Unprocessed genomic uracil as a source of DNA replication stress in cancer cells

Alterations of bases in DNA constitute a major source of genomic instability. It is believed that base alterations trigger base excision repair (BER), generating DNA repair intermediates interfering with DNA replication. Here, we show that genomic uracil, a common type of base alteration, induces DNA replication stress (RS) without being processed by BER. In the absence of uracil DNA glycosylase (UNG), genomic uracil accumulates to high levels, DNA replication forks slow down, and PrimPol-mediated repriming is enhanced, generating single-stranded gaps in nascent DNA. ATR inhibition in UNG-deficient cells blocks the repair of uracil-induced gaps, increasing replication fork collapse and cell death. Notably, a subset of cancer cells upregulates UNG2 to suppress genomic uracil and limit RS, and these cancer cells are hypersensitive to co-treatment with ATR inhibitors and drugs increasing genomic uracil. These results reveal unprocessed genomic uracil as an unexpected source of RS and a targetable vulnerability of cancer cells.

DrugMap: A quantitative pan-cancer analysis of cysteine ligandability

Cysteine-focused chemical proteomic platforms have accelerated the clinical development of covalent inhibitors for a wide range of targets in cancer. However, how different oncogenic contexts influence cysteine targeting remains unknown. To address this question, we have developed "DrugMap," an atlas of cysteine ligandability compiled across 416 cancer cell lines. We unexpectedly find that cysteine ligandability varies across cancer cell lines, and we attribute this to differences in cellular redox states, protein conformational changes, and genetic mutations. Leveraging these findings, we identify actionable cysteines in NF-κB1 and SOX10 and develop corresponding covalent ligands that block the activity of these transcription factors. We demonstrate that the NF-κB1 probe blocks DNA binding, whereas the SOX10 ligand increases SOX10-SOX10 interactions and disrupts melanoma transcriptional signaling. Our findings reveal heterogeneity in cysteine ligandability across cancers, pinpoint cell-intrinsic features driving cysteine targeting, and illustrate the use of covalent probes to disrupt oncogenic transcription-factor activity.

Novel Approaches with HIF-2α Targeted Therapies in Metastatic Renal Cell Carcinoma

Germline inactivation of the Von Hippel-Lindau (VHL) tumor suppressor is the defining hallmark in hereditary VHL disease and VHL-associated renal cell carcinoma (RCC). However, somatic VHL mutations are also observed in patients with sporadic RCC. Loss of function VHL mutations result in constitutive activation of hypoxia-inducible factor-2 alpha (HIF-2α), which leads to increased expression of HIF target genes that promote angiogenesis and tumor growth. As of 2023, belzutifan is currently the only approved HIF-2α inhibitor for both VHL-associated and sporadic metastatic RCC (mRCC). However, there is potential for resistance with HIF-2α inhibitors which warrants novel HIF-2α-targeting strategies. In this review, we discuss the potential resistance mechanisms with belzutifan and current clinical trials evaluating novel combinations of belzutifan with other targeted therapies and immune checkpoint inhibitors which may enhance the efficacy of HIF-2α targeting. Lastly, we also discuss newer generation HIF-2α inhibitors that are currently under early investigation and outline future directions and challenges with HIF-2α inhibitors for mRCC.

Parathyroid gland detection using an intraoperative autofluorescence handheld imager - early feasibility study

Introduction

Parathyroid glands may be compromised during thyroid surgery which can lead to hypoparathyroidism and hypocalcemia. Identifying the parathyroid glands relies on the surgeon's experience and the only way to confirm their presence was through tissue biopsy. Near infrared autofluorescence technology offers an opportunity for real-time, non-invasive identification of the parathyroid glands.

Methods

We used a new research prototype (hANDY-I) developed by Optosurgical, LLC. It offers coaxial excitation light and a dual-Red Green Blue/Near Infrared sensor that guides anatomical landmarks and can aid in identification of parathyroid glands by showing a combined autofluorescence and colored image simultaneously.

Results

We tested the imager during 23 thyroid surgery cases, where initial clinical feasibility data showed that out of 75 parathyroid glands inspected, 71 showed strong autofluorescence signal and were correctly identified (95% accuracy) by the imager.

