Retinal neurodegeneration is an early event in the pathogenesis of diabetic retinopathy (DR). Since glucagon-like peptide 1 (GLP-1) exerts neuroprotective effects in the central nervous system and ...the retina is ontogenically a brain-derived tissue, the aims of the current study were as follows: 1) to examine the expression and content of GLP-1 receptor (GLP-1R) in human and db/db mice retinas; 2) to determine the retinal neuroprotective effects of systemic and topical administration (eye drops) of GLP-1R agonists in db/db mice; and 3) to examine the underlying neuroprotective mechanisms. We have found abundant expression of GLP-1R in the human retina and retinas from db/db mice. Moreover, we have demonstrated that systemic administration of a GLP-1R agonist (liraglutide) prevents retinal neurodegeneration (glial activation, neural apoptosis, and electroretinographical abnormalities). This effect can be attributed to a significant reduction of extracellular glutamate and an increase of prosurvival signaling pathways. We have found a similar neuroprotective effect using topical administration of native GLP-1 and several GLP-1R agonists (liraglutide, lixisenatide, and exenatide). Notably, this neuroprotective action was observed without any reduction in blood glucose levels. These results suggest that GLP-1R activation itself prevents retinal neurodegeneration. Our results should open up a new approach in the treatment of the early stages of DR.
Summary Background Population pharmacokinetic data suggest axitinib plasma exposure correlates with efficacy in metastatic renal-cell carcinoma. Axitinib dose titration might optimise exposure and ...improve outcomes. We prospectively assessed the efficacy and safety of axitinib dose titration in previously untreated patients with metastatic renal-cell carcinoma. Methods In this randomised, double-blind, multicentre, phase 2 study, patients were enrolled from 49 hospitals and outpatient clinics in the Czech Republic, Germany, Japan, Russia, Spain, and USA. Patients with treatment-naive metastatic renal-cell carcinoma received axitinib 5 mg twice daily during a 4 week lead-in period. Those patients with blood pressure 150/90 mm Hg or lower, no grade 3 or 4 treatment-related toxic effects, no dose reductions, and no more than two antihypertensive drugs for 2 consecutive weeks were stratified by Eastern Cooperative Oncology Group performance status (0 vs 1), and then randomly assigned (1:1) to either masked titration with axitinib to total twice daily doses of 7 mg, and then 10 mg, if tolerated, or placebo titration. Patients who did not meet these criteria continued without titration. The primary objective was comparison of the proportion of patients achieving an objective response between randomised groups. Safety analyses were based on all patients who received at least one dose of axitinib. This ongoing trial is registered with ClinicalTrials.gov , number NCT00835978. Findings Between Sept 2, 2009, and Feb 28, 2011, we enrolled 213 patients, of whom 112 were randomly assigned to either the axitinib titration group (56 patients) or the placebo titration group (56 patients). 91 were not eligible for titration, and ten withdrew during the lead-in period. 30 patients (54%, 95% CI 40–67) in the axitinib titration group had an objective response, as did 19 patients (34%, 22–48) in the placebo titration group (one-sided p=0·019). 54 (59%, 95% CI 49–70) of non-randomised patients achieved an objective response. Common grade 3 or worse, all-causality adverse events in treated patients were hypertension (ten 18% of 56 in the axitinib titration group vs five 9% of 56 in the placebo titration group vs 45 49% of 91 in the non-randomised group), diarrhoea (seven 13% vs two 4% vs eight 9%), and decreased weight (four 7% vs three 5% vs six 7%). One or more all-causality serious adverse events were reported in 15 (27%) patients in the axitinib titration group, 13 (23%) patients in the placebo titration group, and 35 (38%) non-randomised patients. The most common serious adverse events in all 213 patients were disease progression and dehydration (eight each 4%), and diarrhoea, vomiting, pneumonia, and decreased appetite (four each 2%). Interpretation The greater proportion of patients in the axitinib titration group achieving an objective response supports the concept of individual axitinib dose titration in selected patients with metastatic renal-cell carcinoma. Axitinib shows clinical activity with a manageable safety profile in treatment-naive patients with this disease. Funding Pfizer Inc.
The incidence, prevalence, and molecular epidemiology of urea cycle disorders (UCDs) in Argentina remain underexplored. The present study is the first to thoroughly assess the clinical and molecular ...profiles of UCD patients examined at a single reference center in Argentina.
Forty-nine UCD cases were collected. About half (26/49, 53%) manifested neonatally with classical presentation and had a high mortality (25/26, 96%). Ornithine transcarbamylase deficiency (OTCD) was the most common UCD (26 patients). Argininosuccinate synthetase deficiency (ASSD) was detected in 19 cases, while argininosuccinate lyase deficiency (ASLD) was diagnosed in 4 cases. Molecular genetic analysis revealed 8 private OTC mutations and two large deletion/duplication events in the OTC gene. Most mutations in the ASS1 and ASL genes were recurrent missense changes, and four alterations were novel. The clinical outcome of our UCD cohort was poor, with an overall mortality of 57% (28/49 cases), and a 28% (6/21) disability rate among the survivors.
