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Carboplatin and paclitaxel plus avelumab compared with carboplatin and paclitaxel in advanced or recurrent endometrial cancer (MITO END-3): a multicentre, open-label, randomised, controlled, phase 2 trial. Lancet Oncol 2023; 24:286-296. [PMID: 37052965 DOI: 10.1016/s1470-2045(23)00016-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 02/16/2023]
Abstract
BACKGROUND Adding immunotherapy to first-line chemotherapy might improve outcomes for patients with advanced or recurrent endometrial cancer. We aimed to compare carboplatin and paclitaxel versus avelumab plus carboplatin and paclitaxel as first-line treatment with avelumab given concurrent to chemotherapy and as maintenance after the end of chemotherapy. METHODS MITO END-3 is an open-label, randomised, controlled, phase 2 trial conducted at 31 cancer institutes, hospitals, and universities in Italy. Eligible patients were aged 18 years or older with histologically confirmed advanced (FIGO stage III-IV) or recurrent endometrial cancer, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and no previous systemic anticancer therapy as primary treatment for advanced or metastatic disease. Participants were randomly assigned (1:1) using a computerised minimisation procedure stratified by centre, histology, and stage at study entry, to either receive carboplatin (area under the curve [AUC] 5 mg/mL × min) and paclitaxel (175 mg/m2; standard group) intravenously every 3 weeks for six to eight cycles or avelumab (10 mg/kg intravenously) added to carboplatin and paclitaxel (experimental group) every 3 weeks and then every 2 weeks as a single maintenance treatment after the end of chemotherapy until disease progression or unacceptable toxicity. Patients, treating clinicians, and those assessing radiological examinations were not masked to study treatment. The primary endpoint was investigator-assessed progression-free survival, measured in the intention-to-treat (ITT) population. Patients who received at least one dose of study drug were included in the safety analysis. Experimental group superiority was tested with 80% power and one-tailed α 0·20. This trial is registered with ClinicalTrials.gov (NCT03503786) and EudraCT (2016-004403-31). FINDINGS From April 9, 2018, to May 13, 2021, 166 women were assessed for eligibility and 39 were excluded. 125 eligible patients were randomly assigned to receive carboplatin and paclitaxel (n=62) or avelumab plus carboplatin and paclitaxel (n=63) and included in the ITT population. The median follow-up was 23·3 months (IQR 13·2-29·6) and was similar between the two groups. 91 progression-free survival events were reported, with 49 events in 62 patients in the standard group and 42 events in 63 patients in the experimental group. The median progression-free survival was 9·9 months (95% CI 6·7-12·1) in the standard group and 9·6 months (7·2-17·7) in the experimental group (HR of progression or death 0·78 [60% CI 0·65-0·93]; one-tailed p=0·085). Serious adverse events were reported more frequently in the experimental group (24 vs seven events in the standard group); neutrophil count decrease was the most frequent grade 3-4 adverse event (19 [31%] of 61 patients in the experimental group vs 26 [43%] of 61 patients in the standard group). Two deaths occurred in the experimental group during treatment (one respiratory failure following severe myositis [possibly related to treatment] and one cardiac arrest [not related to treatment]). INTERPRETATION Adding avelumab to first-line chemotherapy deserves further testing in patients with advanced or recurrent endometrial cancer, although consideration of mismatch repair status is warranted. FUNDING Pfizer.
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Pathologic Findings at Risk Reducing Surgery in BRCA and Non- BRCA Mutation Carriers: A Single-Center Experience. Diagnostics (Basel) 2022; 12:diagnostics12123054. [PMID: 36553061 PMCID: PMC9776991 DOI: 10.3390/diagnostics12123054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Risk-reducing surgery (RRS) is recommended in BRCA-mutated carriers because of their increased risk of developing ovarian cancer, while its role is still discussed for women harboring mutations in non-BRCA homologous repair genes. The aim of this study was to retrospectively evaluate the occurrence of pathological findings in a high-risk population undergoing RRS in San Matteo Hospital, Pavia between 2012 and 2022, and correlate their genetic and clinical outcomes, comparing them with a control group. The final cohort of 190 patients included 85 BRCA1, 63 BRCA2, 11 CHEK2, 7 PALB2, 4 ATM, 1 ERCC5, 1 RAD51C, 1 CDH1, 1 MEN1, 1 MLH1 gene mutation carriers and 15 patients with no known mutation but with strong familial risk. Occult invasive serous carcinoma (HGSC) and serous tubal intraepithelial carcinoma (STIC) were diagnosed in 12 (6.3%) women, all of them BRCA carriers. No neoplastic lesion was diagnosed in the non-BRCA group, in women with familial risk, or in the control group. Oral contraceptive use and age ≤45 at surgery were both found to be favorable factors. While p53 signature and serous tubal intraepithelial lesion (STIL) were also seen in the control group and in non-BRCA carriers, STIC and HGSC were only found in BRCA1/2 mutation carriers.