Conclusions

The hANDY-I prototype demonstrated promising results in this feasibility study by aiding in real-time visualization of the parathyroid glands. However, further testing by conducting randomized clinical trials with a bigger sample size is required to study the effect on levels of hypoparathyroidism and hypocalcemia.

Multiscale architecture for fast optical addressing and control of large-scale qubit arrays

This paper presents a technique for rapid site-selective control of the quantum state of particles in a large array using the combination of a fast deflector (e.g., an acousto-optic deflector) and a relatively slow spatial light modulator (SLM). The use of SLMs for site-selective quantum state manipulation has been limited due to slow transition times that prevent rapid, consecutive quantum gates. By partitioning the SLM into multiple segments and using a fast deflector to transition between them, it is possible to substantially reduce the average time increment between scanner transitions by increasing the number of gates that can be performed for a single SLM full-frame setting. We analyzed the performance of this device in two different configurations: In configuration 1, each SLM segment addresses the full qubit array; in configuration 2, each SLM segment addresses a subarray and an additional fast deflector positions that subarray with respect to the full qubit array. With these hybrid scanners, we calculated qubit addressing rates that are tens to hundreds of times faster than using an SLM alone.

Warming signals in temperate reef communities following more than a decade of ecological stability

Ecosystem structure and function are increasingly threatened by changing climate, with profound effects observed globally in recent decades. Based on standardized visual censuses of reef biodiversity, we describe 27 years of community-level change for fishes, mobile macroinvertebrates and macroalgae in the Tasmanian ocean-warming hotspot. Significant ecological change was observed across 94 reef sites (5-10 m depth range) spanning four coastal regions between three periods (1992-95, 2006-07, 2017-19), which occurred against a background of pronounced sea temperature rise (+0.80°C on average). Overall, fish biomass increased, macroinvertebrate species richness and abundance decreased and macroalgal cover decreased, particularly during the most recent decade. While reef communities were relatively stable and warming was slight between the 1990s and mid-2000s (+0.12°C mean temperature rise), increased abundances of warm affinity fishes and invertebrates accompanied warming during the most recent decade (+0.68°C rise). However, significant rises in the community temperature index (CTI) were only found for fishes, invertebrates and macroalgae in some regions. Coastal warming was associated with increased fish biomass of non-targeted species in fished zones but had little effect on reef communities within marine reserves. Higher abundances of larger fishes and lobsters inside reserves appeared to negate impacts of 'thermophilization'.

A coaxial excitation, dual-red-green-blue/near-infrared paired imaging system toward computer-aided detection of parathyroid glands in situ and ex vivo

Early and precise detection of parathyroid glands (PGs) is a challenging problem in thyroidectomy due to their small size and similar appearance to surrounding tissues. Near-infrared autofluorescence (NIRAF) has stimulated interest as a method to localize PGs. However, high incidence of false positives for PGs has been reported with this technique. We introduce a prototype equipped with a coaxial excitation light (785 nm) and a dual-sensor to address the issue of false positives with the NIRAF technique. We test the clinical feasibility of our prototype in situ and ex vivo using sterile drapes on 10 human subjects. Video data (1287 images) of detected PGs were collected to train, validate and compare the performance for PG detection. We achieved a mean average precision of 94.7% and a 19.5-millisecond processing time/detection. This feasibility study supports the effectiveness of the optical design and may open new doors for a deep learning-based PG detection method.

Integrative analysis of scRNA-seq and scATAC-seq revealed transit-amplifying thymic epithelial cells expressing autoimmune regulator

Medullary thymic epithelial cells (mTECs) are critical for self-tolerance induction in T cells via promiscuous expression of tissue-specific antigens (TSAs), which are controlled by the transcriptional regulator, AIRE. Whereas AIRE-expressing (Aire⁺) mTECs undergo constant turnover in the adult thymus, mechanisms underlying differentiation of postnatal mTECs remain to be discovered. Integrative analysis of single-cell assays for transposase-accessible chromatin (scATAC-seq) and single-cell RNA sequencing (scRNA-seq) suggested the presence of proliferating mTECs with a specific chromatin structure, which express high levels of Aire and co-stimulatory molecules, CD80 (Aire⁺CD80^hi). Proliferating Aire⁺CD80^hi mTECs detected using Fucci technology express a minimal number of Aire-dependent TSAs and are converted into quiescent Aire⁺CD80^hi mTECs expressing high levels of TSAs after a transit amplification. These data provide evidence for the existence of transit-amplifying Aire⁺mTEC precursors during the Aire⁺mTEC differentiation process of the postnatal thymus.

