Biomedical subjects

G Berger

Publications and source records attributed to G Berger.

At least 37 records · Page 2Linked to original sources

PubMed2001

The human ABCG4 gene is regulated by oxysterols and retinoids in monocyte-derived macrophages.

Here we report the induction of gene expression of ABCG4, a member of the ABC transporter subfamily G, from human macrophages by oxysterols and retinoids, agonists of the nuclear receptors LXR and RXR. The cloned ABCG4 transcript has a size of 3.5 kb and contains an open reading frame which encodes a polypeptide of 646 amino acids. Structurally, the putative ABC transporter protein consists of a nucleotide binding fold followed by a cluster of six transmembrane-spanning domains and thus conforms to the group of half-size ABC transporters. Among the human ABC transporter subfamily G members the novel transporter shows highest protein sequence homology and identity to ABCG1 (84 and 72%, respectively). Analysis of the genomic organization demonstrates that the ABCG4 gene is composed of at least 14 exons which extend across a region of 12.6 kb in size on chromosome 11q23.3. Based on its structural features and an LXR/RXR-responsive regulation similar to the cellular lipid export protein ABCA1, we conclude that ABCG4 may be involved in macrophage lipid homeostasis.

ATP Binding Cassette Transporter, Subfamily G↗

PubMed2001

Laser-assisted uvulopalatoplasty for snoring: medium- to long-term subjective and objective analysis.

OBJECTIVE: To assess the subjective and objective medium- to long-term results of laser-assisted uvulopalatoplasty for snoring. DESIGN: A nonrandomized, prospective, before-after trial. SUBJECTS AND INTERVENTIONS: Fourteen patients underwent laser-assisted uvulopalatoplasty surgery; 2 surgical techniques, which differ with respect to the mode of midline palatal vaporization, were used. MAIN OUTCOME MEASURES: Subjective analysis included a preoperative and 2 postoperative evaluations of the state of snoring: 4 weeks and 10.1 +/- 7.9 months (mean +/- SD) after completion of last laser treatment. In addition, a score on 5 other sleep-related symptoms was recorded before treatment and after 10.1 +/- 7.9 months; at that time, patients also estimated their overall satisfaction with the procedure. Objective analysis included preoperative nocturnal polysomnographic studies that were repeated postoperatively. RESULTS: A decline in snoring improvement from 79% (11/14) to 57% (8/14) was recorded; furthermore, state of snoring worsened from 7% (1/14) to 21% (3/14). Likewise, reevaluation of the 5 other sleep-related symptoms at the final follow-up visit uncovered a 57% improvement rate. Overall satisfaction with the procedure was 43%. The results of the postoperative objective studies corresponded to those of the subjective ones and demonstrated significant worsening of respiratory disturbance index in 3 (21%) of the 14 patients, who became mildly apneic. These findings were encountered with both laser techniques. CONCLUSIONS: The favorable subjective short-term results of laser-assisted uvulopalatoplasty deteriorated with time. In addition, postoperative nocturnal polysomnography showed that the procedure caused mild obstructive sleep apnea in a considerable number of patients who formerly were nonapneic snorers. These findings may be related to velopharyngeal narrowing and progressive palatal fibrosis, caused by the thermal damage inflicted by the laser beam.

Adult↗

PubMed2001

Reproducibility of skin characterization with backscattered spectra (12--25 MHz) in healthy subjects.

Ultrasonic techniques were developed for quantitative in vivo analysis of skin composition based on measurements of apparent integrated backscatter (IBS) and its frequency dependence (n) between 12.5 and 25 MHz. Parameters were measured at five depths in healthy dermis of the midforearm of 29 volunteers (13 women, 16 men, 20 to 76 years old) on three different days. Reproducibility of measurements was evaluated (standardized coefficients of variation: 7% to 11% for IBS and 9% to 20% for n). Parameter values were significantly influenced by pressure of the ultrasonic probe on the skin, and both room and skin-surface temperatures were correlated to IBS measured in a single subject on 28 days. More precise control of these factors could further improve measurement reproducibility and sensitivity to skin composition. Significant (p < 0.05) differences of parameter values with respect to region of interest depth, age and gender of subjects were discussed in comparison with dermal composition and offer promise that these parameters could be used to characterize skin modifications.

Adult↗

PubMed2001

Quantification of ultrasound contrast agent response: comparison of continuous wave Doppler and power Doppler to backscattered radiofrequency data.