Most patients in our case series showed severe neonatal onset, with high morbidity/mortality. We detected in total 19 mutations, most of them recurrent and of high frequency worldwide. Noteworthy, we highlight the presence of a geographic cluster with high prevalence of a point mutation in the ASS1 gene. This study suggests that these disorders may be more frequent than commonly assumed, and stresses the need for increased awareness amongst health professionals and greater availability of diagnostic tools for accurate identification, early diagnosis, and timely treatment.
To assess the long-term efficacy and toxicity of front-line cisplatin-based chemotherapy in patients with stage IIA or IIB testicular seminoma.
Untreated patients with pure seminoma of the testis ...after orchiectomy, with clinical stage IIA or IIB, were considered eligible for this prospective observational study. Chemotherapy consisted of either four cycles of cisplatin and etoposide or three cycles of cisplatin, etoposide, and bleomycin.
Between April 1994 and March 2003, 72 patients were entered onto the study at 26 participating centers. Eighteen patients had stage IIA disease, and 54 patients had stage IIB disease. Eighty-three percent of patients achieved complete response, and 17% achieved partial response with residual mass. After a median follow-up time of 71.5 months, six patients with stage IIB disease experienced relapse, and one of these patients died as a result of seminoma. Three patients experienced non-seminoma-related deaths (two died from a further esophageal carcinoma, and one died from an upper digestive hemorrhage). The estimated 5-year progression-free survival rates for patients with stage IIA or IIB disease were 100% and 87% (95% CI, 77.5% to 97%), respectively. Five-year progression-free and overall survival rates for the whole group were 90% (95% CI, 82% to 98%) and 95% (95% CI, 89% to 100%), respectively. Severe granulocytopenia and thrombocytopenia were observed in eight and two patients, respectively. Mild to moderate emesis, stomatitis, and diarrhea were the most common nonhematologic effects.
Chemotherapy is a highly effective and well-tolerated treatment for patients with stage IIA or IIB seminoma and represents an available alternative that could avoid some of the serious late effects associated with radiotherapy. Further studies focusing on long-term toxicities of different treatment modalities are needed.
Tetraspanins (Tspan) are transmembrane proteins with important scaffold and signalling functions. Deletions of Tetraspanin 6 (Tspan6) gene, a member of the tetraspanin family, have been reported in ...patients with Epilepsy Female-restricted with Mental Retardation (EFMR). Interestingly, mutations in Tspan7, highly homologous to Tspan6, are associated with X-linked intellectual disability, suggesting that these two proteins are important for cognition. Considering recent evidences showing that Tspan7 plays a key role in synapse development and AMPAR trafficking, we initiated the study of Tspan6 in synaptic function using a Tspan6 knock out mouse model. Here we report that hippocampal field recordings from Tspan6 knock out mice show an enhanced basal synaptic transmission and impaired long term potentiation (LTP). A normal paired-pulse facilitation response suggests that Tspan6 affects the properties of the postsynaptic rather than the presynaptic terminal. However, no changes in spine morphology or postsynaptic markers could be detected in Tspan6 KO mice compared with wild types. In addition, Tspan6 KO mice show normal locomotor behaviour and no defects in hippocampus-dependent memory tests.
The primary purpose of this study was to determine if farletuzumab, an antifolate receptor-α monoclonal antibody, improved progression-free survival (PFS) versus placebo when added to standard ...chemotherapy regimens in patients with platinum-sensitive recurrent ovarian cancer (OC) in first relapse (platinum-free interval: 6–36 months) with low cancer antigen 125 (CA-125) levels.
Eligibility included CA-125 ≤ 3 x upper limit of normal (ULN, 105 U/mL), high-grade serous, platinum-sensitive recurrent OC, previous treatment with debulking surgery, and first-line platinum-based chemotherapy with 1st recurrence between 6 and 36 months since frontline platinum-based treatment. Patients received investigator's choice of either carboplatin (CARBO)/paclitaxel (PTX) every 3 weeks or CARBO/pegylated liposomal doxorubicin (PLD) every 4 weeks x6 cycles in combination with either farletuzumab 5 mg/kg weekly or placebo randomized in a 2:1 ratio. Maintenance treatment with farletuzumab (5 mg/kg weekly) or placebo was given until disease progression or intolerance.
214 patients were randomly assigned to farletuzumab+chemotherapy (142 patients) versus placebo+chemotherapy (72 patients). The primary efficacy endpoint, PFS, was not significantly different between treatment groups (1-sided α = 0.10; p-value = 0.25; hazard ratio HR = 0.89, 80% confidence interval CI: 0.71, 1.11), a median of 11.7 months (95% CI: 10.2, 13.6) versus 10.8 months (95% CI: 9.5, 13.2) for farletuzumab+chemotherapy and placebo+chemotherapy, respectively. No new safety concerns were identified with the combination of farletuzumab+chemotherapy.