A pilot feasibility study to assess vascularity and perfusion of parathyroid glands using a portable hand-held imager

OBJECTIVES

Intraoperative localization and preservation of parathyroid glands (PGs) are challenging during thyroid surgery. A new noninvasive technique of combined near-infrared PG autofluorescence detection and dye-free imaging angiography that allows intraoperative feedback has recently been introduced. The objective of this study was to evaluate this technique in real-time.

MATERIALS AND METHODS

A pilot feasibility study of a portable imaging device in four patients who underwent either thyroid lobectomy or total thyroidectomy is presented. PG autofluorescence and vascularity/tissue perfusion were monitored using a real-time screen display during the surgical procedure.

RESULTS

Three lobectomies and one total thyroidectomy were performed. Among the nine PGs identified by the operating surgeon, eight PGs were confirmed using the autofluorescence device. Each PG was successfully determined to be either well-perfused or devascularized, and devascularized PGs were autotransplanted.

CONCLUSIONS

The preliminary results suggest that the combination of PG autofluorescence detection and dye-free angiography can potentially be used to assess PG function. With further validation studies, the effectiveness of this technique in clinical practice can be further delineated.

Development of a non-invasive, dual-sensor handheld imager for intraoperative preservation of parathyroid glands

Intraoperative localization and preservation of parathyroid glands (PTGs) are challenging during thyroid surgery. Using a technique of combined near-infrared PTG autofluorescence detection and dye-free imaging angiography, this study developed a portable device for localization of PTGs and assessment of viability by confirming tissue perfusion. The imager's performance was evaluated through a pilot clinical study (N=10).

Laparoscopic cholecystectomy in a swine model using a novel near-infrared fluorescent IV dye (BL-760)

BACKGROUND AND OBJECTIVES

Bile duct injury during laparoscopic cholecystectomy has an incidence rate of 1%-2% and commonly appears under conditions of severe inflammation, adhesion, or unexpected anatomical variations. Despite the difficulties and rising concerns of identifying bile duct during surgeries, surgeons do not have a specific modality to identify bile duct except intraoperative cholangiography. While no biliary-specific fluorescent dye exists for clinical use, our team has previously described the development of a preclinical biliary-specific dye, BL-760. Here, we present our study of laparoscopic cholecystectomy using the fluorescent dye in a swine model.

STUDY DESIGN/MATERIALS AND METHODS

With an approval from Institutional Animal Care and Use Committee, two 20-25 kg swine underwent laparoscopic abdominal surgery using a Food and Drug Administration-cleared fluorescent laparoscopic system. Images of the liver and gallbladder were taken both before and after intravenous injection of the novel fluorescent dye. The dye was dosed at 60 μg/kg and injected via the ear vein. The amount of time taken to visualize fluorescence in the biliary tract was measured. Fluorescent signal was observed after injection, and target-to-background ratio (TBR) of the biliary tract to surrounding cystic artery and liver parenchyma was measured.

RESULTS

Biliary tract visualization under fluorescent laparoscopy was achieved within 5 min after the dye injection without any adverse effects. Cystic duct and extrahepatic duct were clearly visualized and identified with TBR values of 2.19 and 2.32, respectively, whereas no fluorescent signal was detected in liver. Cystic duct and artery were successfully ligated by an endoscopic clip applier with the visual assistance of highlighted biliary tract images. Laparoscopic cholecystectomy was completed within 30 min in each case without any complications.

CONCLUSIONS

BL-760 is a novel preclinical fluorescent dye useful for intraoperative identification and visualization of biliary tract. Such fluorescent dye that is exclusively metabolized by liver and rapidly excreted into biliary tract would be beneficial for all types of hepato-biliary surgeries. With the validation of additional preclinical data, this novel dye has potential to be a valuable tool to prevent any iatrogenic biliary injuries and/or bile leaks during laparoscopic abdominal and liver surgeries.

