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Biomedical subjects

P Borri

Publications and source records attributed to P Borri.

At least 19 recordsLinked to original sources
PubMed2003

Exciton dephasing in quantum dot molecules.

We have measured the exciton dephasing time in InAs/GaAs quantum dot molecules having different interdot barrier thicknesses in the temperature range from 5 to 60 K, using a highly sensitive four-wave mixing heterodyne technique. At 5 K dephasing times of several hundred picoseconds are found. Moreover, a systematic dependence of the dephasing dynamics on the barrier thickness is observed. These results show how the quantum-mechanical coupling of the electronic wave functions in the molecules affects both the exciton radiative lifetime and the exciton-acoustic phonon interaction.

Journal Article↗
PubMed2003

[Thin-layer cytology in endometrial diagnosis].

Our purpose was to test the liquid-based thin layer method on the endometrial cytology. One hundred sixty two consecutive patients before the hysterectomy (55 women because of various causes; 107 asymptomatic postmenopausal women because of prolapsed uterus) had the endometrial cytology (all women) and the biopsy (107 postmenopausal women prolapsed uterus affected). Cytohistologic concordance was 98%: all endometrial neoplasms and atypical hyperplasia (10 cases) and 15 of the 18 (83%) simple hyperplasias were diagnosed by thin layer endometrial cytology. In asymptomatic postmenopausal women cytology gave sufficient material for the diagnosis significantively more often than endometrial biopsy (respectively 82% and 24%; p = 0.000).

Adenocarcinoma↗
PubMed2002

Relaxation and dephasing of multiexcitons in semiconductor quantum dots.

We measure the dephasing time of ground-state excitonic transitions in InGaAs quantum dots under electrical injection in the temperature range from 10 to 70 K. Electrical injection into the barrier region results in a pure dephasing of the excitonic transitions. Once the injected carriers fill the electronic ground state, the biexciton to exciton transition is probed and a correlation of the exciton and biexciton phonon scattering mechanisms is found. Additional filling of the excited states creates multiexcitons that show a fast dephasing due to population relaxation.

Journal Article↗
PubMed2001

Ultralong dephasing time in InGaAs quantum dots.

We measure a dephasing time of several hundred picoseconds at low temperature in the ground-state transition of strongly confined InGaAs quantum dots, using a highly sensitive four-wave mixing technique. Between 7 and 100 K the polarization decay has two distinct components resulting in a non-Lorentzian line shape with a lifetime-limited zero-phonon line and a broadband from elastic exciton-acoustic phonon interactions.

Journal Article↗
PubMed2001

Longstanding survival without cancer progression in a patient affected by endometrial carcinoma treated primarily with leuprolide.

We report here a case of a patient affected by endometrial cancer and treated primarily with leuprolide, the surgical approach being unfeasible due to her compromised conditions. The therapy was continued for more than 6 years, and no progression of the disease was observed. During this period, some histological and immunohistochemical evaluations of the tumour (morphology, grading, proliferation and apoptotic index, E-cadherin expression) were performed. Furthermore, the expression of m-RNA for luteinizing-hormone releasing hormone (LHRH) receptors was determined. The results showed a discrepancy between some biological parameters of the tumour and its clinical characteristics. In fact, despite features suggestive of a progression of the cancer (such as the increase of both tumour grading and proliferating capacity (MIB-1), and a fall in the reparative process (appearance of mutated p53, reduced expression of both bcl-2 and c-erb-2) being detected, neither local invasion nor metastatic lesions were clinically observed. This discrepancy might be due to the maintenance of high levels of E-cadhezin. Moreover, since this tumour was shown to express mRNA for LHRH receptors, new evidence is provided about the favourable impact of LHRH analogue treatment in patients affected by endometrial cancer.

Adenocarcinoma↗
PubMed2001

Ageing of the human oviduct: lectin histochemistry.

The aim of the present research was to investigate the changes of the sugar residues in the oviduct in the course of ageing in postmenopausal women vs normally menstruating women, by means of lectin histochemistry. Twenty asymptomatic postmenopausal women (48-83 years old) were recruited among patients who underwent a vaginal hysterectomy. Eight normally menstruating women were recruited as controls. Fragments of Fallopian tubes (pars ampullaris) were fixed in 10% formalin and routinely processed. The sections were labelled with HRP-lectins (PNA, SBA, DBA, WGA, Con A, LTA, UEAI). Some sections were pre-treated with neuraminidase prior to staining with HRP-lectins. Among the postmenopausal patients, our histochemical data showed that there was no difference in the localization and distribution of sugar residues of glycoconjugates as detected by various HRP-lectins. Moreover, our results demonstrated that the oviductal epithelium is characterized by apical reactivity in both ciliated and non-ciliated cells. In the course of ageing, the ciliated cells changed their morphology from bathyprismatic to large and rounded shape. ConA lectin reacted intensely with such highly degenerating ciliated cells and could be considered a marker of these cells. The degenerating ciliated cells are also characterized by the absence of sialic acid. In comparison with the sugar residues present in the control group, the oviductal epithelium of postmenopausal women is characterized by the loss of reactivity with DBA, WGA and ConA. Moreover, PNA reactive material was present at the free border of the ciliated and non-ciliated cells. The latter findings were statistically confirmed and could be considered strictly related to the ageing process.

