Search

Although recent technological advances in DNA sequencing and computational biology now allow scientists to compare entire microbial genomes, comparisons of closely related bacterial species and individual isolates by whole-genome sequencing approaches remains prohibitively expensive for most laboratories. Here we report the development and testing of a biochemical approach for targeted sequencing of only those chromosomal regions that differ between two DNA preparations. The method, designated GFE (genome fragment enrichment) uses competitive solution hybridization and positive selection to obtain genomic DNA fragments that are present in one pool of fragments but not another. Repeated comparisons of the genomes of Enterococcus faecalis and E. faecium led to the identification of 225 putative genome-specific DNA fragments. Species and strain variations within these fragments were confirmed by both experimental and bioinformatic analyses. The E. faecalis genome-specific sequences identified included both a preponderance of those predicted to encode surface-exposed proteins, as well as several previously described unique marker regions embedded within highly conserved rrn operons. The GFE strategy we describe efficiently identified genomic differences between two enterococcal genomes, and will be widely applicable for studying genetic variation among closely related bacterial species.

Several PCR methods have recently been developed to identify fecal contamination in surface waters. In all cases, researchers have relied on one gene or one microorganism for selection of host-specific markers. Here we describe the application of a genome fragment enrichment (GFE) method to identify host-specific genetic markers from fecal microbial community DNA. As a proof of concept, bovine fecal DNA was challenged against a porcine fecal DNA background to select for bovine-specific DNA sequences. Bioinformatic analyses of 380 bovine enriched metagenomic sequences indicated a preponderance of Bacteroidales -like regions predicted to encode membrane-associated and secreted proteins. Oligonucleotide primers capable of annealing to select Bacteroidales -like bovine GFE sequences exhibited extremely high specificity (>99%) in PCR assays with total fecal DNAs from 279 different animal sources. These primers also demonstrated a broad distribution of corresponding genetic markers (81% positive) among 148 different bovine sources. These data demonstrate that direct metagenomic DNA analysis by the competitive solution hybridization approach described is an efficient method for identifying potentially useful fecal genetic markers and for characterizing differences between environmental microbial communities.

The induction of virulence traits by Legionella pneumophila at the post-exponential phase has been proposed to be triggered by the stringent response mediated by RelA, which triggers RpoS. We show that L. pneumophila rpoS but not relA is required for early intracellular survival and replication within human monocyte-derived macrophages and Acanthamoeba polyphaga . In addition, L. pneumophila rpoS but not relA is required for expression of the pore-forming activity. We provide evidence that RpoS plays a role in the modulation of phagosome biogenesis and in adaptation to the phagosomal microenvironment. Thus, there is no functional link between the stringent response and RpoS in the pathogenesis of L. pneumophila .

Arylamine N-acetyltransferases (NAT; EC 2.3.1.5) catalyse the transfer of acetyl groups from acetylCoA to xenobiotics, including drugs and carcinogens. The enzyme is found extensively in both eukaryotes and prokaryotes, yet the endogenous roles of NATs are still unclear. In order to study the properties of eukaryotic NATs, high-throughput substrate and inhibitor screens have been developed using pure soluble recombinant Syrian hamster NAT2 (shNAT2) protein. The assay can be used with a wide range of compounds and was used to determine substrate specificity of shNAT2. We describe the expression and characterisation of shNAT2 and also purified recombinant human NAT1 and NAT2, including the use of the assay to explore the substrate specificities of each of the enzymes. Hamster NAT2 has similar substrate specificity to human NAT1, acetylating para-aminobenzoate but not arylhydrazine and hydralazine compounds. The overlapping but distinct substrate-specific activity profiles of human NAT1 and NAT2 were clearly observed from the screen. Naturally occurring compounds were tested as substrates or inhibitors of shNAT2 and succinylCoA was found to be a potent inhibitor of shNAT2.

The bacteriophage lambda tR1 terminator encodes a region of the nascent cro transcript containing RNA residues recognized by termination factor Rho. To identify ribonucleotide-protein interactions contributing to termination, a library of reporter gene plasmids was constructed containing predominantly single-nucleotide substitutions in a 24 nt region previously shown to be critical for efficient termination. Screening 16 822 bacterial transformants identified 110 terminator mutants, most of which contained two or more nucleotide substitutions. Although the vast majority of single base changes did not reduce tR1 function, 11 specific single-nucleotide substitutions at eight positions interspersed in the upstream part of the target region (5'-ATAACCCCGCTCTT ACACATTCCA-3') did reduce termination. About half of these substitutions also reduced Rho-dependent termination on cro gene templates transcribed by purified RNA polymerase, indicating specific residues critical for optimal terminator function. Other termination defects were not reproduced in these in vitro assays, and likely resulted from indirect effects of altering interactions between tR1 and additional cellular factors capable of attenuating Rho function. Our results indicate that while Rho is able to recognize a wide variety of similar rut site sequences by interacting with alternate nucleotides at critical positions, interactions with specific individual ribonucleotides of the tR1 transcript provide highly efficient Rho-dependent termination.

Background & Aims: Helicobacter pylori inhabits a highly restricted ecological niche in the human gastric mucosa. Microbial gene expression in the context of persistent infection remains largely uncharacterized. Methods: An RNA analysis method, selective capture of transcribed sequences, was used in conjunction with genomic array hybridization to characterize H. pylori complementary DNAs (cDNAs) obtained from both human and experimentally infected gerbil gastric tissue specimens. Results: Bacterial cDNAs obtained by selective capture of transcribed sequences from tissues hybridized to arrayed DNA fragments representing approximately 70% of open reading frames in the H. pylori genome. RNAs for most of these open reading frames were also detected by array hybridization analyses of total RNA prepared from the isolated H. pylori strains cultured in vitro. However, a subset of H. pylori RNAs detected in gastric tissue specimens was consistently undetectable in bacteria grown in vitro. The majority of these RNAs encode factors unique to H. pylori that are potentially produced in response to interactions with mammalian gastric mucosa. Conclusions: The combination of selective capture of transcribed sequences with array hybridization has allowed a global analysis of bacterial gene expression occurring in human tissues during a natural infection. GASTROENTEROLOGY 2002;123:1637-1648

Listeria monocytogenes is a food-borne bacterial pathogen that is able to grow at refrigeration temperatures. To investigate microbial gene expression associated with cold acclimation, we used a differential cDNA cloning procedure known as selective capture of transcribed sequences (SCOTS) to identify bacterial RNAs that were expressed at elevated levels in bacteria grown at 10°C compared to those grown at 37°C. A total of 24 different cDNA clones corresponding to open reading frames in the L. monocytogenes strain EGD-e genome were obtained by SCOTS. These included cDNAs for L. monocytogenes genes involved in previously described cold-adaptive responses ( flaA and flp ), regulatory adaptive responses ( rpoN , lhkA , yycJ , bglG , adaB , and psr ), general microbial stress responses ( groEL , clpP , clpB , flp , and trxB ), amino acid metabolism ( hisJ , trpG , cysS , and aroA ), cell surface alterations ( fbp , psr , and flaA ), and degradative metabolism ( eutB , celD , and mleA ). Four additional cDNAs were obtained corresponding to genes potentially unique to L. monocytogenes and showing no significant similarity to any other previously described genes. Northern blot analyses confirmed increased steady-state levels of RNA for all members of a subset of genes examined during growth at a low temperature. These results indicated that L. monocytogenes acclimation to growth at 10°C likely involves amino acid starvation, oxidative stress, aberrant protein synthesis, cell surface remodeling, alterations in degradative metabolism, and induction of global regulatory responses.