Monitoring Bacterial Translation Rates Genome-Wide

Modern DNA sequencing technologies have allowed for the sequencing of tens of thousands of bacterial genomes. While this explosion of information has brought about new insights into the diversity of the prokaryotic world, much less is known of the identity of proteins encoded within these genomes, as well as their rates of production. The advent of ribosome profiling, or the deep sequencing of ribosome-protected footprints, has recently enabled the systematic evaluation of every protein-coding region in a given experimental condition, the rates of protein production for each gene, and the variability in translation rates across each message. Here, I provide an update to the bacterial ribosome profiling approach, with a particular emphasis on a simplified strategy to reduce cloning time.

Combined effects of sous-vide cooking conditions on meat and sensory quality characteristics of chicken breast meat

This study investigated the combined effects of cooking temperature and time on the meat and eating quality characteristics of the sous-vide chicken breast. For the control group, chicken breast samples were cooked in a convection oven until the internal temperature reached 71°C. Each sample for sous-vide cooking was vacuum packaged and then cooked under continuous thermocontrolled conditions in a water bath at 6 combinations of cooking temperature (60 and 70°C) and time (1, 2, and 3 h). Sous-vide cooked chicken meat at 60°C for 1 h (SV60-1h) showed lower cooking loss (6.58 vs. 26.5%, P < 0.05), Warner-Bratzler shear force (21.7 vs. 29.1 N, P < 0.05), and hardness (9.40 vs. 17.3 N, P < 0.05) than meat cooked by conventional oven. Similar to the objective tenderness parameters, cooked chicken meat from the SV60 treatments for all cooking times showed higher scores in all the tenderness attributes than the control group (P < 0.05). However, a higher flavor intensity was observed in the SV70-3h and control groups than in the SV60 treatments (P < 0.05). Owing to a lesser developed flavor in chicken meat from the SV60-1h treatment, the SV60-2h and 3h treatments were assigned a higher acceptability rating for overall impression (P < 0.05). Therefore, cooking temperature and time of sous-vide significantly influenced the physicochemical and palatability characteristics of chicken breast. In this study, the optimum conditions for the sous-vide chicken breast are to continuously cook at 60°C for 2 to 3 h to improve sensory quality characteristics without reducing the water-holding capacity.

Super-Strong Carbon Nanotube Fibers Achieved by Engineering Gas Flow and Postsynthesis Treatment

Carbon nanotube fibers (CNTFs) are directly spun from a floating-catalyst chemical vapor deposition apparatus using gas-phase carbon and an iron nanocatalyst. The essential synthesis and post-treatment factors that affect the strength of CNTFs are investigated to obtain CNTFs with greater strength than those of any previously reported high-performance fibers. The key factors optimized included the degree of rotational flow inside the reactor, the ratio of the starting materials, and the postsynthesis treatment conditions. The formation of rotational gas flow inside the reactor was confirmed by computational fluid dynamics simulations, and the feed ratio of the starting materials was optimized through response surface methodology. In addition, a reproducible and highly efficient postsynthesis treatment method was established. Pristine CNTFs with a high specific strength (SS) (average 2.2 N/tex, max. 2.3 N/tex) were synthesized through decreased rotational flow and optimization of the CNTF synthesis conditions. To improve the SS of the CNTFs further, we adopted an acid wet-stretching method that included washing and heat treatment. This drastically increased the SS of the CNTFs (average 5.5 N/tex, max. 6.4 N/tex) because of the decrease in the volume of the pores between the CNT bundles.

Gene expression and cell identity controlled by anaphase-promoting complex

Metazoan development requires robust proliferation of progenitor cells, whose identities are established by tightly controlled transcriptional networks ¹. As gene expression is globally inhibited during mitosis, the transcriptional programs defining cell identity must be restarted in each cell cycle ^2-5, yet how this is accomplished is poorly understood. Here, we identified a ubiquitin-dependent mechanism that integrates gene expression with cell division to preserve cell identity. We found that WDR5 and TBP, which bind active interphase promoters ^6,7, recruit the anaphase-promoting complex (APC/C) to specific transcription start sites (TSS) during mitosis. This allows APC/C to decorate histones with K11/K48-branched ubiquitin chains that recruit p97/VCP and the proteasome and ensure rapid expression of pluripotency genes in the next cell cycle. Mitotic exit and transcription re-initiation are thus controlled by the same regulator, APC/C, which provides a robust mechanism to maintain cell identity through cell division.