Aged↗
PubMed2000

Inhibitory effect of luteinising hormone-releasing hormone analogues on human endometrial cancer in vitro.

We studied the effects of luteinising hormone-releasing hormone (LHRH) agonist leuproreline (1 microM for 96 h) and LHRH antagonist cetrorelix on the cell growth of primary cultures from nine human endometrial cancers using the sulphorhodamine colorimetric test. Histological examinations and reverse transcription and polymerase chain reaction amplification (RT-PCR) for LHRH receptors were also performed. The endometrial cancers examined had a medium to high degree of proliferative activity and a low degree of apoptotic power; furthermore, they expressed the LHRH receptor RNA variably, detectable in 71% of cases. The addition of leuproreline or cetrorelix to cell cultures inhibited growth in a statistically significant way compared to untreated control cells; nevertheless, the percentage of cell growth inhibition obtained was very variable. These data suggest that LHRH analogues can exert differential inhibitory effects on the growth of endometrial cancer, which seems to be independent of the expression of specific LHRH receptors.

Aged↗
PubMed2000

HERG potassium channels are more frequently expressed in human endometrial cancer as compared to non-cancerous endometrium.

HERG K(+)channels, besides contributing to regulate cardiac and neuronal excitability, are preferentially expressed in tumour cell lines of different histogenesis, where their role in the development and maintenance of the neoplastic phenotype is under study. We show here that both herg gene and HERG protein are expressed with high frequency in primary human endometrial cancers, as compared to normal and hyperplastic endometrium. RT-PCR and immunohistochemistry, using specific anti-HERG antibodies developed in our laboratory, were applied to tissue specimens obtained from 18 endometrial cancers and 11 non-cancerous endometrial tissues. herg RNA and HERG protein are expressed in 67% and 82%, respectively, of cancerous, while in only 18% of non-cancerous tissues. In particular, no expression was found in endometrial hyperplasia. Moreover, electrophysiological experiments confirmed the presence of functioning HERG channels on the plasma membrane of tumour cells. On the whole, these data are the first demonstration of the presence of HERG channels in primary human neoplasias, and could candidate HERG as a potential tool capable of marking cancerous versus hyperplastic endometrial growth.

Aged↗
PubMed1998

Differential inhibitory effects on human endometrial carcinoma cell growth of luteinizing hormone-releasing hormone analogues.

In addition to its function as a key hormone in the regulation of the pituitary-gonadal axis, luteinizing hormone-releasing hormone (LHRH) probably also affects various extrapituitary tissues. LHRH binding sites and in vitro antiproliferative effects of LHRH analogues have been reported in human endometrial cancer. The effects of the LHRH agonist leuproreline and LHRH antagonist antide were studied on the cell growth, DNA synthesis, and cell cycle distribution of the human endometrial cancer cell lines HEC-1A and HEC-1B by the sulforhodamine B (SRB) method, [3H]thymidine assay incorporation, and propidium iodide DNA staining, respectively. In the presence of 1.0-100 microM leuproreline the proliferation of HEC-1A cells was significantly reduced as early as 3 days after drug exposure, with a minimum growth value of 69.9 +/- 3.6% (mean +/- SE) at the highest concentration tested (100 microM). Similar antiproliferative effects were obtained following a 6-day treatment with the LHRH antagonist antide. Also, inhibitory effects on [3H]thymidine incorporation into the DNA of the HEC-1A cell line were noted after a 6-day exposure to both LHRH analogues, in the above-mentioned concentration range. Cell cycle analysis of HEC-1A cells cultured in the presence of 10 microM leuproreline and antide showed a slight accumulation of cells in the G0/G1 phase, while the proportions of cells in the S and G2/M phases concomitantly decreased. No significant effects on proliferation, DNA synthesis, and cell cycle distribution were observed in HEC-1B cells with either leuproreline or antide (up to 100 and 10 microM, respectively) after a 6-day exposure. Both Northern blot analysis and reverse transcription polymerase chain reaction failed to detect expression of mRNA for the LHRH receptor in both HEC-1A and HEC-1B cell lines. In addition, the LHRH analogues did not affect the intracellular free calcium concentration, indicating that the classic signal transduction for LHRH is absent or impaired in HEC-1A cells. The observed direct inhibitory actions on HEC-1A cells support the concept that the two LHRH analogues may exert biological effects via cellular effectors distinct from the "classic" LHRH receptor. Although the mechanism by which these direct actions are produced is still obscure, these results might help to establish the basis for new approaches to the therapy of endometrial cancer.

