Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Arch Gerontol Geriatr ; 125: 105483, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38788370

ABSTRACT

Memory plays a crucial role in cognitive health. Social isolation (SI) and loneliness (LON) are recognized risk factors for global cognition, although their combined effects on memory have been understudied in the literature. This study used three waves of data over six years from the Canadian Longitudinal Study on Aging to examine whether SI and LON are individually and jointly associated with memory in community-dwelling middle-aged and older adults (n = 14,208). LON was assessed with the question: "In the last week, how often did you feel lonely?". SI was measured using an index based on marital/cohabiting status, retirement status, social activity participation, and social network contacts. Memory was evaluated with combined z-scores from two administrations of the Rey Auditory Verbal Learning Test (immediate-recall, delayed-recall). We conducted our analyses using all available data across the three timepoints and retained participants with missing covariate data. Linear mixed models were used to regress combined memory scores onto SI and LON, adjusting for sociodemographic, health, functional ability, and lifestyle variables. Experiencing both SI and LON had the greatest inverse effect on memory (least-squares mean: -0.80 [95 % confidence-interval: -1.22, -0.39]), followed by LON alone (-0.73 [-1.13, -0.34]), then SI alone (-0.69 [-1.09, -0.29]), and lastly by being neither lonely nor isolated (-0.65 [-1.05, -0.25]). Sensitivity analyses confirmed this hierarchy of effects. Policies developed to enhance memory in middle-aged and older adults might achieve greater benefits when targeting the alleviation of both SI and LON rather than one or the other individually.

2.
BMC Health Serv Res ; 23(1): 1427, 2023 Dec 16.
Article in English | MEDLINE | ID: mdl-38104086

ABSTRACT

BACKGROUND: The role of visiting health services has been proven to be effective in promoting the health of older populations. Hence, developing a web system for nurses may help improve the quality of visiting health services for community-dwelling frail older adults. This study was conducted to develop a web application that reflects the needs of visiting nurses. METHODS: Visiting nurses of public health centers and community centers in South Korea participated in the design and evaluation process. Six nurses took part in the focus group interviews, and 21 visiting nurses and community center managers participated in the satisfaction evaluation. Focus group interviews were conducted to identify the needs of visiting nurses with respect to system function. Based on the findings, a web application that can support the effective delivery of home visiting services in the community was developed. An artificial intelligence (AI) algorithm was also developed to recommend health and welfare services according to each patient's health status. After development, a structured survey was conducted to evaluate user satisfaction with system features using Kano's model. RESULTS: The new system can be used with mobile devices to increase the mobility of visiting nurses. The system includes 13 features that support the management of patient data and enhance the efficiency of visiting services (e.g., map, navigation, scheduler, protocol archives, professional advice, and online case conferencing). The user satisfaction survey revealed that nurses showed high satisfaction with the system. Among all features, the nurses were most satisfied with the care plan, which included AI-based recommendations for community referral. CONCLUSIONS: The system developed from the study has attractive features for visiting nurses and supports their essential tasks. The system can help with effective case management for older adults requiring in-home care and reduce nurses' workload. It can also improve communication and networking between healthcare and long-term care institutions.


Subject(s)
Artificial Intelligence , Nurses, Community Health , Humans , Aged , Nigeria , Delivery of Health Care , Internet
3.
Animals (Basel) ; 13(9)2023 Apr 23.
Article in English | MEDLINE | ID: mdl-37174480

ABSTRACT

The brood reduction hypothesis, which explains asynchronous hatching in birds, as an adaptation that enables selective survival of older nestlings when availability of food is unpredictable. This study was conducted in order to determine whether the brood reduction hypothesis can explain asynchronous hatching in passerines. Infrared cameras were installed inside nest boxes where great tits (Parus major) were attempting to reproduce in order to determine whether the parents practiced selective feeding of older nestlings. According to the results of the study, no significant difference was observed between the hatching order and the average number of feedings per nestling. In addition, when examining the distribution of food according to hatching order over time, every 30 min, beginning at 9 a.m., selective distribution of food to older nestlings was not observed. In conclusion, use of the brood reduction hypothesis, which supports selective provision of beneficial feeding of older and larger nestlings, to explain the asynchronous hatching of passerines is problematic, thus conduct of future studies focusing on other hypotheses in order to explain the asynchronous hatching of this passerine bird will be necessary.

