Alexandros Daponte

Prof. Dr. Alexandros Daponte

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Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 March 2023 in Cancers
Verified
Journal Article
Open access
PDF file
NDNikoletta Daponte
Nikoletta Daponte
George ValasoulisGeorge Valasoulis
George Valasoulis
GMGeorgios Michail
Georgios Michail
IMIoulia Magaliou
Ioulia Magaliou
Athina - Ioanna DaponteAthina - Ioanna Daponte
Athina - Ioanna Daponte
ADAlexandros Daponte
Alexandros Daponte
Identifying and reaching women at higher risk for cervical cancer is all-important for achieving the ambitious endpoints set in 2020 by the WHO for global cervical cancer control by 2030. HPV-based (vaginal) self-sampling (SS) represents a cost-effective screening strategy, which has been successfully implemented during the last decade both in affluent and constrained settings. Among other advantages, SS strategies offer convenience, diminished costs, flexibility to obtain a sample in the office or home, avoiding a pelvic exam and uncomfortable appointment with a healthcare professional, as well as social and cultural acceptability. SS implementation has been globally boosted during the COVID-19 pandemic. In pragmatic terms, social distancing, local lockdowns, discontinuation of clinics and reallocation of human and financial resources challenged established clinician-based screening; self-collection strategies apparently surpassed most obstacles, representing a viable and flexible alternative. With time, sufficient reassuring data has accumulated regarding specially designed SS devices, aspects of sample preparation, transport and storage and, importantly, optimization of validated PCR-based HPV testing platforms for self-collected specimens. Suboptimal rates of clinical follow-up post-SS screening, as well as overtreatment with reliance solely on molecular assays, have both been documented and remain concerning. Therefore, effective strategies are still required to ensure linkage to follow-up testing and management following positive SS results by trained health professionals with knowledge of HPV biology and management algorithms. Because of the prolonged SS screening intervals, implementation data are limited regarding subsequent screening rounds of SS-screened individuals; however, these are accumulating gradually. With further refinement of assays and validation of novel biomarkers in self-collected samples, there is a clear potential for increasing SS accuracy and PPV. The potential differentiation of self-collection protocols for vaccinated versus non-vaccinated individuals also represents an open issue. In conclusion, HPV-based self-collection techniques can effectively address limited uptake alongside other conventional cervical screening drawbacks; however, assays, logistics and infrastructures need further optimization to increase the efficacy, effectiveness and cost-effectiveness of SS approaches.

George AnifandisGeorge Anifandis
George Anifandis
KKKaterina Katsanaki
Katerina Katsanaki
GLGeorgia Lagodonti
Georgia Lagodonti
CMChristina I. Messini
Christina I. Messini
Mara SimopoulouMara Simopoulou
Mara Simopoulou
ADAlexandros Daponte
Alexandros Daponte
Glyphosate is the active ingredient of Roundup®, which is one of the most popular herbicides worldwide. Although many studies have focused on the reproductive toxicity of glyphosate or glyphosate-based herbicides, the majority of them have concluded that the effect of the specific herbicide is negligible, while only a few studies indicate the male reproductive toxicity of glyphosate alone. The aim of the present study was to investigate the effect of 0.36 mg/L glyphosate on sperm motility and sperm DNA fragmentation (SDF). Thirty healthy men volunteered to undergo semen analysis for the purpose of the study. Sperm motility was calculated according to WHO 2010 guidelines at collection time (zero time) and 1 h post-treatment with glyphosate. Sperm DNA fragmentation was evaluated with Halosperm® G2 kit for both the control and glyphosate-treated sperm samples. Sperm progressive motility of glyphosate-treated samples was significantly reduced after 1 h post-treatment in comparison to the respective controls, in contrast to the SDF of glyphosate-treated samples, which was comparable to the respective controls. Conclusively, under these in vitro conditions, at high concentrations that greatly exceed environmental exposures, glyphosate exerts toxic effects on sperm progressive motility but not on sperm DNA integrity, meaning that the toxic effect is limited only to motility, at least in the first hour.

26 September 2018 in Advances in Medicine
Verified
Journal Article
Open access
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DCDimitra Charatsi
Dimitra Charatsi
OKOurania Koukoura
Ourania Koukoura
INIrontianta Gkorezi Ntavela
Irontianta Gkorezi Ntavela
FCFoteini Chintziou
Foteini Chintziou
GGGeorgia Gkorila
Georgia Gkorila
ADAlexandros Daponte
Alexandros Daponte
Extrapelvic endometriosis is a rare entity that presents serious challenges to researchers and clinicians. Endometriotic lesions have been reported in every part of the female human body and in some instances in males. Organs that are close to the uterus are more often affected than distant locations. Extrapelvic endometriosis affects a slightly older population of women than pelvic endometriosis. This might lead to the assumption that it takes several years for pelvic endometriosis to “metastasize” outside the pelvis. All current theories of the pathophysiology of endometriosis apply to some extent to the different types of extrapelvic endometriosis. The gastrointestinal tract is the most common location of extrapelvic endometriosis with the urinary system being the second one. However, since sigmoid colon, rectum, and bladder are pelvic organs, extragenital pelvic endometriosis may be a more suitable definition for endometriotic implants related to these organs than extrapelvic endometriosis. The sigmoid colon is the most commonly involved, followed by the rectum, ileum, appendix, and caecum. Most lesions are confined in the serosal layer; however, deeper lesion can alter bowel function and cause symptoms. Bladder and ureteral involvement are the most common sites concerning the urinary system. Unfortunately, ureteral endometriosis is often asymptomatic leading to silent obstructive uropathy and renal failure. Surgical excision of the endometriotic tissue is the ideal treatment for all types of extrapelvic endometriosis. Adjunctive treatment might be useful in selected cases.