Background In an effort to improve quality and reduce costs, payments are being increasingly tied to value through alternative payment models, such as episode-based payments. The objective of this study was to better understand the pattern and variation in outcomes among Medicare beneficiaries receiving lower extremity joint arthroplasty over 90-day episodes of care. Methods Observed rates of mortality, complications, and readmissions were calculated over 90-day episodes of care among Medicare fee-for-service beneficiaries who received elective knee arthroplasty and elective or nonelective hip arthroplasty procedures in 2013-2014 (N = 640,021). Post–acute care utilization of skilled nursing and inpatient rehabilitation facilities was collected from Medicare files. Results Mortality rates over 90 days were 0.4% (knee arthroplasty), 0.5% (elective hip arthroplasty), and 13.4% (nonelective hip arthroplasty). Complication rates were 2.1% (knee arthroplasty), 3.0% (elective hip arthroplasty), and 8.5% (nonelective hip arthroplasty). Inpatient rehabilitation facility utilization rates were 6.0% (knee arthroplasty), 6.7% (elective hip arthroplasty), and 23.5% (nonelective hip arthroplasty). Skilled nursing facility utilization rates were 33.9% (knee arthroplasty), 33.4% (elective hip arthroplasty), and 72.1% (nonelective hip arthroplasty). Readmission rates were 6.3% (knee arthroplasty), 7.0% (elective hip arthroplasty), and 19.2% (nonelective hip arthroplasty). Patients' age and clinical characteristics yielded consistent patterns across all outcomes. Conclusion Outcomes in our national cohort of Medicare beneficiaries receiving lower extremity joint arthroplasties varied across procedure types and patient characteristics. Future research examining trends in access to care, resource use, and care quality over bundled episodes will be important for addressing the challenges of value-based payment reform.

The objective of this study was to investigate the associations between handgrip strength and both physical function and mortality in older Mexican Americans. Data are from a ten-year prospective cohort study of 1,368 Mexican-Americans aged 75 and older from the Hispanic Established Population for the Epidemiologic Study of the Elderly. Measures included socio-demographic variables, hand grip strength, the Short Physical Performance Battery (SPPB), medical conditions, cognitive function, depression, body mass index, and mortality. Baseline hand grip strength means for women and men were 17.6 Kg (4.8) and 27.9 Kg (7.2), respectively. Means for the SPPB were 6.7 (2.9) for women and 7.5 (2.9) for men. At follow-up, 584 participants were confirmed dead. Using general linear mixed models, we found that women in the second and third lowest handgrip strength quartiles had greater SPPB declines over time (b= -0.13; standard error=0.06, p=0.02 and b= -0.14, standard error=0.05, p=0.01, respectively) compared to participants in the highest quartile. This association remained statistically significant after controlling for all covariates. No significant association was found between hand grip strength quartiles and changes in SPPB scores in men. In women and men in the lowest hand grip strength quartile, the hazard ratio of death controlling for all covariates was 1.66 (95% CI = 1.17–2.37) and 2.09 (95% CI = 1.42–3.07), respectively, compared with those in the highest hand strength quartile. Hand grip strength is a strong predictor of long-term decline in physical function and mortality in older Mexican Americans, after controlling for other relevant risk factors.

Objective To identify determinants for the use of a walking device in persons with Parkinson's disease (PD). Design Cross-sectional study of participants with PD. Setting Laboratory. Participants Persons with PD (N=85; 60 men) were studied. Their mean age was 69.4±8.9 years. The average time since diagnosis was 7.9±5.3 years. Interventions Not applicable. Main Outcome Measures Age, sex, disease duration, disease severity, and motor impairment were recorded. Participants were asked whether they usually used any walking device (eg, cane or walker) and were categorized as either an "independent walker" or a "device walker." Clinical balance measures including functional reach, turn duration, 5-meter timed Up and Go (5m-TUG) test, and Activities-specific Balance Confidence (ABC) scale were investigated for their contribution to the prediction of walking with a device. Results Thirty-one participants (36.5%) reported that they usually used a walking device. Classification and regression tree analysis determined that the 5m-TUG test and the ABC scale were important factors in differentiating participants who used a walking device from those who did not. Critical thresholds included 13 seconds for the 5m-TUG test and a score of 75 for the ABC scale in determining device walking. Using only these 2 determinants, the classification and regression tree model correctly classified 81% of the patients as either independent or needing a walking device. Conclusion The 5m-TUG test and the ABC scale may be useful in clinical assessments of the need for a walking device in persons with PD.

The purpose of this study was to explore trajectories of recovery in patients with lower extremity joint replacements receiving post-acute rehabilitation. A retrospective cohort design was used to examine data from the Uniform Data System for Medical Rehabilitation (UDSMR®) for 7434 patients with total knee replacement (TKR) and 4765 patients with total hip replacement (THR) who received rehabilitation from 2008 to 2010. Functional Independence Measure (FIM)™ instrument ratings were obtained at admission, discharge, and 80–180 days after discharge. Random coefficient regression analyses using linear mixed models were used to estimate mean ratings for items within the four motor subscales (self-care, sphincter control, transfers, and locomotion) and the cognitive domain of the FIM instrument. Mean improvements at discharge for motor items ranged from 1.16 (95% confidence interval [CI]: 1.14, 1.19) to 2.69 (95% CI: 2.66, 2.71) points for sphincter control and locomotion, respectively. At follow-up mean motor improvements ranged from 2.17 (95% CI: 2.15, 2.20) to 4.06 (95% CI: 4.03, 4.06) points for sphincter control and locomotion, respectively. FIM cognition yielded smaller improvements: discharge = 0.47 (95% CI: 0.46, 0.48); follow-up = 0.83 (95% CI: 0.81, 0.84). Persons who were younger, female, non-Hispanic white, unmarried, with fewer comorbid conditions, and who received a TKR demonstrated slightly higher functional motor ratings. Overall, patients with unilateral knee or hip replacement experienced substantial improvement in motor functioning both during and up to six months following inpatient rehabilitation.

Purpose: To assess the role of chemoradiation as a primary treatment for vulvar carcinoma. Methods and Materials: Between December 1989 and August 1997, there were 14 patients with the diagnosis of squamous cell carcinoma of the vulva. Two patients were excluded from this study because of advanced stage at presentation. Key information about the remaining 12 patients was extracted from their charts. All patients had biopsy prior to treatment, and were treated with chemoradiation. Radiation was administered to the vulva only. Surgical biopsies from the vulva and inguinal nodal dissection were done 4–6 weeks after radiation treatment. All patients were followed for evaluation of response and clinical detection of recurrence. The period of follow-up ranged from 8 to 125 months. Mean follow-up period was 41 months. Results: All 12 patients showed complete response to the treatment. Only 1 patient (8.3%) developed local recurrence at 3 months posttreatment. Another patient (8.3%) developed nodal recurrence at 30 months posttreatment. Both patients were salvaged by surgical treatment and remained disease free. The actuarial 5-year disease-free survival was 43%. The actuarial 3-year disease-free survival was 84%. The majority of patients developed mild-to-moderate complications due to chemoradiation. These were well tolerated and responded to medical treatment. None of the patients developed late complications to chemoradiation treatment. Conclusions: Chemoradiation is an effective primary treatment for vulvar carcinoma as shown by these successfully managed cases.

