The mitochondrial chaperone TRAP1 regulates F-ATP synthase channel formation

Binding of the mitochondrial chaperone TRAP1 to client proteins shapes bioenergetic and proteostatic adaptations of cells, but the panel of TRAP1 clients is only partially defined. Here we show that TRAP1 interacts with F-ATP synthase, the protein complex that provides most cellular ATP. TRAP1 competes with the peptidyl-prolyl cis-trans isomerase cyclophilin D (CyPD) for binding to the oligomycin sensitivity-conferring protein (OSCP) subunit of F-ATP synthase, increasing its catalytic activity and counteracting the inhibitory effect of CyPD. Electrophysiological measurements indicate that TRAP1 directly inhibits a channel activity of purified F-ATP synthase endowed with the features of the permeability transition pore (PTP) and that it reverses PTP induction by CyPD, antagonizing PTP-dependent mitochondrial depolarization and cell death. Conversely, CyPD outcompetes the TRAP1 inhibitory effect on the channel. Our data identify TRAP1 as an F-ATP synthase regulator that can influence cell bioenergetics and survival and can be targeted in pathological conditions where these processes are dysregulated, such as cancer.

High glucose induces an early and transient cytoprotective autophagy in retinal Müller cells

PURPOSE

We investigated the autophagic response of rat Müller rMC-1 cells during a short-term high glucose challenge.

METHODS

rMC-1 cells were maintained in 5 mM glucose (LG) or exposed to 25 mM glucose (HG). Western blot analysis was used to evaluate the expression levels of markers of autophagy (LC3-II, p62) and glial activation (AQP4), as well as the activation of TRAF2/JNK, ERK and AKT pathways. Autophagic flux assessment was performed using the autophagy inhibitor chloroquine. ROS levels were measured by flow cytometry using dichlorofluorescein diacetate. ERK involvement in autophagy induction was addressed using the ERK inhibitor FR180204. The effect of autophagy inhibition on cell viability was evaluated by SRB assay.

RESULTS

Activation of autophagy was observed in the first 2-6 h of HG exposure. This early autophagic response was transient, not accompanied by an increase in AQP4 or in the phospho-activation of JNK, a key mediator of cellular response to oxidative stress, and required ERK activity. Cells exposed to HG had a lower viability upon autophagy inhibition by chloroquine, as compared to those maintained in LG.

CONCLUSION

A short-term HG challenge triggers in rMC-1 cells a process improving the ability to cope with stressful conditions, which involves ERK and an early and transient autophagy activation.

Outer retina dysfunction and choriocapillaris impairment in type 1 diabetes

To study the outer retina morpho-functional characteristics and the choriocapillaris (CC) features in type 1 diabetic (T1D) patients, with and without signs of diabetic retinopathy (NPDR and NoDR). Twenty-five NPDR and 18 NoDR eyes were imaged by Optical Coherence Tomography Angiography. Ellipsoid zone (EZ) “normalized” reflectivity and CC perfusion density parameters, as flow deficits number (FDn), flow deficit average area (FDa) and flow deficit percentage (FD%), were analysed. Multifocal electroretinogram (mfERG) response amplitude densities (RADs) were measured. Mean EZ “normalized” reflectivity, CC FDn and FD% values, were similar (p > 0.05) in both groups, FDa was significant greater (p > 0.05) in NPDR compared with NoDR eyes. MfERG-RADs were similar in both groups. NPDR eyes showed a significant (p < 0.05) linear correlation between RADs and both, CC FDa and FD%. The EZ “normalized” reflectivity was negatively correlated with CC FD% in NoDR eyes. In NPDR T1D eyes a significant relationship between abnormal outer retina functional responses and CC impairment was observed, while in NoDR eyes the photoreceptor reflectivity was correlated to CC abnormalities. The outer retina dysfunction in NPDR correlated to CC drop-out let hypothesize that the outer retinal elements are functionally impaired in proportion to the CC vascular supply deficit.