21 December 2017 in Toxics
Verified
Journal Article
Open access
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GAGeorgios S Amiridis
Georgios S Amiridis
GAGeorgios S Amiridis
Georgios S Amiridis
KDKonstantinos Dafopoulos
Konstantinos Dafopoulos
ADAlexandros Daponte
Alexandros Daponte
EDEleni Dovolou
Eleni Dovolou
Anna-Maria G. PsarraAnna-Maria G. Psarra
Anna-Maria G. Psarra
Toxicants, such as herbicides, have been hypothesized to affect sperm parameters. The most common method of exposure to herbicides is through spraying or diet. The aim of the present study was to investigate the effect of direct exposure of sperm to 1 mg/L of the herbicide Roundup on sperm motility and mitochondrial integrity. Sperm samples from 66 healthy men who were seeking semen analysis were investigated after written informed consent was taken. Semen analysis was performed according to the World Health Organization guidelines (WHO, 2010). Mitochondrial integrity was assessed through mitochondrial staining using a mitochondria-specific dye, which is exclusively incorporated into functionally active mitochondria. A quantity of 1 mg/L of Roundup was found to exert a deleterious effect on sperm’s progressive motility, after 1 h of incubation (mean difference between treated and control samples = 11.2%) in comparison with the effect after three hours of incubation (mean difference = 6.33%, p < 0.05), while the relative incorporation of the mitochondrial dye in mitochondria of the mid-piece region of Roundup-treated spermatozoa was significantly reduced compared to relative controls at the first hour of incubation, indicating mitochondrial dysfunction by Roundup. Our results indicate that the direct exposure of semen samples to the active constituent of the herbicide Roundup at the relatively low concentration of 1 mg/L has adverse effects on sperm motility, and this may be related to the observed reduction in mitochondrial staining.

16 November 2008 in BMC Cancer
Verified
Journal Article
Open access
PDF file
ADAlexandros Daponte
Alexandros Daponte
MIMaria Ioannou
Maria Ioannou
IMIlias Mylonis
Ilias Mylonis
George SimosGeorge Simos
George Simos
MMMarcos Minas
Marcos Minas
GKGeorge Koukoulis
George Koukoulis
The hypoxia-inducible factor (HIF) has emerged as an attractive target for cancer therapy. The few publications addressing the prognostic significance of Hypoxia-Inducible Factor 1α (HIF-1α) cellular expression in ovarian cancer produced contradictory findings which are not permissible to widely acceptable conclusions and clinical applications. Our study was designed to investigate this by including a comparatively large number of cases and by using a combination of antibodies to analyze immunohistochemically the expression of HIF-1α. One hundred (n = 100) neoplastic and 20 benign (controls) pathological samples from paraffin-embedded tissue were included. They were classified after surgery as stage I (n = 23) and stage III G3 (n = 55). Also 22 borderline serous adenocarcinoma patients and 20 benign controls were stained. The mean follow up was 3 years. Only patients with the diagnosis of serous carcinoma of stage III, G3 who received 6 cycles of postoperative TC (175–180 mg/m2 paclitaxel and carboplatin after calculating the area under the concentration curve) with complete medical records (n = 55) were selected for survival analysis. The survival analysis of the samples compared two groups after the patients were dichotomized by HIF-1α final score to positive and negative. The frequency of the nuclear expression of HIF-1α in benign tumours was significantly lower (median: no expression) than in borderline and ovarian cancer tumours combined (p < 0.001). HIF-1α expression in serous ovarian carcinoma was not stage dependent. The overall survival of patients with tumours that stained strongly for HIF-1α was significantly shorter than that of patients with tumours that stained weakly or were negative for HIF-1α (p = 0.01). Kaplan-Meier survival curves confirmed that HIF-1α "positive" had decreased overall survival compared to HIF-1α "negative" patients (p = 0.003) and this was an independent adverse prognostic factor (multivariable analysis p = 0.006). HIF-1α "positive" patients displayed a shorter median progress free interval (PFI) (not statistically significant p > 0.05). Interestingly the overall PFI of the subgroup of patients that have undergone suboptimal cytoreduction at primary surgery (n = 21) with tumours that stained strongly for HIF-1α was significantly worse than that of patients with tumours that stained weakly or were negative for HIF-1α (p = 0.03). Our report confirms the prognostic value of HIF-1α when restricted to poorly differentiated serous ovarian carcinoma. In addition it shows that this association is elusive, since it is not only methodology-related but it can be antibody-depended. There is adequate evidence to speculate that targeting HIF-1α could improve the long-term prognosis of these patients In order to increase the overall sensitivity of the immunoassay, maintaining acceptable levels of specificity, a panel of antibodies should be used.

1 May 2006 in Fertility and Sterility
Verified
Journal Article
Closed access
ADAlexandros Daponte
Alexandros Daponte
SPSpyros Pournaras
Spyros Pournaras
Christos HadjichristodoulouChristos Hadjichristodoulou
Christos Hadjichristodoulou
GLGeorgios Lialios
Georgios Lialios
AKAthanasios Kallitsaris
Athanasios Kallitsaris
IMIoannis E. Messinis
Ioannis E. Messinis