4.
OTJR (Thorofare N J) ; 43(1): 98-108, 2023 01.
Article in English | MEDLINE | ID: mdl-35189757

ABSTRACT

Age-related vision loss (ARVL) has been shown to interfere with older adults' occupational engagement. The primary purpose was to examine the role social networks play in facilitating/constraining engagement in desired occupations for older adults with ARVL. This study adopted a constructivist narrative methodology. Five older adults, ≥ 60 years of age with ARVL, participated in three virtual interviews, which were coded using thematic analysis. Three overarching themes were identified: (a) Diverse Social Networks Fulfill Different Occupational and Psychosocial Needs, (b) Retaining a Sense of Independence through Seeking Reciprocity in Social Relationships, and (c) Community Mobility and Technology Support as Essential for Preserving Social Relationships. Findings broaden understandings of how informal/formal social networks are involved in shaping visually-impaired older adults' adaptation to ARVL and related occupational changes. Findings may help improve the quality and delivery of low-vision rehabilitation services to optimize their contribution to occupational engagement.


Subject(s)
Social Networking , Vision Disorders , Humans , Aged , Vision Disorders/psychology , Vision Disorders/rehabilitation , Interpersonal Relations , Narration
5.
Arch Gerontol Geriatr ; 104: 104801, 2023 01.
Article in English | MEDLINE | ID: mdl-36081231

ABSTRACT

BACKGROUND: Some research suggests social isolation and loneliness are important risk factors for reduced successful aging and cognitive health. However, findings are inconsistent and no prior systematic review has investigated whether social isolation and loneliness are associated with the memory domain of cognition. This review examined whether social isolation and loneliness individually and jointly affected the memory of middle- and older-aged adults. METHODS: We used PubMed, PsycInfo, and Scopus to search for comparative studies that examined the impact of both loneliness and social isolation (e.g., social activity, social networks) on memory (including all subtypes) in populations aged ≥ 45 years. Three raters performed data extraction and risk of bias assessment using the Joanna Briggs Institute checklist. Data were synthesized narratively following the Synthesis without Meta-Analysis guideline. RESULTS: In 12 included articles, higher levels of loneliness and social isolation (combining a range of different indicators) were associated with lower memory performance, where the interaction between loneliness and social isolation had the largest adverse effect on memory, followed by social isolation alone, and followed by loneliness alone. However, substantial heterogeneity was observed in the composition of the two most common indicators of social isolation (social network size, social activity participation), with the magnitude of most results being clinically non-important. Most articles had moderate risk of bias. CONCLUSION: This review found an inverse association between social isolation/loneliness and memory, and outlines future steps to systematically combine the two constructs and measure social isolation in a consistent, multi-modal format.


Subject(s)
Loneliness , Social Isolation , Humans , Adult , Middle Aged , Loneliness/psychology , Social Isolation/psychology , Risk Factors , Aging , Cognition
6.
Korean J Fam Med ; 43(4): 225-230, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35903045

