Effects of processing on structural, mechanical and biological properties of collagen-based substrates for regenerative medicine

The aim of this work was to investigate the structural features of type I collagen isoforms and collagen-based films at atomic and molecular scales, in order to evaluate whether and to what extent different protocols of slurry synthesis may change the protein structure and the final properties of the developed scaffolds. Wide Angle X-ray Scattering data on raw materials demonstrated the preferential orientation of collagen molecules in equine tendon-derived collagens, while randomly oriented molecules were found in bovine skin collagens, together with a lower crystalline degree, analyzed by the assessment of FWHM (Full Width at Half Maximum), and a certain degree of salt contamination. WAXS and FT-IR (Fourier Transform Infrared) analyses on bovine collagen-based films, showed that mechanical homogenization of slurry in acidic solution was the treatment ensuring a high content of super-organization of collagen into triple helices and a high crystalline domain into the material. In vitro tests on rat Schwannoma cells showed that Schwann cell differentiation into myelinating cells was dependent on the specific collagen film being used, and was found to be stimulated in case of homogenization-treated samples. Finally DHT/EDC crosslinking treatment was shown to affect mechanical stiffness of films depending on collagen source and processing conditions.

Interfibrillar packing of bovine cornea by table-top and synchrotron scanning SAXS microscopy

Bovine cornea was studied with scanning small-angle X-ray scattering (SAXS) microscopy, by using both synchrotron radiation and a microfocus laboratory source. A combination of statistical (adaptive binning and canonical correlation analysis) and crystallographic (pair distribution function analysis) approaches allowed inspection of the collagen lateral packing of the supramolecular structure. Results reveal (i) a decrease of the interfibrillar distance and of the shell thickness around the fibrils from the periphery to the center of the cornea, (ii) a uniform fibril diameter across the explored area, and (iii) a distorted quasi-hexagonal arrangement of the collagen fibrils. The results are in agreement with existing literature. The overlap between laboratory and synchrotron-radiation data opens new perspectives for further studies on collagen-based/engineered tissues by the SAXS microscopy technique at laboratory-scale facilities.

An optimized table-top small-angle X-ray scattering set-up for the nanoscale structural analysis of soft matter

The paper shows how a table top superbright microfocus laboratory X-ray source and an innovative restoring-data algorithm, used in combination, allow to analyze the super molecular structure of soft matter by means of Small Angle X-ray Scattering ex-situ experiments. The proposed theoretical approach is aimed to restore diffraction features from SAXS profiles collected from low scattering biomaterials or soft tissues, and therefore to deal with extremely noisy diffraction SAXS profiles/maps. As biological test cases we inspected: i) residues of exosomes' drops from healthy epithelial colon cell line and colorectal cancer cells; ii) collagen/human elastin artificial scaffolds developed for vascular tissue engineering applications; iii) apoferritin protein in solution. Our results show how this combination can provide morphological/structural nanoscale information to characterize new artificial biomaterials and/or to get insight into the transition between healthy and pathological tissues during the progression of a disease, or to morphologically characterize nanoscale proteins, based on SAXS data collected in a room-sized laboratory.

Three-dimensional coherent diffractive imaging on non-periodic specimens at the ESRF beamline ID10

The progress of tomographic coherent diffractive imaging with hard X-rays at the ID10 beamline of the European Synchrotron Radiation Facility is presented. The performance of the instrument is demonstrated by imaging a cluster of Fe2P magnetic nanorods at 59 nm 3D resolution by phasing a diffraction volume measured at 8 keV photon energy. The result obtained shows progress in three-dimensional imaging of non-crystalline samples in air with hard X-rays.

Scanning SAXS–WAXS microscopy on osteoarthritis-affected bone – an age-related study

Osteoarthritis (OA), among other bone pathologies, is expected to determine supramolecular changes at the level of the mineralized collagen fiber. In a proof-of-principle study, bone biopsies were collected from six coxarthritis-affected patients, aged 62–87 years, during hip prosthesis implant surgery, sliced down to 100 µm-thick tissues, and investigated using scanning small-angle and wide-angle X-ray scattering (SAXS and WAXS) transmission microscopy. A multi-modal imaging evaluation of the SAXS and WAXS data, combined with principal component and canonical correlation analyses, allowed the transformation of the raw data into microscopy images and inspection of the nanoscale structure of the mineralized collagen fibers across mm2tissue areas. The combined scanning SAXS and WAXS microscopy is shown to be a suitable choice for characterizing and quantifying the nanostructural properties of collagen over extended areas. The results suggest the existence of a correlation between age and cross-linking-induced rigidity of collagen fibers.