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590P Ki67 as a predictor of response to PARP inhibitors in platinum sensitive BRCA wild type ovarian cancers: MITO 37 retrospective study. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Human Umbilical Cord Mesenchymal Stem Cell-Based in vitro Model for Neurotoxicity Testing. Curr Protoc 2022; 2:e423. [PMID: 35471597 DOI: 10.1002/cpz1.423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Neurotoxicity (NT) testing for regulatory purposes is based on in vivo animal testing. There is general consensus, however, about the need for the development of alternative methodologies to allow researchers to more rapidly and cost effectively screen large numbers of chemicals for their potential to cause NT, or to investigate their mode of action. In vitro assays are considered an important source of information for making regulatory decisions, and human cell-based systems are recommended as one of the most relevant models in toxicity testing, to reduce uncertainty in the extrapolation of results from animal-based models. Human neuronal models range from various neuroblastoma cell lines to stem cell-derived systems, including those derived from mesenchymal stem/stromal cells (hMSC). hMSCs exhibit numerous advantages, including the fact that they can be obtained in high yield from healthy human adult tissues, can be cultured with a minimal laboratory setup and without genetic manipulations, are able of continuous and repeated self-renewal, are nontumorigenic, and can form large populations of stably differentiated cells representative of different tissues, including neuronal cells. hMSCs derived from human umbilical cord (hUC) in particular possess several prominent advantages, including a painless, non-invasive, and ethically acceptable collection procedure, simple and convenient preparation, and high proliferation capacity. In addition, hMSCs can be efficiently differentiated into neuron-like cells (hNLCs), which can then be used for the assessment of neuronal toxicity of potential neurotoxic compounds in humans. Here, we describe a step-by-step procedure to use hMSCs from the umbilical cord for in vitro neurotoxicity testing. First, we describe how to isolate, amplify, and store hMSCs derived from the umbilical cord. We then outline the steps to transdifferentiate these cells into hNLCs, and then use the hNLCs for neurotoxicity testing by employing multiple common cytotoxicity assays after treatment with test compounds. The approach follows the most updated guidance on using human cell-based systems. These protocols will allow investigators to implement an alternative system for obtaining primary NLCs of human origin, and support advancement in neurotoxicity research. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Isolation and maintenance of human mesenchymal stem/stromal cells (hMSCs) obtained from the umbilical cord lining membrane Basic Protocol 2: Transdifferentiation of hMSCs into neuron-like cells (hNLCs) and basic neurotoxicity assessment.
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Hadrontherapy for intra- or para-cardiac tumors: evaluation of cardiac radiation dose distribution and acute cardiac effects. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
There is growing interest in the possibility of using X-rays and hadrons (protons and carbon ions) for antiarrhythmic purposes both at the ventricular and the atrial level, but knowledge about the effects on cardiac tissue outside the target is still limited. Hadron therapy has the dosimetric advantage over photons of a greater ability to concentrate high doses on the target while minimizing the off-target dose. Oncological studies have shown a linear relationship between the mean total heart dose (Dm-heart) of X-rays and the long-term risk of heart damage, particularly when the Dm-heart is>5 Gray (Gy).
Objectives
We designed a prospective study aimed at investigating the effect of heavy particles on cardiac structure and function and on cardiac rhythm in patients undergoing hadrontherapy for intra or para-cardiac tumors.
Methods
Patients candidates to hadrontherapy with a mean predicted cardiac dose grather than zero underwent close cardiological monitoring including blood pressure detection, 12-lead ECG, 12-lead Holter ECG (including time-domain indices of heart rate variability in all cases and Brugada leads in selected cases), cardiac US and cardiac (troponin and natriuretic peptides) and inflammatory biomarkers. These assessments were obtained at baseline, during (ECG and biomarkers only) and at the end of the hadrontherapy cycle, and then every 3–6 months as appropriate. Physicists and radiotherapists collaborated to implement a robust optimization of the treatment plan aimed at minimizing cardiac dose. We present the results of the monitoring up to the end of the hadrontherapy.
Results
17 consecutive patients (56±18 years, range 20–77 years, 59% male) have been enrolled to date, including 3 cases (18%) of intra-cardiac tumors (2 primary and 1 metastatic), who have undergone to 16±6 sessions of radiotherapy each, in 71% of cases with respiratory gating during delivery. Most patients (76%) were treated with carbon ions, the remaining with protons (mean total dose on the neoplastic target 51.8±10.7 Gy, from 2 to 4.2 Gy per fraction). Sixty-one percent of patients had ≥1 cardiovascular risk factor, 6% had a known heart disease (valvular cardiomyopathy despite aortic valve replacement with biological prosthesis and post-surgical pericarditis). The mean dose on the whole heart was 3.58±2.05 Gy, the maximum dose was 33.78±23.99 Gy, with a very variable dose distribution on cardiac substructures depending on the tumor site (table). At the end of the scheduled radiotherapy sessions (24±9 days), no significant changes were observed in cardiac function, cardiac rhythm, ventricular repolarization, biomarkers and autonomic indices.
Conclusions
Hadrontherapy with protons and carbon ions aimed at the treatment of para-cardiac or intra-cardiac tumors allowed to maintain a low heart Dm and showed no signs of acute cardiac toxicity. The collection of potential cardiac effects in the medium and long term is ongoing.
Funding Acknowledgement
Type of funding sources: None.