Our goal was to compare two quantification methods of ultrasound contrast agents available in clinical practice [continuous wave Doppler intensity (CWDI) and power Doppler intensity (PWDI)] to the reference technique (radio-frequency analysis) with a simple recirculating flow phantom using a renal dialysis cartridge. Measurements were made at different doses of perflenapent emulsion and BR1. Cineloops of power Doppler images were recorded using a clinically available ultrasound unit (HDI 3000). Simultaneously, integrated backscatter (IBS) was measured by analysis of radiofrequency signals, whereas Doppler signal intensity was measured with a continuous wave Doppler device. A linear relationship was found between CWDI and IBS and between PWDI and IBS when R(2) was calculated for each pair of parameters injection-by-injection. Results are summarized by the average R(2) for all injections between CWDI and IBS (BR1: R(2) = 0.93 +/- 0.05, perflenapent emulsion: R(2) = 0.94 +/- 0.03) and between PWDI and IBS (BR1: R(2) = 0.88 +/- 0.07, perflenapent emulsion: R(2) = 0.79 +/- 0.09). However, for all data obtained from all different injected doses and for both contrast agents, there was considerable variation of CWDI and PWDI values measured for a given value of IBS. In conclusion, for a fixed microbubble population, CWDI and PWDI can be proposed for quantification of USCA. However, their important variations observed at each dose make it difficult to link a single value of PWDI or CWDI or IBS to a single microbubble distribution composition.

Contrast Media↗

PubMed2001

Comparison of different cations (Mn2+, Mg2+, Ca2+) on the hydrolytic activity of chloroplast ATPase.

The influences of Mn2+, Mg2+, and Ca2+ on the enzymic activity of chloroplast ATPase have been compared, using an HPLC method for the separation of ADP. The dissociation constants of the divalent ion-ATP complexes have been determined by a spectrophotometric method, with the dye antipyrylazo III, and enzymic constants (dissociation constant of the ion-enzyme complexes, Michaelis constants, maximum rates) have been calculated. The comparison between the rates obtained, respectively, with Mn2+ and Ca2+ alone with that given by the mixture of these two ions, allows us to conclude that, as for Mg2+, Mn2+ is also an activator of chloroplast ATPase and that metal-free ATP is the true substrate.

Adenosine Triphosphate↗

PubMed2001

Increased apoptosis in mononucleated cells but not in CD34+ cells in blastic forms of myelodysplastic syndromes.

INTRODUCTION: Myelodysplastic syndromes are characterized by peripheral refractory cytopenias together with normo or hyper cellular marrow. Increased apoptosis has been shown to be involved in the process leading to this paradox. MATERIALS AND METHODS: Early apoptosis detection, based on the modification of mitochondrial transmembrane potential (deltapsim), was performed on bone marrow cells from 42 MDS patients (21 RA, four RARS, 10 RAEB, two RAEB-t, three sAML, and two CMML) and seven normal healthy donors. Phosphatidylserine (PS) expression, a late/intermediate marker of the apoptotic cascade, was also quantified. Apoptosis was analysed by flow cytometry both on unsorted mononuclear cells and on progenitor cells after CD34+ magnetic cell sorting. RESULTS: A significant increase of apoptosis of MNC was observed in RA, RARS, RAEB and to a lower extent in RAEB-t and AML samples. In the progenitor compartment, RA and RARS samples presented a high level of apoptosis, whereas a switch to a low level of apoptosis was detected in the blastic forms RAEB, RAEB-t and sAML. Fas (CD95/APO-1), a member of the death domain receptor family, has been reported to be overexpressed on MDS CD34+ marrow cells. A functional assay of Fas cross-linking using the CH11 antibody on CD34+ marrow cells was performed on samples of 17 MDS patients; 8/17 were found to be sensitive to Fas-induced apoptosis. However, no correlation was observed with the level of in vivo spontaneous apoptosis. CONCLUSION: This study demonstrates increased apoptosis of MNC in all MDS subgroups as measured by deltapsim collapse. Moreover, while important apoptosis is still observed at the progenitor level in early MDS, blastic forms show a clear reduction of apoptosis. Study of Fas functionality modulates the implication of this receptor in the pathophysiology of the disease.

Adult↗

PubMed2001

Assessment of rat articular cartilage maturation using 50-MHz quantitative ultrasonography.

