The Impact of Health Care Algorithms on Racial and Ethnic Disparities : A Systematic Review.

BACKGROUND: There is increasing concern for the potential impact of health care algorithms on racial and ethnic disparities. PURPOSE: To examine the evidence on how health care algorithms and associated mitigation strategies affect racial and ethnic disparities. DATA SOURCES: Several databases were searched for relevant studies published from 1 January 2011 to 30 September 2023. STUDY SELECTION: Using predefined criteria and dual review, studies were screened and selected to determine: 1) the effect of algorithms on racial and ethnic disparities in health and health care outcomes and 2) the effect of strategies or approaches to mitigate racial and ethnic bias in the development, validation, dissemination, and implementation of algorithms. DATA EXTRACTION: Outcomes of interest (that is, access to health care, quality of care, and health outcomes) were extracted with risk-of-bias assessment using the ROBINS-I (Risk Of Bias In Non-randomised Studies - of Interventions) tool and adapted CARE-CPM (Critical Appraisal for Racial and Ethnic Equity in Clinical Prediction Models) equity extension. DATA SYNTHESIS: Sixty-three studies (51 modeling, 4 retrospective, 2 prospective, 5 prepost studies, and 1 randomized controlled trial) were included. Heterogenous evidence on algorithms was found to: a) reduce disparities (for example, the revised kidney allocation system), b) perpetuate or exacerbate disparities (for example, severity-of-illness scores applied to critical care resource allocation), and/or c) have no statistically significant effect on select outcomes (for example, the HEART Pathway [history, electrocardiogram, age, risk factors, and troponin]). To mitigate disparities, 7 strategies were identified: removing an input variable, replacing a variable, adding race, adding a non-race-based variable, changing the racial and ethnic composition of the population used in model development, creating separate thresholds for subpopulations, and modifying algorithmic analytic techniques. LIMITATION: Results are mostly based on modeling studies and may be highly context-specific. CONCLUSION: Algorithms can mitigate, perpetuate, and exacerbate racial and ethnic disparities, regardless of the explicit use of race and ethnicity, but evidence is heterogeneous. Intentionality and implementation of the algorithm can impact the effect on disparities, and there may be tradeoffs in outcomes. PRIMARY FUNDING SOURCE: Agency for Healthcare Quality and Research.

Evaluating interactions of polygenic risk scores and NAT2 genotypes with tobacco smoking in bladder cancer risk.

Tobacco smoking is the most important risk factor for bladder cancer. Previous studies have identified the N-acetyltransferase (NAT2) gene in association with bladder cancer risk. The NAT2 gene encodes an enzyme that metabolizes aromatic amines, carcinogens commonly found in tobacco smoke. In our study, we evaluated potential interactions of tobacco smoking with NAT2 genotypes and polygenic risk score (PRS) for bladder cancer, using data from the UK Biobank, a large prospective cohort study. We used Cox proportional hazards models to measure the strength of the association. The PRS was derived using genetic risk variants identified by genome-wide association studies for bladder cancer. With an average of 10.1 years of follow-up of 390 678 eligible participants of European descent, 769 incident bladder cancer cases were identified. Current smokers with a PRS in the highest tertile had a higher risk of developing bladder cancer (HR: 6.45, 95% CI: 4.51-9.24) than current smokers with a PRS in the lowest tertile (HR: 2.41, 95% CI: 1.52-3.84; P for additive interaction = <.001). A similar interaction was found for genetically predicted metabolizing NAT2 phenotype and tobacco smoking where current smokers with the slow NAT2 phenotype had an increased risk of developing bladder cancer (HR: 5.70, 95% CI: 2.64-12.30) than current smokers with the fast NAT2 phenotype (HR: 3.61, 95% CI: 1.14-11.37; P for additive interaction = .100). Our study provides support for considering both genetic and lifestyle risk factors in developing prevention measures for bladder cancer.

Associations between Child Opportunity Index and Pediatric Cardiac Surgical Outcomes.