The in vitro function of the coliphage lambda tR1 Rho-dependent terminator is governed primarily by a tripartite upstream sequence element designated rut. To determine the contribution of the different components of the rut site to terminator function in the normal context of coupled translation of the nascent cro message, tR1 variants lacking different rut site sequences were tested for terminator function in vivo. Intact rutA and rutB sequences were both necessary for efficient termination. However, deletion of the upstream rutA was far more detrimental than deletion of rutB. The intervening boxB, which encodes a short RNA stem and loop, could be deleted without reducing termination or detectably altering Rho's interaction with the corresponding cro transcript. The relative importance of these sequence elements was also the same in a minimal in vitro termination assay system. Rut sequences are therefore essential for terminator function in vivo and rutA contributes substantially more to tR1 function than does rutB. The relative contribution of these elements can be ascribed to differences in Rho's binding affinity for the encoded transcripts. If other cellular factors also bind the rut element RNA, they do not alter the relative contribution of its two regions to Rho-dependent transcription termination in vivo.

Objective To assess the utility of functional status in classifying patients by discharge setting after inpatient rehabilitation for hip fracture. Design Retrospective cohort study. Setting A total of 1257 inpatient rehabilitation facilities in the United States. Patients Medicare beneficiaries (N = 117,168) receiving inpatient rehabilitation for hip fracture from 2007 to 2009. Methods Receiver operating characteristic curve analyses to assess the overall discriminatory ability of functional status scores (Functional Independence Measure [FIM] total, FIM cognition, and FIM motor) and to identify the functioning threshold that best differentiates patients by discharge setting. Main Outcome Measurements Discharge setting (community versus institutional). Results Approximately 68% of patients were discharged to the community after inpatient rehabilitation for hip fracture. Receiver operating characteristic curve analyses indicate that discharge FIM motor ratings (area under the curve: 0.84) alone are as effective as a multivariable model (area under the curve: 0.85), including sociodemographic and clinical factors, in discriminating patients discharged to the community from those discharged to an institution. A discharge FIM motor rating of 58 yielded the best balance in sensitivity and specificity for classifying patients by discharge setting. Conclusions Discharge FIM motor ratings demonstrated good discriminatory ability for classifying discharge setting. An FIM motor rating of 58 may serve as a clinical tool to guide treatment plans and/or as additional information in complex discharge planning decisions for patients with hip fracture.

Breath testing has enormous potential in the medical diagnostic field. The underlying complexity and perceived availability of adequate specimens, combined with a lack of knowledge of the metabolic pathways that give rise to compounds that are sources of analytes detectable in breath, has greatly slowed development. These real obstacles have recently been largely overcome in the use of breath testing to identify patients with cystic fibrosis associated Pseudomonas aeruginosa infection and tuberculosis. This review summarizes progress made in the characterization of microbial volatiles produced by major lower respiratory tract bacterial pathogens, and their potential use as diagnostic markers in patient breath testing.

In this study, we explored the transcriptional response and the morphological changes occurring in porcine mesenteric lymph-nodes (MLN) along a time course of 1, 2 and 6 days post infection (dpi) with Salmonella Typhimurium. Additionally, we analysed the expression of some Salmonella effectors in tissue to complete our view of the processes triggered in these organs upon infection. The results indicate that besides dampening apoptosis, swine take advantage of the flagellin and prgJ expression by Salmonella Typhimuriun to induce pyroptosis in MLN, preventing bacterial dissemination. Furthermore, cross-presentation of Salmonella antigens was inferred as a mechanism that results in a rapid clearance of pathogen by cytotoxic T cells. In summary, although the Salmonella Typhimurium strain employed in this study was able to express some of its major virulence effectors in porcine MLN, a combination of early innate and adaptive immunity mechanisms might overcome virulence strategies employed by the pathogen, enabling the host to protect itself against bacterial spread beyond gut-associated lymph-nodes. Interestingly, we deduced that clathrin-mediated endocytosis could contribute to mechanisms of pathogen virulence and/or host defence in MLN of Salmonella infected swine. Taken together, our results are useful for a better understanding of the critical protective mechanisms against Salmonella that occur in porcine MLN to prevent the spread of infection beyond the intestine.

Background Little is known about the effect of provider continuity prior to the diagnosis of advanced lung cancer and end-of-life care. Methods Retrospective analysis of 69,247 Medicare beneficiaries aged 67 years or older diagnosed with Stage IIIB or IV lung cancer between January 1, 1993 and December 31, 2005 who died within two years of diagnosis. We examined visit patterns to a primary care physician (PCP) and/or any provider one year prior to the diagnosis of advanced lung cancer as measures of continuity of care. Outcome measures were hospitalization, ICU use and chemotherapy use during the last month of life, and hospice use during the last week of life. Results Seeing a PCP or any provider in the year prior to the diagnosis of advanced lung cancer increased the likelihood of hospitalization, ICU care, chemotherapy and hospice use during the end of life. Patients with 1–3, 4–7 or >7 visits to their PCP in the year prior to the diagnosis of lung cancer had 1.0 (reference), 1.08 (95% CI; 1.04–1.13), and 1.14 (95% CI; 1.08–1.19) odds of hospitalization during the last month of life, respectively. Odds of hospice use during the last week of life were higher in patients with visits to multiple PCPs (OR 1.10: 95% CI; 1.06–1.15) compared to those whose visits were all to the same PCP. Conclusion Provider continuity in the year prior to the diagnosis of advanced lung cancer was not associated with lower use of aggressive care during end of life. Our study did not have information on patient preferences and result should be interpreted accordingly.

The twin-arginine translocation (Tat) pathway is one of two general protein transport systems found in the prokaryotic cytoplasmic membrane and is conserved in the thylakoid membrane of plant chloroplasts. The defining, and highly unusual, property of the Tat pathway is that it transports folded proteins, a task that must be achieved without allowing appreciable ion leakage across the membrane. The integral membrane TatC protein is the central component of the Tat pathway. TatC captures substrate proteins by binding their signal peptides. TatC then recruits TatA family proteins to form the active translocation complex. Here we report the crystal structure of TatC from the hyperthermophilic bacterium Aquifex aeolicus. This structure provides a molecular description of the core of the Tat translocation system and a framework for understanding the unique Tat transport mechanism.

OBJECTIVE: : To extend the representativeness of the Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) for individuals 16 years and older, admitted for acute, inpatient rehabilitation in the United States with a primary diagnosis of traumatic brain injury (TBI) analyses completed by Corrigan and colleagues by comparing this data set to national data for patients admitted to inpatient rehabilitation with identical inclusion criteria that included 3 additional years of data and 2 new demographic variables. DESIGN: : Secondary analysis of existing data sets and extension of previously published analyses. SETTING: : Acute inpatient rehabilitation facilities. PARTICIPANTS: : Patients 16 years and older with a primary rehabilitation diagnosis of TBI; the US TBI Rehabilitation population, n = 156 447; and the TBIMS-NDB population, n = 7373. INTERVENTIONS: : None. MAIN OUTCOME MEASURES: : Demographics, functional status, and length of stay in hospital. RESULTS: : The TBIMS-NDB was largely representative of patients 16 years and older, admitted for rehabilitation in the United States with a primary diagnosis of TBI on or after October 1, 2001, and discharged as of December 31, 2010. The results of the extended analyses were similar to those reported by Corrigan and colleagues. Age accounted for the largest difference between the samples, with the TBIMS-NDB including a smaller proportion of patients 65 years and older than all those admitted for rehabilitation with a primary diagnosis of TBI in the United States. After partitioning each data set at age 65, most distributional differences found between samples were markedly reduced; however, differences in the preinjury vocational status of the employed and rehabilitation lengths of stay between 1 and 9 days remained robust. The subsamples of patients 64 years and younger were found to differ only slightly on all remaining variables, whereas those 65 years and older were found to have meaningful differences in insurance type and age distribution. CONCLUSIONS: : These results reconfirm that the TBIMS-NDB is largely representative of patients with TBI receiving inpatient rehabilitation in the United States. Differences between the 2 data sets were found to be stable across the 3 additional years of data, and new differences were limited to those involving newly introduced variables. To use these data for population-based research, it is strongly recommended that statistical adjustment be conducted to account for the lower percentage of patients older than 65 years, inpatient rehabilitation stays less than 10 days, and preinjury vocational status in the TBIMS-NDB. Language: en