OBJECTIVE: The objective was to assess the relationship between maturation-related structural changes of articular cartilage and variations of acoustic parameters estimated using high frequency ultrasonography. DESIGN: Patellae taken from 48 immature Wistar male rats and divided into six age groups (from five to 11 weeks old) were explored in vitro using 50-MHz scanning acoustic microscopy, then assessed by histology for the analysis of the cartilage cell distribution and fibrillar collagen organization. The variation of cartilage proteoglycan and collagen content with age was evaluated. Thickness measurements performed on both B-scan images and histologic sections were compared. Ultrasonic radiofrequency signals reflected by the cartilage surface and backscattered from its internal matrix were processed to estimate the integrated reflection coefficient (IRC) and apparent integrated backscatter (AIB). RESULTS: One-way ANOVA indicated that acoustic parameters and thickness change significantly (P < 0.05) as the animal matures because of age-related changes in cartilage composition and morphology. A moderate correlation was found between IRC and the animal age. The parameter decreased slightly but significantly over time. However, a good correlation was observed between the rat age and the AIB, which decreased significantly over time. The parameter variation was mostly related to the changes in collagen fiber orientation, and/or to a change in cell size, density and organization. CONCLUSIONS: Current results indicate that acoustic properties of cartilage are affected by maturation-related cartilage changes. This suggests that high frequency ultrasonography may serve as a useful means for the investigation of cartilage matrix structural changes occurring under various clinical circumstances, like those observed during osteoarthritis, and for the evaluation of the efficacy of specific therapeutics.

Aging↗

PubMed2001

Long-term histologic effects of inferior turbinate laser surgery.

OBJECTIVE: In this study we sought to define the histologic changes produced by laser treatment of inferior turbinates. STUDY DESIGN: Eight inferior turbinates with prior laser treatment (mean, 26.8 months) were analyzed by light microscopy after turbinectomy for relief of refractory nasal obstruction. Histologic findings were compared with those of a group of 8 hypertrophic inferior turbinates that had no previous laser surgery. RESULTS: Laser-treated areas of the inferior turbinates demonstrated a histologically bland appearance, with marked diminution of seromucinous glands and relative preponderance of connective tissue matrix. Prominence of venous sinusoids was also significantly reduced in the laser-treated areas. Surface epithelium including goblet cells was reconstituted over the areas of laser application. CONCLUSION: Clinical laser surgery of the inferior turbinate produces striking long-term histologic changes. SIGNIFICANCE: The data suggest a differential response of turbinate histologic components to application of laser energy, with the glandular component being particularly sensitive. Further correlative study is needed to clarify the clinical significance of laser-induced histologic changes in inferior turbinates.

Adolescent↗

PubMed2001

Frontal and lateral cephalometry in patients with sleep-disordered breathing.

OBJECTIVES/HYPOTHESIS: The traditional lateral-view cephalometric analysis is limited because it provides only two-dimensional analysis of the three-dimensional craniofacial structure. The objectives were to analyze lateral and frontal cephalometric radiographs in a series of normal patients and those with varying degrees of sleep-disordered breathing and to define the degrees of narrowing or other unfavorable anatomical changes that might differentiate the patients with sleep-disordered breathing from normal subjects. STUDY DESIGN: A prospective study of 100 adult patients with sleep-disordered breathing and 60 age-matched normal subjects. METHODS: An analysis of the lateral and frontal cephalometric measurements was performed to assess velopharyngeal anatomical features. A comparison was made between the patients' polysomnographic and cephalometric analyses. RESULTS: The compromised cephalometric parameters that may be found in patients with sleep-disordered breathing include acute skull-base and bony nasopharynx angles, inferior hyoid position, thickening of the velum, reduced retrovelar posterior air space along with thickening of the velum, thickening of the posterior pharyngeal wall, and narrowing of the velopharyngeal lumen. Worsening of sleep-disordered breathing was generally associated with increased numbers of compromised cephalometric parameters. As body mass index increases, there is reduced velopharyngeal width, the velum thickness is increased, and the posterior pharyngeal wall thickness is increased. CONCLUSIONS: Sleep-disordered breathing is associated with statistically significant changes in a number of cephalometric measurements. Frontal cephalometric analysis adds further information regarding the anatomical assessment of patients with upper airway obstruction, enhancing the traditional lateral cephalometric view.

Body Mass Index↗

PubMed2001

Neuroendocrine differentiation is a relevant prognostic factor in stage III-IV colorectal cancer.