Antineoplastic Agents, Hormonal↗
PubMed1998

The ovary is not a major source of placental protein 14 (glycodelin).

Placental protein 14 (PP14) is the major glycoprotein synthesized by late secretory endometrium and gestational decidua. The control mechanisms of PP14 production are uncertain but might include progesterone or an ovarian factor. It has been suggested that PP14 might be produced by the ovary itself. The aim of the present study was to evaluate if the ovary is a major source of PP14. We measured PP14 and also insulin-like growth factor binding protein-1 (IGFBP-1), another protein produced in large amounts by the secretory endometrium though not specific to that tissue. The samples included sera from the ovarian vein in one subject, sera of three women affected with Rokitansky syndrome (absent uterus) and follicular fluid samples collected during oocyte recovery in 46 in-vitro fertilization patients. PP14 was undetectable in the sample collected from the ovarian vein at the mid-luteal phase and was absent or at very low concentrations in most of the follicular fluid samples. Furthermore, the predominantly uterine origin was confirmed by the inability to detect any PP14 in sera throughout the menstrual cycle from patients with congenital absence of the uterus (Rokitansky syndrome). In conclusion this study shows that the ovary is not a major source of PP14.

Adult↗
PubMed1998

Lectin binding in the human endometrium in early luteal phase following controlled ovarian hyperstimulation.

A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties on the endometrial epithelium and stroma in 12 women undergoing controlled ovarian hyperstimulation (COH) for in-vitro fertilisation for embryo transfer (IVF-ET) in early luteal phase. 7 control subjects were also evaluated. For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. Cytochemical controls were performed for specificity of lectin-sugar reaction. As far as the endometrial glands and stroma are concerned, the obtained data showed no differences in the endometrial lectin binding between the subjects of the control group and the ones undergoing COH, with the exception of PNA reactivity at the level of the apical portion of the glandular cells, which was detected only in COH women. It is noteworthy that, although the endometrial dating using the Noyes's criteria showed marked dissynchronies between the stroma and the glands in COH subjects, a uniformity of lectin binding, revealing the same type and localization of terminal oligosaccharides, was observed in all the examined subjects. The uniformity in distribution of the sugar residues detected in the endometrial specimens following COH might be due to the massive FSH and/or hCG treatment which probably determines an endometrial environment almost equal in all the examined subjects. In all the treated subjects reactivity with sialidase-WGA and ConA, revealing the presence of N-acetyl-D-glucosamine and D-mannose respectively, was detected at the level of the lining epithelium.

Adult↗
PubMed1997

Hormonal patterns, steroid receptors and morphological pictures of endometrium in hyperstimulated IVF cycles.

OBJECTIVE: The purpose of this contribution is to investigate the pathophysiology of the abnormal endometrial development in hyperstimulated IVF cycles. STUDY DESIGN: In 12 IVF-patients who did not have embryo transfer because of failure of oocyte fertilization, serum values of 17 beta-estradiol, progesterone, FSH, LH, total and free testosterone, and androstenedione were measured on the pick-up day and were evaluated with respect to the values normally expressed in the day of ovulation; in the endometrial specimens collected 2 days later, at the time of embryo replacement, estrogen and progesterone receptors were immunohistochemically determined and dating by the Noyes method was performed. RESULTS: 17 beta-Estradiol values are constantly higher, and progesterone levels are, only in four cases, higher than expected for the day of ovulation in a natural cycle. These hormonal patterns can only partially explain the pattern of steroid receptors: progesterone receptors are expressed sparsely both in glands and stroma, while estrogen receptors are abundant in the glands and absent in the stroma. In 11 of 12 patients an abnormal endometrial development with stromal advancement was observed: this morphological picture of the endometrium could partially be explained only in the four cases presenting high progesterone levels by serum values and endometrial receptor content of estrogen and progesterone. CONCLUSIONS: The abnormal endometrial development in hyperstimulated IVF cycles could only in part be explained by estrogen and progesterone, and other factors have to be considered.

Androstenedione↗
PubMed1997

Human endometrial cancers contain follicle-stimulating hormone receptors: a preliminary study.