The objectives of this study were: to identify the factors that are associated with prescription of wheeled mobility devices for older adults, and to determine the effect that living setting has on the types of devices that older adults receive. Retrospective medical chart review at the Center for Assistive Technology on 337 older individuals. These individuals were aged >60 years, and each of them received a new wheeled mobility device from the center during 2007 or 2008. Data were analyzed in three tiers: tier 1 (manual versus powered mobility devices); tier 2 (motorized scooters versus power wheelchairs); and tier 3 (customized versus standard power wheelchairs). For tier 1, the factor associated with higher odds for receipt of manual wheelchairs versus powered were: cognitive limitations (OR = .03). For tier 2, diagnosis of cardio-vascular and pulmonary conditions were associated with prescription of motorized scooters (OR = 3.9). For tier 3, neurological conditions (OR = 3.1), male gender (OR = .37), institutional living (OR = .23), and lower age (OR = .96) were associated with receipt of customized power wheelchairs. This study objectively describes factors associated with prescription of wheeled mobility for older adults. This information can aid in development of guidelines and improving standards of practice for prescription of wheelchairs for older adults.

Background: Readmission is an important quality indicator following acute care hospitalization. We examined factors associated with hospital readmission in persons with stroke following postacute inpatient rehabilitation. Methods: Prospective cohort study including 674 persons with stroke who received rehabilitation at 11 facilities located in eight states and the District of Columbia. Measures included hospital readmission within 3 months of discharge, sociodemographic characteristics, length of stay, primary payment source, comorbidities, stroke type, standardized assessments of motor and cognitive function, depressive symptoms, and social support. Results: Mean age was 71.5 years (SD = 10.5). Twenty-five percent of patients reported high depressive symptoms. Overall, 18% (n = 122) of the sample was rehospitalized. Univariate analyses showed that people who were rehospitalized were more likely (p < .05) to be non-Hispanic white, married, demonstrate less functional independence at discharge, experience longer lengths of stay in rehabilitation, and report more depressive symptoms and lower social support. In the fully adjusted multivariable hierarchical generalized linear model, motor functional status (OR = 0.98, 95% CI 0.96-0.99), depressive symptoms (OR = 1.80, 95% CI 1.06-3.05), and social support (OR = 2.28, 95% CI 1.29-4.03) remained statistically significant. In addition, a minority-by-depressive symptoms interaction term also reached statistical significance. Conclusion: Functional status, depressive symptoms, and social support were important predictors of hospital readmission. These variables are not included in most administrative data sets. Future research to develop useful risk-adjustment models for rehospitalization following postacute inpatient rehabilitation services should include large diverse samples and explore practical sources for additional meaningful information.

To identify factors contributing to the ability of tubercle bacilli to grow in the lung during active infection, we analyzed RNA expression patterns in bacteria present in patient sputum. Prominent among bacterial transcripts identified were those encoding secreted peptides of the Esat-6 subfamily that includes EsxK and EsxL (Rv1197 and Rv1198). H37Rv esxKL and esxJI transcripts were differentially expressed under different growth conditions, and disruption of these genes altered growth phase kinetics in typical laboratory batch broth cultures. These growth defects, including the reduced intracellular growth of an ΔesxKL mutant in primary human macrophages, were reversed by either low multiplicity co-infection or co-culture with wild-type bacteria, demonstrating the ability of the secreted factors to rescue isogenic mutants. Complementing either only esxL or esxI alone (Rv1198 or Rv1037c) also reduced observed growth defects, indicating these genes encode factors capable of contributing to growth. Our studies indicate that the M. tuberculosis Mtb9.9 family secreted factors EsxL and EsxI can act in trans to modulate growth of intracellular bacteria, and are highly expressed during active human lung infection. EsxL (Rv1197 and Rv1198). The H37Rv genome contains 4 additional and nearly identical pairs of co-linear open reading frames designated esx JI, esx MN, esx PO, and esxWV. These ORFs show little sequence similarity to esxBA (Cfp10-Esat-6), other than encoding 2 short ~100 residue peptides with the 5’ ORF encoding a variant carboxyl-terminal 'QILSS' motif and the 3’ encoding the Mtb9.9 family of secreted T-cell antigens. All contain a central ‘WXG100’ esx family structural motif, and are thought to encode effectors of an uncharacterized ESX-5 transport system. esxKL and esxJI transcripts were differentially expressed under different growth conditions, and disruption of these genes altered different growth phase kinetics in typical laboratory batch broth cultures.

Background Salmonella enterica serotype Typhi is the cause of typhoid fever. It is a human-restricted pathogen, and few data exist on S. Typhi gene expression in humans. Methodology/Principal Findings We applied an RNA capture and amplification technique, Selective Capture of Transcribed Sequences (SCOTS), and microarray hybridization to identify S. Typhi transcripts expressed in the blood of five humans infected with S. Typhi in Bangladesh. In total, we detected the expression of mRNAs for 2,046 S. Typhi genes (44% of the S. Typhi genome) in human blood; expression of 912 genes was detected in all 5 patients, and expression of 1,100 genes was detected in 4 or more patients. Identified transcripts were associated with the virulence-associated PhoP regulon, Salmonella pathogenicity islands, the use of alternative carbon and energy sources, synthesis and transport of iron, thiamine, and biotin, and resistance to antimicrobial peptides and oxidative stress. The most highly represented group were genes currently annotated as encoding proteins designated as hypothetical, unknown, or unclassified. Of the 2,046 detected transcripts, 1,320 (29% of the S. Typhi genome) had significantly different levels of detection in human blood compared to in vitro cultures; detection of 141 transcripts was significantly different in all 5 patients, and detection of 331 transcripts varied in at least 4 patients. These mRNAs encode proteins of unknown function, those involved in energy metabolism, transport and binding, cell envelope, cellular processes, and pathogenesis. We confirmed increased expression of a subset of identified mRNAs by quantitative-PCR. Conclusions/Significance We report the first characterization of bacterial transcriptional profiles in the blood of patients with typhoid fever. S. Typhi is an important global pathogen whose restricted host range has greatly inhibited laboratory studies. Our results suggest that S. Typhi uses a largely uncharacterized genetic repertoire to survive within cells and utilize alternate energy sources during infection., Author Summary Salmonella enterica serotype Typhi is the cause of typhoid fever and infects over 21 million cases and causes 200,000 deaths each year. S. Typhi only infects humans and this has greatly limited studies of S. Typhi pathogenesis. To study bacterial gene expression in human hosts, we used Selective Capture of Transcribed Sequences (SCOTS) and array hybridization to identify S. Typhi mRNAs expressed in the blood of 5 patients with S. Typhi infection. In total, we detected the expression of 2,046 S. Typhi genes (44% of the S. Typhi genome) in human blood; of these, 1,320 (29% of the S. Typhi genome) had significantly different levels of detection in human blood compared to in vitro cultures. Our results provide insight into S. Typhi pathogenesis, identifying both previously described and novel interactions occurring between host and microbe during the natural course of human infection. Further study of these genes, especially those of unknown function, may further our understanding of S. Typhi pathogenesis and aid in vaccine, diagnostic, and/or drug target development.

