Almiramide D, cytotoxic peptide from the marine cyanobacterium Oscillatoria nigroviridis

Marine benthic cyanobacteria are widely known as a source of toxic and potentially useful compounds.These microorganisms have been studied from many Caribbean locations, which recently include locations in the Colombian Caribbean Sea. In the present study, six lipopeptides named almiramides D to H, together with the known almiramide B are identified from a mat characterized as Oscillatoria nigroviridis collected at the Island of Providence (Colombia, S.W. Caribbean Sea). The most abundant compounds, almiramides B and D were characterized by NMR and HRESIMS, while the structures of the minor compounds almiramides E to H were proposed by the analysis of their HRESIMS and MS2 spectra. Almiramides B and D were tested against six human cell lines including a gingival fibroblast cell line and five human tumor cell lines (A549, MDA-MB231, MCF-7, HeLa and PC3) showing a strong but not selective toxicity.

Epi-illumination diffraction phase microscopy with white light

We demonstrate the first reflection-based epi-illumination diffraction phase microscope with white light (epi-wDPM). The epi-wDPM system combines the off-axis, common-path, and white light approaches, in a reflection geometry enabling sub-nanometer spatial and temporal noise levels, while providing single-shot acquisition for opaque samples. We verified the epi-wDPM results by measuring control samples with known dimensions and comparing them to measurements from other well-established techniques. We imaged gold-coated HeLa cells to illustrate the tradeoffs between epi-wDPM with low and high spatial coherence.

Quantitative phase imaging with partially coherent illumination

In this Letter, we formulate a mathematical model for predicting experimental outcomes in quantitative phase imaging (QPI) when the illumination field is partially spatially coherent. We derive formulae that apply to QPI and discuss expected results for two classes of QPI experiments: common path and traditional interferometry, under varying degrees of spatial coherence. In particular, our results describe the physical relationship between the spatial coherence of the illuminating field and the halo effect, which is well known in phase-contrast microscopy. We performed experiments relevant to this common situation and found that our theory is in excellent agreement with the data. With this new understanding of the effects of spatial coherence, our formulae offer an avenue for removing halo artifacts from phase images.

Does Positive Airway Pressure Therapy Result in Improved Sleep Quality?

INTRODUCTION

Positive airway pressure (PAP) therapy is the gold-standard for obstructive sleep apnea (OSA) management. While it is known that PAP is efficacious for controlling breathing events during sleep when it is worn at the right pressure for the amount of time prescribed, there is less clear data on how well it improves sleep quality. There are few studies that have examined the effectiveness of PAP therapy on sleep quality.

METHODS

OSA participants (n = 241) from a larger trial examining a PAP adherence were included. Participants were provided with PAP instruction and followed at 2 months and 4 months. PAP adherence was measured as the number of hours per night at prescribed pressure, an objective measure of treatment adherence. The Pittsburgh Sleep Quality Index (PSQI) was used as the primary measure of sleep quality.

RESULTS

The PSQI was significantly correlated with PAP adherence at both the 2-month and 4-month time points, such that lower sleep quality was associated with lower PAP use. This finding held for the sleep disturbance subscale of the PSQI. Over 55% of those using PAP therapy at the 4-month time point continued to report significantly disturbed sleep.

DISCUSSION

This study shows that PAP therapy does not appear to improve sleep quality to a degree that would be expected. Over half of those patients using PAP therapy still experienced disturbed sleep. Whether the disturbed sleep is directly attributable to the PAP device itself or to disturbed sleep secondary to uncontrolled OSA when PAP is not worn is worthy of further investigation.

What is the risk of having a total hip or knee replacement for patients with lupus?

Individuals with systemic lupus erythematosus (SLE) frequently have arthralgia but joint damage leading to surgery is thought to be less common. In addition to inflammatory damage, other reasons like avascular necrosis (AVN), which is often associated with steroid use, excessive alcohol intake and antiphospholipid syndrome (APS), may increase the likelihood of large joint failure. In this study we aimed to determine the likelihood of having a total hip replacement (THR) or total knee replacement (TKR) for individuals with SLE compared to those without lupus, by performing a retrospective matched case control study of all THRs and TKRs that were performed between 1991 and 2011 and recorded in the General Practice Research Database (GPRD). Individuals with inflammatory arthritis due to any other causes were excluded and the results were adjusted for steroid use, alcohol consumption (drinking status) and APS. The results show that patients with lupus who had a THR or TKR were younger than their peers without lupus. In addition, they appeared to have a significantly increased risk of TKR but the increased risk of THR did not remain after adjustment for steroid use, alcohol consumption and APS.

Relationships among muscle dysmorphia characteristics, body image quality of life, and coping in males

OBJECTIVES

The purpose of this study was to examine relationships among bodybuilding dependence, muscle satisfaction, body image-related quality of life and body image-related coping strategies, and test the hypothesis that muscle dysmorphia characteristics may predict quality of life via coping strategies.

DESIGN

Participants (294 males, Mage=20.5 years, SD=3.1) participated in a cross-sectional survey.

METHODS

Participants completed questionnaires assessing muscle satisfaction, bodybuilding dependence, body image-related quality of life and body image-related coping.

RESULTS

Quality of life was correlated positively with muscle satisfaction and bodybuilding dependence but negatively with body image coping (P<0.05). Body image coping was correlated positively with bodybuilding dependence and negatively with muscle satisfaction (P<0.05). Mediation analysis found that bodybuilding dependence and muscle satisfaction predicted quality of life both directly and indirectly via body image coping strategies (as evidenced by the bias corrected and accelerated bootstrapped confidence intervals).

CONCLUSIONS

These results provide preliminary evidence regarding the ways that muscularity concerns might influence body image-related quality of life.

The costs of late detection of developmental dysplasia of the hip

PURPOSE

Debate currently exists regarding the economic viability for screening for developmental dysplasia of the hip in infants.

METHODS

A prospective study of infant hip dysplasia over the period of 1998-2008 (36,960 live births) was performed to determine treatment complexity and associated costs of disease detection and hospital treatment, related to the age at presentation and treatment modality. The involved screening programme utilised universal clinical screening of all infants and selective ultrasound screening of at-risk infants.

RESULTS

One hundred and seventy-nine infants (4.8/1,000) presented with hip dysplasia. Thirty-four infants presented late (> 3 months of age) and required closed or open reduction. One hundred and forty-five infants presented at < 3 months of age, 14 of whom failed early Pavlik harness treatment. A detailed cost analysis revealed: 131 early presenters with successful management in a Pavlik harness at a cost of £601/child; 34 late presenters who required surgery (36 hips, 19 closed/17 open reductions, one revision procedure) at a cost of £4,352/child; and 14 early presenters with failed management in a Pavlik harness requiring more protracted surgery (18 hips, four closed/14 open reductions, seven revision procedures) at a cost of £7,052/child.

CONCLUSIONS

Late detection causes increased treatment complexity and a sevenfold increase in the short-term costs of treatment, compared to early detection and successful management in a Pavlik harness.

DISCUSSION

Improved strategies are needed for the 10 % of early presenting infants who fail Pavlik harness treatment and require the most complex and costly interventions.