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Is a tailored strategy using proton beam radiotherapy for reirradiation advantageous for elderly women? A case report. TUMORI JOURNAL 2021; 107:NP67-NP72. [PMID: 33896256 DOI: 10.1177/03008916211007930] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The management of primary or recurrent vaginal tumours in an aging population is challenging for gynecologic and radiation oncologists. In patients unsuited for surgery and already irradiated on the pelvis, proton beam radiotherapy may be worthwhile due to its ballistic advantages. CASE REPORT We report the case of an 80-year-old woman with a squamous cell carcinoma of the vagina after a history of pelvic radiation and vaginal brachytherapy delivered for a previous endometrial adenocarcinoma. She received proton beam radiotherapy with a complete response after 12 months and mild toxicity. CONCLUSIONS The complexity of reirradiation management in the frail and elderly population requires attention. Efforts should be focused on maintaining autonomy and quality of life in order to improve adherence and clinical compliance to the treatment. In the era of the tailored approach, hadrontherapy can play an important role to minimize toxicity, obtain good local control, and reduce the overall treatment time.
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Endometrial Cancer: When Upfront Surgery Is Not an Option. Oncology 2020; 99:65-71. [PMID: 33032278 DOI: 10.1159/000510690] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 08/04/2020] [Indexed: 11/19/2022]
Abstract
Background and Summary: The management of endometrial cancer, in an ever-older population with considerable comorbidity, remains a challenge for gynecological and radiation oncologists. Key Message: The present paper reviews literature data on treatment options for endometrial cancer patients unfit for surgery.
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In vitro toxicity screening of magnetite nanoparticles by applying mesenchymal stem cells derived from human umbilical cord lining. J Appl Toxicol 2019; 39:1320-1336. [PMID: 31211441 DOI: 10.1002/jat.3819] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/18/2019] [Accepted: 04/18/2019] [Indexed: 01/05/2023]
Abstract
Despite the growing interest in nanoparticles (NPs), their toxicity has not yet been defined and the development of new strategies and predictive models are required. Human stem cells (SCs) offer a promising and innovative cell-based model. Among SCs, mesenchymal SCs (MSCs) derived from cord lining membrane (CL) may represent a new species-specific tool for establishing efficient platforms for primary screening and toxicity/safety testing of NPs. Superparamagnetic iron oxide NPs, including magnetite (Fe3 O4 NPs), have aroused great public health and scientific concerns despite their extensive uses. In this study, CL-MSCs were characterized and applied for in vitro toxicity screening of Fe3 O4 NPs. Cytotoxicity, internalization/uptake, differentiation and proliferative capacity were evaluated after exposure to different Fe3 O4 NP concentrations. Data were compared with those obtained from bone marrow (BM)-MSCs. We observed, at early passages (P3), that: (1) cytotoxicity occurred at 10 μg/mL in CL-MSCs and 100 μg/mL in BM-MSCs (no differences in toxicity, between CL- and BM-MSCs, were observed at higher dosage, 100-300 μg/mL); (2) cell density decrease and monolayer features loss were affected at ≥50 μg/mL in CL-MSCs only; and (3) NP uptake was concentration-dependent in both MSCs. After 100 μg/mL Fe3 O4 NP exposures, the capacity of proliferation was decreased (P5-P9) in CL-MSCs without morphology alteration. Moreover, a progressive decrease of intracellular Fe3 O4 NPs was observed over culture time. Antigen surface expression and multilineage differentiation were not influenced. These findings suggest that CL-MSCs could be used as a reliable cell-based model for Fe3 O4 NP toxicity screening evaluation and support the use of this approach for improving the confidence degree on the safety of NPs to predict health outcomes.
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3D spheroid cultures from human astrocyte- and neuronal- like cells: New in vitro models to assess magnetite nanoparticle-induced adverse effects on CNS. Toxicol Lett 2018. [DOI: 10.1016/j.toxlet.2018.06.656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Human 3D Cultures as Models for Evaluating Magnetic Nanoparticle CNS Cytotoxicity after Short- and Repeated Long-Term Exposure. Int J Mol Sci 2018; 19:ijms19071993. [PMID: 29986546 PMCID: PMC6073335 DOI: 10.3390/ijms19071993] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/02/2018] [Accepted: 07/04/2018] [Indexed: 11/20/2022] Open
Abstract
Since nanoparticles (NPs) can translocate to the brain and impact the highly vulnerable central nervous system (CNS), novel in vitro tools for the assessment of NP-induced neurotoxicity are advocated. In this study, two types of CNS spheroids have been developed from human D384 astrocyte- and SH-SY5Y neuronal-like cells, and optimized in combination with standard assays (viability readout and cell morphology) to test neurotoxic effects caused by Fe3O4NPs, as NP-model, after short- (24–48 h; 1–100µg/ml) and long-term repeated exposure (30days; 0.1–25µg/ml). Short-term exposure of 3D-spheroids to Fe3O4NP induced cytotoxicity at 10 µg/mL in astrocytes and 25 µg/mL neurons. After long-term repeated dose regimen, spheroids showed concentration- and time-dependent cell mortality at 10 µg/mL for D384 and 0.5 µg/mL for SH-SY5Y, indicating a higher susceptibility of neurons than astrocytes. Both spheroid types displayed cell disaggregation after the first week of treatment at ≥0.1 µg/mL and becoming considerably evident at higher concentrations and over time. Recreating the 3D-spatial environment of the CNS allows cells to behave in vitro more closely to the in vivo situations, therefore providing a model that can be used as a stand-alone test or as a part of integrated testing strategies. These models could drive an improvement in the species-relevant predictivity of toxicity testing.
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Conductive hybrid carbon nanotube (CNT)–polythiophene coatings for innovative auditory neuron-multi-electrode array interfacing. RSC Adv 2016. [DOI: 10.1039/c5ra27642j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Surface modification of platinum electrodes to improve neuron-electrode interface and electrode conductive properties in cochlear implants.