OBJECTIVE:: To determine whether the Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) is representative of individuals aged 16 years and older admitted for acute, inpatient rehabilitation in the United States with a primary diagnosis of traumatic brain injury (TBI). DESIGN:: Secondary analysis of existing data sets. SETTING:: Acute inpatient rehabilitation facilities. PARTICIPANTS:: Patients aged 16 years and older with a primary rehabilitation diagnosis of TBI. MAIN OUTCOME MEASURES:: Demographic characteristics, functional status, and hospital length of stay. RESULTS:: Patients included in the TBIMS-NDB from October 2001 through December 2007 were largely representative of all individuals 16 years and older admitted for rehabilitation in the United States with a primary diagnosis of TBI. The major difference in distribution was age-the TBIMS-NDB cohort did not include as large a proportion of patients older than 65 years as were admitted for rehabilitation with a primary diagnosis of TBI in the United States. Distributional differences for age-related characteristics were observed; however, groups of patients partitioned at aged 65 years differed minimally, especially within the younger than 65 years subset. Regardless of age, the proportion of patients with a rehabilitation stay of 1 to 9 days was larger nationwide. Nationwide admissions showed an age distribution similar to patients discharged alive from acute care with moderate, severe or penetrating TBI. The proportion of patients aged 70 years and older admitted for TBI rehabilitation in the United States increased every year, a trend that was not evident in the general population, TBIMS-NDB or among TBI patients in acute care. CONCLUSIONS:: These results provide substantial empirical evidence that the TBIMS-NDB is representative of patients receiving inpatient rehabilitation for TBI in the United States. Researchers utilizing the TBIMS-NDB may want to adjust statistically for the lower percentage of patients older than 65 years or those with stays less than 10 days. Language: en

To examine the association between self-reported physician-diagnosed arthritis and health-related quality of life among older Mexican Americans.Cross-sectional study involving population-based survey.Hispanic Established Population for the Epidemiologic Study of the Elderly (EPESE) survey conducted in Texas, Arizona, New Mexico, Colorado, and California.839 non-institutionalized Mexican American older adults (or = 75 years) participating in Hispanic EPESE.Self-reported physician-diagnosed arthritis; sociodemographic variables; medical conditions; body mass index; and the physical and mental composite scales from the Medical Outcomes Study Short Form 36 Health Survey (SF-36).518 (62%) of the subjects reported physician-diagnosed arthritis. Participants with arthritis had significantly lower scores on the physical composite scale (PCS) (mean = 35.3, SD = 11.3) and the mental composite scale (MCS) (mean = 53.5, SD = 10.8) of the SF-36 compared to persons without arthritis (PCS mean = 42.9, SD = 10.9; MCS mean = 57.0, SD = 8.8). Multiple regression showed that arthritis was associated with decreased PCS and MCS (model estimates of -5.74 [SE = .83]; and -3.16 [SE = .64]), respectively, after controlling for sociodemographic and clinical covariates.Arthritis is a highly prevalent medical condition in Mexican American older adults. Our findings suggest that deficits in both physical health and mental function contribute to reduced quality-of-life in this population.

Fisher SR, Galloway RV, Kuo Y-F, Graham JE, Ottenbacher KJ, Ostir GV, Goodwin JS. Pilot study examining the association between ambulatory activity and falls among hospitalized older adults. Objective To examine the ambulatory activity of older patients who had a documented fall during hospitalization for acute illness. Design A retrospective case-control design was used in a pilot study of patients (n=10; ≥65y) who had a documented fall during their hospital stay and matched controls (n=25) who did not fall. Setting Acute care medical/surgical unit. Participants Men and women 65 years and older who wore a step activity monitor while hospitalized. Interventions Not applicable. Main Outcome Measures Fall incidents during the hospital stay were documented by the nurse in a standardized patient safety event report in accordance with hospital policy. The number of steps per 24-hour interval, time spent walking, and total number of activity episodes were determined for patients and controls. Results On average ± SD, patients who fell took 480.3±432.2 steps per hospital day, spent 53.8±36.9 minutes walking, and engaged in 25.8±16.9 episodes of activity. Mean daily steps, time spent walking, and number of activity episodes for patients who did not fall were 680.1±876.0, 50.1±58.6, and 21.6±23.8, respectively. Logistic regression results indicated no association between the fall outcome and mean daily steps (odds ratio=.95; 95% confidence interval, 0.84–1.06). Conclusions Ambulatory activity among patients who fell varied widely. Mean daily steps, time spent walking, and number of episodes of activity were comparable with matched controls who did not fall. Patient falls were more likely to be associated with cognitive and hospital environmental factors than actual amount of walking.

Depression is often associated with illness or injury requiring acute hospitalization, particularly in older adults. We sought to determine patterns of change in depressive symptoms in older adults from hospitalization to 3 months post discharge and to examine factors associated with depressive symptoms 3 months after discharge. The study included 197 patients aged 65 years or older hospitalized with an acute medical illness. Sociodemographic and clinical measures, including depressive symptoms using the Center for Epidemiologic Study—Depression (CES-D) scale, were collected during the inpatient stay and at 3 months post discharge. Mean age was 75.3 ± 7.5 (±S.D.) years, 59% of the participants were female, 61% unmarried, and 72% had a high school education or more. High depressive symptoms (i.e., CES-D ≥ 16) were reported in 37% at admission. Of the 8% depressed at follow-up, 81% were also depressed at admission; 19% were new cases of depression. Depressive symptoms 3 months post-hospitalization were significantly associated with follow-up daily living skills (p = 0.001) and social support (p < 0.0001). Patients with persistent depressive symptoms make up the majority of post-hospitalization depression cases. Post-hospitalization social support and daily living skills appear to be important in the management of follow-up depressive symptoms.

Recent advances in DNA sequencing have greatly accelerated our ability to obtain the raw information needed to recognize both known and potential novel modular microbial genomic capacity for nitrogen metabolism. With PCR-based approaches to quantifying microbial mRNA expression now mainstream in most laboratories, researchers can now more efficiently propose and test hypotheses on the contributions of individual microbes to the biological accessibility of nitrogen upon which all other life depends. We review known microbial roles in these key nitrogen transformations, and describe the necessary steps in carrying out relevant gene expression studies. An example experimental design is then provided characterizing Nitrosococcus oceani mRNA expression in cultures responding to ammonia. The approach described, that of assessing microbial genome inventory and testing putative modular gene expression by mRNA quantification, is likely to remain an important tool in understanding individual microbial contributions within microbial community activities that maintain the Earth's nitrogen balance.

There are no therapeutic guidelines regarding ambulation for older adults hospitalized for acute illness.1 The importance of early ambulation to recovery in other patient populations is well established.2,3 For example, time to ambulation after hip fracture surgery is a predictor of complications such as prolonged length of stay (LOS).4 In the present study, we examined the association between ambulation and LOS in geriatric patients admitted for acute illnesses. We hypothesized that increase in ambulation within the 48 hours after admission would predict LOS after adjusting for risk factors.