OBJECTIVE: To assess the relationship between the Child Opportunity Index (COI), a comprehensive measurement of social determinants of health, and specific COI domains on patient-specific outcomes following congenital cardiac surgery in the metropolitan region of Atlanta, Georgia. STUDY DESIGN: In this retrospective chart review, we included patients who underwent an index operation for congenital heart disease between 2010 and 2020 in a single pediatric health care system. Patients' addresses were geocoded and mapped to census tracts. Descriptive statistics, univariable analysis, and multivariable regression models were employed to assess associations between variables and outcomes. RESULTS: Of the 7460 index surgeries, 3798 (51%) met eligibility criteria. Presence of an adverse outcome, defined as either mortality or 1 of several other major postoperative morbidities, was significantly associated with COI in the univariable model (P = .008), but not the multivariable regression model (P = .39). Postoperative hospital length of stay was significantly associated with COI (P < .001) in univariable and multivariable regression models. There was no significant association between COI and readmission within 30 days of hospital discharge in univariable (P < .094) and multivariable (P = .49) models. CONCLUSION: COI is associated with postoperative hospital length of stay but not all outcomes in patients after congenital heart surgery. By understanding the role of COI in outcomes related to cardiac surgery, targeted interventions can be developed to improve health equity.

Ambivalent Sexism and Tolerance of Violence Against Women in India.

We examined associations between sexist beliefs and tolerance of violence against women in India using a nationally representative probability sample of adults (n = 133,398). Research consistently indicates that hostile sexism fosters tolerance of violence against women. However, benevolent sexism is sometimes associated with higher tolerance and sometimes with lower tolerance of violence. We proposed that this inconsistency could be resolved by considering the source of violence: Is violence perpetrated by outsiders or intimate partners? Results of a multigroup structural equation model showed that endorsement of hostile sexism was related to greater tolerance of violence regardless of the source. In contrast, endorsement of benevolent sexism was associated with lower tolerance of violence from outsiders but was simultaneously associated with higher tolerance of spousal violence. These opposing processes indicate that although benevolent sexism promises women protection from violence, the very same ideology legitimizes spousal violence, thereby reinforcing men's power within intimate relationships.

Supramolecular Polymer Network based on Electrophilic Substitution (ES) Adduct of Furan-Triazolinedione.

Polymers with furan functionality have been the subject of extensive research on developing sustainable materials applying a limited number of dynamic covalent approaches. Herein, we introduce a facile, dynamic non-covalent approach to make a furan polymer readily accessible for self-healing applications based on its electrophilic substitution (ES) with a commercially available 1,2,4-triazoline-3,5-dione (TAD) derivative, 4-phenyl-TAD (PTAD). A tailor-made furan polymer, poly(furfuryl methacrylate) (PFMA), considering it an initial illustrative example, was rapidly ES modified with PTAD to produce furfuryl-tagged triazolidine that subsequently associated via inter-molecular hydrogen (H-) bonding to produce a thermally reversible supramolecular polymer network under ambient conditions. The H-bonded network was experimentally quantified via ATR-IR analysis and theoretically rationalized via the density functional theory (DFT) study using smaller organic model compounds analogous to the macromolecular system. Thermoreversible feature of the H-bonded triazolidine-derived supramolecular polymer network enabled the solution reprocessing and self-healing of the polymer material.

Designing a New Class of Mechanophoric Polymer Based on Epoxy-Functionalized Rhodamine Derivative.

Mechanophoric polymers are an interesting class of smart polymers which contains a special force-sensitive molecular motif that can lead to a chemical change within the polymer network in response to mechanical force. This investigation reports the design of a mechanophoric polymer based on epoxy-functionalized rhodamine via a monomeric approach. In this case, rhodamine (Rh) is modified with glycidyl methacrylate (GMA) through an epoxy-amine reaction to design a vinyl-functionalized multi-armed macromonomer (Rh-GMA), which is reacted with butyl acrylate (BA) to prepare the crosslinked polymeric film. The crosslinked polymeric film demonstrates mechanophoric properties under UV and stretching conditions.

