCaP cells. The G0/G1 phase arrest correlated with increase levels of CDK inhibitors (p16, p21 and p27) and decrease of the checkpoint proteins. Tan-IIA also induced ER stress in prostate cancer cells: activation and nuclear translocation of GADD153/CCAAT/enhancer-binding protein-homologous protein (CHOP) were identified, and increased expression of the downstream molecules GRP78/BiP, inositol-requiring protein-1α and GADD153/CHOP were evidenced. Blockage of GADD153/CHOP expression by siRNA reduced Tan-IIA-induced cell death in LNCaP cells. Tan-IIA also suppressed LNCaP xenograft tumor growth, causing 86.4% reduction in tumor volume after 13 days of treatment.

CONCLUSIONS

Our findings suggest that Tan-IIA causes G0/G1 cell cycle arrest in LNCaP cells and its cytotoxicity is mediated at least partly by ER stress induction. These data provide evidence supporting Tan-IIA as a potential anticancer agent by inducing ER stress in prostate cancer.

Lifetime risk and age at diagnosis of symptomatic knee osteoarthritis in the US

OBJECTIVE

To estimate the incidence and lifetime risk of diagnosed symptomatic knee osteoarthritis (OA) and the age at diagnosis of knee OA based on self-reports in the US population.

METHODS

We estimated the incidence of diagnosed symptomatic knee OA in the US by combining data on age-, sex-, and obesity-specific prevalence from the 2007-2008 National Health Interview Survey, with disease duration estimates derived from the Osteoarthritis Policy (OAPol) Model, a validated computer simulation model of knee OA. We used the OAPol Model to estimate the mean and median ages at diagnosis and lifetime risk.

RESULTS

The estimated incidence of diagnosed symptomatic knee OA was highest among adults ages 55-64 years, ranging from 0.37% per year for nonobese men to 1.02% per year for obese women. The estimated median age at knee OA diagnosis was 55 years. The estimated lifetime risk was 13.83%, ranging from 9.60% for nonobese men to 23.87% in obese women. Approximately 9.29% of the US population is diagnosed with symptomatic knee OA by age 60 years.

CONCLUSION

The diagnosis of symptomatic knee OA occurs relatively early in life, suggesting that prevention programs should be offered relatively early in the life course. Further research is needed to understand the future burden of health care utilization resulting from earlier diagnosis of knee OA.

Detection of two HLA-A alleles, A*31:30 and A*26:20, in two Taiwanese volunteer bone marrow donors by sequence-based typing

We here report detection of a novel sequence of HLA-A*31:30 and a confirmatory sequence of HLA*26:20 from two Taiwanese individuals. The sequence of A*31:30 is identical to that of A*31:01:02 in exons 2 and 3, except one nucleotide (n.t.) substitution c.539T > G resulting in p.Leu180Trp. The sequence of A*26:20 is identical to A*26:01:01 in exons 2 and 3, except a segment of the sequence from n.t. 78 to n.t.102. The mismatched sequence segment is identical to a sequence segment of A*02:03:01, suggesting that the formation of A*26:20 was resulted from a DNA recombination event between A*26:01:01 and A*02:03:01 sequences. A*26:20 differs from A*26:01:01 with c.98A > T resulting in p.Tyr33Phe.

High-pressure--high-temperature polymorphism in ta: resolving an ongoing experimental controversy

Phase diagrams of refractory metals remain essentially unknown. Moreover, there is an ongoing controversy over the high-pressure melting temperatures of these metals: results of diamond anvil cell (DAC) and shock wave experiments differ by at least a factor of 2. From an extensive ab initio study on tantalum we discovered that the body-centered cubic phase, its physical phase at ambient conditions, transforms to another solid phase, possibly hexagonal omega phase, at high temperature. Hence the sample motion observed in DAC experiments is very likely not due to melting but internal stresses accompanying a solid-solid transformation, and thermal stresses associated with laser heating.

