Alterations in Plasma Lipid Profiles Associated with Melanoma and Therapy Resistance

Dysfunctions of lipid metabolism are associated with tumor progression and treatment resistance of cutaneous melanoma. BRAF/MEK inhibitor resistance is linked to alterations of melanoma lipid pathways. We evaluated whether a specific lipid pattern characterizes plasma from melanoma patients and their response to therapy. Plasma samples from patients and controls were analyzed for FASN and DHCR24 levels and lipidomic profiles. FASN and DHCR24 expression resulted in association with disease condition and related to plasma cholesterol and triglycerides in patients at different disease stages (n = 144) as compared to controls (n = 115). Untargeted lipidomics in plasma (n = 40) from advanced disease patients and controls revealed altered levels of different lipids, including fatty acid derivatives and sphingolipids. Targeted lipidomics identified higher levels of dihydroceramides, ceramides, sphingomyelins, ganglioside GM3, sphingosine, sphingosine-1-phosphate, and dihydrosphingosine, saturated and unsaturated fatty acids. When melanoma patients were stratified based on a long/short-term clinical response to kinase inhibitors, differences in plasma levels were shown for saturated fatty acids (FA 16:0, FA18:0) and oleic acid (FA18:1). Our results associated altered levels of selected lipid species in plasma of melanoma patients with a more favorable prognosis. Although obtained in a small cohort, these results pave the way to lipidomic profiling for melanoma patient stratification.

Observing Etna volcano dynamics through seismic and deformation patterns

Geophysical data provide the chance to investigate a volcano's dynamics; considerable information can especially be gleaned on the stress and strain patterns accompanying the internal processes and the effect of magma ascent on the main structures triggering earthquakes. Here, we analysed in detail the seismicity recorded over the last two decades on Etna volcano (southern Italy), focusing on earthquakes distribution and focal mechanism clustering; the ground deformation pattern affecting the volcanic edifice with the inflation and deflation phases was also examined. Analysed data were compared in order to shed light on possible relationships with the volcanic activity and to better understand the internal dynamics of the volcano over time. Significant steps during or shortly before major eruptions in the seismic strain release and ground deformation temporal series highlight a straightforward relationship between seismicity occurring at shallow level, inflation/deflation and volcanism. Furthermore, at depths greater than 5-7 km, down to about 20 km, the orientation of the P- and T-axes clearly indicate the existence of a pressure source in the central part of the volcano. All the results underline that the stress field related to the volcano plumbing system interferes with the regional field, partly overriding it.

New insights on the active degassing system of the Lipari–Vulcano complex (South Italy) inferred from Local Earthquake Tomography

Seismic tomography is a very powerful and effective approach to look at depths beneath volcanic systems thus helping to better understand their behaviour. The P-wave and S-wave velocity ratio, in particular, is a key parameter useful to discriminate the presence of gas, fluids and melts. We computed the first 3-D overall model of Vp, Vs and Vp/Vs for the Lipari–Vulcano complex, central sector of the Aeolian volcanic archipelago (southern Italy). The investigated area has been characterized in recent times by fumaroles, hydrothermal activity and active degassing. In particular, in the Vulcano Island, several episodes of anomalous increases of fumarole temperature and strong degassing have been recorded in the past decades and the last “crisis”, started in September 2021, is still ongoing. For tomographic inversion we collected ~ 4400 crustal earthquakes that occurred in the last thirty years and we used the LOcal TOmography Software LOTOS. The results clearly depicted two low Vp and Vp/Vs anomalies located up to ~ 8 km depths below Vulcano and the western offshore of Lipari, respectively. These anomalies can be associated to the large presence of gas and they furnish a first picture of the gas-filled volumes feeding the main degassing activity of the area.