Enhanced durability and evolution of retreatment criteria of intravitreal antivascular endothelial growth factor agents for diabetic macular edema.

PURPOSE OF REVIEW: The increasing prevalence of diabetic macular edema (DME) necessitates an updated review of treatment modalities. While the shift from laser to anti-vascular endothelial growth factor (anti-VEGF) therapy has transformed patient outcomes, benefits of these agents are not fully realized in real-world implementation relative to the setting of controlled clinical trials. This review outlines the evolution of intravitreal anti-VEGF treatment extension protocols for DME that reflect efforts to address treatment adherence challenges while optimizing visual outcomes. RECENT FINDINGS: Recent studies highlight the efficacy of extended-interval dosing with anti-VEGF agents in managing DME. Trials such as RISE/RIDE, VISTA/VIVID, and LUCIDATE have established the foundation of these regimens by demonstrating sustained visual gains with continuous treatment. However, newer trials including PROTOCOL T, KESTREL/KITE, YOSEMITE/RHINE, and PHOTON have furthered this concept, revealing that less frequent dosing of various anti-VEGF agents can maintain similar visual acuity and anatomical outcomes to traditional monthly injections. SUMMARY: The reviewed findings suggest a paradigm shift in DME treatment toward less frequent anti-VEGF injections. This has significant implications for clinical practice, potentially leading to greater adherence to treatment regimens and sustained visual function in patients, while minimizing treatment burden and healthcare costs. Further investigation into the long-term effects of extended dosing intervals is required.

Elevated HbA1c is not associated with reoperation following arthroscopic rotator cuff repair in patients with diabetes mellitus.

BACKGROUND: Hyperglycemia is a known risk factor for tendon degeneration due to oxidative stresses from production of advanced glycosylation end products. In patients with diabetes mellitus (DM), analysis of glycated hemoglobin (HbA1c) provides a 3-month window into a patient's glucose control. No guidelines exist for ideal preoperative HbA1c and glucose control prior to arthroscopic rotator cuff repair. This study evaluated if a critical HbA1c level is associated with reoperation following arthroscopic rotator cuff repair. METHODS: We retrospectively evaluated patients with DM who underwent primary arthroscopic rotator cuff repair from January 2014 to December 2018 at a single institution. Patients required a preoperative HbA1c within 3 months of surgery. Medical records were queried to evaluate for reoperation and identify the subsequent procedures performed. Univariate statistical analysis was performed to assess factors associated with reoperation (P < .05 considered significant). Threshold, area under the curve (AUC), analysis was performed to assess if a critical HbA1c value was associated with reoperation. RESULTS: A total of 402 patients met inclusion criteria. Patients had an average age of 65.5 years (range 40-89) at time of surgery; 244 (60.6%) patients were male; and average body mass index was 32.96 ± 5.81. Mean HbA1c was 7.36 (range 5.2-12). Thirty-three patients (8.2%) underwent subsequent reoperation. Six patients (1.5%) underwent capsular release and lysis of adhesions, 20 patients (5.0%) underwent a revision rotator cuff surgery, combination revision rotator cuff repair and lysis of adhesions, graft-augmented revision repair, or superior capsular reconstruction, and 7 patients (1.7%) underwent revision to reverse shoulder arthroplasty (1.7%). There were no cases of reoperation for infection. On AUC analysis, no critical HbA1c value was identified to predispose to reoperation. Interestingly, elevated preoperative American Society of Anesthesiologists (ASA) physical status classification score (2.8 vs. 2.28, P = .001) was associated with a higher reoperation rate. DISCUSSION: In patients with DM, preoperative HbA1c is not a predictive factor for surgical failure requiring reoperation. Stable glycemic control is important to a patient's overall health and may play a role in minimizing postoperative medical complications, but an elevated preoperative HbA1c should not be a strict surgical contraindication for arthroscopic rotator cuff repair. In patients with DM, an elevated ASA score is associated with an increased rate of subsequent reoperation; diabetic patients should be counseled accordingly.

