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Background Atrial arrhythmia, particularly atrial fibrillation (AF), is known to be associated with renal function decline and increased risk of end-stage kidney disease. In recent years, premature atrial complexes (PACs) as subclinical arrhythmia have been proposed to be a marker of atrial cardiomyopathy and associated with poor clinical outcomes. However, the relationship between excessive daily PAC burden and renal outcomes remains unexplored. Methods This retrospective, all-comers cohort study analyzed 30 488 consecutive Holter monitoring records obtained from a validated Holter databank at a referral medical center in Taiwan between 2011 and 2018. After exclusion, 10 981 patients were categorized into three groups: high daily PAC burden (≥100 beats per day), low PAC burden (<100 beats per day) and the AF group. We used parallel propensity score matching to balance confounding factors between groups. The primary study interest was major adverse kidney events, including an estimated glomerular filtration rate (eGFR) decline of 40%, eGFR <15 mL/min/1.73 m2 or the initiation of hemodialysis. Results After a mean follow-up of 4.07 ± 3.03 years, patients with high PAC burden had a 1.24-fold higher incidence of major adverse kidney events compared with the low PAC burden group [95% confidence interval (CI) 1.03–1.50]. The risk of major adverse kidney events was similar between patients with AF and those with high PAC burden [adjusted hazard ratio (HR) 1.05, 95% CI 0.87–1.25], but significantly higher in the AF group than in the low PAC burden group (adjusted HR 1.29, 95% CI 1.07–1.56). Conclusion Excessive daily PAC burden is associated with a higher risk of major adverse kidney events and has a comparable impact as AF. [ABSTRACT FROM AUTHOR]

The Bin–Amphiphysin–Rvs (BAR) domain of endophilin binds to the cell membrane and shapes it into a tubular shape for endocytosis. Endophilin has a Src-homology 3 (SH3) domain at their C-terminal. The SH3 domain interacts with the proline-rich motif (PRM) that is found in proteins such as neural Wiskott–Aldrich syndrome protein (N-WASP). Here, we re-examined the binding sites of the SH3 domain of endophilin in N-WASP by machine learning-based prediction and identified the previously unrecognized binding site. In addition to the well-recognized PRM at the central proline-rich region, we found a PRM in front of the N-terminal WASP homology 1 (WH1) domain of N-WASP (NtPRM) as a binding site of the endophilin SH3 domain. Furthermore, the diameter of the membrane tubules in the presence of NtPRM mutant was narrower and wider than that in the presence of N-WASP and in its absence, respectively. Importantly, the NtPRM of N-WASP was involved in the membrane localization of endophilin A2 in cells. Therefore, the NtPRM contributes to the binding of endophilin to N-WASP in membrane remodeling. [ABSTRACT FROM AUTHOR]

Horizontal transmission of bacteria to varied hosts can maintain and even expand microbial niches. We previously found that the aphid gut bacterium Serratia symbiotica strain SsMj can be transmitted to ladybird beetles via predation, but whether the predator is a new host, a reservoir or a dead end of this bacterium is unknown. This study aims to provide a clear picture of SsMj circulation from aphids to plants and predators. We first found that SsMj in aphids and ladybirds was abundantly distributed not only in digestive tracts but also in droppings. We found no evidence for vertical transmission of SsMj to aphid offspring. Instead, we showed that it could be transmitted to conspecific aphids by sharing the same plant or contacting honeydews. The key finding of this study is that SsMj was transmitted from aphids to ladybirds through predation, while ladybirds could also transfer SsMj back to aphids, possibly through feces. Together, this evidence suggests that SsMj is able to survive in the digestive tracts and droppings of insects and to expand its host range with plants and predators as reservoirs. [ABSTRACT FROM AUTHOR]