Secretome Analysis of Hypoxia-Induced 3T3-L1 Adipocytes Uncovers Novel Proteins Potentially Involved in Obesity

In the obese state, as adipose tissue expands, adipocytes become hypoxic and dysfunctional, leading to changes in the pattern of adipocyte-secreted proteins. To better understand the role of hypoxia in the mechanisms linked to obesity, we comparatively analyzed the secretome of murine differentiated 3T3-L1 adipocytes exposed to normoxia or hypoxia for 24 h. Proteins secreted into the culture media were precipitated by trichloroacetic acid and then digested with trypsin. The peptides were labeled with dimethyl labeling and analyzed by reversed phase nanoscale liquid chromatography coupled to a quadrupole Orbitrap mass spectrometer. From a total of 1508 identified proteins, 109 were differentially regulated, of which 108 were genuinely secreted. Factors significantly downregulated in hypoxic conditions included adiponectin, a known adipokine implicated in metabolic processes, as well as thrombospondin-1 and -2, and matrix metalloproteinase-11, all multifunctional proteins involved in extracellular matrix (ECM) homeostasis. Findings were validated by Western blot analysis. Expression studies of the relative genes were performed in parallel experiments in vitro, in differentiated 3T3-L1 adipocytes, and in vivo, in fat tissues from obese versus lean mice. Our observations are compatible with the concept that hypoxia may be an early trigger for both adipose cell dysfunction and ECM remodeling.

Temperature-dependent regulation of the Ochrobactrum anthropi proteome

Ochrobactrum anthropi is a Gram-negative rod belonging to the Brucellaceae family, able to colonize a variety of environments, and actually reported as a human opportunistic pathogen. Despite its low virulence, the bacterium causes a growing number of hospital-acquired infections mainly, but not exclusively, in immunocompromised patients. The aim of this study was to obtain an overview of the global proteome changes occurring in O. anthropi in response to different growth temperatures, in order to achieve a major understanding of the mechanisms by which the bacterium adapts to different habitats and to identify some potential virulence factors. Combined quantitative mass spectrometry-based proteomics and bioinformatics approaches were carried out on two O. anthropi strains grown at temperatures miming soil/plants habitat (25°C) and human host environment (37°C), respectively. Proteomic analysis led to the identification of over 150 differentially expressed proteins in both strains, out of over 1200 total protein identifications. Among them, proteins responsible for heat shock response (DnaK, GrpE), motility (FliC, FlgG, FlgE), and putative virulence factors (TolB) were identified. The study represents the first quantitative proteomic analysis of O. anthropi performed by high-resolution quantitative mass spectrometry.

Proteomic analysis of protein purified derivative of Mycobacterium bovis

Background

Tuberculin skin test based on in vivo intradermal inoculation of purified protein derivative from Mycobacterium bovis (bPPD) is the diagnostic test for the control and surveillance of bovine tuberculosis (bTB).

Methods

Proteomic analysis was performed on different bPPD preparations from M. bovis, strain AN5. Proteins were precipitated from bPPD solutions by TCA precipitation. The proteome of bPPD preparations was investigated by bottom-up proteomics, which consisted in protein digestion and nano-LC–MS/MS analysis. Mass spectrometry analysis was performed on a Q-exactive hybrid quadrupole-Orbitrap mass spectrometer coupled online to an Easy nano-LC1000 system.

Results

Three hundred and fifty-six proteins were identified and quantified by at least 2 peptides (99% confidence per peptide). One hundred and ninety-eight proteins, which had not been previously described, were detected; furthermore, the proteomic profile shared 80 proteins with previous proteomes from bPPDs from the United Kingdom and Brazil and 139 protein components from bPPD from Korea. Locus name of M. bovis (Mb) with orthologs from M. tuberculosis H37Rv, comparative gene and protein length, molecular mass, functional categories, gene name and function of each protein were reported. Ninety-two T cell mycobacterial antigens responsible for delayed-type hypersensitivity were detected, fifty-two of which were not previously reported in any bPPD proteome. Data are available via ProteomeXchange with identifier PXD005920.

Conclusions

This study represents the highest proteome coverage of bPPD preparations to date. Since proteins perform cellular functions essential to health and/or disease, obtaining knowledge of their presence and variance is of great importance in understanding disease states and for advancing translational studies. Therefore, to better understand Mycobacterium tuberculosis complex biology during infection, survival, and persistence, the reproducible evaluation of the proteins that catalyze and control these processes is critically important. More active and more specific tuberculins would be desirable. Indeed, many antigens contained within bPPD are currently responsible for the cross-reactivity resulting in false-positive results as they are shared between non-tuberculous and tuberculous mycobacteria.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-017-1172-1) contains supplementary material, which is available to authorized users.