ABSTRACT

BACKGROUND: Since the era of "thyroid cancer epidemic," many Korean academic societies discouraged the use of ultrasonography in healthy individuals and revised the Korean Thyroid Imaging Reporting and Data System to address the overscreening and overdiagnosis issues. This study aimed to evaluate the change in the diagnostic effectiveness of thyroid cancer screening over the last decade. METHODS: This single-center, retrospective observational study analyzed the data of 125,962 thyroid nodules obtained during cancer screening at the health promotion center of Seoul National University Bundang Hospital from 2010 to 2019. Only 327 thyroid cancer cases pathologically confirmed by fine-needle aspiration (FNA) were included in the study. The strength of the association between the number of FNA and (1) the number of thyroid cancer diagnoses, (2) the positive predictive values (PPVs), and (3) the difference in PPV from the previous year were evaluated using Pearson's correlation analysis. RESULTS: The number of thyroid FNA biopsies as well as the thyroid cancer diagnoses decreased from 2010 to 2019 (166 to 48 [-71.1%] vs. 43 to 22 [-48.8%]). The PPV of FNA biopsies increased from 25.9% to 45.8% (+76.8%) and was negatively correlated with the number of FNA biopsies performed (R=-0.87, P<0.001). The difference in PPV from the previous year increased similarly but without statistical significance (R=-0.59, P=0.09). CONCLUSION: The diagnostic efficiency of thyroid cancer screening has increased over the last decade, as evidenced by the increasing PPV of FNA biopsies.

7.
Anal Bioanal Chem ; 414(10): 3257-3265, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35029693

ABSTRACT

During the recent several decades, lateral flow immunoassay (LFIA) constructed with gold nanoparticle (AuNP) has been widely utilized to conveniently detect target analyte. However, AuNP-based LFIA has limitations, such as limited detection sensitivity and quantification capability. Herein, to overcome these constraints, we have developed cerium oxide nanoparticle (nanoceria)-based LFIA for C-reactive protein (CRP) detection in human serum samples. It was fabricated with nanoceria, a notable nanozyme that shows an oxidase activity to quickly oxidize organic substrate, such as 3,3',5,5'-tetramethylbenzidine (TMB), to produce colored product without any oxidizing agent (e.g., hydrogen peroxide), which is advantageous for realizing point-of-care testing (POCT) applications. By employing human blood serum spiked with CRP, the nanoceria-based LFIA showed two blue-colored lines on the test and control region within 3 min via TMB oxidation, by the captured nanoceria through antigen-antibody interaction. The produced blue-colored lines were distinguished by naked eyes and quantitated with real images acquired by a conventional smartphone with the ImageJ software. With this strategy, target CRP was specifically determined down to 117 ng mL-1 with high detection precisions yielding coefficient of variation of 9.8-11.3% and recovery of 90.7-103.2% using human blood serum samples. This investigation demonstrates the potential of oxidase-like nanoceria for developing LFIA, which is particularly useful in instrumentation-free POCT environments.


Subject(s)
Colorimetry , Metal Nanoparticles , C-Reactive Protein , Cerium , Gold , Humans , Hydrogen Peroxide , Immunoassay
8.
Knee Surg Sports Traumatol Arthrosc ; 30(2): 456-463, 2022 Feb.
Article in English | MEDLINE | ID: mdl-32681285

ABSTRACT

PURPOSE: There has been a general consensus regarding the varus phenotype of the proximal tibia in osteoarthritic patients with varus knee alignment of the whole limb. However, a valgus phenotype of the distal femur may occur in osteoarthritic patients with varus knee alignment. This study evaluated the distal femur phenotype in varus osteoarthritic knees. METHODS: This study included 128 patients who underwent primary total knee arthroplasty (TKA) by computer-assisted navigation for primary medial osteoarthrosis with varus knee alignment. The hip-knee-ankle (HKA) angle, medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and joint line convergence angle (JLCA) were measured on which radiographs preoperatively. The radiographic parameters were compared between groups with HKA angle varus ≥ 10° and < 10°. RESULTS: The MPTA was significantly lower (4°) in the HKA angle varus ≥ 10° group than in the < 10° group (82.13° vs. 86.13° P = 0.001), but the LDFA did not differ significantly between the groups (89.81° vs. 89.19° P = 0.181). Regarding the JLCA, the varus ≥ 10° group showed a 1.3° greater lateral widening than the varus < 10° group (4.87 vs. 3.56, P = 0.002). The MPTA was the only independent predictor of the MA of the lower limb (ß = -  0.353, P < 0.001). CONCLUSION: One-third of varus osteoarthritic knees had a distal femur valgus phenotype. Varus knee alignment was mainly affected by proximal tibia varus rather than by distal femur varus. LEVEL OF EVIDENCE: Level III, consecutive case series.