Atmospheric gaseous mercury and associated health risk assessment in the economic capital of India.

Mercury cycling in coastal metropolitan areas on the west coast of India becomes complex due to the combined effects of both intensive domestic anthropogenic emissions and marine air masses. The present study is based on yearlong data of continuous measurements of gaseous elemental mercury (GEM) concentration concurrent with meteorological parameters and some air pollutants at a coastal urban site in Mumbai, on the west coast of India, for the first time. The concentration of GEM was found in a range between 2.2 and 12.3 ng/m3, with a mean of 3.1 ± 1.1 ng/m3, which was significantly higher than the continental background values in the Northern Hemisphere (~ 1.5 ng/m3). Unlike particulates, GEM starts increasing post-winter to peak during the monsoon and decrease towards winter. July had the highest concentration of GEM followed by October, and a minimum in January. GEM exhibited a distinct diurnal cycle, mainly with a broad peak in the early morning, a narrow one by nightfall, and a minimum in the afternoon. The peaks and their timing suggest the origin of urban mobility and the start of local activities. A positive correlation between SO2, PM2.5, temperature, relative humidity, and GEM indicates that emissions from local industrial plants in the Mumbai coastal area. Principal component analysis (PCA) and cluster analysis (CA) confirm this fact. Monthly back trajectory analysis showed that air mass flows are predominantly from the Arabian Sea and local human activities. Assessment of human health risks by USEPA model reveals that the hazardous quotient, HQ < 1, implies negligible carcinogenic risk. GEM observations in Mumbai during the study period are below the World Health Organization's (WHO) safe limit (200 ng/m3) for long-term inhalation.

Mid-term Surgery Outcomes in Patients With COVID-19: Results From a Nationwide Analysis.

OBJECTIVE: Determine mid-term postoperative outcomes among coronavirus disease 2019 (COVID-19)-positive (+) patients compared with those who never tested positive before surgery. BACKGROUND: COVID-19 is thought to be associated with prohibitively high rates of postoperative complications. However, prior studies have only evaluated 30-day outcomes, and most did not adjust for demographic, clinical, or procedural characteristics. METHODS: We analyzed data from surgeries performed at all Veterans Affairs hospitals between March 2020 and 2021. Kaplan-Meier curves compared trends in mortality and Cox proportional hazards models estimated rates of mortality and pulmonary, thrombotic, and septic postoperative complications between patients with a positive preoperative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test [COVID (+)] and propensity score-matched COVID-negative (-) patients. RESULTS: Of 153,741 surgical patients, 4778 COVID (+) were matched to 14,101 COVID (-). COVID (+) status was associated with higher postoperative mortality ( P <0.0001) with a 6-month survival of 94.2% (95% confidence interval: 93.2-95.2) versus 96.0% (95% confidence interval: 95.7.0-96.4) in COVID (-). The highest mortality was in the first 30 postoperative days. Hazards for mortality and postoperative complications in COVID (+) decreased with increasing time between testing COVID (+) and date of surgery. COVID (+) patients undergoing elective surgery had similar rates of mortality, thrombotic and septic complications, but higher rates of pulmonary complications than COVID (-) patients. CONCLUSIONS: This is the first report of mid-term outcomes among COVID-19 patients undergoing surgery. COVID-19 is associated with decreased overall and complication-free survival primarily in the early postoperative period, delaying surgery by 5 weeks or more reduces risk of complications. Case urgency has a multiplicative effect on short-term and long-term risk of postoperative mortality and complications.

Beyond traditional therapy: Mucoadhesive polymers as a new frontier in oral cancer management.