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Cell cycle reactivation of cochlear progenitor cells in neonatal FUCCI mice by a GSK3 small molecule inhibitor. Sci Rep 2015; 5:17886. [PMID: 26643939 PMCID: PMC4672274 DOI: 10.1038/srep17886] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 11/06/2015] [Indexed: 11/09/2022] Open
Abstract
Due to the lack of regenerative capacity of the mammalian auditory epithelium, sensory hair cell loss results in permanent hearing deficit. Nevertheless, a population of tissue resident stem/progenitor cells has been recently described. Identification of methods to trigger their activity could lead to exploitation of their potential therapeutically. Here we validate the use of transgenic mice reporting cell cycle progression (FUCCI), and stemness (Lgr5-GFP), as a valuable tool to identify regulators of cell cycle re-entry of supporting cells within the auditory epithelium. The small molecule compound CHIR99021 was used to inhibit GSK3 activity. This led to a significant increase in the fraction of proliferating sphere-forming cells, labeled by the FUCCI markers and in the percentage of Lgr5-GFP + cells, as well as a selective increase in the fraction of S-G2-M cells in the Lgr5 + population. Using whole mount cultures of the organ of Corti we detected a statistically significant increment in the fraction of proliferating Sox2 supporting cells after CHIR99021 treatment, but only rarely appearance of novel MyoVIIa+/Edu + hair cells. In conclusion, these tools provide a robust mean to identify novel regulators of auditory organ regeneration and to clarify the contribution of stem cell activity.
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Conditioned medium from human amniotic mesenchymal stromal cells limits infarct size and enhances angiogenesis. Stem Cells Transl Med 2015; 4:448-58. [PMID: 25824141 DOI: 10.5966/sctm.2014-0253] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/02/2015] [Indexed: 01/08/2023] Open
Abstract
The paracrine properties of human amniotic membrane-derived mesenchymal stromal cells (hAMCs) have not been fully elucidated. The goal of the present study was to elucidate whether hAMCs can exert beneficial paracrine effects on infarcted rat hearts, in particular through cardioprotection and angiogenesis. Moreover, we aimed to identify the putative active paracrine mediators. hAMCs were isolated, expanded, and characterized. In vitro, conditioned medium from hAMC (hAMC-CM) exhibited cytoprotective and proangiogenic properties. In vivo, injection of hAMC-CM into infarcted rat hearts limited the infarct size, reduced cardiomyocyte apoptosis and ventricular remodeling, and strongly promoted capillary formation at the infarct border zone. Gene array analysis led to the identification of 32 genes encoding for the secreted factors overexpressed by hAMCs. Among these, midkine and secreted protein acidic and rich in cysteine were also upregulated at the protein level. Furthermore, high amounts of several proangiogenic factors were detected in hAMC-CM by cytokine array. Our results strongly support the concept that the administration of hAMC-CM favors the repair process after acute myocardial infarction.
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Multiple human papillomavirus infection with or without type 16 and risk of cervical intraepithelial neoplasia among women with cervical cytological abnormalities. Cancer Causes Control 2014; 25:1669-76. [PMID: 25296710 DOI: 10.1007/s10552-014-0471-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 09/30/2014] [Indexed: 12/27/2022]
Abstract
PURPOSE To evaluate the impact of multiple human papillomavirus (HPV) infections on the risk of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) in subjects with cervical cytological abnormalities. METHODS A cross-sectional study of 3,842 women attending a colposcopy service was carried out. Genotyping of 18 high-risk, seven low-risk, and two undefined-risk HPVs was carried out by the INNO-LiPA genotyping system. RESULTS The final colposcopic/pathological diagnoses were as follows: 1,933 (50.3 %) subjects were negative; 1,041 (27.1 %) CIN1; 280 (7.3 %) CIN2; 520 (13.5 %) CIN3; and 68 (1.8 %) invasive cervical cancer. The prevalence of HPV infection was 75.8 % (2,911/3,842), whereas multiple HPVs were detected in 34.5 % of HPV-positive subjects (2,255/3,842). The adjusted risks of CIN3+ in the group with multiple compared to the group with single infection were 2.31 (95 % CI = 1.54-3.47), among HPV16-positive women, and 3.25 (95 % CI = 2.29-4.61, p = 0.21 compared with HPV16-positive subjects), in HPV16-negative subjects. Out of a total of 1,285 subjects with mild lesions, followed up for a median of 16.1 months (interquartile range = 8.9-36.8), the rate of progression to CIN2-3 was 0.6 % (5/541) among subjects negative or with low-risk HPVs, 1.7 % (8/463) among those with single high-risk HPV, and 5 % (14/281, p < 0.001 compared with HPV-negative/low-risk HPV and p = 0.038 compared with single high-risk HPV) among those with multiple high-risk HPVs. CONCLUSIONS Among women with cervical cytological abnormalities, infection by multiple high-risk HPVs increased the risk of CIN3+ in both HPV16-positive and HPV16-negative subjects. These findings suggest a potential synergistic interaction between high-risk HPVs, favoring the progression of CIN lesions.