OBJECTIVE: To determine the prognostic relevance of neuroendocrine differentiation in colorectal cancer. METHODS: The survival of 116 patients with colorectal cancer of stages III (n = 59) and IV (n = 57) was correlated with the extent of neuroendocrine differentiation. Chromogranin A and synaptophysin were used as neuroendocrine markers. Based on the degree of immunoreactivity for these markers, tumours were classified as 0 (no expression of neuroendocrine markers), 1 (< 2% cells staining positive for neuroendocrine markers) and 2 (> 2% cells staining positive for neuroendocrine markers). Patients were followed up for more than 5 years or until death. RESULTS: Seven of 59 (11.8%) stage III cancers and 13/57 (22.8%) stage IV cancers belonged to group 2. The 96 patients of groups 0 and 1 lived for 48.9 months, whereas the 20 patients of group 2 survived for only 18.6 months (Kaplan-Meier survival curves, P < 0.001). The difference was most striking in stage III disease with 79.4 months' survival for combined groups 0 and 1, and 38.9 months' survival for group 2 (P < 0.01). Using the multivariate Cox regression model, the presence of more than 2% of cells with neuroendocrine differentiation was found to be an independent prognostic parameter for stage III and IV disease. No correlation was observed between neuroendocrine differentiation and tumour location, grade, depth of invasion or stage. CONCLUSION: Neuroendocrine differentiation is often seen in colorectal cancer. It is an independent prognostic factor in stage III-IV colorectal cancer.

Adenocarcinoma↗

PubMed2001

An Australian study on the sociocultural context of menopause: directions for contemporary nursing practice.

This research project by Berger (1997) investigates the physical, psychological, and sociocultural menopause experiences of a group of seventy women aged 45-70 years from Brisbane, Australia. Thus far the narrative provided for mid-life women shows a preoccupation with medical/biological perspectives that emphasize negative images of menopausal women as estrogen deficient and diseased. This new study is considered to be one of the few more recent attempts that investigates menopausal women within a sociocultural context and explores women's views about menopause as a normal, natural transition part of the ageing process. A qualitative approach (comprising focus groups and interviews) was aimed at women in mid-life who were willing to share their insights of this complex phase, to document individual variations and broad patterns. Findings provided enhanced understanding of many menopause aspects (such as appropriate treatment) that remain controversial. Content analysis uncovered three emerging themes: 1) contrary to popular beliefs menopause usually signified wellness; 2) apart from biological changes, the sociocultural context played a pivotal role in modifying menopause experiences; and 3) women did not feel adequately supported by health professionals. The findings signify that nurses are ideally placed to assist menopausal women in a variety of health care settings.

Aged↗

PubMed2000

Evaluation of calcium phosphates and experimental calcium phosphate bone cements using osteogenic cultures.

In this study, rat bone marrow cells (RBM) were used to evaluate two biodegradable calcium phosphate bone cements and bioactive calcium phosphate ceramics. The substances investigated were: two novel calcium phosphate cements, Biocement F and Biocement H, tricalcium phosphate (TCP), surface-modified alpha-tricalcium phosphate [TCP (s)] and a rapid resorbable calcium phosphate ceramic consisting of CaKPO(4) (sample code R5). RBM cells were cultured on disc-shaped test substrates for 14 days. The culture medium was changed daily and also examined for calcium, phosphate, and potassium concentrations. Specimens were evaluated using light microscopy, and morphometry of the cell-covered substrate surface, scanning electron microscopy, and energy dispersive X-ray analysis and morphometry of the cell-covered substrate surface. Areas of mineralization were identified by tetracyline labeling. Except for R 5, rat bone-marrow cells attached and grew on all substrate surfaces. Of the different calcium phosphate materials tested, TCP and TCP (s) facilitated osteoblast growth and extracellular matrix elaboration to the highest degree, followed by Biocements H and F. The inhibition of cell growth encountered with R 5 seems to be related to its high phosphate and potassium ion release.

Absorbable Implants↗

PubMed2000

Expression of SIALYL-Le(x) antigen defined by MAb AM-3 is an independent prognostic marker in colorectal carcinoma patients.