Biochemical and molecular characterization of tyrosine hydroxylase deficiency in Hong Kong Chinese

Tyrosine hydroxylase deficiency is a rare neurotransmitter disorder affecting the rate-limiting step in catecholamine biosynthesis. There are about 40 cases reported worldwide. Here, we report the biochemical and molecular findings of eight unrelated Chinese patients with tyrosine hydroxylase deficiency. We have identified eight novel mutations with 5 missense, 2 nonsense and 1 splicing mutations in the TH gene, namely p.R153X, p.R169X, p.G294R, p.G315S, p.A385V, p.I394T, p.G408R, and c.1163+5G>C. The mutations of the TH gene in Chinese are heterogeneous.

Ordered YBCO sub-micron array structures induced by pulsed femtosecond laser irradiation

We report on the formation of organized sub-micron YBa(2)Cu(3)O(7) (YBCO) dots induced by irradiating femtosecond laser pulses on YBCO films prepared by pulse laser deposition with fluence in the range of 0.21 approximately 0.53 J/cm(2). The morphology of the YBCO film surface depends strongly on the laser fluences irradiated. At lower laser fluence (approximately 0.21 J/cm(2)) the morphology was pattern of periodic ripples with sub-micrometer spacing. Slightly increasing the laser fluence to 0.26 J/cm(2) changes the pattern into organized sub-micron dots with diameters ranging from 100 nm to 800 nm and height of 150 nm. Further increase of the laser fluence to over 0.32 J/cm(2), however, appeared to result in massive melting and led to irregular morphology. The mechanism and the implications of the current findings will be discussed. Arrays of YBCO sub-micron dots with T(c) = 89.7 K were obtained.

Molybdenum at high pressure and temperature: melting from another solid phase

The Gibbs free energies of bcc and fcc Mo are calculated from first principles in the quasiharmonic approximation in the pressure range from 350 to 850 GPa at room temperatures up to 7500 K. It is found that Mo, stable in the bcc phase at low temperatures, has lower free energy in the fcc structure than in the bcc phase at elevated temperatures. Our density-functional-theory-based molecular dynamics simulations demonstrate that fcc melts at higher than bcc temperatures above 1.5 Mbar. Our calculated melting temperatures and bcc-fcc boundary are consistent with the Mo Hugoniot sound speed measurements. We find that melting occurs at temperatures significantly above the bcc-fcc boundary. This suggests an explanation of the recent diamond anvil cell experiments, which find a phase boundary in the vicinity of our extrapolated bcc-fcc boundary.

Identification of differentially expressed genes from the cross-subfamily cloned embryos derived from zebrafish nuclei and rare minnow enucleated eggs

Cross-species nuclear transfer (NT) has been used to retain the genetic viability of a species near extinction. However, unlike intra-species NT, most embryos produced by cross-species NT were unable to develop to later stages due to incompatible nucleo-cytoplasmic interactions between the donor nuclei and the recipient cytoplasm from different species. To study the early nucleo-cytoplasmic interaction in cross-species NT, two laboratory fish species (zebrafish and rare minnow) from different subfamilies were used to generate cross-subfamily NT embryos in the present study. Suppression subtractive hybridization (SSH) was performed to screen out differentially expressed genes from the forward and reverse subtractive cDNA libraries. After dot blot and real-time PCR analysis, 80 of 500 randomly selective sequences were proven to be differentially expressed in the cloned embryos. Among them, 45 sequences shared high homology with 28 zebrafish known genes, and 35 sequences were corresponding to 22 novel expressed sequence tags (ESTs). Based on functional clustering and literature mining analysis, up- and down-regulated genes in the cross-subfamily cloned embryos were mostly relevant to transcription and translation initiation, cell cycle regulation, protein binding, etc. To our knowledge, this is the first report on the determination of genes involved in the early development of cross-species NT embryos of fish.