Objectives Perceiving simultaneity of a visual and an auditory signal is critical for humans to integrate these multisensory inputs effectively and respond properly. We examined age-related changes in audiovisual simultaneity perception, and the relationships between this perception and working memory performances with aging. Methods Audiovisual simultaneity perception of young, middle-aged, and older adults was measured using a simultaneity judgment (SJ) task, in which a flash and a beep were presented at 1 of 11 stimulus-onset asynchronies (SOAs). Participants judged whether these two stimuli were perceived simultaneously. Precision of simultaneity perception, the SOA corresponding to the point of subjective simultaneity (PSS), and response errors at each SOA were estimated using model fitting. The precision and PSS are associated with multisensory perception per se, whereas the response error reflects executive ability when performing the SJ task. Visual working memory of the same middle-aged and older adults was measured using the Cambridge Neuropsychological Test Automated Battery (CANTAB) beforehand. Results Compared to young adults' performances, middle-aged and older adults showed a decreased precision, a shift of PSS toward the visual-leading SOAs, and increased response errors at the visual-leading SOAs. Among these changes, only the increased response errors correlated with worse spatial recognition memory in middle-aged and older adults. Discussion Age-related decrements in audiovisual simultaneity perception start from middle age and are manifested in both perceptual and executive parameters. Furthermore, higher-order executive ability is plausibly a common cause for age-related degenerations in the audiovisual simultaneity perception and visual working memory. [ABSTRACT FROM AUTHOR]

In long‐term clinical studies, recurrent event data are sometimes collected and used to contrast the efficacies of two different treatments. The event reoccurrence rates can be compared using the popular negative binomial model, which incorporates information related to patient heterogeneity into a data analysis. For treatment allocation, a balanced approach in which equal sample sizes are obtained for both treatments is predominately adopted. However, if one treatment is superior, then it may be desirable to allocate fewer subjects to the less‐effective treatment. To accommodate this objective, a sequential response‐adaptive treatment allocation procedure is derived based on the doubly adaptive biased coin design. Our proposed treatment allocation schemes have been shown to be capable of reducing the number of subjects receiving the inferior treatment while simultaneously retaining a test power level that is comparable to that of a balanced design. The redesign of a clinical study illustrates the advantages of using our procedure. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae is an important human pathogen causing hospital-acquired and community-acquired infections. Systemic K. pneumoniae infections may be preceded by gastrointestinal colonization, but the basis of this bacterium's interaction with the intestinal epithelium remains unclear. Here, we report that the K. pneumoniae Sap (sensitivity to antimicrobial peptides) transporter contributes to bacterial-host cell interactions and in vivo virulence. Gene deletion showed that sapA is required for the adherence of a K. pneumoniae blood isolate to intestinal epithelial, lung epithelial, urinary bladder epithelial, and liver cells. The ΔsapA mutant was deficient for translocation across intestinal epithelial monolayers, macrophage interactions, and induction of proinflammatory cytokines. In a mouse gastrointestinal infection model, ΔsapA yielded significantly decreased bacterial loads in liver, spleen and intestine, reduced liver abscess generation, and decreased mortality. These findings offer new insights into the pathogenic interaction of K. pneumoniae with the host gastrointestinal tract to cause systemic infection. [ABSTRACT FROM AUTHOR]

Background: We previously isolated a Klebsiella pneumoniae strain, NTUH-K2044, from a community-acquired pyogenic liver abscess (PLA) patient. Analysis of the NTUH-K2044 genome revealed that this strain harbors 2 putative type VI secretion system (T6SS)-encoding gene clusters.Methods: The distribution of T6SS genes in the PLA and intestinal-colonizing K pneumoniae clinical isolates was examined. icmF1-, icmF2-, icmF1/icmF2-, and hcp-deficient K pneumoniae strains were constructed using an unmarked deletion method. The roles of T6SSs in antibacterial activity, type-1 fimbriae expression, cell adhesion, and invasion and intestinal colonization were determined.Results: The prevalence of T6SSs is higher in the PLA strains than in the intestinal-colonizing strains (37 of 42 vs 54 of 130). Deletion of icmF1/icmF2 and hcp genes significantly reduced interbacterial and intrabacterial killing. Strain deleted for icmF1 and icmF2 exhibited decreased transcriptional expression of type-1 fimbriae and reduced adherence to and invasion of human colorectal epithelial cells and was attenuated for in vivo competition to enable colonization of the host gut. Finally, Hcp expression in K pneumoniae was silenced by the histone-like nucleoid structuring protein via direct binding.Conclusions: These results provide new insights into T6SS-mediated bacterial competition and attachment in K pneumoniae and could facilitate the prevention of K pneumoniae infection. [ABSTRACT FROM AUTHOR]