Adding farletuzumab to standard chemotherapy does not improve PFS in patients with OC who were platinum-sensitive in first relapse with low CA-125 levels. Folate receptor-α expression was not measured in this study.
(Clinical Trial Registry NCT02289950)
•Farletuzumab is an anti-folate receptor-α (FR-α) monoclonal antibody with antitumor activity in ovarian cancer (OC).•Farletuzumab given in first relapse, platinum-sensitive, recurrent OC with low cancer antigen 125 (CA-125) was investigated.•Adding farletuzumab to standard chemotherapy does not improve PFS in these patients.
To assess the efficacy of a risk-adapted treatment policy for patients with stage I seminoma by using universally accepted risk criteria.
Between 1999 and 2003, 314 patients with clinical stage I ...seminoma after orchiectomy were prospectively included. One hundred patients (31.8%) presented no risk factors and were managed with surveillance. In contrast, 131 patients (41.7%) had tumors larger than 4 cm, 33 patients (10.5%) had rete testis involvement, and 50 patients (15.9%) had both risk factors. All the latter received two courses of adjuvant carboplatin.
Chemotherapy was well tolerated, as only 17 patients (7.9%) presented grade 3 to 4 toxicity. Relapses were observed in six patients (6.0%) on surveillance and in seven patients (3.3%) treated with carboplatin (0.8% of tumors larger than 4 cm, 9.1% of those involving the rete testis, and 6.0% of patients with both risk criteria). All were located at the retroperitoneum, except for one at the spermatic cord. Median tumor size was 25 mm (range, 11 to 70 mm), and median time to relapse was 9 months (range, 4 to 28 months). All patients were rendered disease-free with chemotherapy (etoposide plus cisplatin). Median follow-up was 34 months (range, 12 to 72 months). The actuarial 5-year disease-free survival rate was 93.4% for patients on surveillance and 96.2% for patients treated with adjuvant chemotherapy. Overall 5-year survival was 100%.
Adjuvant carboplatin is effective in reducing the relapse rate in patients with stage I seminoma and risk factors. A risk-adapted strategy is safe and feasible and should be considered an alternative to systematic approaches, such as irradiation, chemotherapy, or surveillance.
RuvB-Like transcription factors function in cell cycle regulation, development and human disease, such as cancer and heart hyperplasia. The mechanisms that regulate adenosine triphosphate ...(ATP)-dependent activity, oligomerization and post-translational modifications in this family of enzymes are yet unknown. We present the first crystallographic structure of full-length human RuvBL2 which provides novel insights into its mechanistic action and biology. The ring-shaped hexameric RuvBL2 structure presented here resolves for the first time the mobile domain II of the human protein, which is responsible for protein-protein interactions and ATPase activity regulation. Structural analysis suggests how ATP binding may lead to domain II motion through interactions with conserved N-terminal loop histidine residues. Furthermore, a comparison between hsRuvBL1 and 2 shows differences in surface charge distribution that may account for previously described differences in regulation. Analytical ultracentrifugation and cryo electron microscopy analyses performed on hsRuvBL2 highlight an oligomer plasticity that possibly reflects different physiological conformations of the protein in the cell, as well as that single-stranded DNA (ssDNA) can promote the oligomerization of monomeric hsRuvBL2. Based on these findings, we propose a mechanism for ATP binding and domain II conformational change coupling.
Confirm in patients with cirrhosis and gastrointestinal bleeding the safety of ornithine phenylacetate (OP) and assess the pharmacokinetic profile of OP and its effects on plasma ammonia.
OP is a ...drug that has shown experimentally to decrease hyperammonemia and improve hepatic encephalopathy. OP is safe in healthy subjects and in stable patients with cirrhosis, but there are no data in decompensated cirrhosis.
We performed a study to assess safety and tolerance of OP in cirrhotic patients after an episode of upper gastrointestinal bleeding.Ten patients were included within 24 hours of an upper gastrointestinal bleeding. OP was administered as a continuous infusion up to a maximum of 10 g/24 h (0.42 g/h) for 5 days. The infusion was started at 33% of the target dose and increased at 12-hour intervals achieving target dose at 24 hours. Ammonia was also assessed in control group of 10 patients.
No severe adverse events were observed. Mild adverse events were reported in 4 patients. Plasma ammonia (baseline: 80±43 μmol/L) showed a progressive drop between baseline and 36 hours (42±15 μmol/L), 72 hours (44±15 μmol/L), 96 hours (40±24 μmol/L), and 120 hours (33±14 μmol/L). Plasma ammonia at 24 hours was significantly higher in the control group. Plasma glutamine showed a significant decrease (-37% at day 5) and its excretion in urine as phenylacetylglutamine, a progressive rise (52±35 mmol at day 5).
OP is a safe and well-tolerated drug in decompensated cirrhotics that may decrease plasma ammonia by inducing its appearance as phenylacetylglutamine in urine.
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