Immune responses to foot-and-mouth disease virus in pig farms after the 1997 outbreak in Taiwan

This paper reports on a retrospective study of the antibody responses to structural and non-structural proteins of FMD virus O Taiwan 97 in six pig herds in Taiwan in the year after the 1997 Taiwanese FMD outbreak. All herds were vaccinated against FMD after the outbreak as part of the countrywide control program. Three of the herds had confirmed FMD infections (herds N, O and P) and three herds remained non-infected (herds K, L and M). The serum neutralizing antibody titers and the non-structural protein ELISA (NSP) antibody responses in sows and 1-month-old pigs in the infected herds were higher than in the non-infected herds, but over time a number of positive NSP reactors were detected. From the serological studies and the herd monitoring and investigations it was considered that the FMD NSP positive reactors may not have constituted a true reservoir of FMD virus infection especially in herds where susceptible pigs were no longer present post-exposure or post-vaccination. Pigs vaccinated with an unpurified FMD type O vaccines being used at that time also showed false positive responses for NSP antibodies.

Immune responses of pigs to commercialized emulsion FMD vaccines and live virus challenge

The immune response to structural and non-structural proteins (NSPs) was studied on sequential serum samples in swine from O/Taiwan/97 FMDV challenge studies, outbreaks and after vaccination. The results showed that pigs vaccinated with a commercial vaccine prior to or after infection maintained high neutralizing antibody titers with gradual decline from peak titers over the duration of this study. However, neutralizing antibody titers in non-vaccinated pigs only reached moderate levels 2-4 weeks post infection and remained low thereafter. For the 3B and 3ABC NSP antibody ELISA responses, there were gradually decreasing levels of NSP antibody over time. In multiple vaccinations, all pigs showed significant increases in neutralizing antibodies after booster vaccination. For the 3B NSP antibody ELISA after vaccination, the mean S/P ratios for pigs vaccinated with all three FMD vaccines were all below the 0.23 cut-off value set by the manufacture, but some sera from individual vaccinated pigs gave results above this cut-off after primary or secondary vaccination. However, with the 3ABC NSP antibody ELISA, all sera from vaccinated pigs had negative results for NSP antibody for all time points.

Comparison of sensitivity and specificity in three commercial foot-and-mouth disease virus non-structural protein ELISA kits with swine sera in Taiwan

Three commercialized ELISA kits for the detection of antibodies to the non-structural proteins (NSPs) of FMD virus were compared, using sera from uninfected, vaccinated, challenged and naturally infected pigs. The kinetics of the antibody response to NSPs was compared on sequential serum samples in swine from challenge studies and outbreaks. The results showed that ELISA A (UBI) and ELISA B (CEDI) had better sensitivity than that of the 3ABC recombinant protein-based ELISA C (Chekit). The peak for detection of antibodies to NSPs in ELISA C was significantly delayed in sera from natural infection and challenged swine as compared to the ELISA A and B. The sensitivity of the three ELISAs gradually declined during the 6-month post-infection as antibodies to NSP decline. ELISA kits A and B detected NSP antibody in 50% of challenged pigs by the 9-10th-day and 7-8th-day post-challenge, respectively. ELISA B and C had better specificity than ELISA A on sequential serum samples obtained from swine immunized with a type O FMD vaccine commercially available in Taiwan. Antibody to NSPs before vaccination was not detected in swine not exposed to FMD virus, however, antibody to NSPs was found in sera of some pigs after vaccination. All assays had significantly lower specificity when testing sera from repeatedly vaccinated sows and finishers in 1997 that were tested after the 1997 FMD outbreak. However, when testing sera from repeatedly vaccinated sows or finishers in 2003-2004, the specificity for ELISAs A, B and C were significantly better than those in 1997. This effect was less marked for ELISA A. The ELISA B was the best test in terms of the highest sensitivity and specificity and the lowest reactivity with residual NSP in vaccinates.

Adsorption and oxidation of ethanol on colloid-based Pt/C, PtRu/C and Pt3Sn/C catalysts: In situ FTIR spectroscopy and on-line DEMS studies