Background: This study evaluated the efficiency of corticosteroid, leflunomide and mesenchymal stem cells (MSCs) in the treatment of pediatric idiopathic pulmonary hemosiderosis (IPH). Methods: Ten patients were included in the study. The diagnosis of IPH was based on clinical symptoms, laboratory examinations and pulmonary hemosiderosis. Induction therapy consisted of methylprednisolone pulse therapy, followed by prednisone plus leflunomide. Maintenance therapy consisted of low-dose prednisone, leflunomide and administration of MSCs. Results: All the patients achieved complete response after treatment with corticosteroid, leflunomide and MSCs. The median follow-up was 23 months (range: 4-34 months). Moreover, administration of MSCs induced an increase in the percentage of CD4+ CD25+ regulatory T cells but a decrease in the percentage of Th17 cells. Conclusion: Treatment with corticosteroid, leflunomide and MSCs for pediatric IPH was safe and effective. [ABSTRACT FROM AUTHOR]

Background. Dual-task Timed "Up & Go" (TUG) tests are likely to have applications different from those of a single-task TUG test and may have different contributing factors. Objective. The purpose of this study was to compare factors contributing to performance on single- and dual-task TUG tests. Design. This investigation was a cross-sectional study. Methods. Sixty-four adults who were more than 50 years of age and dwelled in the community were recruited. Interviews and physical examinations were performed to identify potential contributors to TUG test performance. The time to complete the single-task TUG test (TUGsingle) or the dual-task TUG test, which consisted of completing the TUG test while performing a serial subtraction task (TUGcognitive) or while carrying water (TUGmanual), was measured. Results. Age, hip extensor strength, walking speed, general mental function, and Stroop scores for word and color were significantly associated with performance on all TUG tests. Hierarchical multiple regression models, without the input of walking speed, revealed different independent factors contributing to TUGsingle performance (Mini-Mental Status Examination score, β=-0.32), TUGmanual performance (age, β=0.35), and TUGcognitive performance (Stroop word score, β=- 0.40; Mini-Mental Status Examination score, β=0.31). Limitations. At least 40% of the variance in the performance on the 3 TUG tests was not explained by common clinical measures, even when the factor of walking speed was considered. However, this study successfully identified some important factors contributing to performance on different TUG tests, and other studies have reported similar findings for single-task TUG test and dual-task gait performance. Conclusions. Although the TUGsingle and the TUGcognitive shared general mental function as a common factor, the TUGmanual was uniquely influenced by age and the TUGcognitive was uniquely influenced by focused attention. These results suggest that both common and unique factors contribute to performance on single- and dual-task TUG tests and suggest important applications of the combined use of the 3 TUG tests. [ABSTRACT FROM AUTHOR]