To provide benchmarking information from a large national sample of patients receiving inpatient rehabilitation after lower limb joint replacement.Secondary data analysis from 893 medical rehabilitation facilities located in the United States that contributed information to the Uniform Data System for Medical Rehabilitation from January 2000 through December 2007. Variables analyzed included demographic information (age, sex, marital status, race/ethnicity, prehospital living setting, discharge setting), hospitalization information (length of stay, program interruptions, payer, onset date, rehabilitation impairment group, International Classification of Diseases, 9th revision codes for admitting diagnosis, comorbidities), and functional status information (FIM instrument ["FIM"] ratings at admission and discharge, FIM efficiency, FIM gain).Descriptive statistics from 705,345 patients showed an overall mean length of stay of 8.9 (±4.7) days. FIM total admission and discharge ratings declined during the 8-yr study period. Mean admission ratings decreased from 83.5 (±11.3) to 73.2 (±12.9). Mean discharge ratings decreased from 108.4 (±11.0) to 101.7 (±12.9). Conversely, mean FIM change increased from 24.9 (±9.2) to 28.6 (±12.2). The percent of persons discharged to the community decreased from 94.5% to 91.9%. All results are likely to be influenced by various policy changes affecting classification or documentation processes or both.National rehabilitation data from persons with lower limb joint replacement in 2000-2007 indicate that inpatient rehabilitation lengths of stay have remained relatively stable and that patients are experiencing improvements in functional independence during their stay. In addition, more than 9 of 10 patients are discharged to community settings after inpatient rehabilitation.

Escherichia coli FtsK is a powerful, fast, double-stranded DNA translocase, which can strip proteins from DNA. FtsK acts in the late stages of chromosome segregation by facilitating sister chromosome unlinking at the division septum. KOPS-guided DNA translocation directs FtsK towards dif, located within the replication terminus region, ter, where FtsK activates XerCD site-specific recombination. Here we show that FtsK translocation stops specifically at XerCD-dif, thereby preventing removal of XerCD from dif and allowing activation of chromosome unlinking by recombination. Stoppage of translocation at XerCD-dif is accompanied by a reduction in FtsK ATPase and is not associated with FtsK dissociation from DNA. Specific stoppage at recombinase-DNA complexes does not require the FtsKgamma regulatory subdomain, which interacts with XerD, and is not dependent on either recombinase-mediated DNA cleavage activity, or the formation of synaptic complexes.

To examine the association between frailty and 10-year mortality among older men and women of Mexican American origin.Data were collected from 1995-1996 through 2004-2005 among community-dwelling Mexican Americans agedor=65 years as part of the Hispanic Established Population for the Epidemiologic Study of the Elderly (HEPESE). A standardized frailty measure based on weight loss, exhaustion, grip strength, walking speed, and physical activity was computed. Data were collected on sociodemographics and health characteristics, comorbidities, and performance-based functional measure.The sample was 59% female, and mean baseline age was 74.5 years of (SD 6.06) at baseline. Hazard ratios (HR) indicated an increased mortality risk in frail men (HR = 3.04, 95% CI 2.16-4.28) compared with frail women (HR = 1.92, 95% CI 1.39-2.65).Frailty is an independent predictor of mortality among older men and women of Mexican American origin. This association was found to be stronger among men after adjusting for age, marital status, education, body mass index (BMI), health behaviors, and medical conditions.

Background: The older Hispanic population of the United States is growing rapidly. Hispanic older adults have relatively high-risk profiles for increased morbidity and disability, yet little is known about how the construct of frailty is related to health trajectories in this population. Objective: The purpose of this study was to examine the relationship between frailty and 10-year mortality in older community-dwelling Mexican Americans. Methods: Data were from the Hispanic Established Populations for Epidemiologic Studies of the Elderly and included 1,996 Mexican Americans, aged 65 and older, living in the southwestern US. Primary measures included mortality and a 5-item frailty index comprised of weight loss, exhaustion, walking speed, grip strength, and physical activity. Results: Mean baseline age was 74.5 years (SD 6.1) and 58.5% were women. Baseline frailty assessments yielded the following distribution: 44.9% non-frail, 47.3% pre-frail, and 7.8% frail. Overall, 892 (44.7%) participants died during the 10-year study period. Hazard ratios (HR), adjusted for sociodemographic, health, and medical factors, demonstrated increased odds for mortality in the pre-frail (HR = 1.25, 95% confidence interval, CI95%, 1.07–1.46) and frail (HR = 1.81, CI95% 1.41–2.31) groups compared to the non-frail cohort. Conclusion: The 5-item frailty index differentiated odds of 10-year mortality in older community-dwelling Mexican Americans. This clinical index has the potential to identify older minorities at risk for poor health outcomes and mortality.

Background Previous research on frailty in older adults has focused on morbidity and mortality. The purpose of this study was to elicit the relationship between being non-frail, pre-frail, or frail and health related quality of life in a representative sample of older Mexican Americans surveyed in 2005–2006. Methods Data were from a representative subsample of the Hispanic Established Populations Epidemiologic Studies of the Elderly (EPESE) and included 1008 older adults living in the community (mean (sd) age = 82.3(4.3)). Multiple regression analyses examined the relationship between frailty status and the eight SF-36 health related quality of life subscales and two summary scales. Models also adjusted for the participants' sociodemographic and health status. Results We found that, after adjusting for sociodemographic and health related covariables, being pre-frail or frail was significantly associated (p < 0.001) with lower scores on all physical and cognitive health related quality of life scales than being non-frail. Conclusion When compared to persons who are not frail, older Mexican American individuals identified as frail and pre-frail exhibit significantly lower health related quality of life scores. Future research should assess potential mediating factors in an effort to improve quality of life for frail elders in this population.

Objectives. We examined the prevalence of frailty among Mexican American older adults and explored the correlates associated with becoming frail to determine their affect on disability and morbidity in this population. Methods. We studied the trajectory of frailty over 10 years in 2049 Mexican Americans participating in the Hispanic Established Populations Epidemiologic Studies of the Elderly. We constructed a frailty index based on weight loss, exhaustion, grip strength, walking speed, and physical activity and collected data on sociodemographic and health status, comorbidities, and functional measures of performance. Results. The sample was 58% female, with a mean age of 74.43 years (SD = 6.04) at baseline. Fifty-five percent of participants at baseline and 75% of the surviving sample at follow-up (n = 777) were classified as prefrail or frail. Of persons identified as frail at baseline, 84% died by the end of follow-up. Baseline age, diabetes, arthritis, smoking status, body mass index, cognition, negative affect, and number of comorbid conditions were predictors of frailty at follow-up (R2 = 0.29; P < .05). Conclusions. Further research into ways to reduce the number of Mexican American older adults who become frail and disabled and therefore lose their independence is needed. Future studies should continue to examine the trajectory of frailty as a dynamic process that includes psychosocial and cognitive components.