The interaction of colloid-based, carbon supported Pt/C (40 wt%), PtRu/C (45 wt%) and Pt3Sn/C (24 wt%) catalysts with ethanol and their performance for ethanol electrooxidation were investigated in model studies by electrochemical, in situ infrared spectroscopy and on-line differential electrochemical mass spectrometry measurements. The combined application of in situ spectroscopic techniques on realistic catalysts and under realistic reaction (DEMS, IR) and transport conditions (DEMS) yields new insight on mechanistic details of the reaction on these catalysts under the above reaction and transport conditions. Based on these results, the addition of Sn or Ru, though beneficial for the overall activity for ethanol oxidation, does not enhance the activity for C-C bond breaking. Dissociative adsorption of ethanol to form CO2 is more facile on the Pt/C catalyst than on PtRu/C and Pt3Sn/C catalysts within the potential range of technical interests (<0.6 V), but Pt/C is rapidly blocked by an inhibiting CO adlayer. In all cases acetaldehyde and acetic acid are dominant products, CO2 formation contributes less than 2% to the total current. The higher ethanol oxidation current density on the Pt3Sn/C catalyst at these potentials results from higher yields of C2 products, not from an improved complete ethanol oxidation to CO2.

Mycoplasma hyorhinis in Taiwan: Diagnosis and isolation of swine pneumonia pathogen

This study attempted to determine whether one multiplex polymerase chain reaction (PCR) is an effective adjunct method for diagnosing Mycoplasma hyopneumoniae and Mycoplasma hyorhinis infection, and whether M. hyorhinis should be considered as an enzootic pneumonia or porcine respiratory disease complex pathogen in Taiwan. To our knowledge, this study is the first to isolate and identify M. hyorhinis as a porcine pathogen in Taiwan. A novel isolation method and a multiplex PCR test were applied to detect and isolate M. hyorhinis. The correlation of M. hyorhinis with swine pneumonia was also examined using a challenge test. Based on weight, 18 pigs were assigned to three groups and housed throughout the study in a specific-pathogen-free (SPF) facility and provided with aseptic feed and water. Groups 1 (n=6) and 2 (n=6) were challenged with 5mL M. hyorhinis culture via tracheal intubation on day 1. The M. hyorhinis strains ATIT-1, -3, and-7 were used to infect group 1 and the strain ATCC 27717 was used for group 2. Culture medium was replaced by phosphate-buffered saline in group 3 (n=6). All pigs were slaughtered on day 28, and their lungs were removed for examination of lesions. Of the six pigs in group 1 challenged with wild-type strains, two had typical mycoplasma pneumonia lesions. No gross lung lesions were observed in groups 2 and 3. Although further examination is necessary to confirm that wild-type strains can cause pneumonia, it appears that M. hyopneumoniae is no longer the only mycoplasma pathogen implicated in the diagnosis of swine enzootic pneumonia (SEP).

Group i metabotropic glutamate receptors in spiral ganglion neurons contribute to excitatory neurotransmissions in the cochlea

Evidence has accumulated over the years supporting glutamate as the primary neurotransmitter used by hair cells in afferent cochlear neurotransmission. Besides acting on ionotropic glutamate receptors, glutamate also activates second messenger systems via G-protein-coupled metabotropic glutamate receptors (mGluRs) to modulate neuronal excitability. However, it is unclear whether mGluRs participate in cochlear neurotransmission. We present evidence directly supporting a functional role for group I metabotropic glutamate receptors (mGluRIs) in spiral ganglion (SG) neurons. The presence of mGluRI and downstream G-protein subunits was demonstrated by molecular biology and immunolabeling methods. Direct activation of mGluRIs in cultured SG neurons resulted in transient increases of intracellular Ca(++) concentration and transient inward currents that gave rise to firings of multiple action potentials. These responses showed mGluRI pharmacological specificity and quickly desensitized. We next examined changes in cochlear function after noise exposure as a result of pharmacologically manipulating cochlear glutamate neurotransmission. These in vivo tests showed that blocking non-N-methyl-D-aspartic acid glutamate receptors was sufficient to eliminate compound action potentials of the auditory nerve, and pharmacologically inhibiting mGluRIs in the cochlea did not significantly affect the hearing threshold. In contrast, blocking mGluRIs lowered the amplitude of compound action potentials at louder sound levels and reduced the noise-induced temporary threshold shift. Our results suggest that although mGluRIs did not initiate fast excitatory cochlear neurotransmission, their activation contributed to the growth of excitatory responses of the cochlea. As a result, the cochlea was more resistant to noise-induced temporary hearing losses without the activation of mGluRIs in SG neurons.