In this study of Arabidopsis (Arabidopsis thaliana), we investigated the relationship between FOREVER YOUNG FLOWER (FYF) and Ethylene Response DNA-binding Factors (EDFs) and functionally analyzed a key FYF target, an Ethylene-Responsive Factor (ERF), that controls flower senescence/abscission. Ectopic expression of EDF1/2/3/4 caused promotion of flower senescence/ abscission and the activation of the senescence-associated genes. The presence of a repressor domain in EDFs and the enhancement of the promotion of senescence/abscission in EDF1/2/3/4+SRDX (converting EDFs to strong repressors by fusion with the ERF-associated amphiphilic repression motif repression domain SRDX) transgenic plants suggested that EDFs act as repressors. The significant reduction of b-glucuronidase (GUS) expression by 35S:FYF in EDF1/2/3/4:GUS plants indicates that EDF1/2/3/4 functions downstream of FYF in regulating flower senescence/abscission. In this study, we also characterized an ERF gene, FOREVER YOUNG FLOWER UP-REGULATING FACTOR1 (FUF1), which is up-regulated by FYF during flower development. Ectopic expression of FUF1 caused similar delayed flower senescence/abscission as seen in 35S:FYF plants. This phenotype was correlated with deficient abscission zone formation, ethylene insensitivity, and down-regulation of EDF1/2/3/4 and abscission-associated genes in 35S:FUF1 flowers. In contrast, significant promotion of flower senescence/abscission and up-regulation of EDF1/2/3/4 were observed in 35S:FUF1+SRDX transgenic dominant-negative plants, in which FUF1 is converted to a potent repressor by fusion to an SRDX-suppressing motif. Thus, FUF1 acts as an activator in suppressing EDF1/2/3/4 function and senescence/abscission of the flowers. Our results reveal that FYF regulates flower senescence/ abscission by negatively regulating EDF1/2/3/4, which is the downstream gene in the ethylene response, by activating FUF1 in Arabidopsis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Klebsiella pneumoniae causing community-acquired pyogenic liver abscess complicated with metastatic meningitis and endophthalmitis has emerged recently, most frequently associated with the K1 capsular type. METHODS: A bacteriophage (NTUH-K2044-K1-1) that infects K. pneumoniae NTUH-K2044 (capsular type K1) was isolated and characterized. RESULTS: The phage infected all K1 strains, and none of the strains with other capsular types. Capsule deletion mutants were not lysed by this phage, suggesting that the capsule was essential for phage infection. Complete genome sequencing revealed the phage was a novel phiKMV-like virus. The gene-encoding capsule depolymerase was identified. The recombinant enzyme demonstrated specific lysis of the K1 capsule. Treatment with the phage or the recombinant enzyme provided significantly increased survival in mice infected with NTUH-K2044 strain, including one treated after the detection of a neck abscess by imaging. No obvious disease was observed after administration of this phage in mice. Phage was retained at detectable levels in liver, spleen, brain, and blood 24 hours after administration in mice. CONCLUSIONS: These results demonstrate this phage and its capsule depolymerase exhibit specificity for capsular type K1 and can be used for the diagnosis and treatment of K1 K. pneumoniae infections. [ABSTRACT FROM AUTHOR]

Background. Peptidoglycan-associated lipoprotein (Pal), murein lipoprotein (LppA), and outer membrane protein A (OmpA) are dominant outer membrane proteins (OMPs) that are released by gram-negative bacteria during sepsis. OMPs are implicated in the maintenance of cell envelope integrity. Here, we characterize the roles of these OMPs in pathogenesis during bacteremia caused by Klebsiella pneumoniae.Methods. pal-, lppA-, and ompA-deficient K. pneumoniae strains were constructed using an unmarked deletion method. Serum sensitivity, antiphagocytosis activity, outer membrane permeability, and sensitivity to anionic detergents and antimicrobial polypeptides were determined for these OMP gene deletion mutants. The ability of these OMP gene deletion mutants to induce immune responses was compared with that of the wild-type strain in a bacteremic mouse model.Results. Klebsiella pneumoniae strains deleted for pal or lppA exhibited reduced protection from serum killing and phagocytosis; perturbation to the outer membrane permeability barrier and hypersensitivity to bile salts and sodium dodecyl sulfate. The strain mutated for lppA had reduced ability to activate Toll-like receptor 4. Immunization of mice with the pal or lppA mutant provided protection against infection by the wild-type strain.Conclusions. Our findings indicate that K. pneumoniae Pal and LppA proteins are important in the maintenance of cell integrity, contribute to virulence, and could be used as attenuated vaccines. [ABSTRACT FROM AUTHOR]

Gynostemium and ovule development in orchid are unique developmental processes in the plant kingdom. Characterization of C- and D-class MADS-box genes could help reveal the molecular mechanisms underlying gynostemium and ovule development in orchids. In this study, we isolated and characterized a C- and a D-class gene, PeMADS1 and PeMADS7, respectively, from Phalaenopsis equestris. These two genes showed parallel spatial and temporal expression profiles, which suggests their cooperation in gynostemium and ovule development. Furthermore, only PeMADS1 was ectopically expressed in the petals of the gylp (gynostemium-like petal) mutant, whose petals were transformed into gynostemium-like structures. Protein–protein interaction analyses revealed that neither PeMADS1 and PeMADS7 could form a homodimer or a heterodimer. An E-class protein was needed to bridge the interaction between these two proteins. A complementation test revealed that PeMADS1 could rescue the phenotype of the AG mutant. Overexpression of PeMADS7 in Arabidopsis caused typical phenotypes of the D-class gene family. Together, these results indicated that both C-class PeMADS1 and D-class PeMADS7 play important roles in orchid gynostemium and ovule development. [ABSTRACT FROM PUBLISHER]