X-ray microimaging laboratory (XMI-LAB)

A first-generation-synchrotron-class X-ray laboratory microsource, coupled to a three-pinhole camera, is presented. It allows (i) small- and wide-angle X-ray scattering images to be acquired simultaneously, and (ii) scanning small- and wide-angle X-ray scattering microscopy to be carried out. As representative applications, the structural complexity of a biological natural material (human bone biopsy) and of a metamaterial (colloidal nanocrystal assembly) are inspected at different length scales, studying the atomic/molecular ordering by (grazing-incidence) wide-angle X-ray scattering and the morphological/structural conformation by (grazing-incidence) small-angle X-ray scattering. In particular, the grazing-incidence measurement geometries are needed for inspecting materials lying on top of surfaces or buried underneath surfaces.

Phasing diffuse scattering. Application of the SIR2002 algorithm to the non-crystallographic phase problem

A new phasing algorithm has been used to determine the phases of diffuse elastic X-ray scattering from a non-periodic array of gold balls of 50 nm diameter. Two-dimensional real-space images, showing the charge-density distribution of the balls, have been reconstructed at 50 nm resolution from transmission diffraction patterns recorded at 550 eV energy. The reconstructed image fits well with a scanning-electron-microscope (SEM) image of the same sample. The algorithm, which uses only the density modification portion of the SIR2002 program, is compared with the results obtained via the Gerchberg-Saxton-Fienup HiO algorithm. The new algorithm requires no knowledge of the object's boundary and proceeds from low to high resolution. In this way, the relationship between density modification in crystallography and the HiO algorithm used in signal and image processing is elucidated.

Strain Determination in Epitaxic Films of Materials of Orthorhombic Symmetry by High-Resolution X-ray Diffraction

In this paper, we derive the most general expression of the X-ray incidence parameter. The new expression of the incidence parameter allows us to determine the lattice deformation of strained epitaxic films of materials of orthorhombic symmetry by high-resolution X-ray diffraction. The strain status of epilayers can be evaluated by using layer and substrate peaks of different reflections. In particular, the lattice mismatch (strain fields) between substrate and epilayers can be determined even if the heterostructure is made of materials of different crystallographic symmetry,e.g.high-Tcperov-skite superconductor thin films deposited on SrTiO3. In addition, the new expression of the incidence parameter takes into account the most general uniform lattice deformation of the epilayer crystal unit cell. Furthermore, it should be noted that the new expression is particularly useful if the angular separation Δθ between layer and substrate Bragg peaks is so large that the more conventional first- or second-order approximations in Δθ of the incidence parameter are not valid.

Long-term follow-up of patients enrolled in a randomized trial comparing perioperative chemotherapy and surgery with surgery alone in resectable stage IIIA non-small-cell lung cancer

Our previously reported randomized study of patients with untreated, potentially resectable clinical stage IIIA non-small-cell lung cancer found that patients treated with perioperative chemotherapy and surgery had a significant increase in median survival compared to patients treated with surgery alone. We have now re-analyzed the results of the study with a median time from random allocation to analysis for all patients of 82 months. The increase in survival conferred by perioperative chemotherapy was maintained during the period of extended observation.

[Renal agenesis associated with homolateral ovarian dysplasia. A case report]

The Authors describe a case of renal agenesis with ipsilateral ovarian dysplasia. The clinical features are abdominal mass and pain and then the treatment is laparoscopic ablation.

A randomized trial comparing perioperative chemotherapy and surgery with surgery alone in resectable stage IIIA non-small-cell lung cancer

BACKGROUND

Patients with resectable stage IIIA non-small-cell lung cancer have a low survival rate following standard surgical treatment. Nonrandomized trials in which induction chemotherapy or a combination of chemotherapy and radiation prior to surgery were used to treat patients with regionally advanced primary cancers have suggested that survival is improved when compared with treatment by surgery alone.