Background. Hip fracture results in severe and often permanent reductions in overall health and quality of life for many older adults. As the U.S. population grows older and more diverse, there is an increasing need to assess and improve outcomes across racial/ethnic cohorts of older hip fracture patients. Methods. We examined data from 42,479 patients receiving inpatient rehabilitation for hip fracture who were discharged in 2003 from 825 facilities across the United States. Outcomes of interest included length of stay, discharge setting, and functional status at discharge and 3- to 6-month follow-up. Results. Mean age was 80.2 (standard deviation [SD] ¼ 8.0) years. A majority of the sample was non-Hispanic white (91%), followed by non-Hispanic black (4%), Hispanic (4%), and Asian (1%). After controlling for sociodemographic factors and case severity, significant (p , .05) differences between the non-Hispanic white and minority groups were observed for predicted lengths of stay in days (Asian: 1.1; 95% confidence interval [CI], 0.5–1.7; non-Hispanic black: 0.8; 95% CI, 0.6–1.1), odds of home discharge (Asian: 2.1; 95% CI, 1.6–2.8; non-Hispanic black: 2.0; 95% CI, 1.8–2.3; Hispanic: 1.9; 95% CI, 1.6–2.2), lower discharge Functional Independence Measure (FIM) ratings (non-Hispanic black: 3.6; 95% CI, 3.0–4.2; Hispanic: 1.6; 95% CI, 0.9–2.2 points lower), and lower follow-up FIM ratings (Hispanic: 4.4; 95% CI, 2.8–5.9). Conclusions. Race/ethnicity differences in outcomes were present in a national sample of hip fracture patients following inpatient rehabilitation. Recognizing these differences is the first step toward identifying and understanding potential mechanisms underlying the relationship between race/ethnicity and outcomes. These mechanisms may then be addressed to improve hip fracture care for all patients.

To examine gender and ethnic differences in functional status and living setting for patients after hip arthroplasty.Retrospective cohort study of 69,793 patients receiving inpatient medical rehabilitation after hip arthroplasty included in the Uniform Data System for Medical Rehabilitation database for the period of 2002-2003. Primary measures included functional status as assessed by the FIM instrument and discharge living setting (home vs. not home). The sample included non-Hispanic white, non-Hispanic black, Hispanic, and Asian patients.Multivariate regression models showed the greatest FIM instrument change scores from admission to discharge among non-Hispanic whites (mean [SE]: 23.42 [0.18]) and among women (mean [SE]: 22.79 [0.23]). Asians had the lowest mean change scores (mean [SE]: 22.00 [0.53]). Estimates from multivariate logistic models showed that being of nonwhite ethnicity was associated with higher odds of home discharge (black: OR [CI]: 1.23, CI 95% = 1.07, 1.41; Hispanic: OR [CI]: 1.51, CI 95% = 1.15-1.99). Compared with women, men had higher odds of home discharge (OR [CI]: 1.08, CI 95% = 1.01, 1.17).The findings suggest that ethnic and gender disparities exist in postacute care outcomes for persons with hip arthroplasty.

To examine the extent to which diabetes codes that increase reimbursement (tier comorbidities) under the prospective payment system are related to length of stay and functional outcomes in stroke rehabilitation.Secondary data analysis.Inpatient rehabilitation facilities (N=864) across the United States.Patients (N=135,097) who received medical rehabilitation for stroke in 2002-2003.None.Length of stay, FIM instrument, and discharge setting. Diabetes status was assigned to 1 of 3 categories: tier (increases reimbursement), nontier (no reimbursement effect), and no diabetes.Mean +/- standard deviation age of the sample was 70.4+/-13.4 years, and 31% had diabetes (6% tier, 25% nontier). Diabetes status by age demonstrated significant (P.05) interaction effects, which lead to the following age-specific findings. In younger stroke patients (60y), tier diabetes was associated with shorter lengths of stay compared with both groups, lower FIM discharge scores compared with both groups, and lower odds of discharge home relative to the no-diabetes group. In older stroke patients (80y), tier diabetes was associated with longer lengths of stay compared with both groups and with higher FIM discharge scores compared with the nontier group.The diabetes-related conditions identified as tier comorbidities under the prospective payment system are significant predictors of stroke rehabilitation outcomes, but these relationships are moderated by patient age.

OBJECTIVE Interest in exploring the positive emotional health of adults has increased. The current study investigated the positive emotion of adults with stroke at discharge from in-patient medical rehabilitation and 3 months post-discharge. DESIGN A longitudinal study in which information was collected during in-patient medical rehabilitation stay and 3 months post-discharge. SUBJECTS The study included 856 persons with stroke aged 55 years or older. RESULTS Mean age for the sample was 72.5 years, 78.7% of subjects were non-Hispanic white and 51.9% were women. Mean length of hospital stay was 20.2 days. More than one-third of patients reported higher positive emotion over the 3-month follow-up, while 29.7% reported lower positive emotion. In addition to discharge positive emotion, 4 factors, including depression, level of education and motor and cognition functional status score, significantly predicted lower depression at 3-month follow-up. CONCLUSION A large percentage of adults reported high positive emotion in the initial months following a stroke. This finding adds to work on stroke recovery and indicates the emotional resilience of adults when faced with a health challenge. Understanding the role of positive emotion in persons living with stroke may provide insight into long-term recovery.

To provide a systematic review and describe how assessments of walking speed are reported in the health care literature.MEDLINE electronic database and bibliographies of select articles were searched for terms describing walking speed and distances walked. The search was limited to English language journals from 1996 to 2006. The initial title search yielded 793 articles. A review of the abstracts reduced the number to 154 articles. Of these, 108 provided sufficient information for inclusion in the current review.Of the 108 studies included in the review 61 were descriptive, 39 intervention and 8 randomized controlled trials. Neurological (n=55) and geriatric (n=27) were the two most frequent participant groups in the studies reviewed. Instruction to walk at a usual or normal speed was reported in 55 of the studies, while 31 studies did not describe speed instructions. A static (standing) start was slightly more common than a dynamic (rolling) start (30 vs 26 studies); however, half of the studies did not describe the starting protocol. Walking 10, 6 and 4 m was the most common distances used, and reported in 37, 20 and 11 studies respectively. Only four studies included information on whether verbal encouragement was given during the walking task.Tests of walking speed have been used in a wide range of populations. However, methodologies and descriptions of walking tests vary widely from study to study, which makes comparison difficult. There is a need to find consensus for a standardized walking test methodology.

To examine recent trends in discharge disposition after hospitalization for hip fracture.Retrospective observational study using data from the 5% random sample of Medicare claims data from 2001 to 2005 that the Centers for Medicare and Medicaid Services makes available for research purposes.Inpatient medical rehabilitation pre- and postimplementation of prospective payment (2001-2005).Forty-four thousand six hundred eighty-four Medicare patients.Postacute discharge setting (home, inpatient rehabilitation, skilled nursing facility, and long-term care nursing home/hospital/hospice).Bivariate analyses showed that discharge from acute care to inpatient rehabilitation increased from 12.2% in 2001 to 23.9% in 2005. The odds of discharge to inpatient medical rehabilitation were 2.26 (95% confidence interval=2.09-2.45) greater in 2005 than in 2001 after adjustment for patient characteristics (age, sex, and race or ethnicity), admitting diagnoses, type of treatment (internal fixation vs arthroplasty), and length of stay.The move from fee for service to prospective payment for postacute services for persons with hip fracture was associated with greater use of inpatient medical rehabilitation. Further research is necessary to confirm the trend in discharge setting and determine whether it is related to changes in reimbursement for postacute care.