Targeting of the Lipid Metabolism Impairs Resistance to BRAF Kinase Inhibitor in Melanoma

Drug resistance limits the achievement of persistent cures for the treatment of melanoma, in spite of the efficacy of the available drugs. The aim of the present study was to explore the involvement of lipid metabolism in melanoma resistance and assess the effects of its targeting in cellular models of melanoma with acquired resistance to the BRAF-inhibitor PLX4032/Vemurafenib. Since transcriptional profiles pointed to decreased cholesterol and fatty acids synthesis in resistant cells as compared to their parental counterparts, we examined lipid composition profiles of resistant cells, studied cell growth dependence on extracellular lipids, assessed the modulation of enzymes controlling the main nodes in lipid biosynthesis, and evaluated the effects of targeting Acetyl-CoA Acetyltransferase 2 (ACAT2), the first enzyme in the cholesterol synthesis pathway, and Acyl-CoA Cholesterol Acyl Transferase (ACAT/SOAT), which catalyzes the intracellular esterification of cholesterol and the formation of cholesteryl esters. We found a different lipid composition in the resistant cells, which displayed reduced saturated fatty acids (SFA), increased monounsaturated (MUFA) and polyunsaturated (PUFA), and reduced cholesteryl esters (CE) and triglycerides (TG), along with modulated expression of enzymes regulating biosynthetic nodes of the lipid metabolism. The effect of tackling lipid metabolism pathways in resistant cells was evidenced by lipid starvation, which reduced cell growth, increased sensitivity to the BRAF-inhibitor PLX4032, and induced the expression of enzymes involved in fatty acid and cholesterol metabolism. Molecular targeting of ACAT2 or pharmacological inhibition of SOAT by avasimibe showed antiproliferative effects in melanoma cell lines and a synergistic drug interaction with PLX4032, an effect associated to increased ferroptosis. Overall, our findings reveal that lipid metabolism affects melanoma sensitivity to BRAF inhibitors and that extracellular lipid availability may influence tumor cell response to treatment, a relevant finding in the frame of personalized therapy. In addition, our results indicate new candidate targets for drug combination treatments.

Depression, apathy and impaired self-awareness following severe traumatic brain injury: a preliminary investigation

Primary Objective: The primary aim of this study was to determine the frequency of severe impaired self-awareness (ISA) in patients with severe traumatic brain injury (TBI) and the correlates of selected clinical, neuropsychiatric and cognitive variables. The secondary aim of the study was to assess depression and apathy on the basis of their level of self-awareness. Methods: Thirty patients with severe TBI and 30 demographically matched healthy control subjects (HCs) were compared on measures of ISA, depression, anxiety, alexithymia, neuropsychiatric symptoms and cognitive flexibility. Results: Twenty percent of the patients demonstrated severe ISA. Severe post-acute ISA was associated with more severe cognitive inflexibility, despite the absence of differences in TBI severity, as evidenced by a Glasgow Coma Scale (GCS) score lower than 9 in all cases in the acute phase. Patients with severe ISA showed lower levels of depression and anxiety but tended to show more apathy and to have greater difficulty describing their emotional state than patients with severe TBI who showed minimal or no disturbance in self-awareness. Conclusion: These findings support the general hypothesis that severe ISA following severe TBI is typically not associated with depression and anxiety, but rather with apathy and cognitive inflexibility.

Anca in Dialysis Patients: A Role for Bioincompatibility?

Background

Anti-neutrophil cytoplasmic autoantibodies (ANCA) have been described in patients suffering from systemic vasculitis such as Wegener granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and other pathological conditions. In this paper we report a greater incidence of ANCA in hemodialysis patients as compared to peritoneal dialysis patients, predialytic uremic patients and non-renal patients; a possible role for dialysis bioincompatibility in ANCA generation was also investigated.

Methods

A total of 335 uremics in substitutive treatment (176 in hemodialytic treatment and 159 in peritoneal dialysis) were examined for ANCA positivity. A total of 189 patients with advanced renal failure in conservative treatment and 100 healthy subjects were used as control. The dialysis techniques were standard hemodialysis (n = 119), low volume hemodiafiltration (n = 26) and hemofiltration (n = 31). ANCA positivity was examined by immunofluorescence (IF): diffuse finely granular staining was considered as classical positive reaction (C-ANCA) and P-ANCA was diagnosed if a perinuclear staining was observed. EIA for proteinase-3 (anti PR-3) and myeloperoxidase-antibodies (anti-MPO) were also performed.