Background. Five components of metabolic syndrome (MetS) have been identified as predictive of cardiovascular events (CVEs) in the general population: impaired fasting glucose, abdominal obesity, hypertriglyceridemia, hypertension and low high-density lipoprotein cholesterol. Whether MetS and its components are also predictive of CVEs in chronic hemodialysis (HD) patients remains unclear. We therefore investigated the role of MetS and its components in patients on chronic HD.Methods. MetS at baseline was diagnosed in 91 HD patients based on the American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI) and the International Diabetes Federation (IDF) definitions. During a 3-year period, all hospitalizations, CVEs and deaths were recorded and analyzed using Kaplan–Meier survival analysis and Cox regression.Results. There were no differences in the number of CVEs, hospitalizations or deaths between patients with and without AHA/NHLBI-defined MetS; however, patients with IDF-defined MetS were found to be at a higher risk for CVEs (P = 0.006). Cox regression analysis showed that, of the MetS components, abdominal obesity was the single most significant predictor of CVEs (hazard ratio 6.25; 95% confidence interval: 1.65–23.6; P = 0.007).Conclusions. IDF-defined MetS was more predictive of CVEs than AHA/NHLBI-defined MetS. Of the MetS components, abdominal obesity was the single most significant predictor of CVEs in chronic HD patients. [ABSTRACT FROM AUTHOR]

The orchid floral organs represent novel and effective structures for attracting pollination vectors. In addition, to avoid inbreeding, the androecium and gynoecium are united in a single structure termed the gynostemium. Identification of C-class MADS-box genes regulating reproductive organ development could help determine the level of homology with the current ABC model of floral organ identity in orchids. In this study, we isolated and characterized two C-class AGAMOUS-like genes, denoted CeMADS1 and CeMADS2, from Cymbidium ensifolium. These two genes showed distinct spatial and temporal expression profiles, which suggests their functional diversification during gynostemium development. Furthermore, the expression of CeMADS1 but not CeMADS2 was eliminated in the multitepal mutant whose gynostemium is replaced by a newly emerged flower, and this ecotopic flower continues to produce sepals and petals centripetally. Protein interaction relationships among CeMADS1, CeMADS2 and E-class PeMADS8 proteins were assessed by yeast two-hybrid analysis. Both CeMADS1 and CeMADS2 formed homodimers and heterodimers with each other and the E-class PeMADS protein. Furthermore, transgenic Arabidopsis plants overexpressing CeMADS1 or CeMADS2 showed limited growth of primary inflorescence. Thus, CeMADS1 may have a pivotal C function in reproductive organ development in C. ensifolium. [ABSTRACT FROM AUTHOR]

Background. To explore the mechanisms that enable Klebsiella pneumoniae to survive in the gastrointestinal tract, we characterized the roles of the cad and tdc operons during the bacterial response to acid and bile stress. Methods. The transcriptional units of the cad and tdc loci were identified by reverse-transcription polymerase chain reaction (RT-PCR). Transcriptional regulation of the cad and tdc operons under either acid or bile stress was analyzed by real-time RT-PCR. The ability of the mutant strains to colonize the gastrointestinal tract was examined through competition with the wild-type strain during intragastric infection of mice. Results. The cad and tdc operons were single transcriptional units. The NTUH-K2044 wild-type strain displayed an acid tolerance response to inorganic acid and was able to survive in bile encountered in vivo. Altered transcription of the cad and tdc operons by acid depended on CadC. Under either bile stress or acidic conditions, the transcriptional regulation of the tdc operon depended on TdcA. Both the cadCBA and the tdcABCDE mutant strains were impaired in their ability to colonize the mouse intestine, compared with that of the wild-type strain. Conclusion. These results suggest that the cad and tdc loci in K. pneumoniae are involved in the adaptation of the organism to gastrointestinal stress and intestinal colonization. [ABSTRACT FROM AUTHOR]