Childhood nephrotic syndrome in relapse is associated with down-regulation of monocyte CD14 expression and lipopolysaccharide-induced tumour necrosis factor-alpha production

Interleukin-13 (IL-13) is a known modulator of monocyte function, down-regulating monocyte surface markers such as CD14 and proinflammatory cytokines. We have shown previously that lymphocyte IL-13 gene expression was up-regulated during relapses in children with steroid-responsive nephrotic syndrome (SRNS). In this study, we examined the monocyte mRNA expression and lipopolysaccharide (LPS)-stimulated intracellular production of tumour necrosis factor-alpha (TNF-alpha) and IL-8 in children with SRNS during relapse and remission. Additionally, we investigated CD14 mRNA levels, CD14 surface expression and its soluble component (sCD14) in serum. Our results showed that the percentages of TNF-alpha positive monocytes following LPS stimulation were significantly lower in nephrotic children in relapse (64.4 +/- 13.7%) compared to remission (81.6 +/- 9.0%, P < 0.005). This was associated with down-regulation of CD14 mRNA, as well as both membrane and sCD14 in patients with nephrotic relapse (82.9 +/- 10.1% and 1.23 +/- 0.30 micro g/ml, respectively) compared to remission (93.9 +/- 3.2% and 1.77 +/- 0.82 micro g/ml, respectively) (P < 0.003). Although we demonstrated a decrease in LPS-stimulated intracellular production of TNF-alpha in monocytes from patients with nephrotic relapse, we were unable to show a concomitant decrease in mRNA expression during relapses. This could be explained by down-regulation of gene expression at the translational rather than transcriptional level. In conclusion, it is conceivable that up-regulation of T-cell IL-13 production in children with active nephrotic relapse was associated with suppression of monocyte CD14 expression, down-regulating pro-inflammatory cytokine production, and could account for the increased susceptibility to bacterial sepsis seen in nephrotic children in active relapse.

Validation of a multiplex RT-PCR assay for screening significant oncogene fusion transcripts in children with acute lymphoblastic leukaemia

In childhood acute lymphoblastic leukaemia (ALL), cytogenetics play an important role in diagnosis, allocation of treatment and prognosis. Conventional cytogenetic analysis, involving mainly karyotyping in our experience, has not been successful in a large proportion of cases due to inadequate metaphase spreads and poor chromosome morphology. Our aim is to develop a highly sensitive and specific method to screen simultaneously for the four most frequent fusion transcripts resulting from specific chromosomal translocations, namely, both the CML- and ALLtype BCR-ABL transcripts of t(9;22), E2A-PBX1 transcript of t(1;19), the MLL-AF4 transcript of t(4;11) and TEL-AML1 (also termed ETV6-CBFA2) of the cryptic t(12;21). A multiplex reverse transcription polymerase chain reaction protocol (RT-PCR) was developed and tested out on archival bone marrow samples and leukaemia cell lines. In all samples with a known translocation detected by cytogenetic techniques, the same translocation was identified by the multiplex-PCR assay. Multiplex RT-PCR assay is an effective, sensitive, accurate and cost-effective diagnostic tool which can improve our ability to accurately and rapidly risk-stratify patients with childhood ALL.

Optimization of foot-and-mouth disease vaccination protocols by surveillance of neutralization antibodies

An appropriate immunization program for pigs in a foot-and-mouth disease (FMD) endemic area was proposed based on data analysis obtained from serological surveillance in Taiwan, after an intensive vaccination program. To provide an adequate passive immunity for piglets, gilts that have completed two basic vaccinations must be boosted once before breeding. To achieve an efficient response to the FMD vaccine for piglets born to well vaccinated sows, vaccination need to be delayed until 10-12 weeks of ages for the first immunization, followed by a boost 4 weeks later.

Junceol A, a new sesquiterpenoid from the sea pen Virgularia juncea

A new sesquiterpenoid, junceol A(1), as well as two known diterpenoids, sclerophytin A (2) and cladiellisin (3), have been isolated from the sea pen octocoral Virgularia juncea. The structure of metabolite 1 was determined by extensive spectral analysis. Compounds 1-3 have been shown to exhibit cytotoxicity toward P-388 cancer cells.