In recent times mucoadhesive drug delivery systems are gaining popularity in oral cancer. It is a malignancy with high global prevalence. Despite significant advances in cancer therapeutics, improving the prognosis of late-stage oral cancer remains challenging. Targeted therapy using mucoadhesive polymers can improve oral cancer patients' overall outcome by offering enhanced oral mucosa bioavailability, better drug distribution and tissue targeting, and minimizing systemic side effects. Mucoadhesive polymers can also be delivered via different formulations such as tablets, films, patches, gels, and nanoparticles. These polymers can deliver an array of medicines, making them an adaptable drug delivery approach. Drug delivery techniques based on these mucoadhesive polymers are gaining traction and have immense potential as a prospective treatment for late-stage oral cancer. This review examines leading research in mucoadhesive polymers and discusses their potential applications in treating oral cancer.

Heritable gene expression variability and stochasticity govern clonal heterogeneity in circadian period.

A ubiquitous feature of the circadian clock across life forms is its organization as a network of cellular oscillators, with individual cellular oscillators within the network often exhibiting considerable heterogeneity in their intrinsic periods. The interaction of coupling and heterogeneity in circadian clock networks is hypothesized to influence clock's entrainability, but our knowledge of mechanisms governing period heterogeneity within circadian clock networks remains largely elusive. In this study, we aimed to explore the principles that underlie intercellular period variation in circadian clock networks (clonal period heterogeneity). To this end, we employed a laboratory selection approach and derived a panel of 25 clonal cell populations exhibiting circadian periods ranging from 22 to 28 h. We report that a single parent clone can produce progeny clones with a wide distribution of circadian periods, and this heterogeneity, in addition to being stochastically driven, has a heritable component. By quantifying the expression of 20 circadian clock and clock-associated genes across our clone panel, we found that inheritance of expression patterns in at least three clock genes might govern clonal period heterogeneity in circadian clock networks. Furthermore, we provide evidence suggesting that heritable epigenetic variation in gene expression regulation might underlie period heterogeneity.

Bayesian methods: a potential path forward for sepsis trials.

BACKGROUND: Given the success of recent platform trials for COVID-19, Bayesian statistical methods have become an option for complex, heterogenous syndromes like sepsis. However, study design will require careful consideration of how statistical power varies using Bayesian methods across different choices for how historical data are incorporated through a prior distribution and how the analysis is ultimately conducted. Our objective with the current analysis is to assess how different uses of historical data through a prior distribution, and type of analysis influence results of a proposed trial that will be analyzed using Bayesian statistical methods. METHODS: We conducted a simulation study incorporating historical data from a published multicenter, randomized clinical trial in the US and Canada of polymyxin B hemadsorption for treatment of endotoxemic septic shock. Historical data come from a 179-patient subgroup of the previous trial of adult critically ill patients with septic shock, multiple organ failure and an endotoxin activity of 0.60-0.89. The trial intervention consisted of two polymyxin B hemoadsorption treatments (2 h each) completed within 24 h of enrollment. RESULTS: In our simulations for a new trial of 150 patients, a range of hypothetical results were observed. Across a range of baseline risks and treatment effects and four ways of including historical data, we demonstrate an increase in power with the use of clinically defensible incorporation of historical data. In one possible trial result, for example, with an observed reduction in risk of mortality from 44 to 37%, the probability of benefit is 96% with a fixed weight of 75% on prior data and 90% with a commensurate (adaptive-weighting) prior; the same data give an 80% probability of benefit if historical data are ignored. CONCLUSIONS: Using Bayesian methods and a biologically justifiable use of historical data in a prior distribution yields a study design with higher power than a conventional design that ignores relevant historical data. Bayesian methods may be a viable option for trials in critical care medicine where beneficial treatments have been elusive.

Glycopolymer Decorated pH-Dependent Ratiometric Fluorescent Probe Based on Förster Resonance Energy Transfer for the Detection of Cancer Cells.