Background. Klebsiella pneumoniae has become the predominant pathogen causing primary pyogenic liver abscess (PLA). Methods. K. pneumoniae was stimulated by human serum, and gene expression was analyzed by microarray. Results. Three putative iron acquisition systems, Yersinia high-pathogenicity island (HPI), iucABCDiutA, and iroA(iroNDCB), that increased in expression and predominated in PLA-associated K. pneumoniae strains were identified. By use of siderophore uptake assays, these 3 systems were confirmed to be siderophore-dependent iron acquisition systems. Only the irp2-iuc-iroA triple mutant showed decreased virulence in mice. Full-genome analysis of K. pneumoniae strain NTUH-K2044 identified 10 putative iron uptake systems. Seven of these 10 systems were TonB dependent, including Yersinia HPI, iucABCDiutA, and iroA. A tonB deletion mutant was demonstrated to have profound attenuation of virulence. Immunization with the tonB mutant resulted in seroconversion of extracellular polysaccharide antibodies and protective efficacy against subsequent exposure to the parental strain. Conclusions. Iron uptake systems were the genes in K. pneumoniae that were highly up-regulated in response to sera. Although there are multiple iron transporter systems in NTUH-K2044, a mutation in all 3 loci (irp2, iuc, and iroA) is necessary to decrease virulence. The tonB mutant is a potential vaccine candidate because it can induce a significant protective immune response against challenge with a wild-type strain. [ABSTRACT FROM AUTHOR]

In this study, we isolated and characterized the function of a GLOBOSA/PISTILLATA-like gene, PeMADS6, from a native Phalaenopsis species, P. equestris. Southern blot analysis showed PeMADS6 as a single copy in the Phalaenopsis genome. Results of the determination of temporal and spatial expression showed that PeMADS6 was expressed and thus participated in the development of the sepals, petals, labellum and column in Phalaenopsis. Further confirmation of the expression pattern of PeMADS6 was carried out with in situ hybridization. Repressed expression of PeMADS6 in the orchid ovary was found to be pollination regulated, which suggests that the gene may have an inhibitory effect on the development of the ovary or ovule. In addition, auxin acted as the candidate signal to regulate the repression of PeMADS6 expression in the ovary. Furthermore, the flowers of transgenic Arabidopsis plants ectopically overexpressing PeMADS6 showed the morphology of petaloid sepals, with a 3- to 4-fold increase in flower longevity. Concomitantly, delayed fruit maturation was also observed in the transgenic Arabidopsis, which is consistent with the inhibitory effect of PeMADS6 on the development of the ovary. Thus, as a B-function gene, PeMADS6, not only specifies floral organ identity but has functions in flower longevity and ovary development in orchids. [ABSTRACT FROM AUTHOR]

The potential for bioterrorism involving smallpox has led to a debate about the durability of protective immunity against smallpox from vaccination. By assessing the T cell reactivity to vaccinia virus in a healthy population, we show that subjects who were vaccinated within the past 3 decades and who have a visible vaccination scar had remarkable T cell reactivity. However, person who were vaccinated within the past 3 decades but who do not have a scar and those who were vaccinated 14 decades ago had responses as low as those in unvaccinated subjects. Thus, we estimate that the significant T cell memory response to vaccinia virus from successful vaccination may persist for only 20-30 years. Furthermore, we found the vaccinia-specific cellular immunity could be easily assessed by determination of the frequencies of vaccinia-specific CD69 expression on T cell subsets. These data may help in the development of public health strategies to counter bioterrorism threats associated with smallpox. [ABSTRACT FROM AUTHOR]

Background: Phase-dependent modulation of postural responses plays an important functional role in integrating reflexes into ongoing locomotion behaviors. This study tested the hypotheses that proximal and distal postural responses are modulated differently according to the phases of the gait cycle in young adults and that there is a decline in this modulatory ability with normal aging.Methods: Thirty-three healthy young adults (age = 25 +/- 4 years) and 32 healthy older adults (mean age 74 +/- 14 years) participated. Subjects walked across a movable force plate with its movement timed to heel strike or midstance to simulate a forward slip occurring at different times during the gait cycle. Surface electromyography was recorded from bilateral leg, thigh, hip, and trunk muscles. Kinematic data were collected from the right (perturbed) side of the body.Results: Postural responses to the heel strike slips occurred more frequently, and were of shorter latency, longer burst duration, and greater burst magnitude, than those in response to the midstance slips. Whereas the early and predominant postural responses came from bilateral tibialis anterior, rectus femoris, and biceps femoris muscles in heel strike slips, early postural responses were observed in bilateral erector spinae muscles in midstance slips. The late postural responses in midstance slips (from bilateral biceps femoris muscles and medial gastrocnemius and tibialis anterior of the nonperturbed leg) assisted in foot liftoff of the perturbed leg and earlier and safe landing with the nonperturbed leg. In response to the heel strike versus midstance slips, older adults preserved the phase-dependent modulatory abilities of the occurrence, onset latency, and burst duration of their postural responses, but not the ability to modulate burst magnitude, as compared to young adults.Conclusion: Postural responses from the proximal and distal muscles in reaction to different temporal phasing of slips during the step cycle showed differential modulation to meet the different task requirements. Older adults preserve this modulatory ability but with limited capacity. Physiological or psychological factors may influence older adults' phase-dependent modulatory capacity. [ABSTRACT FROM AUTHOR]