Synthetic peptide-based vaccine and diagnostic system for effective control of FMD

We have designed synthetic peptides corresponding to two different regions of the genome of foot-and-mouth disease virus (FMDV) that are effective as (a) a vaccine or (b) a diagnostic reagent which differentiates convalescent from vaccinated animals, respectively. The peptide vaccine is based on a sequence from the prominent G-H loop of VP1, one of the four capsid proteins. The sequence was optimized by the inclusion of a cyclic constraint and adjoining sequences, and broader immunogenicity was obtained by the incorporation of consensus residues at hypervariable positions. The peptide also included a promiscuous T-helper epitope for effective immunogenicity in outbred populations of large animals.The diagnostic reagent, a peptide based on non-structural (NS) protein 3B, is used in immuno-assays for the detection of antibodies. Antibodies to this NS protein are present in the sera of infected animals but not in the sera of vaccinated animals. The VP1 peptide can be used in complementary immuno-assays for confirmation of NS test results and to monitor for vaccination. This system for differential diagnosis is important to establish the disease-free status of a country.

New DR5 sequences: a novel DRB1*11122 allele identified in Paiwan tribe members of Taiwan and a corrected sequence for the DRB1*1201 allele

We report herein the identification of a new DRB1 allele using sequence-based typing (SBT). This novel allele, HLA-DRB1*11122, was found in an aboriginal individual (SWP71) from the Paiwan tribe in the southern part of Taiwan. This individual was typed by SBT method as having an HLA genotype of HLA-A*24021/24021, HLA-B*4001/4002, HLA-DRB1*11122/15011, HLA-DRB3*0202, and HLA-DRB5*01011. This new allele differs from DRB1*1112 in the polymorphic exon 2 only at codon 34 (CAA-->CAG; both specify glutamine) and from DRB1*1110 in the exon 2 sequence only at codon 32 (CAT-->TAT; H32T). The most likely candidate allele which is found in the aboriginal populations of Taiwan and which may mutate into this new allele is DRB1*11011. DRB1*11122 allele differs from DRB1*11011 allele in the polymorphic exon 2 at both codon 34 (CAA-->CAG) and codon 37 (TAC-->TTC; T37F). This novel HLA-DRB1*11122 allele was also found in another aboriginal individual (SWP90) from the same Paiwan tribe. This SWP90 individual was typed by SBT method as having an HLA genotype of HLA-A*24021/24021, HLA-B*4002/5502, HLA-DRB1*11122/1201, and HLA-DRB3*01011/0202. However, the original DRB1*1201 sequence from HERLUFF was found to be erroneously reported and the corrected sequence from SWP90 is now presented herein.

[Studies on the triterpene sapogenins from Albizziae Cortex]

A new sapogenin named Julibrogenin A was isolated from the stem bark of Albizzia julibrissin Durazz (Albizziae Cortex). Based on chemical and spectral studies, their structure has been identified as 21-O-(2-hydroxymethyl-6-methyl-6-methoxyl-2,7-octadienoyl)-acacic acid. In addition, machaerinic acid lactone, machaerinic acid methylester, acacigenin B and julibrotriterpenoidal lactone A were also isolated from this plant and characterised.

[Structure determination of three saponins from the stem bark of Albizzia julibrissin Durazz]

Three new saponins named Julibroside J1, J2 and J3 were isolated from the stem bark of Albizzia julibrissin Durazz (Albizziae Cortex). Based on chemical and spectral methods, e.g. 1H- and 13C-NMR, DEPT, COSY CH-COSY, TOCSY, HMQC-COSY, HMQC-TOCSY, NOESY, HMBC, their structures have been identified as; Julibroside J1 (one triterpene, nine sugars, two monoterpenes I); Julibroside J2(one triterpene, eight sugars two monoterpenes II); Julibroside J3(one triterpene, nine sugars two monoterpenes III).