Subject(s)
Femur , Osteoarthritis, Knee , Femur/diagnostic imaging , Femur/surgery , Humans , Knee Joint/diagnostic imaging , Knee Joint/surgery , Lower Extremity , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/surgery , Phenotype , Retrospective Studies , Tibia/diagnostic imaging , Tibia/surgery
9.
Appl Opt ; 60(24): 7391-7399, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34613028

ABSTRACT

We propose a new learning and inferring model that generates digital holograms using deep neural networks (DNNs). This DNN uses a generative adversarial network, trained to infer a complex two-dimensional fringe pattern from a single object point. The intensity and fringe patterns inferred for each object point were multiplied, and all the fringe patterns were accumulated to generate a perfect hologram. This method can achieve generality by recording holograms for two spaces (16 Space and 32 Space). The reconstruction results of both spaces proved to be almost the same as numerical computer-generated holograms by showing the performance at 44.56 and 35.11 dB, respectively. Through displaying the generated hologram in the optical equipment, we proved that the holograms generated by the proposed DNN can be optically reconstructed.

10.
Sensors (Basel) ; 21(15)2021 Jul 22.
Article in English | MEDLINE | ID: mdl-34372214

ABSTRACT

This paper proposes a method to embed and extract a watermark on a digital hologram using a deep neural network. The entire algorithm for watermarking digital holograms consists of three sub-networks. For the robustness of watermarking, an attack simulation is inserted inside the deep neural network. By including attack simulation and holographic reconstruction in the network, the deep neural network for watermarking can simultaneously train invisibility and robustness. We propose a network training method using hologram and reconstruction. After training the proposed network, we analyze the robustness of each attack and perform re-training according to this result to propose a method to improve the robustness. We quantitatively evaluate the results of robustness against various attacks and show the reliability of the proposed technique.


Subject(s)
Computer Security , Image Interpretation, Computer-Assisted , Algorithms , Neural Networks, Computer , Reproducibility of Results
11.
Opt Express ; 28(24): 36327-36345, 2020 Nov 23.
Article in English | MEDLINE | ID: mdl-33379729

ABSTRACT

In this paper, we propose a new method for coding a full complex hologram with random phase. Since holograms with random phase have very unique spatial and frequency characteristics, a new compression method suitable for such holograms is required. We analyze the frequency characteristics of holograms with random phases and propose a new adaptive discrete wavelet transform (aDWT). Next, we propose a new modified zerotree alogrithm (mZTA) suitable for the subband configuration generated by the modified wavelet transform method. The results of the compression using the proposed method showed higher efficiency than the previous method, and the reconstructed images showed visually superior results.

12.
Article in English | MEDLINE | ID: mdl-32075213

ABSTRACT

This study set out to investigate the effects of multiple roles on depressive symptoms in women. The role of women was divided into worker, household worker, spouse, parent, and caregiver roles to identify the differences in depressive symptoms according to the number of roles, role-fulfillment, and role-combination. Using the sixth raw data of the 2016 Korean Longitudinal Survey of Women and Families for analysis, the data had 6198 respondents who did not have missing values in the major variables. There are three main findings of this study: (1) as the number of roles increased, depressive symptoms of women was decreased. In addition, role-combination was a more meaningful element; (2) women who did not have any roles tended to be more depressed; (3) the caregiver role showed a negative effect on depressive symptoms of women. This study was to include the various aspects of women's roles and to determine the effects of multi-roles on depressive symptoms in women.


