Crossed-beam and theoretical studies of multichannel nonadiabatic reactions: branching fractions and role of intersystem crossing for O(3P) + 1,3-butadiene.

Atomic oxygen reactions can contribute significantly to the oxidation of unsaturated aliphatic and aromatic hydrocarbons. The reaction mechanism is started by electrophilic O atom addition to the unsaturated bond(s) to form "chemically activated" triplet oxy-intermediate(s), which can evolve adiabatically on the triplet potential energy surface (PES) and nonadiabatically via intersystem crossing on the singlet PES, forming intermediates that undergo unimolecular decomposition to a variety of bimolecular product channels. Here, we apply a combined crossed molecular beam (CMB)-theoretical approach to the study of the O(3P) + 1,3-butadiene reaction. Although the kinetics of this reaction have been extensively investigated, little is known about the primary products and their branching fractions (BFs). In the present work, a total of eight product channels were observed and characterized in a CMB experiment at a collision energy of 32.6 kJ mol-1. Synergic ab initio transition-state theory-based master equation simulations coupled with nonadiabatic transition-state theory on coupled triplet/singlet PESs were employed to compute the product BFs and assist the interpretation of the CMB experimental results. The good agreement found between the theoretical predictions and CMB experiments supported the use of the adopted methodology for the prediction of channel-specific rate constants as a function of temperature and pressure suitable to be used for the kinetic modeling of 1,3-butadiene oxidation and of systems where 1,3-butadiene is an important intermediate.

EStokTP: Electronic Structure to Temperature- and Pressure-Dependent Rate Constants-A Code for Automatically Predicting the Thermal Kinetics of Reactions.

A priori rate predictions for gas phase reactions have undergone a gradual but dramatic transformation, with current predictions often rivaling the accuracy of the best available experimental data. The utility of such kinetic predictions would be greatly magnified if they could more readily be implemented for large numbers of systems. Here, we report the development of a new computational environment, namely, EStokTP, that reduces the human effort involved in the rate prediction for single channel reactions essentially to the specification of the methodology to be employed. The code can also be used to obtain all the necessary master equation building blocks for more complex reactions. In general, the prediction of rate constants involves two steps, with the first consisting of a set of electronic structure calculations and the second in the application of some form of kinetic solver, such as a transition state theory (TST)-based master equation solver. EStokTP provides a fully integrated treatment of both steps through calls to external codes to perform first the electronic structure and then the master equation calculations. It focuses on generating, extracting, and organizing the necessary structural properties from a sequence of calls to electronic structure codes, with robust automatic failure recovery options to limit human intervention. The code implements one or multidimensional hindered rotor treatments of internal torsional modes (with automated projection from the Hessian and with optional vibrationally adiabatic corrections), Eckart and multidimensional tunneling models (such as small curvature theory), and variational treatments (based on intrinsic reaction coordinate following). This focus on a robust implementation of high-level TST methods allows the code to be used in high accuracy studies of large sets of reactions, as illustrated here through sample studies of a few hundred reactions. At present, the following reaction types are implemented in EStokTP: abstraction, addition, isomerization, and beta-decomposition. Preliminary protocols for treating barrierless reactions and multiple-well and/or multiple-channel potential energy surfaces are also illustrated.

H-Abstraction reactions by OH, HO2, O, O2 and benzyl radical addition to O2 and their implications for kinetic modelling of toluene oxidation.

Alkylated aromatics constitute a significant fraction of the components commonly found in commercial fuels. Toluene is typically considered as a reference fuel. Together with n-heptane and iso-octane, it allows for realistic emulations of the behavior of real fuels by the means of surrogate mixture formulations. Moreover, it is a key precursor for the formation of poly-aromatic hydrocarbons, which are of relevance to understanding soot growth and oxidation mechanisms. In this study the POLIMI kinetic model is first updated based on the literature and on recent kinetic modelling studies of toluene pyrolysis and oxidation. Then, important reaction pathways are investigated by means of high-level theoretical methods, thereby advancing the present knowledge on toluene oxidation. H-Abstraction reactions by OH, HO2, O and O2, and the reactivity on the multi well benzyl-oxygen (C6H5CH2 + O2) potential energy surface (PES) were investigated using electronic structure calculations, transition state theory in its conventional, variational, and variable reaction coordinate forms (VRC-TST), and master equation calculations. Exploration of the effect on POLIMI model performance of literature rate constants and of the present calculations provides valuable guidelines for implementation of the new rate parameters in existing toluene kinetic models.

Efficacy of an emollient dermoprotective cream in the treatment of elderly skin affected by xerosis.

AIM: Xerosis cutis is a frequent condition in the elderly and the topical treatments are aimed to maintain a balance between the physiological components of the epidermis and an optimal moisturization. The aim was to evaluate the efficacy of a dermoprotective cream, glycerol and paraffin-based, in the treatment of individuals affected by senile xerosis. METHODS: The patients were recruited at the Professional Dermatology and Allergology Outpatient Clinic of the San Gallicano Dermatological Institute of Rome, between 1st January 2013 and 30th September 2014. To assess the efficacy of the cream, two different areas of treatment were identified in each patient upper the limbs. All patients were staged at baseline (T0) and evaluated after 14 days (T1) and 28 days (T2) of topical treatment, using five clinical parameters: scaling, sensation of skin tightness, presence of fissuring and excoriations from scratching and erythema. The itching degree was also evaluated using a 10-steps analogical scale. RESULTS: Fifty patients with xerosis, 25 with a severe and 25 with a moderate form, over 60 were recruited and evaluated. Median age was 65 years (IQR=61-70). After 28 day of topical administration of the cream, the 54.0% of patients showed the absence of signs of xerosis, the 44.0% a mild form and the 2.0% (one patient) a moderate form. Consistently, a progressive and significative reduction of itching and transepidermal water loss (TEWL), and an improvement in skin hydration was also measured. A good profile of tolerability and no episodes of undesirable side effects, was also observed. CONCLUSION: The topical daily use of a cream glycerol and paraffin-based, seem to able to control the xerosis in elderly patients, with a significant reduction of all associated signs and symptoms. Further additional data should be collected to better confirm the role of the topical treatment in the control of disease.