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Untypable human papillomavirus infection and risk of cervical intraepithelial neoplasia among women with abnormal cervical cytology. J Med Virol 2014; 86:1145-52. [DOI: 10.1002/jmv.23938] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2014] [Indexed: 11/06/2022]
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The W520X mutation in the TSHR gene brings on subclinical hypothyroidism through an haploinsufficiency mechanism. J Endocrinol Invest 2013; 36:716-21. [PMID: 23563316 DOI: 10.3275/8930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND TSHR is a G-protein-coupled seven transmembrane domain receptor that activates the two major signal transduction pathways: the Gαs/adenylate cyclase and the Gαq/11/phospholipase C pathways. Inactivating mutations in the TSHR gene have been demonstrated to be responsible for subclinical hypothyroidism, a disorder characterized by elevated serum TSH concentrations despite normal thyroid hormones levels. AIM We identified in a child a nonsense mutation (W520X) in the third transmembrane domain of the TSHR that causes the lack of the C-terminus portion of the receptor. The functional significance of this variation was assessed in vitro. MATERIAL/SUBJECT AND METHODS The W520X mutation was introduced into the pSVL vector containing the wild-type sequence of TSHR gene. Wild-type and mutated vectors were expressed in Chinese Hamster Ovary (CHO) cells, and cAMP, inositol phosphate (IP), immunofluorescence and FACS analyses were performed. RESULTS Transfection with pSVL-TSHR vector induced basal cAMP and IP production in the absence of TSH stimulation, indicating a constitutive activity for the TSHR. An impairment of receptor function was demonstrated by the observation that cells expressing the mutant TSHR exhibited a lower second messenger production with respect to the wild-type, despite a normal expression of the receptor at the cell surface. CONCLUSIONS The mechanism through which the W520X mutation exerts its effect is more likely haploinsufficiency rather than a dominant-negative effect. This could explain the phenotype of our patient, who has a hormonal pattern in the range of a mild subclinical hypothyroidism, without an overt disease phenotype.
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Pentraxin-3 and galectin-1 are key mediators of the cardioprotective paracrine effects exerted by fetal mesenchymal stem cells isolated from human placenta. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p3271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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HPV infection and intraepithelial lesions: comparison between HIV positive and negative women. Curr HIV Res 2012; 10:614-9. [PMID: 22934657 DOI: 10.2174/157016212803305998] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 06/24/2012] [Accepted: 08/08/2012] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Human Papillomavirus infections have been shown to be crucial for the development of cervical intraepithelial neoplasia and subsequent cervical cancer. The aim of this study is to describe the prevalence of different genotypes of HPV, in a population of HIV-positive women, compared to the negative ones, and their oncogenic risk. PATIENTS AND METHOD A case-control study comparing HPV genotype distribution between 93 HIV-seropositive and 186 HIV-seronegative women, matched for age and severity of cervical lesions, who attending colposcopic service of our departments for periodical Pap smear and HPV DNA full genotyping by SPF-10 LiPA assay. RESULTS No significant difference was found in genotype distribution between HIV positive and HIV negative women. Only the prevalence of HPV56 was higher in HIV positive women (p=0,046). The rates of HPV 6, 11, 16 and 18 were similar in both groups. The likelihood of the detection of three or more HPV genotypes was significantly associated with CIN (OR=2.0; 95% CI=1.1-3.8; p= 0.026) but only marginally to HIV-positive serostatus (OR=1.68; 95% CI=0.89-3.16; p= 0.1). High grade cervical lesions are associated with high risk viruses like HPV 16 and 18 and with multiple cervical HPV infections. CONCLUSIONS The tendency to treat HIV disease with high active antiretroviral therapy may reduce the impact of immunosuppression and make the course of such HPV infections more similar to that among women who are not HIVinfected. As in immunocompetent women, high oncogenic risk viral type and multiple infections are associated with a histologically proven cervical intraepithelial lesions.
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HIV shedding in cervico-vaginal secretions in pregnant women. Curr HIV Res 2012; 9:313-20. [PMID: 21916839 DOI: 10.2174/157016211797636017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2011] [Revised: 08/25/2011] [Accepted: 08/29/2011] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the presence of HIV-1 in cervico-vaginal secretions of pregnant as compared to non-pregnant HIV-seropositive women. PATIENTS AND METHODS We compared 43 known HIV seropositive pregnant patients versus 241 age-matched (± 2 years) control non-pregnant HIV-seropositive subjects. In pregnant patients blood and cervico-vaginal samples were obtained during each trimester of pregnancy. In control subjects the same samples were obtained at enrolment. HIV-1 RNA was measured in plasma; proviral HIV-1 DNA, cell-associated and cell-free HIV-1 RNA in cervico-vaginal secretion by competitive polymerase chain reaction (cRT-PCR) and reverse transcriptase PCR. RESULTS The genital shedding of HIV-DNA (22/43 as compared to 79/241, p = 0.02), and cell-free HIV-RNA detection (26/43 as compared to 72/241, p < .001) was more common in first-trimester pregnant than in non pregnant women. Pregnancy correlated with a significant positive trend in the cervico-vaginal load of HIV-DNA (Spearman Rho= 0.149, p= 0.012), and cell-free HIV-RNA (Spearman Rho= 0.253, p < .001), but not of HIV-RNA transcripts (Spearman Rho = 0.06, p= 0.31). After correction for potential confounders, first trimester pregnant women had increased rates of genital HIV- DNA (odds ratio = 1.94, 95% confidence interval = 1.01 3.78) and cell-free HIV-RNA (odds ratio = 4.07, 95% confidence interval = 1.97 8.41) detection compared to nonpregnant controls. CONCLUSION The shedding of genital HIV was increased in pregnant compared to non pregnant subjects, even in patients with undetectable viremia. In this low-risk HIV-positive population the risks of vertical or horizontal transmissions should not be underestimated.