Polymorphism of human HLA-DRB1 antigens generated by genetic exchange between DR2 (DRB1*15011) and DR6 (DRB1*1405) alleles: a novel DRB1 allele (DRB1*1437) identified in a Paiwan tribe member of Taiwan

We report herein the identification of a new DRB1 allele using sequence-based typing (SBT). This novel allele, HLA-DRB1*1437, was found in an aboriginal individual from the Paiwan tribe in the southern part of Taiwan. This individual was typed by SBT method as having an HLA genotype of HLA-A*02011/0203, HLA-B*15011/3901, HLA-DRB1*11011/1437, HLA-DRB3*0202/0202, and HLA-DPB1*0501/1301. This new allele differs from DRB1*1309 in the 5'-end nucleotide sequence of polymorphic exon 2 at codon 16 (CAT-->CAA; H16Q), codon 37 (AAC-->TTC; R37F), codon 47 (TTC-->TAC; F47Y), and codon 58 (GCC-->GCT; both specify alanine). By sequence comparison, it was found that this new allele has a 5'-end sequence (from amino acid residues 7 to 66) identical to that found in the DRB1*1405 allele and a 3'-end sequence (from amino acid residues 58 to 94) identical to that found in the DRB1*15011 allele. Both DRB1*1405 and DRB1*15011 alleles have been identified among the Paiwan members (Note).

[Expression of bcl-2, c-myc genes and their relationship in patients with acute leukemia]

OBJECTIVE

This paper was to explore the expressions of bcl-2, c-myc genes and the relationship between them in bone marrow from patients with acute leukemia (AL).

METHODS

In situ hybridization was used to detect bcl-2 and c-myc mRNA. Immune cytochemistry was used to detect bcl-2 and c-myc protein.

RESULTS

The expressions of bcl-2, c-myc mRNA and proteins were significantly increased in AL; There were not significant differences in bcl-2 mRNA and protein, c-myc mRNA and protein between the patients with acute lymphocytic leukemia and acute nonlymphocytic leukemia; There were linear correlations between bcl-2 mRNA and bcl-2 protein, between c-myc mRNA and c-myc protein, between bcl-2 mRNA and c-myc mRNA, between bcl-2 protein and c-myc protein.

CONCLUSION

bcl-2 and c-myc genes play an important role in pathogenesis and the development of AL.

Intelligence and event-related potentials for young female human volunteer apolipoprotein E epsilon4 and non-epsilon4 carriers

The apolipoprotein E (APOE) epsilon4 allele is associated with late-onset Alzheimer's disease and cognitive function in aging normal populations. To study the effect of the presence of the epsilon4 allele on cognitive function, we compared intelligence-test scores and component values for event-related potentials for epsilon4 and non-epsilon4 carriers in a group of 134 young females. The results demonstrate modest increases in performance intelligence quotient (IQ) and N100 amplitude for epsilon4 carriers (P=0.038 and 0.068, respectively). Our findings suggest that cognitive impairment, associated with the presence of the epsilon4 allele, is age-dependent and thus not probable for young women. The higher performance IQ scores demonstrated for epsilon4 carriers require further exploration.

Self-diffusion of small clusters on fcc metal (111) surfaces

We use ab initio density-functional theory supplemented with the embedded-atom method to study the self-diffusion of small clusters on the (111) surface of eight fcc metals. A zigzag motion is found to be important in the dimer and tetramer diffusions. The dimer diffuses by a zigzag and concerted motion. The trimer diffuses by a concerted three-atom motion. The tetramer diffuses through a zigzag motion where only two atoms move simultaneously in each step. Thus, instead of increasing, the migration energy is lowered (or stays constant) for the tetramer as compared to that for the trimer. This novel break of the upwards trend in migration energy is predicted to be a general phenomenon.

Competency in community-oriented health care. Instrument development

To competently deal with changes in the health care system, health professionals for the future must have expanded abilities and new attitudes. Education of health professionals for community-oriented health care (COHC) is being promoted as one approach to achieve this focus. This article reports on the development and testing of the Community-Oriented Health Care Competency Scale, which measures knowledge, attitudes, and intention to practice COHC. Results of testing demonstrate adequate reliability for a new instrument: an alpha coefficient of .95 for the Knowledge subscale, .68 for the Attitude subscale, and .93 for the Intention to Practice subscale. Content Validity of the instrument is based on the literature review, focus group sessions, and expert opinion. The instrument may be used to assess competency of health professions students in COHC, but continued testing is needed.