PURPOSE

We performed a prospective, randomized study of patients with previously untreated, potentially resectable clinical stage IIIA non-small-cell lung cancer to compare the results of perioperative chemotherapy and surgery with those of surgery alone.

METHODS

This trial was designed to test the null hypothesis that the proportion of patients surviving 3 years is 12% for either treatment group against the alternate hypothesis that the 3-year survival rate would be 12% in the surgery alone group and 32% in the perioperative chemotherapy group. The estimated required sample size was 65 patients in each group. The trial was terminated at an early time according to the method of O'Brien and Fleming following a single unplanned interim analysis. The decision to terminate the trial was based on ethical considerations, the magnitude of the treatment effect, and the high degree of statistical significance attained. In total, 60 patients were randomly assigned between 1987 and 1993 to receive either six cycles of perioperative chemotherapy (cyclophosphamide, etoposide, and cisplatin) and surgery (28 patients) or surgery alone (32 patients). For patients in the former group, tumor measurements were made before each course of chemotherapy and the clinical tumor response was evaluated after three cycles of chemotherapy; they then underwent surgical resection. Patients who had documented tumor regression after preoperative chemotherapy received three additional cycles of chemotherapy after surgery.

RESULTS

After three cycles of preoperative chemotherapy, the rate of clinical major response was 35%. Patients treated with perioperative chemotherapy and surgery had an estimated median survival of 64 months compared with 11 months for patients who had surgery alone (P < .008 by log-rank test; P < .018 by Wilcoxon test). The estimated 2- and 3-year survival rates were 60% and 56% for the perioperative chemotherapy patients and 25% and 15% for those who had surgery alone, respectively.

CONCLUSIONS

In this trial, the treatment strategy using perioperative chemotherapy and surgery was more effective than surgery alone.

IMPLICATIONS

This clinical trial strengthens the validity of using perioperative chemotherapy in the management of patients with resectable stage IIIA non-small-cell lung cancer. Further investigation of the perioperative chemotherapy strategy in earlier stage lung cancer is warranted.

[Correlation between availability of GM progenitors and endogenous CSA production in neutropenia]

We studied some cases with granulopoiesis disorders, owing to different causes, all showing peripheral neutropenia. Can these cases benefit by the growth factors G-CSF administration? To answer this question we assayed the bone marrow CFU-GM growth of the neutropenic patients with standard source of CSA and employing as CSA source the autologous peripheral blood mononucleated cells (APBMN). We proposed ourselves to investigate the granulopoiesis regulation referring to the relation between number of GM-progenitor cells and levels of CSA. The bone marrow CFU-GM cultures were performed by Pike and Robinson's double layer agar technique. For the evaluation of growth we applied the criterion of the dishes topographic lecture according to Ghizzi and De Caro. We plotted the experimental data both as absolute count of observed aggregates (tPP) and as dynamic patterns of in vitro aggregate proliferation, by differentiating the early proliferative events (AC-A and AC-B) from the later ones (AC-C). We observed cases showing growths higher under CSA standard source than under autologous source (CAA) and vice versa. In other cases there are not noteworthy differences. To estimate these growth patterns and to interpret the experimental data we correlated the autologous stimulus capacity to the CFU-GM absolute counts. Most cases of neutropenia showed inverse correlation between the two indexes. We consider a reduced stimulus capacity may be fit when the CFU-GM growth is high. We retain this capacity of modulating the CSA production as index of kept regulation of the granulopoiesis and, then, these cases can spontaneously evolve towards the neutropenia resolution.