Synthetic chimeric nucleases function for efficient genome editing

CRISPR-Cas systems have revolutionized genome editing across a broad range of biotechnological endeavors. Many CRISPR-Cas nucleases have been identified and engineered for improved capabilities. Given the modular structure of such enzymes, we hypothesized that engineering chimeric sequences would generate non-natural variants that span the kinetic parameter landscape, and thus provide for the rapid selection of nucleases fit for a particular editing system. Here, we design a chimeric Cas12a-type library with approximately 560 synthetic chimeras, and select several functional variants. We demonstrate that certain nuclease domains can be recombined across distantly related nuclease templates to produce variants that function in bacteria, yeast, and human cell lines. We further characterize selected chimeric nucleases and find that they have different protospacer adjacent motif (PAM) preferences and the M44 chimera has higher specificity relative to wild-type (WT) sequences. This demonstration opens up the possibility of generating nuclease sequences with implications across biotechnology.

P4580The effect of anesthetic techniques on cardiac troponin-T after non-cardiac surgery

Background

The effects of anesthetics on cardiac protection and clinical outcomes have shown conflicting results in patients undergoing non-cardiac surgery. Unlike cardiac surgeries in which cardio-protective effects of anesthetic techniques have been reported, it lacks evidence and reproducibility in non-cardiac surgery. A current generation high-sensitivity cardiac troponin (hs-cTnI) is known to detect perioperative myocardial injury in non-cardiac surgery which is closely related to clinical outcomes. In this study, we hypothesized that balanced anesthesia using both remifentanil and volatile agents is the most effective in reducing postoperative myocardial injury, and compared the incidence of postoperative myocardial injury among different types of general anesthesia.

Methods

We analyzed the data of 3555 patients who underwent general anesthesia for non-cardiac surgery in our hospital between February 2010 and December 2016. In all patients, hs-cTnI was detected in preoperative period and postoperative period within 48 hours. Major exclusion criteria was troponin elevation before surgery. Patients were stratified into three groups; 661 patients who were received propofol-remifentanil total intravenous anesthesia (TIVA group), 1279 patients who were received volatile anesthesia without remifentanil (Volatile group) and 1622 patients who were received volatile anesthesia with remifentanil (Balanced group). The Primary outcome was troponin elevation [hs-cTnI≥0.04 ng/mL] within post-operative within 48 hours, and the incidence of postoperative complications such as postoperative acute kidney injury, new-onset atrial fibrillation and in-hospital mortality were also compared.

Results

The occurrence of myocaridial injury were significant difference between three groups. The occurrence of myocardial injury was significantly lower in the Balanced group than in Volatile group after adjustment (Odds ratio (OR) = 0.727; 95% confidence interval (CI) = 0.59–0.89; P-value = 0.002). Balanced group and TIVA group showed comparable results in risk of postoperative troponin elevation after adjustment (OR 1.131; 95% CI 0.96–1.33; P-value = 0.133). The incidence of troponin elevation was significantly higher in Volatile group than TIVA group after adjustment (OR 1.6; 95% CI 0.52–0.96; P-value = 0.005). The incidence of AKI was significantly lower in Balanced group than Volatile group after adjustment (OR 0.637; 95% CI 0.49–0.81; P-value <0.001).

Conclusion

The remifentanil combination during general anesthesia may be associated with myocardial protection effect in patients undergoing non-cardiac surgery. Whether this impact leads to adverse long-term outcome remains unclear, and requires further investigation.

Utility of the laryngeal handshake method for identifying the cricothyroid membrane

BACKGROUND

The cricothyroid membrane is the most commonly accessed location for invasive surgical airway. Although the laryngeal handshake method is recommended for identifying the cricothyroid membrane, there is no clinical data regarding the utility of the laryngeal handshake method in cricothyroid membrane identification. The objective of this study was to compare the accuracy of cricothyroid membrane identification between the laryngeal handshake method and simple palpation.