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Decreased mitochondrial DNA content in subcutaneous fat from HIV-infected women taking antiretroviral therapy as measured at delivery. Antivir Ther 2011; 16:365-72. [PMID: 21555819 DOI: 10.3851/imp1764] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Increasing numbers of pregnant HIV-positive women are receiving combination antiretroviral regimens for preventing mother-to-child virus transmission or for treating the infection itself. Several studies have demonstrated that nucleoside reverse transcriptase inhibitors (NRTIs) induce mitochondrial toxicity by several mechanisms, including depletion of mitochondrial DNA (mtDNA). By the quantification of mtDNA levels, we studied mitochondrial toxicity in HIV-positive women at delivery and the possible correlations with antiretroviral regimens, viroimmunological and metabolic parameters. METHODS We analysed 68 HIV-positive women enrolled in the Italian Prospective Cohort Study on Efficacy and Toxicity of Antiretroviral in Pregnancy (TARGET Study); all were taking ≥1 NRTI. We quantified mtDNA copies per cell in subcutaneous fat samples collected during delivery. At the 3rd, 6th and 9th month of pregnancy, we collected data concerning CD4(+) T-cell count, plasma HIV RNA, total and high-density lipoprotein (HDL) cholesterol, fasting plasma glucose and triglycerides. As a control, we analysed mtDNA levels in abdominal subcutaneous fat samples from 23 HIV-seronegative women at delivery. RESULTS mtDNA content was significantly lower in HIV-infected women when compared with HIV-negative controls. mtDNA content varied independently from viroimmunological, lipid and glucose parameters at the different months, with the exceptions of triglycerides at the 9th month and of HDL at the 6th month of pregnancy. CONCLUSIONS In subcutaneous tissue from women taking NRTI-based antiretroviral regimens, we observed a significant decrease of mtDNA content, compared with uninfected women not on antiviral treatment. Moreover, a significant correlation was noted between mtDNA content and HDL cholesterol and triglycerides.
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Low-dose combined oral contraceptive and cervicovaginal shedding of human immunodeficiency virus. Contraception 2010; 83:564-70. [PMID: 21570555 DOI: 10.1016/j.contraception.2010.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 10/17/2010] [Accepted: 10/18/2010] [Indexed: 11/27/2022]
Abstract
BACKGROUND The role of low-dose oral contraceptives on HIV cervicovaginal shedding among HIV-positive women is controversial. STUDY DESIGN We evaluated the effect of low-dose oral contraceptives on HIV cervicovaginal shedding in a cohort of 285 HIV-seropositive women followed for a median of 20 months. A sensitive, competitive polymerase chain reaction (cPCR) and a reverse transcription PCR (cRT-PCR) were applied for the quantification of HIV-associated and cell-free RNA and proviral DNA in cervicovaginal cells, as well as HIV-RNA in plasma. RESULTS In multivariable logistic generalized estimating equations, plasma viral load >100 copies/mL (OR=1.81, 95% CI=1.3-2.53) and bacterial vaginosis (OR=1.49, 95% CI=1.1-2.02) were associated with an increased risk of HIV-1 DNA shedding, whereas current use of oral contraceptive was associated with a reduced risk (OR=0.55, 95% CI=0.33-0.92). Oral contraceptives were also associated with a reduction of risk (OR=0.38, 95% CI=0.21-0.69) of cell-associated but not cell-free HIV-1 RNA. CONCLUSIONS In HIV-positive women with low levels of HIV viremia, low-dose oral contraceptives were associated with a modest but significant reduction of HIV-1 DNA and cell-associated HIV-1 RNA genital shedding.
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Abstract
AIM To evaluate the effect of the interaction between fetal sex and obstetric variables on the risk of neurodevelopmental impairment among preterm infants. METHOD A cohort study of 394 male and 360 female surviving infants born at 24 to 33 completed weeks of gestational age. Neurological examination and cognitive assessment of the infants (Bayley Scales of Infant Development) were performed at 2 years corrected age. RESULTS Mean gestational age was 30.4 weeks (SD 2.4). Rates of mild and moderate-to-severe neurodevelopmental impairment were 14.6% (110/754) and 7% (53/754) respectively. In logistic analysis, male sex was associated with an increased risk of neurodevelopmental impairment (odds ratio 1.8, 95% confidence interval 1.21-2.68) compared with females. The excess risk of neurodevelopmental impairment associated with male sex was higher among preeclamptic than normotensive pregnancies (p for interaction=0.004), among infants who were either small for gestational age or delivered to a mother with preeclampsia (p for interaction=0.001) and in iatrogenic as opposed to spontaneous preterm birth or preterm premature rupture of membranes (p for interaction=0.035). INTERPRETATION The excess risk of neurodevelopmental impairment associated with male sex among preterm infants is modulated by obstetric risk factors.