Subject(s)
Depression/epidemiology , Gender Identity , Adult , Caregivers , Family Characteristics , Female , Humans , Middle Aged , Mothers , Republic of Korea/epidemiology , Spouses , Young Adult
13.
Clin Breast Cancer ; 18(5): e1087-e1091, 2018 10.
Article in English | MEDLINE | ID: mdl-29703689

ABSTRACT

BACKGROUND: Neoadjuvant systemic therapy (NST) is performed to increase the rate of breast-conserving surgery in advanced breast cancer patients. Although magnetic resonance imaging (MRI) is accurate in predicting residual cancer, if calcification remains, the issue of whether to perform the surgery on the basis of the residual tumor prediction range in mammography (MMG) or MRI has not yet been elucidated. This study aimed to estimate the accuracy of predicting residual tumor after NST for residual microcalcification on mammographic and enhancing lesion on MRI. PATIENTS AND METHODS: This was a single-center, retrospective study. We included breast cancer patients who underwent NST, had microcalcifications in the post-NST MMG, and underwent surgery from January 2, 2013 to December 30, 2014 at Asan Medical Center. Patients with post-NST MMG as well as MRI were included. Final pathologic tumor size with histopathology and biomarker status were obtained postoperatively. RESULTS: In total, 151 patients were included in this study. Overall, MRI correlated better than MMG in predicting the tumor size (intraclass correlation coefficient [ICC], 0.769 vs. 0.651). For hormone receptor (HR)-positive (HR+)/HER2- subtype, MMG had higher correlation than MRI (ICC = 0.747 vs. 0.575). In HR- subtype, MRI had a strong correlation with pathology (HR-/HER2+ or triple negative (TN), ICC = 0.939 vs. 0.750), whereas MMG tended to overestimate the tumor size (HR-/HER2+ or TN, ICC = 0.543 vs. 0.479). CONCLUSION: Post-NST residual microcalcifications on MMG have a lower correlation with residual tumor size than MRI. Other than HR+/HER2- subtype, the extent of calcifications on preoperative evaluation might not be accurate in evaluating the residual extent of the tumor after NST.


Subject(s)
Breast Neoplasms/diagnostic imaging , Calcinosis/diagnostic imaging , Magnetic Resonance Imaging/methods , Mammography/methods , Neoplasm, Residual/diagnostic imaging , Adult , Aged , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Calcinosis/pathology , Chemotherapy, Adjuvant , Female , Humans , Middle Aged , Neoadjuvant Therapy , Neoplasm, Residual/pathology , Retrospective Studies
14.
Acta Radiol ; 59(5): 527-532, 2018 May.
Article in English | MEDLINE | ID: mdl-28766978

ABSTRACT

Background Only few studies have assessed variability in the results obtained by the readers with different experience levels in comparison with automated volumetric breast density measurements. Purpose To examine the variations in breast density assessment according to BI-RADS categories among readers with different experience levels and to compare it with the results of automated quantitative measurements. Material and Methods Density assignment was done for 1000 screening mammograms by six readers with three different experience levels (breast-imaging experts, general radiologists, and students). Agreement level between the results obtained by the readers and the Volpara automated volumetric breast density measurements was assessed. The agreement analysis using two categories-non-dense and dense breast tissue-was also performed. Results Intra-reader agreement for experts, general radiologists, and students were almost perfect or substantial (k = 0.74-0.95). The agreement between visual assessments of the breast-imaging experts and volumetric assessments by Volpara was substantial (k = 0.77). The agreement was moderate between the experts and general radiologists (k = 0.67) and slight between the students and Volpara (k = 0.01). The agreement for the two category groups (nondense and dense) was almost perfect between the experts and Volpara (k = 0.83). The agreement was substantial between the experts and general radiologists (k = 0.78). Conclusion We observed similar high agreement levels between visual assessments of breast density performed by radiologists and the volumetric assessments. However, agreement levels were substantially lower for the untrained readers.