Mycobacterium tuberculosismaintains a large genetic capacity necessary for growth in different environments during infection and survival upon aerosol transmission to new hosts. Screening for bacterial RNAs produced in response to host interactions produced candidate lists where we notedproXVWZ, annotated as encoding a putative glycine betaine or proline transporter. As high surface-to-volume ratios make bacterial cells particularly vulnerable to changes in water availability, we investigated the contributions of this transporter to the ability ofM. tuberculosisto colonize macrophages. An H37RvproXVWZmutant was impaired for initial survival and intracellular growth and exhibited reduced growth at elevated medium osmolarity. This defect could be complemented by restoringproXVWZand was attributable to a failure to accumulate the compatible solute glycine betaine. We then demonstrated that ProXVWZ allowsM. tuberculosisto obtain betaine from host macrophages and thereby contributes to early steps in colonizing this niche.

Legionella pneumophila is a ubiquitous organism in the aquatic environment where it is capable of invasion and intracellular proliferation within various protozoan species and is also capable of causing pneumonia in humans. In silico analysis showed that the three sequenced L. pneumophila genomes each contained a common multigene family of 11 ankyrin (ank) genes encoding proteins with approximately 30-35 amino acid tandem Ankyrin repeats that are involved in protein-protein interactions in eukaryotic cells. To examine whether the ank genes are involved in tropism of protozoan hosts, we have constructed isogenic mutants of L. pneumophila in ten of the ank genes. Among the mutants, the DeltaankH and DeltaankJ mutants exhibit significant defects in robust intracellular replication within A. polyphaga, Hartmanella vermiformis and Tetrahymena pyriformis. A similar defect is also exhibited in human macrophages. Most of the ank genes are upregulated by L. pneumophila upon growth transition into the post-exponential phase in vitro and within Acanthamoeba polyphaga, and this upregulation is mediated, at least in part, by RpoS. Single-cell analyses have shown that upon co-infection of the wild-type strain with the ankH or ankJ mutant, the replication defect of the mutant is rescued within communal phagosomes harbouring the wild-type strain, similar to dot/icm mutants. Therefore, at least two of the L. pneumophila eukaryotic-like Ank proteins play a role in intracellular replication of L. pneumophila within amoeba, ciliated protozoa and human macrophages. The Ank proteins may not be involved in host tropism in the aquatic environment. Many of the L. pneumophila eukaryotic-like ank genes are triggered upon growth transition into post-exponential phase in vitro as well as within A. polyphaga. Our data suggest a role for AnkH and AnkJ in modulation of phagosome biogenesis by L. pneumophila independent of evasion of lysosomal fusion and recruitment of the rough endoplasmic reticulum.

PURPOSE The authors examined the effect of blood on susceptibility to experimental endophthalmitis. METHODS Forty rabbits received an injection of 5-25 colony-forming units of Staphylococcus epidermidis into the vitreous of the right eye. Twenty of these same eyes received a subsequent intravitreal injection of 0.2 mL blood while the remaining 20 received an intravitreal injection of 0.2 mL of a salt solution. All eyes were examined daily for signs of endophthalmitis. Vitreous cultures were obtained on day 2 from 30 of the 40 rabbits. Twenty rabbits were assigned for culture and euthanasia at day 5 and those remaining were cultured and killed at day 7. RESULTS In rabbits with blood and bacteria, 10 of 15 (67%) were culture positive at 2 days, compared to 2 of 15 (13%) that received salt solution and bacteria (P < 0.01). At days 5 and 7 there was no statistically significant difference in culture results. However, inflammatory scores were significantly higher at days 3-7 in rabbits with blood compared to those with salt solution (P

Graham JE, Ostir GV, Kuo Y-F, Fisher SR, Ottenbacher KJ. Relationship between test methodology and mean velocity in timed walk tests: a review. Objective To assess the degree to which test methodology affects outcomes in clinical evaluations of walking speed. Data Sources Medline database and reference lists from relevant articles. Study Selection We conducted electronic searches by using various combinations of terms related to clinical evaluations of walking speed. Resultant abstracts were then reviewed, and the methods and results section of promising full-text articles were searched for detailed descriptions of walk-test methodologies and results. Ultimately, articles were limited to the most common participant groups, older adults (aged) and individuals with neurologic conditions (neuro). The final sample included 46 studies. Data Extraction Three aspects of test methodology (pace, starting protocol, distance timed) were extracted for use as independent variables. Group mean age was extracted for use as a covariate. Group mean velocity was extracted for use as the dependent variable. Data were extracted by a single investigator. Data Synthesis Usual and/or comfortable pace was reported nearly twice as often as fast pace in both groups. Static-start protocols were more frequently used in aged studies, whereas dynamic (ie, rolling) starts were more common in neuro studies. Distances of 6 and 10m were most common in aged and neuro studies, respectively. Multivariate analyses (analysis of covariance) showed that only pace was significantly related to the mean velocity in both groups (aged: pace, P P= .21; distance, P= .05; neuro: pace, P= .01; starting protocol, P= .63; distance, P= .49). However, methodology-related differences in the distribution (95% confidence intervals) of performance scores across certain clinical standards were noted within all 3 methodology variables. Conclusions Clinical assessments of walking velocity are not conducted uniformly. Common methodologic factors may influence the clinical interpretation of walk performances. Universal walk-test methodology is warranted to improve intergroup comparisons and the development of useful clinical criteria and consensus norms.

Background The older Hispanic population of the U.S. is growing at a tremendous rate. While ethnic-related risk and complications of diabetes are widely-acknowledged for older Hispanics, less is known about how health related quality of life is affected in this population. Methods Cross-sectional study assessing differences in health related quality of life between older Mexican Americans with and without diabetes. Participants (n = 619) from the Hispanic Established Population for the Epidemiological Study of the Elderly were interviewed in their homes. The primary measure was the Medical Outcomes Study Short Form (SF-36). Results The sample was 59.6% female with a mean age of 78.3 (SD = 5.2) years. 31.2% (n = 193) of the participants were identified with diabetes. Individuals with diabetes had significantly (F = 19.35, p < .001) lower scores on the Physical Composite scale (mean = 37.50, SD = 12.69) of the SF-36 compared to persons without diabetes (mean = 43.04, SD = 12.22). There was no significant difference between persons with and without diabetes on the Mental Composite scale of the SF-36. Conclusion Diabetes was associated with lower health related quality of life in older Mexican Americans. The physical components of health related quality of life uniformly differentiated those with diabetes from those without, whereas mental component scores were equivocal.

We used genome fragment enrichment and bioinformatics to identify several microbial DNA sequences with high potential for use as markers in PCR assays for detection of human fecal contamination in water. Following competitive solution-phase hybridization of total DNA from human and pig fecal samples, 351 plasmid clones were sequenced and were determined to define 289 different genomic DNA regions. These putative human-specific fecal bacterial DNA sequences were then analyzed by dot blot hybridization, which confirmed that 98% were present in the source human fecal microbial community and absent from the original pig fecal DNA extract. Comparative sequence analyses of these sequences suggested that a large number (43.5%) were predicted to encode bacterial secreted or surface-associated proteins. Deoxyoligonucleotide primers capable of annealing to a subset of 26 of the candidate sequences predicted to encode factors involved in interactions with host cells were then used in the PCR and did not amplify markers in DNA from any additional pig fecal specimens. These 26 PCR assays exhibited a range of specificity in tests with 11 other animal sources, with more than half amplifying markers only in specimens from dogs or cats. Four assays were more specific, detecting markers only in specimens from humans, including those from 18 different human populations examined. We then demonstrated the potential utility of these assays by using them to detect human fecal contamination in several impacted watersheds.