Development of fluorescent imaging probes is an important topic of research for the early diagnosis of cancer. Based on the difference between the cellular environment of tumor cells and normal cells, several "smart" fluorescent probes have been developed. In this work, a glycopolymer functionalized Förster resonance energy transfer (FRET) based fluorescent sensor is developed, which can monitor the pH change in cellular system. One-pot sequential reversible addition-fragmentation chain transfer (RAFT)polymerization technique is employed to synthesize fluorescent active triblock glycopolymer that can undergo FRET change on the variation of pH. A FRET pair, fluorescein o-acrylate (FA) and 7-amino-4-methylcoumarin (AMC) is linked via a pH-responsive polymer poly [2-(diisopropylamino)ethyl methacrylate] (PDPAEMA), which can undergo reversible swelling/deswelling under acidic/neutral condition. The presence of glycopolymer segment provides stability, water solubility, and specificity toward cancer cells. The cellular FRET experiments on cancer cells (MDA MB 231) and normal cells (3T3 fibroblast cells) demonstrate that the material is capable of distinguishing cells as a function of pH change.

Isoflavone and soy food intake and risk of lung cancer in never smokers: report from prospective studies in Japan and China.

PURPOSE: Evidence from several cohorts has suggested that a higher intake of isoflavone is associated with lower risk of lung cancer in never smokers, but the association has not been investigated by histologic type of lung cancer. Adenocarcinoma is a common histologic type found in never smokers. We hypothesized that a higher intake of isoflavone is associated with a lower risk of lung adenocarcinoma among never smokers. Here, we examined the associations of isoflavone and soy food intake with lung cancer and its histologic types in never smokers. METHODS: We performed a pooled analysis using data from the Japan Public Health Center-based Prospective Study, Shanghai Women's Health Study and Shanghai Men's Study with 147,296 never smokers aged 40-74 years with no history of cancer. During 1,990,040 person-years of follow-up, 1247 lung cancer cases were documented. Dietary isoflavone and soy food intake were assessed using a food-frequency questionnaire. Multivariable Cox proportional hazards models assessed the associations between isoflavone and soy intake with incidence of lung cancer by histologic type. RESULTS: A higher intake of dietary isoflavone and soy food were associated with reduced risk of lung adenocarcinoma. The multivariable hazard ratios (HRs) (95% CI) of risk of lung adenocarcinoma for the highest versus lowest intakes of isoflavone and soy food were 0.74 (0.60-0.92) and 0.78 (0.63-0.96), respectively. The multivariable HRs of risk of lung adenocarcinoma associated with each 10 mg/day increase in isoflavone and each 50 g/day increase in soy food intake were 0.81 (0.70-0.94) and 0.84 (0.73-0.96), respectively. CONCLUSION: Higher intake of isoflavone and soy food was associated with lower risk of lung adenocarcinoma in never smokers.

Multicomponent Home-based Physical Therapy Versus Usual Care for Recovery After Hip Fracture.

OBJECTIVE: To quantify the effect of 2 home-based 16-week multi-component physical therapy interventions on functional recovery compared to usual care after hip fracture. DESIGN: Cross-study comparison using participants from the Community Ambulation Project (CAP; a randomized controlled trial) were compared to the Baltimore Hip Studies-seventh cohort (BHS-7; an observational cohort study) at 3 different time points (CAP: 15, 31, 55 weeks; BHS-7: 8, 26, and 52 weeks). SETTING: General community PARTICIPANTS: Combined convenience sample of hip-fracture patients 8-26 weeks post admission from a prospective cohort study and randomized controlled trial. (N=549) INTERVENTIONS: CAP participants were randomized to one of 2 interventions (PUSH: specific multi-component intervention; PULSE: non-specific multi-component intervention) after standard rehabilitation; BHS-7 participants received usual care. MAIN OUTCOME MEASURES: Mean function (as measured by Short Physical Performance Battery (SPPB) and gait speed) was estimated in each cohort as quadratic functions of time using data from 3 post-fracture assessments in both studies (CAP: 15, 31, 55 weeks; BHS-7: 8, 26, and 52 weeks). RESULTS: The harmonized samples included 101 PUSH, 100 PULSE, and 128 BHS-7 participants that had different demographic and clinical characteristics. Mean baseline SPPB scores (meters per second) were PUSH: 5.5 (SD=2.2), PULSE: 5.5 (SD=2.4), and BHS-7: 4.6 (SD=2.5); and mean gait speeds were 0.60 m/s (SD=0.20) for PUSH, 0.59 m/s (SD=0.17) for PULSE, and 0.46 m/s SD=(0.21) for BHS-7, respectively. Estimated between-group differences for SPPB improvement from 75 days to 1-year post admission were 0.7 (P=.04) in PUSH vs BHS-7; and 0.9 (P=.01) in PULSE vs BHS-7. Mean differences in change in gait speed were 0.08 (P=.002) for PUSH vs BHS-7; and 0.06 (P=.02) PULSE vs BHS-7 (P=.02). CONCLUSIONS: Findings from this cross-study comparison that combined participants from 2 separate studies, with different designs and samples, suggest that home-based multi-component physical therapy programs were associated with greater functional improvement after hip fracture compared to usual care.