Subject(s)
Breast Density , Mammography , Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Observer Variation , Radiographic Image Interpretation, Computer-Assisted/methods , Retrospective Studies , Software
15.
Breast Cancer Res Treat ; 165(1): 119-128, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28577079

ABSTRACT

PURPOSE: To assess the diagnostic performance of unenhanced abbreviated protocol (AP) comprising fused diffusion-weighted imaging (DWI) using T1-weighted imaging (T1WI) with DWI maximum-intensity projections (DWI MIPs) for screening patients with a personal history of breast cancer (PHBC). METHODS: This institutional review board-approved retrospective observational study included 343 patients with PHBC who underwent 3T breast magnetic resonance imaging (MRI) between November 2013 and September 2015. Three breast radiologists reviewed the DWI MIPs of the AP to identify lesions, and the remaining axial AP images to characterize the detected lesions and establish the breast imaging reporting and data system final assessment. The conventional protocol (CP) images were also evaluated in the same way. The decision-making times were recorded. RESULTS: MRI acquisition time was approximately 5 min for AP. The mean times to read MIPs and remaining images were shorter in AP than in CP (5.5 and 22.1 s vs. 7.8 and 29.6 s). On DWI MIPs, the readers detected 9, 8, and 9 of 9 pathologically proven cancers, with negative predictive values (NPVs) of 100.0, 99.6, and 100.0%. Complete AP showed sensitivities of 88.9, 100.0, and 88.9% and specificities of 94.8, 93.4, and 95.1%. Complete CP showed sensitivities of 100.0, 100.0, and 88.9% and specificities of 93.4, 94.0, and 96.3%. CONCLUSIONS: An unenhanced AP had a short acquisition time of 5 min, and DWI MIPs showed NPVs greater than 99% across readers. The diagnostic performance of complete AP was equivalent to that of CP for screening patients with PHBC.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/surgery , Diffusion Magnetic Resonance Imaging/methods , Image Interpretation, Computer-Assisted/methods , Mastectomy , Neoplasm Recurrence, Local/diagnostic imaging , Adult , Aged , Biopsy , Contrast Media/administration & dosage , Female , Humans , Middle Aged , Observer Variation , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Time Factors , Treatment Outcome
16.
J Korean Med Sci ; 31 Suppl 1: S32-7, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26908985

ABSTRACT

We retrospectively reviewed the thoracic CT scan protocols and technical parameters obtained from hospitals in Korea, one group during May 2007 (n = 100) and the other group during January 2012 (n = 173), before and after the establishment of the thoracic CT Guideline in 2008. Each group was also divided into two subgroups according to the health care delivery level, i.e. the "A" subgroup from primary and the "B" subgroup from secondary and tertiary care hospitals. When comparing the data from 2007 and 2012, the tube current decreased from 179.1 mAs to 137.2 mAs. The scan interval decreased from 6.4 mm to 4.8 mm. Also, the insufficient scan range decreased from 19.0% to 8.7%, and the suboptimal quality scans decreased from 33.0% to 5.2%. Between groups A and B, group B had lower tube voltages, smaller scan thicknesses, and smaller scan intervals. However, group B had more phase numbers. In terms of the suboptimal quality scans, a decrease was seen in both groups. In conclusion, during the five-year time period between 2007 and 2012, a reduction in the tube current values was seen. And the overall image quality improved over the same time period. We assume that these changes are attributed to the implementation of the thoracic CT guideline in 2008.