Aflibercept in persistent neovascular AMD: comparison of different treatment strategies in switching therapy

PurposeTo evaluate the effects of aflibercept administered according to a pro re nata (PRN) or Fixed Regimen to patients with neovascular AMD and persistent intraretinal/subretinal fluid (IRF/SRF) despite three consecutive ranibizumab injections.MethodsPatients were switched to aflibercept injection (IVA) administered according to a PRN or to a fixed regimen for 1 year in two different retina centers. At baseline each patient underwent a complete ophthalmologic evaluation, including best-corrected visual acuity assessment (BCVA ETDRS chart), fluorescein, and indocyanine green angiography and OCT.ResultsEach group included 36 eyes. After 1 year the PRN group showed BCVA stabilization (63 vs 60 letters, P=0.33), whereas fixed regimen group showed significant BCVA improvement (68 vs 71, P=0.008). The median central retinal thickness decreased by 94 μm in the PRN (P=0.002) and by 148 μm in the fixed regimen group (P≤0.001). Complete IRF/SRF reabsorption was found in 58% of eyes in the PRN and in 42% of eyes in the fixed regimen group. At 1-year visit, the percentage of eyes with pigment epithelium detachment did not significantly decrease, but a height reduction was recorded in both groups. The median number of IVA was 3.5 in the PRN and 7 in the fixed regimen group.ConclusionThe switch to aflibercept with both treatment strategies enabled improvement in morphological parameters and stabilization of visual acuity. BCVA improvement and reduction in vision loss with reduction in retinal thickness, fluid and PED height was achieved with the fixed regimen in previously treated nAMD after 1 year.

Serotonin syndrome caused by olanzapine and clomipramine

We describe a case of severe serotonin syndrome. The patient was simultaneously taking the atypical antidepressant olanzapine and a tricyclical antidepressant, clomipramine. Symptoms included altered mental state resulting in coma, myoclonus, hyperreflexia, diaphoresis, diarrhoea, disorientation and fever. After suspension of antidepressant drugs, intensive symptomatic treatment and administration of biperiden and cyproheptadine, the patient's condition improved.

Photodynamic therapy outcomes in a case of macular choroidal neovascularization secondary to Candida endophthalmitis

PURPOSE

To evaluate the effects on visual function and choroidal neovascularization (CNV) progression in a case of subretinal CNV due to Candida endophthalmitis treated with a combination of photodynamic therapy (PDT) and drugs.

METHODS

A 28-year-old one-eyed woman with CNV in the right eye came to our observation. The CNV developed as a consequence of Candida endophthalmitis. The CNV was treated with six PDT treatments with verteporfin in association with systemic steroid therapy with prednisone (100 mg/day to reduce) and fluconazole (800 mg/day to reduce). Visual acuity (VA) was assessed in pre-PDT conditions and after six PDT treatments (24 months of follow-up).

RESULTS

Pre-PDT VA was 20/125; after 24 months of follow-up, six PDT re-treatments, and pharmacologic therapy, VA was stabilized at 20/100.

CONCLUSIONS

In our case, associated PDT and drug therapies were safe and useful to maintain VA and to arrest CNV progression in the foveal region after 2 years of follow-up.

Quality of vision: A consensus building initiative for a new ophthalmologic concept

PURPOSE

Many studies have addressed the quantification of visual acuity, and the conventional method of measuring it has so far demonstrated serious limitations. Vision testing requires new methods that can more precisely express the quality of vision as perceived by the patient.

METHODS

This study employed the Delphi method of consensus building. Concepts associated with quality of vision (QoV) were identified by a board of experts and proposed to participating specialists in two subsequent questionnaires. Upon receipt of the completed questionnaires, the replies were classified to determine the building blocks of a consensus.

RESULTS

By analyzing the replies to the two questionnaires, the authors determined the key elements of QoV on which a consensus was found among the respondents.

CONCLUSIONS

A consensus was reached on the opinion that the quantification of visual acuity by traditional means is inadequate for investigating QoV. Although visual acuity is still a basic element for testing, the experts believe that contrast sensitivity, reading speed, and microperimetry are additional parameters necessary for quantifying QoV. The use of a psychometric questionnaire on visual function could allow a better interpretation of visual impairment.

Use of recombinant activated factor VII in a case of severe postpartum haemorrhage

We describe the case of a 24 year old woman, affected by haemorrhagic shock due to post-partum uterine atony, who underwent an emergency hysterectomy with persistent postoperative bleeding, successfully treated with recombinant activated factor VII (Novoseven).

Use of activated protein C in a case of paediatric septic shock

We describe a clinical case of a 7 year old girl, affected by peritonitis, septic shock and multiorgan failure, treated successfully with drotrecogin alpha associated with conventional therapy.