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Clustering patterns of human papillomavirus genotypes in multiple infections. Virus Res 2009; 142:154-9. [DOI: 10.1016/j.virusres.2009.02.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 02/05/2009] [Accepted: 02/06/2009] [Indexed: 11/16/2022]
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Cervical infections by multiple human papillomavirus (HPV) genotypes: Prevalence and impact on the risk of precancerous epithelial lesions. J Med Virol 2009; 81:703-12. [PMID: 19235847 DOI: 10.1002/jmv.21429] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A large proportion of human papillomavirus (HPV) infections is sustained by multiple genotypes. The effect of multiple infections on the risk of cervical intraepithelial neoplasia (CIN) and the potential efficacy of vaccine on these infections are controversial. We performed viral typing by SFP(10)-LIPA on a consecutive series of 1,323 women undergoing colposcopy, 69% of whom had cervical biopsy, and correlated CIN severity with the type and number of HPVs. Overall prevalence of HPV-DNA was 68.9%, 97.3% in CIN1, and 98.1% in CIN>/=2. HPV positivity correlated with younger age (35.9 vs. 37.3 years, P = 0.026) and history of CIN (P < 0.001). Multiple types were detected in 44.2% of cases, including 63.1% CIN1 and 80.8% CIN>/=2. Twenty-three different types were detected, HPV-16, 31 and 52 being the most frequent. Infections by HPV-6, 11, 16, or 18 occurred in 59.4% of CIN1 and 71.3% of CIN>/=2. Number of viral types and class of oncogenic risk were linearly correlated with CIN severity (P < 0.0001) by univariate and multivariate analyses controlling for age and history of CIN. The effect of the number of HPV types was maintained after exclusion from the model of infections by HPV-6, 11, 16, and 18. Frequency, distribution, and clinical correlates of multiple HPV infections highlight the importance of assessing individual types in the management and the prediction of outcome of women with abnormal baseline cytology and point to potential limitations in current vaccine strategies.
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Prognostic significance of the interaction between abnormal umbilical and middle cerebral artery Doppler velocimetry in pregnancies complicated by fetal growth restriction. Acta Obstet Gynecol Scand 2009; 88:159-66. [PMID: 19169929 DOI: 10.1080/00016340802632358] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To evaluate the prognostic significance of the interaction between umbilical artery (UA) and middle cerebral artery (MCA) Doppler measurements in pregnancies complicated by fetal growth restriction (FGR). DESIGN Cohort study. SETTING Third-level Perinatology Center in Northern Italy. POPULATION A study of 184 singleton pregnancies at 24-35 weeks' gestational age complicated by FGR and abnormal UA Doppler measurements. METHODS FGR was diagnosed by serial ultrasonograms. Neonatal brain damage was defined as the presence of cystic leukomalacia or grade III-IV intraventricular hemorrhage. MAIN OUTCOME MEASURES Perinatal death and neonatal brain damage. RESULTS The prevalence of fetal/neonatal death or brain damage was 18.2% (16/88) in pregnancies with UA absent/reversed diastolic flow and 4.2% (4/96) in those with increased UA Doppler pulsatility. Stepwise logistic regression identified decreasing gestational age (OR=1.75, 95% confidence interval, CI=1.35-2.22) and absent/reversed UA blood flow (OR=3.34, 95% CI=1.1-10.9) as predictors of fetal/neonatal death or brain damage. A MCA pulsatility index below the 10th percentile was a risk factor for fetal/neonatal death or brain damage among women with absent/reversed UA diastolic flow (14/53 as compared to 2/35; OR=5.9, CI =1.4-40.3) but not in pregnancies with forward velocity (1/33 as compared to 3/63; OR=0.63, 95% CI=0.02-6.13, Synergy index=27.7, p=0.007). CONCLUSIONS In pregnancies complicated by FGR and absent/reversed UA end diastolic flow, vasodilatation of the MCA is a risk factor for neonatal death or brain damage.
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Multiple human papillomavirus infection and high grade cervical intraepithelial neoplasia among women with cytological diagnosis of atypical squamous cells of undetermined significance or low grade squamous intraepithelial lesions. Gynecol Oncol 2009; 113:115-9. [PMID: 19181368 DOI: 10.1016/j.ygyno.2008.12.037] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 12/26/2008] [Accepted: 12/30/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To evaluate the effect of multiple human papillomavirus (HPV) infection on the prevalence of cervical intraepithelial neoplasia (CIN) among women undergoing colposcopy following a cytological diagnosis of atypical squamous cells of undetermined significance (ASCUS) or low grade squamous intraepithelial lesions (LSIL). METHODS HPV type-specific sequences of 15 high-risk and 10 low risk types were detected by the line probe, INNO-LiPA HPV genotyping assay before colposcopic examination and targeted biopsies. Multinomial logistic regression was used to evaluate the effect of multiple infection on pathologic outcome adjusting for confounders. RESULTS The prevalence of HPV infection in the 1218 women enrolled was 69.9% (851/1218). HPV 16 (37.4%), 31 (26.1%), 51 (17.4%), 52 (15.7%) and 18 (14%) were the commonest viral types identified. Overall, the rates of multiple infection were 22.5% (153/680) among subjects with negative colposcopy/biopsy, 63.6% (218/343) and 79.5% (155/195) among those with CIN 1 and CIN>or=2, respectively (p for trend <.001). The corresponding rates among subjects uninfected by HPV 16 or 18 were 13.5% (77/572), 57.4% (112/195) and 62% (48/77), respectively (p for trend <.001). In multinomial logistic regression, the odds ratio of CIN>or=2 in multiple high risk as compared to single high risk HPV infection was 4.33 (95% confidence intervals=2.32-7.14) in the overall population and 2.76 (95% confidence intervals=1.36-5.59) among women uninfected by HPV 16 or 18. CONCLUSIONS Multiple HPV infection is a significant risk factor for CIN>or=2 among women undergoing colposcopy because of ASCUS/LSIL.