[In vitro sensitivity of accessory hematopoietic cells from neutropenic subjects to the activity of human gamma-globulin]

We studied eight patients all showing neutropenia: drug-induced isolated neutropenic failure (2 cases), immune cell-mediated neutropenia (2 case), severe bone marrow hypoplasia (2 cases), dysmyelopoietic syndrome (1 case), cyclic neutropenia (1 case). Aim of the study was to assay the effect on CSA production of the pretreatment of autologous peripheral blood mononucleated cells (APBMN) with immunoglobulins (Ig). The CFU-GM growth were tested in different experimental conditions: with standard source of CSA, with autologous source, with autologous source modified by means of the preincubation of the autologous cells with Ig. The bone marrow CFU-GM culture was performed by Pike and Robinson's double layer agar technique. The experimental data were pointed out with topographic lecture of the dishes repeated at two times so as to obtain besides the aggregates global growth their dynamic classes too. We observed that the APBMN cells pretreatment with Ig modulates CSA production: represses it in cases showing high production and increases it in those showing low production. The effect of Ig modulation appears clearer on the GM-progenitor proliferating late (AC-C) than on those proliferating early (AC-A). This effect turned out to be particularly evident in a case with immune cell-mediated neutropenia and in both cases with drug-neutropenia. We retain that the monomers Ig could block Fc receptors and modulate their expression on macrophagic cells, conditioning in this way the CSA production. The parenteral administration of intact Ig (in vivo treatment of the APBMN cells) appears therefore helpful both in cases with CSA defect and in cases with excess of CSA production.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of bisphosphonate on the in vitro proliferation dynamics of CFU-GM]

Bisphosphonates, potent inhibitors of osteoclast-mediated bone resorption, affect different ways of the intracellular metabolism of the osteoclasts. Likewise other cell lines are affected by bisphosphonate action, among these the macrophagic cells. So we assayed the dichloromethylene diphosphonate (clodronate, Cl2MBP) effect on the in vitro proliferation of granulocytic-macrophage progenitor cells (GM-progenitors). The bone marrow progenitor cells of four healthy volunteers were plated in double layer agar by Pike and Robinson's technique, with the addition of clodronate concentrations rising from 0.004 till 4.0 mMol. For each experimental point we evaluated: 1) the global growth of the proliferating GM-progenitors (tPP) deduced from the number of the counted cellular aggregates (CA); 2) the mean size (m.s.) of the CA; 3) the total proliferative capacity (TPC), deduced from the aggregate mean size per the number of the CA; 4) the contribution to the proliferative events by each subsets of proliferating GM-progenitors (early proliferating GM-progenitors, forming the CA present at the 7th day of the in vitro culture; later proliferating GM-progenitors, appearing only at the 12th day). The dose-effect curve showed decrease both of the tPP and TPC for increasing concentrations of clodronate up to a complete growth inhibition at the concentration 4.23 mMol of clodronate. Concerning the m.s. of the in culture growth aggregates, in three of the four cases it appears unvaried up to the Cl2MBP concentration 0.4 mMol. The trends of dose-effect curves have been analysed both for colonies (CA-P4) and for clusters (CA-P1, -P2, -P3 of our classification).(ABSTRACT TRUNCATED AT 250 WORDS)

Kinetics and pharmacodynamic effects of a novel prodrug of N-methyldopamine at single dose in healthy volunteers

Kinetics and cardiovascular effects of SIM2055 (CAS 103878-96-2), the 4-O-phosphate of N-methyldopamine (epinine), at single dose by the oral route were studied in 9 healthy adult volunteers (6 women and 3 men) ranging in age from 22 to 39 years. SIM2055 was administered at increasing doses (from 100 to 300 mg). Plasma concentrations of free epinine were not detectable after the 100 mg dose, but were measurable after the 200 mg and 300 mg doses. Pharmacokinetic data suggest that in man SIM2055 is promptly absorbed, quickly hydrolysed to epinine, metabolized to homovanillic acid and 3,4-dihydroxy-phenylacetic acid, conjugated with sulphuric acid and excreted in large amounts into urine. The 24-h urinary recovery of the 3 metabolites considered together, expressed as a percentage of the dose of SIM2055 administered, was 78 +/- 6 with the 100 mg dose, 66 +/- 11 with the 200 mg dose and 55 +/- 6 with the 300 mg dose (mean +/- S. D.). SIM2055 was well tolerated by all subjects. After its administration, the heart rate and the systolic and diastolic blood pressure presented no systemic or clinically significant variations. No substantial changes were observed with the ECG parameters. No subject reported gastric or systemic effects during the period of observation.