Results

In non-renal patients and in patients with pre-dialytic renal insufficiency none were found ANCA positive. In peritoneal dialysis patients all but one were ANCA negative with IF, with all EIA test resulting negative. In hemodialytic patients, a positive IF test was found in 26 (14.7%) for P-ANCA and in 5 (2.8%) for C-ANCA; using the EIA test 23 (13%) patients were positive for MPO and 12 (6.8%) for PR-3.

Conclusions

No correlation with age, primary renal diseases, dialytic age, dialysis membrane materials was found; regarding the different extracorporeal dialytic techniques a higher incidence (p < 0.02) was detected in patients undergoing HDF. Backfiltration of contaminated dialysate may induce ANCA via an increased cytokine generation. (Int J Artif Organs 2000; 23: 97–103)

Is the patient able to watch TV or read the newspaper? A functional semi-structured scale to observe Hemineglect symptoms in Activities of Daily Living (H-ADL)

We developed a functional semi-structured scale to observe Hemineglect symptoms in Activities of Daily Living (H-ADL). The scale could assist clinicians in assessing rehabilitation priorities aimed at correcting any persisting errors or omissions. In addition, the scale could also be used by caregivers to observe patients' progress and improve their participation. Two groups of right brain-damaged patients (25 with hemineglect; 27 without hemineglect) were tested twice: at admission and before discharge from hospital. A control group of healthy individuals matched to patients for age and education and patients' caregivers also participated. Two raters (A; B), experts in neuropsychology, observed patients and healthy individuals using the H-ADL. We found that the H-ADL final scores correlated with the standard hemineglect tests. The three groups differed in performance and differences also emerged between the first and the second assessment, suggesting an improvement due to the remission of hemineglect as a consequence of the treatment. Raters A and B did not differ in their observations, but there were some discrepancies with caregivers' observations. Therefore, although caregivers could help clinicians in detecting persistent hemineglect behaviour, the assessment should be performed by experts in neuropsychology.

Use of chronic sacral nerve stimulation in neurological voiding disorders

AIM

Neurogenic low urinary tract dysfunctions unresponsive to medical and conservative therapy are difficult to manage. Nowadays they can be treated with Sacral Nerve Stimulation (SNS), even if clinical experiences reported in literature are still limited.

METHODS

We performed SNS in 6 patients with neurogenic bladder: 3 patients had incontinence-urgency (1 myelitis, 1 multiple sclerosis, 1 autonomic polineuropathy) and 3 patients had urinary retention (1 incomplete spinal cord lesion, 1 operation for discal hernia T5-T6, 1 hysterectomy).

RESULTS

Among cases with incontinence-urgency we achieved complete control of the bladder in 2 patients while in 1 patient the number of urinary losses was reduced of the 80%. In 2 patients with urinary retention we obtained complete recovery of the bladder function, while in 1 patient the number of cateterisms/die reduced of 50%, the urinary volume for micturion increased and residual urinary volume decreased. Results were unchanged during the follow-up (maximum 26 months), except for 1 patient in which a partial loss of effectiveness occurred.

CONCLUSIONS

Chronic electric stimulation of S3 sacral roots via an implanted neuroprotesis is therefore an effectiveness, save and promising therapeutic option in treatment of neurogenic bladder dysfunctions.

[An unexpected bottleneck]

This is a clinical case concerning an uremic female patient who presented with an important oedema in the omolateral left arm, after the creation of an AV fistula. All the diagnostic procedures including the ultrasound color-Doppler were irrelevant. The patient was positive for a subclavian venous stenosis which was completely unexpected. This clinical case questions how useful it is in indirectly evaluating flow meters by ultrasound color-Doppler in the work-up of central venous steno-occlusions.