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Progenitor cells isolated from the human heart: a potential cell source for regenerative therapy. Neth Heart J 2008; 16:163-9. [PMID: 18566670 PMCID: PMC2431168 DOI: 10.1007/bf03086138] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND In recent years, resident cardiac progenitor cells have been identified in, and isolated from the rodent heart. These cells show the potential to form cardiomyocytes, smooth muscle cells, and endothelial cells in vitro and in vivo and could potentially be used as a source for cardiac repair. However, previously described cardiac progenitor cell populations show immature development and need co-culture with neonatal rat cardiomyocytes in order to differentiate in vitro. Here we describe the localisation, isolation, characterisation, and differentiation of cardiomyocyte progenitor cells (CMPCs) isolated from the human heart. METHODS hCMPCs were identified in human hearts based on Sca-1 expression. These cells were isolated, and FACS, RT-PCR and immunocytochemistry were used to determine their baseline characteristics. Cardiomyogenic differentiation was induced by stimulation with 5-azacytidine. RESULTS hCMPCs were localised within the atria, atrioventricular region, and epicardial layer of the foetal and adult human heart. In vitro, hCMPCs could be induced to differentiate into cardiomyocytes and formed spontaneously beating aggregates, without the need for co-culture with neonatal cardiomyocytes. CONCLUSION The human heart harbours a pool of resident cardiomyocyte progenitor cells, which can be expanded and differentiated in vitro. These cells may provide a suitable source for cardiac regeneration cell therapy. (Neth Heart J 2008;16:163-9.).
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Stem cell sources for cardiac regeneration. Panminerva Med 2008; 50:19-30. [PMID: 18427385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new cardiomyocytes to ameliorate the injured myocardium, compensate for the loss of ventricular mass and contractility and eventually restore cardiac function. An array of cell types has been explored in this respect, including skeletal muscle, bone marrow derived stem cells, embryonic stem cells (ESC) and more recently cardiac progenitor cells. The best-studied cell types are mouse and human ESC cells, which have undisputedly been demonstrated to differentiate into cardiomyocyte and vascular lineages and have been of great help to understand the differentiation process of pluripotent cells. However, due to their immunogenicity, risk of tumor development and the ethical challenge arising from their embryonic origin, they do not provide a suitable cell source for a regenerative therapy approach. A better option, overcoming ethical and allogenicity problems, seems to be provided by bone marrow derived cells and by the recently identified cardiac precursors. This report will overview current knowledge on these different cell types and their application in cardiac regeneration and address issues like implementation of delivery methods, including tissue engineering approaches that need to be developed alongside.
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[Perinatal transmission of HIV]. MINERVA GINECOLOGICA 2007; 59:139-49. [PMID: 17505456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Paediatric HIV infection is still the most important pandemic, despite the substantial reductions of mother to child transmission achieved in North America and Europe. The total number of people living with the human immunodeficiency virus (HIV) rose in 2004 to reach its highest level ever: an estimated 39.4 million people are living with the virus. This number has been rising in every region, compared with two years ago, with the steepest increases occurring in East Asia, in Eastern Europe and central Asia. Sub-Saharan Africa remains by far the worst-affected region, with 25,4 million people living with HIV at the end of 2004. The AIDS epidemic is affecting women and girls in increasing number in Africa; them make up almost 57% of all people infected with HIV, but became a striking 76% in Sub-Saharan area. This review will focus on the current knowledge available regarding the timing of HIV transmission and the subsequent implications for its prevention. Mother to child transmission can take place during pregnancy, labour, delivery and post-partum, through breastfeeding. Different factors may influence HIV transmission during each of these time periods, and hence interventions to reduce transmission during each of these periods may also require different preventive strategies. The risk of mother to child transmission of HIV infection can be substantially reduced from 15-20% without interventions to less than 2% with the use of antiretroviral therapy during pregnancy, during labour and in the neonatal period, with an elective caesarean section delivery and refraining from breastfeeding. Factors associated with an increased risk of perinatal HIV transmission include advanced maternal blood, prolonged duration of ruptured membranes, and increased quantity of HIV in maternal blood at delivery.
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Abstract
The mTOR/S6K/4E-BP1 pathway integrates extracellular signals derived from growth factors, and intracellular signals, determined by the availability of nutrients like amino acids and glucose. Activation of this pathway requires inhibition of the tumor suppressor complex TSC1/2. TSC2 is a GTPase-activating protein for the small GTPase Ras homologue enriched in brain (Rheb), GTP loading of which activates mTOR by a yet unidentified mechanism. The level at which this pathway senses the availability of amino acids is unknown but is suggested to be at the level of TSC2. Here, we show that amino-acid depletion completely blocks insulin- and TPA-induced Rheb activation. This indicates that amino-acid sensing occurs upstream of Rheb. Despite this, amino-acid depletion can still inhibit mTOR/S6 kinase signaling in TSC2-/- fibroblasts. Since under these conditions Rheb-GTP levels remain high, a second level of amino-acid sensing exists, affecting mTOR activity in a Rheb-independent fashion.
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