Presents a study on inefficient postural responses to unexpected slips during walking in older adults. One primary reason that older adults frequently fall; Method used in the study; Discussion on the results.

Presents an article from the `Physical Therapy' periodical, which highlights the unique nature of balance control during walking in humans. Previous research on balance control in the older adult population; Biomechanical challenges to balance control in bipedal human locomotion; Reasons for maintaining the upright posture of the upper body.

Presents information on a study which investigated the correlation between the performance of older adults on Sensory-Oriented Mobility Assessment Instrument and on various sensory conditions of Sensory Organization Test. Methods used in the study; Results; Conclusions.

Previous work has shown that 7,12-dimethylbenz []anthracene (DMBA)–DNA adducts can be converted by P-post-labeling to different types of radiolabeled derivatives (nucleoside 3′,5′-bisphosphates, nucleoside 5′-monophosphates and dinucleotides), and that the 3′,5′-bisphosphate derivatives can be further characterized by cross-referencing with H-labeled nucleoside DMBA adducts, for which structural information is available. This work has now been extended by TLC comparisons of 5′-monophosphate and 3′,5′-bisphosphate DMBA adducts. To this end, DMBA modified DNA was enzymatically hydrolyzed to 3′-mono-phosphates (Xp+Np) or to dinucleotides (XpN), and these digestion products were P-postlabeled by published procedures to yield 3′,5′-bisphosphate (pXp) or 5′-monophosphate (pX) adducts. Individual pXp and pX fractious were isolated from polyethyleneimine (PEI)–cellulose TLC maps and chromatographically compared after enzymatic 3′-dephosphorylations of the 3′,5′-bisphosphate (pXp) derivatives (pXp→pX+P) Four reactions were standardized and employed for this purpose: (i) 3′-dephos-phorylation by extensive digestion with nuclease P1; (ii) 3′-dephosphorylation catalyzed by polynucleotide kinase; (iii) partial dephosphorylation by bacterial alkaline phosphatase; and (iv) partial dephosphorylation by prostatic acid phos phatase. Individual DMBA adducts displayed marked differences with regard to their susceptibility to enzymatic dephosphorylation. The three major and most minor post-labeled 5′-monophosphate DMBA adducts were cross-referenced this way with 3′,5′-bisphosphate and nucleoside adducts, so that specific dihydrodiol epoxide–nucleoside 5′-monophosphate adducts can now be identified and measured by P-postlabeling. [ABSTRACT FROM PUBLISHER]

Candidate malaria vaccines have failed to elicit consistently protective immune responses against challenge with Plasmodium falciparum. NYVAC-Pf7, a highly attenuated vaccinia virus with 7 P. falciparum genes inserted into its genome, was tested in a phase I/IIa safety, immunogenicity, and efficacy vaccine trial in human volunteers. Malaria genes inserted into the NYVAC genome encoded proteins from all stages of the parasite's life cycle. Volunteers received three immunizations of two different dosages of NYVAC-Pf7. The vaccine was safe and well tolerated but variably immunogenic. While antibody responses were generally poor, cellular immune responses were detected in >90% of the volunteers. Of the 35 volunteers challenged with the bite of 5 P. falciparum-infected Anopheles mosquitoes, 1 was completely protected, and there was a significant delay in time to parasite patency in the groups of volunteers who received either the low or high dose of vaccine compared with control volunteers. [ABSTRACT FROM PUBLISHER]