Visual acuity and macular sensitivity in myopic eyes before and after laser in situ keratomileusis

PURPOSE

To evaluate the changes in visual acuity (VA) and in macular sensitivity in myopic eyes subjected to laser in situ keratomileusis (LASIK) refractive surgery.

METHODS

In 38 myopic eyes, VA by Snellen's table and macular sensitivity by scanning laser ophthalmoscope (SLO) microperimetry were assessed before and after 24 weeks after LASIK surgery. The myopic eyes were divided into three age-matched groups: Group A = from -5 diopters (D) to -7 D and normal SLO-macular sensitivity (15 eyes); Group B = from -8 D to -16 D and normal SLO-macular sensitivity (9 eyes); and Group C = from -8 D to -16 D and abnormal SLO-macular sensitivity.

RESULTS

Group A and B eyes, at the first week after LASIK surgery, we observed a significant analysis of variance, p<0.01) reduction in VA and SLO-macular sensitivity with respect to baseline values, while after 12 and 24 weeks no differences (p>0.01) were found when compared to baseline. In Group C patients, at 1 and 4 weeks after surgical treatment, we observed a significant (p<0.01) reduction in VA and SLO-macular sensitivity with respect to baseline values. At 12 and 24 weeks the values of VA were reduced, but not significantly (p>0.01), while values of SLO-macular sensitivity were still significantly (p<0.01) reduced.

CONCLUSIONS

LASIK could induce a reduction in VA and SLO-macular sensitivity in all myopic eyes during the 4 weeks following the surgery. This reduction is still present after 24 weeks only in eyes with the highest preoperative degree of myopia combined with the greatest reduction in macular sensitivity.

[Pharmacological sympathetic block in complex regional pain syndrome]

PURPOSE

The Complex Regional Pain Syndrome (CRPS) is a chronic pain state provoked by lesions of the soft tissues or of the bony tissues (type CRPS-I or reflex sympathetic dystrophy-RSD) or by lesions of the nerves (type CRPS-II or causalgia) with vegetative alterations (perspiration, vasomotory alterations) and trophic alterations (bony cutaneous atrophy, alopecia, articular contractures). The pharmacological block of the sympathetic nerves through a peripheral vein is inserted in the multidisciplinary approach that characterizes the therapy of this syndrome.

MATERIALS AND METHODS

A retrospective survey was carried out on a group of 185 patients affected by RDS/CRPS with block of the sympathetic nerves through a peripheral vein with guanethidine. Superior limb: Inflation of the tourniquet till disappearance of the radial wrist. Cannulation of a peripheral vein with Butterfly needle n. 23. Guanethidine 10 mg, lidocaine 20 mg, sodic heparin 500 u.i, NaCl 0.9% 20 ml. Injection in 5 minutes. Permanence of the pneumatic tourniquet inflated above systolic blood pressure for 15 minutes. Deflation slowly. Inferior limb: Inflation of the tourniquet till disappearance of the pedidium wrist. Cannulation of a peripheral vein with Butterfly needle n. 23. Guanethidine 20 mg, lidocaine 40 mg, sodic heparin 1000 u.i, NaCl 0.9% 40 ml. Injection in 5 minutes. Permanence of the pneumatic tourniquet inflated above systolic blood pressure for 15 minutes. Deflation slowly.

RESULTS

The first stage (hyperemic) showed the highest incidence of remissions: (83, 33%). Even in the second stage (dystrophic) the answer to the therapy has been fundamentally positive: (53, 68%). In the third stage (atrophic) the results have been more modest: (8, 33%).

CONCLUSIONS

The block of sympathetic system with guanethidine is still an important method in the therapy of the CRPS; in fact it is surely less invading than the blocks of the stellate ganglion or of the lumbar sympathetic.

Scanning laser ophthalmoscope microperimetry

In this article, the methodologies and clinical applications of microperimetry performed by scanning laser ophthalmoscope (SLO) are described. This technique provides functional results by direct visualization of the macular area. We present the most interesting data about clinical applications in ocular pathology. SLO microperimetry is a new diagnostic tool in ophthalmic practice. It permits an exact, point-to-point correspondence between fundus image and perimetric results, impossible to achieve by projection perimetry, so representing the most suitable device for simultaneous fundus imaging and psychophysical testing. Microperimetry is performed by SLO (Rodenstock),1 which permits other applications. SLO microperimetry allows the real-time functional study of retinal sensitivity by direct ophthalmoscopic control of the retinal surface. Foveal or excentric fixation can be assessed as well. Instability of fixation during computerized perimetry is a possible misleading factor resulting in unexplainable findings, especially in eyes with decreased visual acuity. The main characteristic of microperimetry is the ability to see the stimuli presented on the retina in real time: this permits an accurate monitoring of fixation and correlation of anatomical or pathological features directly with retinal function.