[Histopathologic examination of the intervertebral lumbar disk. Evaluation of its usefulness and limitations]

A retrospective clinical-pathological review of 192 lumbar intervertebral discs removed via an interlaminar approach or percutaneous nucleotomy from patients suffering from sciatic pain was carried out in order to assess if routine examination is useful. Only for a case of our series, which showed ill defined features at preoperative neuroradiologic imaging, an intraoperative pathologic examination was necessary. Immunohistochemical study was never required. A routine examination with a hematoxilin-eosin stain was sufficient also to recognize postoperative scar in patients reoperated. In conclusion we think that routine examination of the intervertebral disc is a procedure which is not expensive and useful to assess the nature of the lesion in reoperated patients and in rare cases showing unclear radiologic pattern.

ANCA in dialysis patients: a role for bioincompatibility?

BACKGROUND. Anti-neutrophil cytoplasmic autoantibodies (ANCA) have been described in patients suffering from systemic vasculitis such as Wegener granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and other pathological conditions. In this paper we report a greater incidence of ANCA in hemodialysis patients as compared to peritoneal dialysis patients, pre-dialytic uremic patients and non-renal patients; a possible role for dialysis bioincompatibility in ANCA generation was also investigated.

METHODS

A total of 335 uremics in substitutive treatment (176 in hemodialytic treatment and 159 in peritoneal dialysis) were examined for ANCA positivity. A total of 189 patients with advanced renal failure in conservative treatment and 100 healthy subjects were used as control. The dialysis techniques were standard hemodialysis (n = 119), low volume hemodiafiltration (n = 26) and hemofiltration (n = 31). ANCA positivity was examined by immunofluorescence (IF): diffuse finely granular staining was considered as classical positive reaction (C-ANCA) and P-ANCA was diagnosed if a perinuclear staining was observed. EIA for proteinase-3 (anti PR-3) and myeloperoxidase-antibodies (anti-MPO) were also performed.

RESULTS

In non-renal patients and in patients with pre-dialytic renal insufficiency none were found ANCA positive. In peritoneal dialysis patients all but one were ANCA negative with IF, with all EIA test resulting negative. In hemodialytic patients, a positive IF test was found in 26 (14.7%) for P-ANCA and in 5 (2.8%) for C-ANCA; using the EIA test 23 (13%) patients were positive for MPO and 12 (6.8%) for PR-3.

CONCLUSIONS

No correlation with age, primary renal diseases, dialytic age, dialysis membrane materials was found; regarding the different extracorporeal dialytic techniques a higher incidence (p < 0.02) was detected in patients undergoing HDF Backfiltration of contaminated dialysate may induce ANCA via an increased cytokine generation.

[Adhesion molecules. Current aspects and clinical and therapeutic perspectives]

The study about the adhesion molecules pointed out their pathogenetic role in a lot of diseases within cardiological, nephrological, oncological precincts and in a lot of infectious diseases. Their role was in fact pointed out in the ischemic heart disease and in the reperfusion damage, in the glomerulonephritis, in the tumoural metastatic processes, in the infectious and inflammatory chronic processes. The Authors considered the recent literature and emphasized the therapeutic possibilities that such an experimental approach seems to suggest.