Characterization of Biomineralizing and Plant Growth-Promoting Attributes of Lithobiontic Bacteria.

The application of mineral-solubilizing, plant growth-promoting bacteria as inoculants offers a promising alternative to chemical fertilizers. In the present study, lithic bacterial isolates were evaluated for mineral solubilization and plant growth-promoting potential. Among the 57 lithic bacterial isolates associated with different rock samples collected from various locations in Meghalaya, India, nine K-solubilizing isolates, six S-solubilizing isolates, five P- and Si-solubilizing isolates, and three Zn-solubilizing isolates with notable indole-3-acetic acid and siderophore production, and ACC deaminase activity were selected for further study. Based on 16S rRNA gene sequence analysis, isolates were affiliated to nine different genera (Arthrobacter, Acinetobacter, Pseudomonas, Halopseudomonas, Bacillus, Neobacillus, Peribacillus, Pantoea, and Priestia). On performing rice seed germination potentials, Pantoea agglomerans BL26, Priestia megaterium BL9, Bacillus subtilis GP2, Halopseudomonas xinjiangensis BL29, and Pseudomonas sp. BM1 were selected for in vitro pot experiments, being the most potent isolates. Following inoculation, all five isolates were found to significantly enhance growth of rice plants (P < 0.05). The maximum shoot length increased due to P. megaterium BL9, the maximum root length increased due to H. xinjiangensis BL29, and the maximum plant fresh weight increased due to P. megaterium BL9. The findings concluded that these five lithic bacterial isolates have potent plant growth-promoting potential with possible prospection through field trials. To the best of available literature, this is a first report on the characterization of lithic bacterial isolates as mineral solubilizers and plant growth promoters.

PET imaging characteristics of neuromuscular choristoma and associated desmoid-type fibromatosis.

BACKGROUND: Neuromuscular choristoma (NMC) is a rare peripheral nerve lesion characterized by abnormal presence of muscle within nerve. Associated desmoid-type fibromatosis (NMC-DTF) often develops. We report 18F-fluorodeoxyglucose positron emission tomography (FDG PET) characteristics of NMC and NMC-DTF and propose that increased FDG activity within NMCs may be associated with subclinical NMC-DTF or NMC-DTF "precursor" tissue. METHODS: Our institutional database was searched for all NMC cases. Inclusion criteria were 1) confirmed diagnosis of NMC with or without biopsy, and 2) available PET and MRI studies. PET data included SUVmax and SUVmean of NMCs, contralateral limb normal skeletal muscle and unaffected nerves, and SUVmax of NMC-DTF if present. SUV values were compared using paired t-test. A p value of < 0.05 was considered statistically significant. RESULTS: Our cohort consisted of 9 patients with NMC, 8 cases involving sciatic nerve and 1 of brachial plexus. On PET imaging, all NMC-affected nerve segments showed significantly higher FDG uptake (SUVmax/mean) compared to both contralateral normal nerve and normal skeletal muscle (all P < 0.05). Similar to sporadic DTF, NMC-DTF was highly FDG-avid (average SUVmax of 4.2). SUVmax in NMC with or without concurrent NMC-DTF did not differ (p = 0.76). Within NMC-affected nerve segment, FDG activity was relatively higher in areas with low T1/T2 MR signal. CONCLUSION: All NMCs were more FDG avid compared to both normal skeletal muscle and contralateral unaffected nerve, arguing against the presence of heterotopic muscle in NMC as the source of FDG avidity. FDG avidity within NMC may reflect subclinical NMC-DTF or a precursor lesion, as NMC-DTF are highly FDG-avid, and the highest regions of FDG avidity in NMC occurred in regions with MR characteristics associated with NMC-DTF (i.e., lower T1/T2 signal). We believe that the integration of FDG PET with serial MR imaging in patient follow up will clarify its utility in both detection and surveillance of NMC-DTF.