Subject(s)
Radiography, Thoracic , Tomography, X-Ray Computed , Asian People , Guidelines as Topic , Hospitals , Humans , Image Processing, Computer-Assisted , Radiation Dosage , Republic of Korea , Retrospective Studies , Societies, Scientific , Surveys and Questionnaires , Tomography, X-Ray Computed/instrumentation
17.
Korean J Anesthesiol ; 67(2): 110-4, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25237447

ABSTRACT

BACKGROUND: The efficacy of palonosetron in preventing postoperative nausea and vomiting (PONV), as well as chemotherapy-induced nausea and vomiting, has already been demonstrated in multiple clinical studies. The purpose of this study was to determine whether continuous infusion of palonosetron following single injection could reduce PONV to a greater extent than single injection only of palonosetron. METHODS: In total, 132 women were enrolled in the study. All subjects were over the age of 20 years and were scheduled to undergo gynecologic laparoscopic surgery. Patients were randomly allocated into two groups. In both groups, patients received 0.075 mg of palonosetron intravenously, immediately before induction of anesthesia. In the continuous palonosetron infusion group, 0.075 mg (1.5 ml) of palonosetron was added to the patient-controlled analgesia device. In the single-injection palonosetron group, 1.5 ml of normal saline was added. RESULTS: The incidence of PONV 24 hours postoperatively was significantly lower in the continuous palonosetron infusion group than the single-injection palonosetron group (31.8 vs. 56.1%, P = 0.009). CONCLUSIONS: Continuous palonosetron infusion, following single injection, reduces the incidence of PONV compared with single injection only.

18.
Elife ; 3: e02630, 2014 Jun 24.
Article in English | MEDLINE | ID: mdl-24963140

ABSTRACT

Hybrid sterility is one of the earliest postzygotic isolating mechanisms to evolve between two recently diverged species. Here we identify causes underlying hybrid infertility of two recently diverged fission yeast species Schizosaccharomyces pombe and S. kambucha, which mate to form viable hybrid diploids that efficiently complete meiosis, but generate few viable gametes. We find that chromosomal rearrangements and related recombination defects are major but not sole causes of hybrid infertility. At least three distinct meiotic drive alleles, one on each S. kambucha chromosome, independently contribute to hybrid infertility by causing nonrandom spore death. Two of these driving loci are linked by a chromosomal translocation and thus constitute a novel type of paired meiotic drive complex. Our study reveals how quickly multiple barriers to fertility can arise. In addition, it provides further support for models in which genetic conflicts, such as those caused by meiotic drive alleles, can drive speciation.DOI: http://dx.doi.org/10.7554/eLife.02630.001.


Subject(s)
Gene Rearrangement/genetics , Genome, Fungal , Hybridization, Genetic , Meiosis/genetics , Schizosaccharomyces/cytology , Schizosaccharomyces/genetics , Alleles , Aneuploidy , Chromosomes, Fungal/genetics , DNA Breaks, Double-Stranded , DNA Repair/genetics , DNA, Mitochondrial/genetics , Haploidy , Recombination, Genetic/genetics , Schizosaccharomyces/growth & development , Spores, Fungal/physiology
19.
Int J Med Sci ; 11(3): 226-33, 2014.
Article in English | MEDLINE | ID: mdl-24516345