Dipsogenic factors operating in chronic uremics on maintenance hemodialysis

Thirst and hyperdipsia of anuric chronic uremics on maintenance hemodialysis and the possible dipsogenic factors were studied. Exaggerated thirst was present in 213 (86%) of the 247 studied patients. It usually started 4-6 h after the end of the dialysis session, persisted during the whole interdialytic period and often disappeared during the subsequent dialysis. Hyperdipsia, as indicated by the high body weight gain (> 4%) in the interdialytic periods, was present in 33.6% of patients. The highest rate of increase of body weight occurred in the first hours following the end of dialysis sessions. Hypernatremia, potassium depletion, increasing plasma urea levels and elevated plasma angiotensin II levels were considered as the possible dipsogenic factors of a nonpsychic nature. Sodium is certainly of paramount importance for its obliged extracellular position, and when sodium intake is elevated, hypernatremia is very likely the cause of exaggerated thirst and weight gain in patients on hemodialysis. Potassium depletion may cause thirst in animals, but this condition is extremely rare in patients on maintenance hemodialysis, who often accumulate it. In these patients it is, therefore, unlikely that potassium depletion is a dipsogenic factor. Increasing serum urea levels exert an evident dipsogenic effect in anephric rats and urea, when infused into normal volunteers, stimulates thirst. The extracellular urea levels in the interdialytic period are certainly higher than the intracellular ones, as a consequence of its continuous accumulation, and this creates an osmotic gradient with a dipsogenic effect. When this gradient is reversed, following hemodialysis (which removes first the extracellular urea), the dipsogenic effect disappears.(ABSTRACT TRUNCATED AT 250 WORDS)

Synthesis of fast myosin induced by fast ectopic innervation of rat soleus muscle is restricted to the ectopic endplate region

Skeletal muscle fibres, long multinucleated cells, arise by fusion of mononucleated myoblasts to form a myotube that matures into the adult fibre. The two major types of mature fibre, fast and slow fibres, differ physiologically in their rate of isotonic shortening. At the molecular level these type-specific physiological properties are ascribed to different isoforms of myosin, a major protein involved in shortening. Differentiation of fast and slow fibres seems to be under the control of motoneurones, and mature fibres are innervated by only one motoneurone. When rat soleus muscle (SOL, a slow muscle) is dually innervated with a fast nerve, it acquires some properties of a fast muscle, that is, low sensitivity to caffeine and high glycogen content. We report here that in dually innervated soleus muscle the foreign fast nerve induces synthesis of fast isoforms of myosin, but only in the segment of the muscle fibre that is close to the foreign endplate. The localized influence of the nerve endplates suggest that factors controlling the phenotypic expression of the muscle fibre have a short range of activity.

The fate of newly formed satellite cells during compensatory muscle hypertrophy

Compensatory hypertrophy was induced in the rat extensor digitorum longus muscle by extirpation of the synergistic tibialis anterior. Injections of 3H-thymidine (2 muCi/g body weight) was given at 24, 48, and 72 h after the operation. In animals killed immediately after the last injection both satellite cell nuclei and true muscle nuclei were labeled, whereas in animals killed 4 weeks later only true muscle nuclei were labeled. The results are interpreted as indicating incorporation of newly formed satellite cells into the fibers during compensatory hypertrophy.

On the differential response of sarcoplasm and myoplasm to denervation in frog muscle

Electron microscopic evidence is presented that the early response to denervation ("simple atrophy") of the semitendinosus m. of the frog is characterized by a greater prominence of the sarcoplasmic reticulum and by the presence, in the interfibrillar spaces, of mitochondria which are more numerous and smaller than in normal muscle. In contrast with the dynamic changes of the sarcoplasmic structural components, the myofibrils showed a progressive decrease in diameter after denervation and throughout the period studied. By carrying out tissue fractionation experiments, the yield of microsome-protein was found significantly greater in the denervated muscles, as compared with the contralateral controls, in this initial stage. Under the conditions attending the overdevelopment of the sarcoplasmic reticulum (SR), denervated semitendinosus m. incorporated valine-C(14) into proteins more actively than the control pairs. The denervated muscles also showed an increase in the number of freely scattered and membrane-bound ribosomes and of polyribosomes, suggesting a more active synthesis of the SR membranes. Pronounced atrophy of the myofibrils, disorganization of the SR, and an increased number of ribonucleoprotein particles lying in the enlarged interfibrillar spaces were the main ultrastructural features of "degenerative atrophy" in frog muscle in the late periods after denervation. The probably adaptive character of the early changes occurring on denervation of frog muscle is discussed.

Glycerylphosphorylcholine and choline glycerophosphate

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