Scanning laser ophthalmoscopy in the early diagnosis of vitreoretinal interface syndrome

BACKGROUND

The purpose of this study was to estimate if and to what extent scanning laser ophthalmoscopy can help in the early diagnosis and follow-up management of the vitreoretinal interface syndrome, which includes disorders such as cellophane maculopathy, pseudomacular hole, macular pucker, and macular hole.

METHODS

The 35 fellow eyes of 35 patients with vitreoretinal interface syndromes in the first eye underwent scanning laser ophthalmoscopy microperimetry and argon, helium-neon, and infrared scanning laser ophthalmoscopy. Fellow eyes were defined as clinically positive or negative for vitreoretinal interface syndrome. Fellow eyes then were classified based on scanning laser ophthalmoscopy techniques. Patients were observed for an average of 18 months (range, 10-26 months).

RESULTS

Thirty-two of the 35 fellow eyes were classified as clinically negative, and three of the 35 were classified as clinically positive. Fifteen of the 32 clinically negative fellow eyes were redefined as positive on scanning laser ophthalmoscopy. None of the clinically positive eyes proved to be negative on scanning laser ophthalmoscopy. During the average follow-up period (18 months), the condition of five of 18 fellow eyes that were positive on scanning laser ophthalmoscopy worsened. None of the 17 eyes that were negative on scanning laser ophthalmoscopy worsened.

CONCLUSION

Scanning laser ophthalmoscopy can produce beautifully clear images of structures that are otherwise difficult to see and document, such as posterior hyaloid and the inner retinal layers. Despite a relatively limited number of cases and the short duration of the follow-up period, the present study suggests that scanning laser ophthalmoscopy has good sensitivity and specificity for the early diagnosis of vitreoretinal interface syndromes.

Randomized clinical trial of tamoxifen plus sequential CMF chemotherapy versus tamoxifen alone in postmenopausal women with advanced breast cancer

Eighty-eight postmenopausal women with metastatic breast cancer, in whom estrogen receptors (ER) were positive or unknown, were treated on a controlled trial to determine the effectiveness of tamoxifen and to assess the therapeutic advantage of sequentially adding low-dose cyclophosphamide-methotrexate-5-fluorouracil (CMF) chemotherapy in tamoxifen responders. Patients with known ER negative status were not studied. After the initial 12-week treatment with tamoxifen alone, 60% of ER positive patients achieved complete or partial response as did 35% in whom ER were unknown. Response status further improved in 18% randomized to continue tamoxifen alone vs 31% in whom CMF was added to tamoxifen. There were no statistically significant differences in time to the development of progressive disease or survival between the ER positive and ER unknown patients or between the tamoxifen and tamoxifen plus CMF groups. We conclude that inability to determine ER status should not prejudice against the use of tamoxifen in postmenopausal patients with advanced breast cancer. No benefit has been demonstrated from the addition of CMF chemotherapy in tamoxifen responders.

Tamoxifen plus sequential CMF chemotherapy versus tamoxifen alone in postmenopausal patients with advanced breast cancer: a randomized trial

Eighty-nine postmenopausal women with metastatic breast cancer, in whom estrogen receptors (ER) were positive or unknown, were treated on a controlled trial to determine the effectiveness of tamoxifen and to assess the therapeutic advantage of sequentially adding low-dose cyclophosphamide-methotrexate-5-fluorouracil (CMF) chemotherapy in tamoxifen responders. Patients with known ER negative status were not studied. After the initial 12 week treatment with tamoxifen alone, 59% of ER positive patients achieved complete or partial response as did 35% in whom ER were unknown. Response status further improved in 18% randomized to continue tamoxifen alone vs. 28% in whom CMF was added to tamoxifen. There were no statistically significant differences in time to the development of progressive disease or survival between the ER positive and ER unknown patients or between the tamoxifen and tamoxifen plus CMF groups. We conclude that inability to determine ER status should not prejudice against the use of tamoxifen in postmenopausal patients with advanced breast cancer. As yet, no benefit has been demonstrated from the addition of CMF chemotherapy in tamoxifen responders.