[Activity of natural fatty acids on erythrocyte osmotic resistance]

The aim of the present study was to assess the influence on the functional characteristics of the erythrocyte membrane of adding in vitro different natural fatty acids to blood taken from normal subjects. Blood samples were collected without stasis from healthy volunteers, anticoagulated with heparin or EDTA and incubated at 37 degrees C for 60 min with the different fatty acids at concentrations ranging between 1 x 10(-4) and 3 x 10(-2) molar. Two ml of blood were used for each test. The treated blood was added to graded solutions of NaCl (0.90-0.20 g/dl) at a ratio of 100 microliters/5 ml of solution. The suspensions were kept at room temperature and centrifuged for 10 min at 2000 g, in order to accelerate the sedimentation of the erythrocytes which had not been broken down and so as to obtain a clear supernatant for spectrophotometry of the dissolved haemoglobin. Readings were compared with those obtained from blood samples which had been completely haemolyzed by suspension in distilled water. Results obtained with the blood samples prepared with the fatty acids were compared with control samples from the same donor, also incubated at 37 degrees C for 60 min. Preincubation of the erythrocyte with butyric or caproic or oleic acid at concentrations ranging between 5 and 20 millimolar, provoked a clear deterioration of the osmotic resistances of the erythrocytes, in proportion to the concentration of the fatty acid used. The osmotic insult was systematically more effective in those samples anticoagulated with EDTA than those treated with heparin.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth of bone marrow CFU-GM in a case of cyclical neutropenia. Preliminary report

We studied bone marrow CFU-GM growth behaviour of a 9-year-old male child with cyclic neutropenia. The cultures were performed on day 0 and on day 13 of cyclic oscillation, in order to study some correspondences between CFU-GM culture parameters and the phases of a whole cyclic oscillation "in vivo". We explored the CFU-GM growth under three different conditions of GM-CSA production: a) standard source of CSA; b) endogenous GM-CSA assay; c) GM-CSA-gamma-globulin assay. At both observation times the endogenous GM-CSA assay produced more aggregates than the baseline culture. The GM-CSA-gamma-globulin assay partly corrected the growth increase, produced by endogenous assay. At time 0, at the nadir of peripheral blood neutrophils, there was a balance between the number of aggregates, appeared early in culture and early degenerated, and those appeared late. From progenitor cells culture performed on day 13 of cycle, a week before the zenith of neutrophils in vivo, we obtained an increase in aggregates, which appeared late. The values of CFU-GM grown from the culture performed on day 13 reached higher levels than the ones performed on day 0. The CFU-GM growth behaviour shows that in our case with cyclic neutropenia there is no defect in progenitor cells, while on the contrary there is an increase in CSA production.

[Effect of testosterone on in vitro proliferation of bone marrow granulocyte-macrophage progenitor cells (CFU-GM). I. Observations in normal subjects]

A hypothetical mechanism whereby testosterone propionate (Tp) seems to stimulate the granulopoiesis has been studied. We cultured in agar human bone marrow cells harvested 24 h before and after parenteral administration of 100 mg Tp to 4 volunteer subjects having no hematologic disorders. The dynamic features of the proliferating progenitor cells (growth of the CFU-GM) were studied in agar cultures according to an original method of repeated topographic scoring of dishes. In this way we obtained a classification of the newformed cellular aggregates (CA) based on their size and on their appearance time in vitro. The results were analysed according to the following dynamic classification of the CFU-GM: AC-A = CA observed on day 7 of culture and degenerate on day 12; AC-B = CA present on both days 7 and 12, distinct as B-persistent (CA persistent with the same size in the interval between 7th and 12th day of incubation) and as B-progressed (CA progressed to a wider size in the same interval); AC-C = CA appeared ex novo at the 12th day of culture. After acute Tp pre-treatment we observed, in the first period of culture (observations made on day 7), a decrease of the number of the small size CA (P1 = 5-10 cells), while the number of the wide size CA (P2 = 11-30 cells; P3 = 31-50 cells; P4 = more than 50 cells per CA) was increased. The number of the AC-A was unmodified.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics and bioavailability of oral acetylcysteine in healthy volunteers