METHODS

After anaesthesia induction, the otorhinolaryngology resident and anaesthesia resident identified and marked the needle insertion point for cricothyroidotomy using simple palpation and the laryngeal handshake method, respectively. The cricothyroid membrane was confirmed with ultrasonography. Identification was determined successful if the marked point was placed within the longitudinal area of the cricothyroid membrane and within 5 mm from midline transversely. The accuracy of cricothyroid membrane identification using the laryngeal handshake method and simple palpation was compared.

RESULTS

A total of 123 patients were enrolled. The cricothyroid membrane was correctly identified in 87 (70.7%, 95% confidence interval 61.8-78.6%) patients using the laryngeal handshake method compared to 78 (63.4%, 95% confidence interval 54.3-71.9%) patients using simple palpation (P = .188). The time required to identify the cricothyroid membrane was longer when using the laryngeal handshake method (15 [3-48] seconds vs 10.9 [3-55] seconds, P = .003).

CONCLUSION

The success rate of identifying the cricothyroid membrane was similar among the anesthesiologists who performed the laryngeal handshake method and also among otorhinolaryngologists who used simple palpation.

Principles of Ubiquitin-Dependent Signaling

Ubiquitylation is an essential posttranslational modification that controls cell division, differentiation, and survival in all eukaryotes. By combining multiple E3 ligases (writers), ubiquitin-binding effectors (readers), and de-ubiquitylases (erasers) with functionally distinct ubiquitylation tags, the ubiquitin system constitutes a powerful signaling network that is employed in similar ways from yeast to humans. Here, we discuss conserved principles of ubiquitin-dependent signaling that illustrate how this posttranslational modification shapes intracellular signaling networks to establish robust development and homeostasis throughout the eukaryotic kingdom.

Real-time, label-free, intraoperative visualization of peripheral nerves and micro-vasculatures using multimodal optical imaging techniques

Accurate, real-time identification and display of critical anatomic structures, such as the nerve and vasculature structures, are critical for reducing complications and improving surgical outcomes. Human vision is frequently limited in clearly distinguishing and contrasting these structures. We present a novel imaging system, which enables noninvasive visualization of critical anatomic structures during surgical dissection. Peripheral nerves are visualized by a snapshot polarimetry that calculates the anisotropic optical properties. Vascular structures, both venous and arterial, are identified and monitored in real-time using a near-infrared laser-speckle-contrast imaging. We evaluate the system by performing in vivo animal studies with qualitative comparison by contrast-agent-aided fluorescence imaging.

Multiparametric approach with diffusion-weighted imaging and dynamic contrast-enhanced MRI: a comparison study for differentiating between benign and malignant bone lesions in adults

AIM

To evaluate and compare the diagnostic performance of quantitative parameters derived from diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in differentiating benign and malignant bone tumours.

MATERIALS AND METHODS

Fifty-five patients (age range, 21-82 years; mean age, 55 years) underwent pretreatment MRI. Apparent diffusion coefficient (ADC) values were calculated by DWI. The DCE-MRI data were analysed for the volume transfer constant (K^trans), extravascular extracellular volume fraction (V_e), and volume rate constant (K_ep), and K^trans/ADC ratio. Each parameter's performance was evaluated using the area under the receiver operating characteristic (ROC) curv (AUC), and their AUCs were compared. ROC curves were analysed and each parameter's optimal cut-off value was determined, from which each parameter was evaluated for sensitivity, specificity, accuracy, and positive and negative predictive values. The odds ratio (OR) with 95% confidence interval for detecting malignant bone lesions after adjusting the age factor of each parameter was estimated.

RESULTS

All parameter values (except V_e) were significantly different between benign and malignant bone tumours (p<0.05). The K^trans had a significantly greater AUC than V_e (p=0.03). The K^trans/ADC and K_ep had the best sensitivity (0.917) and specificity (0.632), respectively. The K_ep and K^trans/ADC had the best positive (0.811) and negative (0.769) predictive values, respectively. The OR was highest for K^trans/ADC (17.38; p=0.0013).

CONCLUSION

The K^trans, K_ep, ADC, and K^trans/ADC could help to detect malignant lesions from bone tumours and K^trans/ADC appears to be the superior variable among them.