In order to investigate whether human endometrial cancers contain follicle-stimulating hormone (FSH) receptors, cancer fragments were collected at hysterectomy in six post-menopausal women affected by histologically confirmed endometrial malignancy. Cryostat sections were prepared for in situ binding investigation. Positive endometrial glandular cells were registered in all cancers; 125I-FSH binding sites seemed to increase with the increasing tumor grade. Our data demonstrated for the first time that human endometrial cancers contain specific FSH receptors.

Aged↗
PubMed1996

Aging of the human endometrium: peri-implantation phase endometrium does not show any age-dependent variation in lectin binding.

OBJECTIVE: To evaluate if the peri-implantation endometrium shows age variations in lectin patterns, which suggest possible age variations in embryo-maternal recognition. STUDY DESIGN: Peri-implantation endometria of younger ( < 30 years of age: n = 13) and older ( > 40 years of age: n = 17) normally menstruating women was studied. Endometrial specimens were routinely fixed in buffered formaline and embedded in paraffin. Sections (5 microns) were studied using seven lectins: DBA (Dolicus biflorus, binding specificity alpha-D-GalNAc), PNA (Arachis hypogea, binding specificity D-Gal (beta 1 --> 3)-D-GalNAc), SBA (Glycine max binding specificity alpha/beta-D-GalNAc > D-Gal), WGA (Triticum vulgare binding specificity (alpha-D-GlcNAc)n and sialic acid), ConA (Canavalia ensiformis binding specificity alpha-D-Man > alpha-D-Glc), LTA (Lotus tetragonolobus binding specificity alpha-L-fucose) and UEA 1 (Ulex europaeus binding specificity alpha-L-fucose). RESULTS: No significant differences were found in the glycoconjugates sugar residue content and distribution between the endometria of women < 30 years of age and those of women > 40. CONCLUSIONS: Our results suggest that human endometrium does not age, at least while cyclic hormonal stimulation and menstruation are present.

Adult↗
PubMed1996

Morphological and functional aspects of the endometrium of asymptomatic post-menopausal women: does the endometrium really age?

The morphological and functional aspects of the endometrium were investigated in 28 asymptomatic post-menopausal women to evaluate the ageing phenomenon of this tissue. Haematoxylin-eosin staining showed an atrophic endometrium in 12 cases and a hyperplastic endometrium in the other 16 cases. Masson's trichrome identified moderate fibrosis in all post-menopausal endometrial stroma. Immunohistochemical analyses were performed on the endometrial specimens to evaluate the distribution of the capillary system, the cellular proliferation index and the presence of oestrogen and progesterone receptors. Our data showed a discrepancy between the morphological pictures and the functional aspects of the post-menopausal endometrium. In fact, the morphological pictures suggested an involution of this tissue according to the increase in collagen fibres, the decrease in vascular distribution and the frequent atrophic patterns. On the other hand, data from steroid receptors and the cell proliferation index suggest that post-menopausal endometrium is an active structure. So, endometria from normal post-menopausal women appear to be in a more quiescent state than in a really atrophic condition. This leads to the question: does the endometrium really age?

Aged↗
PubMed1996

Chorion villosum does not express progesterone and estrogen receptors during the first trimester of pregnancy.

First-trimester chorion villosum plays the key role in the development of human placenta and secretes a large number of hormones and hormone-related substances. To test whether progesterone and estrogen could have regulatory effects on first-trimester chorion villosum functions, we investigated the presence of progesterone receptor (PR) and estrogen receptor (ER) in 47 chorion villosum samples from patients who underwent abortion during the first trimester of pregnancy. The study was carried out using immunohistochemical methods. No ER and PR positivity was evidenced in the 47 chorion villosum samples examined. The possibility that progesterone and estrogen play a role in the regulation of chorion villosum functions should therefore be excluded.

Antibodies, Monoclonal↗
PubMed1996

CA125 in culture medium of preimplantation embryo.

The first stage of the implantation is the adhesion of the embryonic pole of the blastocyst to the decidua. Such a phenomenon has been demonstrated to be dependent on the presence of glycoproteic compounds, produced partly by the decidua and partly by the embryo. CA125 is an antigenic determinant associated to a glycoprotein expressed by various embryonic tissues. The objective of our research has been to measure the production of CA125 by the embryo in the initial phase of its development. Patients were recruited from our in vitro fertilization program. The culture medium used for the oocytes and for the embryos was collected and CA125 levels were measured. The results indicate that there is not a statistically significative difference between the values of CA125 measured in the mediums where a pronucleus or an embryo was present and the negative controls. From our data, therefore, it can be concluded that CA125 expression begins later in the human embryonic development than 8-cells-stage embryo.

Blastocyst↗