The plasma pharmacokinetics of oral acetylcysteine(N-acetylcysteine, NAC) after the administration of single 600 mg and repeated 200 mg doses and the relative bioavailability of the two regimens were studied in 12 adult subjects. On two different occasions in a cross-over, balanced fashion the subjects were administered orally either a single dose of NAC 600 mg as effervescent tablets or 4 repeated doses of NAC as granules in sachets at the regimen of 200 mg t.i.d. Venous blood samples were obtained just before dosing and 20, 40 min, 1, 1.5, 2, 3, 4, 6, 8, 10 and 12 h after the administration of NAC 600 mg; with the 1st, the 2nd and the 4th doses of NAC 200 mg samples were taken just before dosing and after 20, 40 min, 1, 1.5, 2, 3, 4, 6 and 8 h, the last sampling after the 1st dose being the one before the 2nd dose. A detailed description of the assaying methods of NAC is given in the text. As indexes of bioavailability Cmax' tmax and AUC of NAC plasma concentrations were considered and MRT was taken as an estimate of its persistence in plasma. NAC was quickly absorbed without any significant difference in tmax among the doses. With the 600 mg dose Cmax' AUC and MRT were greater than with a single 200 mg dose; after summing up the values of these parameters for the 200 mg doses no significant differences were observed in comparison to the single 600 mg dose in Cmax and AUC, while MRT resulted significantly higher.(ABSTRACT TRUNCATED AT 250 WORDS)

[Carcinoid of Meckel's diverticulum (a case associated with adenocarcinoma of the rectum)]

The authors present a clinical case characterized by a rare combination of diseases: Meckel's diverticulum carcinoid and intestinal neoplasm. The clinical aspects and related implications are dealth with at some length, showing the relationship between these and tumour size as well as their importance in the therapeutic management and prognostic evaluation of the carcinoid tumour.

[Biochemical diagnosis of insulinoma: correlations between blood glucose, blood insulin and the titer of plasma non-esterified fatty acids during fasting and during various diagnostic tests]

The difficulty of clinical and biochemical diagnosis of insulinoma lies in the extreme variability of both clinical symptoms and glycaemia/insulinaemia levels, so that neither parameter is a totally reliable diagnostic indicator. The possibility of introducing a third parameter, the non-esterified fatty acid (FFA) level, to enhance the reliability of insulinoma diagnosis was therefore investigated. The behaviour of glucose, insulin and plasmatic FFA levels and the correlation of the three parameters were studied in 4 patients whose suspected insulinomas were later surgically confirmed. The tests applied were as follows: 24 hour fast followed by endovenous glucose, oral glucose administration, tolbutamide stimulus test, adrenaline and glucagon tests. The results revealed anomalies in insulinaemia and glycaemia behaviour such as have already, in part, been described in organic hyperinsulinism, e.g. the discrepancy between insulin and glucose levels after prolonged fasting. It was also clear that the parameters examined still leave much room for uncertainly in the biochemical diagnosis of insulinomas. Numerous anomalies were also observed in the behaviour of plasmatic FFA. For example lipid mobilisation was often reduced in conditions that normally stimulate it (fasting, the administration of catecholamines). Equally the prolonged blockage of lipid mobilisation was encountered in the presence of factors that normally reduce lipolysis (endovenous glucose). On the basis of these results it is suggested that a combined assessment of glucose and plasmatic FFA levels may be a more sensitive diagnostic indicator of insulinoma than the insulin/glucose ratio commonly reported in the literature. The mechanism behind the lipid mobilisation anomalies of insulinomas is also discussed in the light of its apparent connection with the glucose/insulin interaction characteristic of the condition.

Quantitative DNA. Comparative studies of a cellular marker for bronchogenic carcinoma

During the course of induction of bronchogenic carcinoma in a colony of standard-bred beagles, serial cytologic and biopsy material was obtained under direct bronchoscopy. Cytological changes followed the sequence from metaplasia to carcinoma, closely simulating those features observed in humans, but with subtle differences characterized as species variations. Quantitative DNA done by image analysis correlated directly with the severity of cytologic atypia and also corresponded well with data obtained from humans. Equivalent studies in human bronchogenic carcinoma have shown similar results and strongly suggest that graded hyperploidy accurately reflects atypia in the lung and qualifies as an interspecies tumor marker.