Expression of mucin-bound sialyl-Le(x) antigen during the progression of colorectal carcinoma and its potential prognostic value were analysed in sections of tumours from 182 patients with a documented follow-up by immunohistochemistry using the monoclonal antibody (MAb) AM-3. Two groups of colonic carcinomas with weak (n = 79) and strong (n = 103) sialyl-Le(x) expression were discerned. The percentage of strongly expressing tumours increased with the progression of the disease (UICC stage I = 10%, stage II = 46%, stage III = 63%, stage IV = 68%, p < 0.0001). Seventy-four percent of patients with carcinomas exhibiting a strong sialyl-Le(x) expression but only 34% of patients with weak sialyl-Le(x) expression died of the disease (p = 0.0026). In multivariate analysis, strong sialyl-Le(x) expression increased the relative risk of cancer-related death 3.8-fold (95% CI = 1.8-7.9, p = 0.00034). The separate analyses of patients in UICC stage II (n = 56), III (n =5 9) and IV (n = 57) revealed that strong sialyl-Le(x) expression was associated with a reduction of the 5-year overall survival rate in UICC stage II (84% vs. 54%, p = 0.0013) and in stage III patients (86% vs. 35%, p = 0.0008) after curative resection but was not relevant in patients with distant metastases. In conclusion, the strong expression of sialyl-Le(x) antigen defined by the MAb AM-3 in colorectal carcinomas is an independent unfavourable prognostic factor after curative resection in stage II and III patients. The predictive power of the sialyl-Le(x) expression may be helpful to define subgroups of patients at high risk for whom preventive adjuvant therapy can be selectively applied before the occurrence of detectable metastases.

Adult↗

PubMed2000

Natural T-cell response against MHC class I epitopes of epithelial cell adhesion molecule, her-2/neu, and carcinoembryonic antigen in patients with colorectal cancer.

The antigens epithelial cell adhesion molecule (Ep-CAM), her-2/neu, and carcinoembryonic antigen (CEA) are potential T-cell targets in antigen-specific vaccination-based cancer therapy. We performed this study to evaluate whether a natural specific T-cell response against these tumor-associated antigens (TAAs) already exists in patients with colorectal carcinoma (CRC). We used the IFN-gamma ELISPOT assay to detect circulating TAA-reactive T cells directly ex vivo in unstimulated peripheral blood mononuclear cells. We analyzed the T-cell response in peripheral blood mononuclear cells of 22 HLA-A2-positive patients with CRC and 8 HLA-A2-positive healthy subjects against 3 HLA A2-restricted peptide epitopes of the TAAs Ep-CAM (GLKAGVIAV), her-2/neu (IISAVVGIL), and CEA (YLSGANLNL). Seven of 22 patients but none of the 8 healthy subjects had T cells specifically secreting IFN-gamma in response to one to three of these antigens (n = 4, Ep-CAM; n = 5, her-2/neu; n = 6, CEA). In three of the seven responding patients, TAA-reactive T cells were further characterized by flow cytometry. In all three patients, the majority of these T cells have a CD3+CD8+IFN-gamma+CD69+CD45RA+ phenotype, resembling activated effector-type T cells. T-cell responses occurred only in patients with metastatic disease (Dukes' stages C and D). The results of this study indicate that natural T-cell responses against TAAs occur in approximately one-half of CRC patients with involvement of lymph nodes or distant metastases, but not in CRC patients with disease confined to the intestinum.

Antibodies, Monoclonal↗

PubMed2000

Anatomical basis of sleep-related breathing abnormalities in children with nasal obstruction.

OBJECTIVE: To define, in a group of children with nasal obstruction, the anatomical differences that differentiate those with quiet, unobstructed nocturnal respiration from those with obstructive sleep-related breathing abnormalities (snoring and obstructive sleep apnea). DESIGN: Case series. PATIENTS: Fifty-nine children aged 3 to 13 years (35 boys and 24 girls) with nasal obstruction and without tonsillar hypertrophy, known craniofacial syndromes, or neuromuscular diseases were included in the study. MAIN OUTCOME MEASURES: Each patient was categorized as to severity of nocturnal obstructive breathing symptoms. Angular and linear cephalometric measurements were used for assessment of craniofacial features. Clinical symptom scores were correlated with the cephalometric measurements. RESULTS: Significant craniofacial abnormalities were identified in patients prone to obstructive breathing patterns: increased flexure of the cranial base and bony nasopharynx, opening of the gonial angle, shortened mandibular length, dorsocaudal location of the hyoid, reduced posterior airway space, and increased velar thickness. CONCLUSIONS: A number of anatomical abnormalities may contribute to sleep-related abnormal breathing in otherwise normal children with nasal obstruction. Our results suggest that symptomatic children show some of the same skeletal and soft-tissue configurations that are found in adults with obstructive sleep apnea. While adenoidectomy is generally an effective treatment in children with obstructive sleep-related breathing abnormalities, the underlying craniofacial variances that remain after adenoidectomy may predispose these patients to redevelopment of obstructive breathing abnormalities in adulthood.