Diagnostic value of proximal cutaneous nerve biopsy in brachial and lumbosacral plexus pathologies.

BACKGROUND: Brachial and lumbosacral plexopathies can result from numerous non-traumatic etiologies, including those of inflammatory, autoimmune, or neoplastic origin, that often require nerve biopsy for diagnosis. The purpose of this study was to evaluate the diagnostic efficacy of medial antebrachial cutaneous nerve (MABC) and posterior femoral cutaneous nerve (PFCN) nerve biopsies in proximal brachial and lumbosacral plexus pathology. METHOD: Patients undergoing MABC or PFCN nerve biopsies at a single institution were reviewed. Patient demographics, clinical diagnosis, symptom duration, intraoperative findings, post-operative complications, and pathology results were recorded. Biopsy results were classified as diagnostic, inconclusive, or negative based on the final pathology. RESULTS: Thirty patients undergoing MABC biopsies in the proximal arm or axilla and five patients with PFCN biopsies in the thigh or buttock were included. MABC biopsies were diagnostic in 70% of cases overall and 85% diagnostic in cases where pre-operative MRI also demonstrated abnormalities in the MABC. PFCN biopsies were diagnostic in 60% of cases overall and in 100% of patients with abnormal pre-operative MRIs. There were no biopsy-related post-operative complications in either group. CONCLUSIONS: In diagnosing non-traumatic etiologies of brachial and lumbosacral plexopathies, proximal biopsies of the MABC and PFCN provide high diagnostic value with low donor morbidity.

Synchronization, clustering, and weak chimeras in a densely coupled transcription-based oscillator model for split circadian rhythms.

The synchronization dynamics for the circadian gene expression in the suprachiasmatic nucleus is investigated using a transcriptional circadian clock gene oscillator model. With global coupling in constant dark (DD) conditions, the model exhibits a one-cluster phase synchronized state, in dim light (dim LL), bistability between one- and two-cluster states and in bright LL, a two-cluster state. The two-cluster phase synchronized state, where some oscillator pairs synchronize in-phase, and some anti-phase, can explain the splitting of the circadian clock, i.e., generation of two bouts of daily activities with certain species, e.g., with hamsters. The one- and two-cluster states can be reached by transferring the animal from DD or bright LL to dim LL, i.e., the circadian synchrony has a memory effect. The stability of the one- and two-cluster states was interpreted analytically by extracting phase models from the ordinary differential equation models. In a modular network with two strongly coupled oscillator populations with weak intragroup coupling, with appropriate initial conditions, one group is synchronized to the one-cluster state and the other group to the two-cluster state, resulting in a weak-chimera state. Computational modeling suggests that the daily rhythms in sleep-wake depend on light intensity acting on bilateral networks of suprachiasmatic nucleus (SCN) oscillators. Addition of a network heterogeneity (coupling between the left and right SCN) allowed the system to exhibit chimera states. The simulations can guide experiments in the circadian rhythm research to explore the effect of light intensity on the complexities of circadian desynchronization.