ABSTRACT

BACKGROUND: Pain plays roles in both the nervous system and immune system. Changes in the neuroendocrine pathway under pain conditions give rise to sympathetic outflow with increased plasma catecholamines and activate immune reactions. Dexmedetomidine exerts sedative, analgesic, and anesthetic-sparing effects and is known to diminish pro-inflammatory processes by central sympatholytic effects. To investigate the influence of the analgesic effect of dexmedetomidine on immunomodulation under pain conditions, splenic natural killer (NK) tumoricidal cytotoxic activity, proliferative ability of T lymphocytes, and cytokine changes were assessed. METHODS: After evaluation of the analgesic efficacy of dexmedetomidine in C57BL mice that were subjected to formalin-induced pain, dexmedetomidine (30 µg/kg) or saline was injected intraperitoneally (ip) 30 min before formalin (20 µL of 2% formalin in 0.9% saline) injection. NK cell activity against NK-sensitive YAC-1 lymphoma cells was evaluated by the percentage of specific lactate dehydrogenase (LDH) release. Various numbers of effector cells (NK cells) were added to the wells of a microtiter plate containing 2 × 10(4) target YAC-1 cells in 100 µL, to achieve final effector-to-target cell ratios of 80:1, 40:1, and 20:1. The level of lymphocyte proliferation in response to phytohemagglutinin (PHA) was detected by bromodeoxyuridine (BrdU) incorporation assay. TNF-α, IL-1ß, and IL-10 levels were determined in blood samples and supernatants of splenocyte preparations. RESULTS: IP administration of dexmedetomidine significantly decreased the time of licking and biting during the first and second phases of the formalin test (p <0.001). Formalin-induced pain led to higher activity of NK cells than in sham-treated mice (p <0.05), but NK activity was not increased significantly by ip dexmedetomidine treatment. Formalin-induced pain significantly increased splenic lymphocyte proliferation (p <0.05), but dexmedetomidine did not alter this response. There was a significant increase in plasma TNF-α (p = 0.048) and IL-6 (p = 0.014) levels after formalin-induced pain. However, the differences between the responses after ip dexmedetomidine did not change significantly. CONCLUSIONS: Dexmedetomidine showed antinociceptive effect on both of acute pain phase 1 and hyperalgesic phase 2 of formalin pain model. Formalin-induced pain alters cellular immunity of spleen in mice. Dexmedetomidine attenuates the activation of NK cells under pain condition, but neither the proliferative response of the splenic lymphocytes nor the cytokine production was affected by dexmedetomidine.


Subject(s)
Analgesics/administration & dosage , Dexmedetomidine/administration & dosage , Immunity/drug effects , Pain/drug therapy , Animals , Formaldehyde/toxicity , Interleukin-10/metabolism , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Lymphocytes/immunology , Lymphocytes/metabolism , Mice , Pain/chemically induced , Pain/immunology , Spleen/cytology , Spleen/drug effects
20.
Acta Radiol ; 53(5): 545-50, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22547388

ABSTRACT

BACKGROUND: The decreased portal blood flow and the potential decrease in arterial nutrient hepatic blood flow after creation of a transjugular intrahepatic portosystemic shunt (TIPS) makes the treatment of hepatocellular carcinoma (HCC) challenging. PURPOSE: To evaluate the safety and efficacy of transarterial chemoembolization (TACE) after TIPS in patients with HCC. MATERIAL AND METHODS: From 1998 to 2009, 20 patients underwent selective (segmental or subsegmental) TACE for HCC after TIPS. Among 20 patients, seven patients had undergone one to three sessions of TACE for HCC before TIPS creation. TACE was performed using a mixture of iodized oil and cisplatin, and absorbable gelatin sponge particles. Tumor response, complications, and patient survival were evaluated after TACE. RESULTS: After TACE, 14 of the 20 (70%) patients showed a tumor response, with only one (5%) experiencing a TACE-related major complication, spontaneous bacterial peritonitis. None of the patients who underwent TACE after TIPS died within 30 days. During the follow-up period (range 2.2-107 months; mean 32.6 months), 18 patients died and two remained alive. The median survival period after TACE was 23 months. Multivariate Cox regression analysis showed that tumor stage was the only independent prognostic factor for patient survival (P = 0.049). CONCLUSION: Selective TACE may be safe and effective for the palliative treatment of HCC in patients with TIPS. Late tumor stage ( ≥III) was poor prognostic factor for determining the patient survival period after post-TIPS TACE.


Subject(s)
Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Portasystemic Shunt, Transjugular Intrahepatic , Carcinoma, Hepatocellular/pathology , Cisplatin/administration & dosage , Ethiodized Oil/administration & dosage , Female , Gelatin Sponge, Absorbable/administration & dosage , Humans , Liver Function Tests , Liver Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Prognosis , Proportional Hazards Models , Radiography, Interventional , Stents , Survival Rate , Tomography, X-Ray Computed , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL
...