Adolescent↗

PubMed2000

Increased carboplatin concentration in liver tumors through temporary flow retardation with starch microspheres (Spherex) and gelatin powder (Gelfoam): an experimental study in liver tumor-bearing rabbits.

Regional chemotherapy of primary and secondary malignant liver tumors is superior to systemic therapy. The regional advantage can be further increased by flow retardation. Absorbable gelatin powder (Gelfoam) and starch microspheres (Spherex) may serve as embolizing agents because of their particle size and embolization time. Carboplatin was for the first time applied as a cytostatic agent in regional chemotherapy. Embolization and flow retardation times were measured. The embolization time of Gelfoam was 27 min, and that of starch microspheres (Spherex), 7 min, on average. Mean flow retardation of Gelfoam was 153 min, and that of starch microspheres (Spherex) 38 min. The concentration differences in systemic and regional chemotherapy were determined in VX-2 liver tumor-bearing rabbits. In regional chemotherapy, the tumor concentration was increased by a factor of 3.6 compared with systemic therapy. Coapplication with an embolizing agent increased the tumor concentration of carboplatin by a factor of 44 to 47. Concentrations of absorbable gelatin powder (Gelfoam) and starch microspheres (Spherex) did not differ significantly.

Animals↗

PubMed2000

Quantitative ultrasound imaging of the calcaneus: precision and variations during a 120-Day bed rest.

This study reports on the precision and variation of quantitative ultrasound (US) parameters [broadband ultrasonic attenuation (BUA) or slope of the frequency-dependent attenuation in dB/MHz and speed of sound (SOS m/second)] after 120 days of continuous bed rest in six normal male volunteers. Quantitative US was measured at the calcaneus using a new US bone imaging scanner. The measurements were carried out on both heels at approximately 2-week intervals. The short-term precision was 0.31% for SOS and 2.8% for BUA. The long-term precision was 0.58% for SOS, 4.7% for BUA. A significant decrease of SOS values of -26 m/second (P < 0.0001) for the right heel and -17 m/second (P < 0.05) for the left heel was found at the group level. In terms of percentage change this represents -1.7% for the right heel and -1.1% for the left heel. These percentage decrements were 3.5-5.5 times that of the short-term precision and 2-3 times that of the long-term precision of the technique. At the individual level, the decrease of SOS was statistically significant (P < 0.05) or marginally significant (P < 0.1) for four out of 6 subjects. For 2 other subjects, similar trends were observed, but without reaching statistical significance. BUA did not change significantly during follow-up. These results are consistent with previous findings on changes of ultrasonic properties from the calcaneus during aging, pregnancy, or therapy, showing that calcaneus SOS is a valuable index of bone loss. These preliminary data suggest that prolonged exposure to simulated weightlessness may lead to a lower SOS, which then could be used for the follow-up of bone demineralization occurring during long-term space flights.

Adult↗

PubMed2000

High-frequency ultrasound characterization of microporous biointegrable polymers in cornea using acoustic parameters.

The current work deals with the use of high-frequency quantitative backscatter acoustic microscopy for the evaluation of the biointegration of microporous polymer implants used as support of artificial cornea. A three-dimensional (3-D) 80 MHz ultrasound microscope (25 microns axial resolution at focus) was used for the imaging and characterization of the progressive biointegration of polymers implanted in rabbit cornea. In-vitro and in-vivo studies were performed. Quantitative assessment of the structural changes in the biomaterial was performed using the spectral analysis of the radio frequency signal and the estimation of acoustic parameters in the 10-65 MHz frequency bandwidth. Correlation of in-vitro ultrasound data with histologic findings has shown that attenuation and backscatter coefficients are sensitive to the changes in the polymer pore content with time. Our results obtained in vivo demonstrated that 3-D 80 MHz echography coupled with quantitative characterization provide a unique tool for the non-invasive and objective follow-up of the implant biointegration and should contribute to clinical management of artificial cornea.

Acoustics↗