Application of modified CHIP-AE in a vocational high school

Adolescent health behaviors tend to cluster and vary by such factors as grade, age, and racial/ethnic background. A population-based instrument was needed to assess health behaviors of the students in a vocational high school in the City of Chicago. To reduce respondent burden, Child Health and Illness Profile--Adolescent Edition (CHIP-AE) was modified by omitting seven subdomains. Ninety-three boys and 245 girls voluntarily participated in the study. Pearson correlation coefficients, MANOVA, and ANOVA were used in data analysis. Modified CHIP-AE was found to have acceptable reliability and detect the expected differences of adolescent health behaviors by gender and age. Modified CHIP-AE can be used to assess adolescent health behaviors in an urban vocational high school. It can also be used to target the subgroups of students with specific needs for health services.

Perspectives of women whose sons become adolescent fathers

PURPOSE

The purpose of this study was to describe adolescent fatherhood from the perspectives of these young men's mothers.

DESIGN

A descriptive qualitative design was chosen because of the exploratory nature of this study.

METHODS

Data collection and analysis were guided by naturalistic inquiry that permits theory to emerge from the data. The data were collected during a 1-hour focus group interview performed at a public high school located proximal to a large public housing project in a large Midwestern city. Five mothers of adolescent fathers were recruited from a variety of sources using a modified snowball approach.

RESULTS

The seven major themes that emerged from the data were: barriers to fatherhood, value of fatherhood, transition to fatherhood, competencies of fatherhood, role-set relationships, social norms of fatherhood, and father-child contact. These women indicated that they felt their sons' youth influenced every aspect of the fatherhood experiences.

CLINICAL IMPLICATIONS

Nurses who work with adolescent parents are ideally situated to encourage the support of adolescent fathers and their families. Future research should identify methods useful for supporting or discouraging paternal involvement of adolescent fathers, and effective intervention strategies for adolescent fathers and their families.

Characterization and quantitation of extracellular collagen matrix in myocardium of pigs with spontaneously occurring hypertrophic cardiomyopathy

The extracellular matrix between cardiocytes has been suggested to play an important role in maintaining the structure and function of the heart. The purpose of this study was to elucidate the morphological changes in the collagen of the extracellular matrix (ECM) in the hearts of pigs with hypertrophic cardiomyopathy. Sixty pigs diagnosed with hypertrophic cardiomyopathy from 605 purebred Landrace pigs ages 6 to 9 months were used in this study. Morphologically, these pigs with hypertrophic cardiomyopathy had increased heart weight and heart-to-body weight ratio, thickening of the left ventricular (LV) and right ventricular (RV) free walls and septum, disorientation of cardiocytes, myocardial fibrosis, and intramural coronary arteriosclerosis. Similar observations have been described in our preliminary report (Cardiovasc Pathol 3:261, 1994). In the present study, we have modified the silver impregnation technique to stain paraffin-embedded sections to demonstrate three types of ECM. There were endomysial struts, perimysial weaves, and epimysial coils in the myocardium. The light microscopic findings of the struts, weaves, and coils were also confirmed by scanning electromicroscopic examination. The numbers of these fine structures were increased significantly in the pigs with hypertrophic cardiomyopathy. In addition, the amounts of collagen in the LVs, RVs, and septum (Sep) in pigs with hypertrophic cardiomyopathy (LV = 19.37+/-0.79, RV = 23.72+/-0.72, Sep = 20.38+/-0.94 microg/mg, n = 60) were significantly higher (p < 0.01) than that in similar areas of normal pigs (LV = 14.56+/-1.11, RV = 18.90+/-1.02, Sep = 14.99+/-1.33 microg/mg, n = 30, respectively). Our findings of an overall increase of collagen content suggested that the accumulation of collagen matrix might be another factor responsible for the diastolic dysfunction of hypertrophic cardiomyopathy. These results might also infer that the increased collagen matrix could contribute to the stiffness of the cardiac chambers, thereby markedly affecting systolic and diastolic function of the heart. These observations provide further support that the pig may be an animal model for human cardiovascular disease.