Fast phase stabilization of a low frequency beat note for atom interferometry

Atom interferometry experiments rely on the ability to obtain a stable signal that corresponds to an atomic phase. For interferometers that use laser beams to manipulate the atoms, noise in the lasers can lead to errors in the atomic measurement. In particular, it is often necessary to actively stabilize the optical phase between two frequency components of the beams. Typically this is achieved using a time-domain measurement of a beat note between the two frequencies. This becomes challenging when the frequency difference is small and the phase measurement must be made quickly. The method presented here instead uses a spatial interference detection to rapidly measure the optical phase for arbitrary frequency differences. A feedback system operating at a bandwidth of about 10 MHz could then correct the phase in about 3 μs. This time is short enough that the phase correction could be applied at the start of a laser pulse without appreciably degrading the fidelity of the atom interferometer operation. The phase stabilization system was demonstrated in a simple atom interferometer measurement of the (87)Rb recoil frequency.

Vitamin D deficiency in Parkinson's disease patients with orthostatic hypotension

OBJECTIVES

The purpose of our study was to investigate the associations between serum vitamin D3 levels and orthostatic hypotension (OH) in patients with Parkinson's disease (PD).

MATERIALS AND METHODS

Fifty-five patients with PD were enrolled in this study. Blood pressure (BP) measurements were gathered while the patients were in the supine position and while standing up. Then, the patients were divided into two groups: PD patients with and without OH. We compared the levels of serum 25-hydroxyvitamin D3 and 1, 25-dihydroxyvitamin D3 (calcitriol) between the two groups.

RESULTS

Serum 25-hydroxyvitamin D and calcitriol levels were significantly decreased in patients with OH compared with those without OH. The systolic and diastolic BPs and symptom severities significantly negatively correlated with the serum 25-hydroxyvitamin D and calcitriol levels.

CONCLUSIONS

Although the underlying mechanism for this association is not fully understood, our results suggest that low vitamin D status is associated with OH in patients with PD.

MicroRNA-155 Reinforces HIV Latency

The presence of a small number of infected but transcriptionally dormant cells currently thwarts a cure for the more than 35 million individuals infected with HIV. Reactivation of these latently infected cells may result in three fates: 1) cell death due to a viral cytopathic effect, 2) cell death due to immune clearance, or 3) a retreat into latency. Uncovering the dynamics of HIV gene expression and silencing in the latent reservoir will be crucial for developing an HIV-1 cure. Here we identify and characterize an intracellular circuit involving TRIM32, an HIV activator, and miR-155, a microRNA that may promote a return to latency in these transiently activated reservoir cells. Notably, we demonstrate that TRIM32, an E3 ubiquitin ligase, promotes reactivation from latency by directly modifying IκBα, leading to a novel mechanism of NF-κB induction not involving IκB kinase activation.

Kinetic enhancement of the diffusion-limited enzyme beta-galactosidase when displayed with quantum dots

Schematic of a tetrameric β-galactosidase enzyme attached to and displaying 625 nm emitting QDs coated with a CL4 ligand via each of the 4 pendent His₆ tags.

Enhanced oxidative damage to DNA, lipids, and proteins and levels of some antioxidant enzymes, cytokines, and heat shock proteins in patients infected with influenza H1N1 virus

Overweight and obesity is becoming widespread enough to generate an acceptable and misleading social status. By 2030, in the USA up to 86 % of adults will be overweight or obese. Some selected statistical data based on the body mass index (BMI) indicated that overweight was not associated with increased mortality, this provoked a conceivable interest. Added to this is the observation that while the prevalence of obesity is dramatically increasing, the cardiovascular mortality and life expectancy in the European Union and USA has improved. When more sensitive indicators of body adiposity and its distribution than the BMI, like the waist-thigh ratio in both sexes and the waist-hip ratio in women are projected on mortality, it becomes obvious that even overweight is associated with an increased health risk. Gaining excessive body fat is a continuous, frequently progressive process. Present obesity epidemic in childhood will manifest with deleterious consequences only in future years when adolescents reach adulthood. Prevention is thus essential even before the overweight sets in. Improved life expectancy observed in large populations despite obesity epidemic, is a favourable medical success in the management of hypertension, of serum lipid disorders and diabetes. While encouraging, when it is observed in large population, it does not take away the potential health risk of a metabolic disorder in an individual who is overweight (Fig. 7, Ref. 25).