Immunologic biomarkers for clinical and therapeutic management of psoriasis.

BACKGROUND: The therapeutic management of psoriasis includes conventional treatments as well as the new generation of highly effective TNF-α inhibitors. However, psoriasis has proven to be a complex therapeutic challenge and treatment failures are not uncommon. Thus, laboratory biomarkers of disease progression/therapeutic efficacy may greatly help in the clinical management of psoriasis. AIMS: To identify laboratory biomarkers for clinical management and therapeutic monitoring of psoriasis. METHODS: An observational study performed on 59 patients, presenting moderate to severe psoriasis, undergoing treatment with anti-TNF-α agents (etanercept, adalimumab, and infliximab). Soluble and cellular immune/inflammatory parameters were assessed at baseline and after 12 and 24 weeks of treatment. RESULTS: Clinical efficacy was achieved in 88% of the subjects at 12 weeks, reaching 90% after 24 weeks. IL-6 and IL-22, which were elevated at baseline, were significantly reduced, in association with a significant decrease of CLA+ T cells and an increase of Treg lymphocytes. T, B, and NK cell subsets and T cell response to recall antigens did not show any evidence of immune suppression. CONCLUSIONS: Immune/inflammatory parameters including IL-6 and IL-22, CLA+ T cells, and Treg lymphocytes may prove to be valuable laboratory tools for the clinical and therapeutic monitoring of psoriasis.

Ultrastructural age-related changes in the sensory corpuscles of the human genital skin.

In human genital skin the majority of superficial sensory corpuscles is represented by glomerular corpuscles. These corpuscles show an own morphology. Our aim is to compare the ultra-structure of superficial sensory corpuscles in the penis skin of younger and older subjects. In this report the ultra-structure of the sensitive corpuscle in the penis skin of the younger and older subjects was compared, showing that the genital skin of the older humans contains more simple complexes than the younger ones. Our findings support the view that the age-related changes that can be observed in human glomerular genital corpuscles are consistent with an increase of the simple complexes and a strong decrease of the poly-lamellar one in the older people. These findings demonstrate that human genital corpuscles underwent age-related changes. Moreover our morphological findings can be correlated in relation to the clinical evolution of the sensitivity in the genital skin.

Cholinergic innervation of human mesenteric lymphatic vessels.

BACKGROUND: The cholinergic neurotransmission within the human mesenteric lymphatic vessels has been poorly studied. Therefore, our aim is to analyse the cholinergic nerve fibres of lymphatic vessels using the traditional enzymatic techniques of staining, plus the biochemical modifications of acetylcholinesterase (AChE) activity. MATERIALS AND METHODS: Specimens obtained from human mesenteric lymphatic vessels were subjected to the following experimental procedures: 1) drawing, cutting and staining of tissues; 2) staining of total nerve fibres; 3) enzymatic staining of cholinergic nerve fibres; 4) homogenisation of tissues; 5) biochemical amount of proteins; 6) biochemical amount of AChE activity; 6) quantitative analysis of images; 7) statistical analysis of data. RESULTS: The mesenteric lymphatic vessels show many AChE positive nerve fibres around their wall with an almost plexiform distribution. The incubation time was performed at 1 h (partial activity) and 6 h (total activity). Moreover, biochemical dosage of the same enzymatic activity confirms the results obtained with morphological methods. CONCLUSIONS: The homogenates of the studied tissues contain strong AChE activity. In our study, the lymphatic vessels appeared to contain few cholinergic nerve fibres. Therefore, it is expected that perivascular nerve stimulation stimulates cholinergic nerves innervating the mesenteric arteries to release the neurotransmitter AChE, which activates muscarinic or nicotinic receptors to modulate adrenergic neurotransmission. These results strongly suggest, that perivascular cholinergic nerves have little or no effect on the adrenergic nerve function in mesenteric arteries. The cholinergic nerves innervating mesenteric arteries do not mediate direct vascular responses.

Analysis of nerve supply pattern in human lymphatic vessels of young and old men.

BACKGROUND: The present work deals with innervation patterns along collector lymphatic vessels from cervical, mesenteric, and femoral regions, and lymph capillaries in young and elderly subjects. METHODS AND RESULTS: Morphological and morphometric analysis of nerve fibers along lymph vessels was performed by immunohistochemistry for PGP 9.5, NPY, TH, ChAT, VIP, SP, and dopamine. Nerves containing NPY and TH were frequent, whereas immunoreactivity for ChAT and VIP were few. SP-positive fibers were widely distributed in the medial and endothelial layers. Dopamine neurotransmitters were observed in a few short nerve fibers. A more diffuse presence of nerve fibers in mesenteric and femoral lymph vessels, compared to cervical ones, was detected. In lymph capillary vessels, a few nerve fibers positive for neuropeptides and neurotransmitters were detected, whereas no dopamine and VIP immunoreactive fibers were detected. A wide reduction of all specific nerve fibers analyzed was detected in lymph vessels from elderly subjects. CONCLUSIONS: The presence on lymph vessels of sympathetic and parasympathetic nerve systems can be declared. The differences observed in lymphatic vessel innervation patterns may note the involvement in lymph flow regulation, calling attention in aging, when nerve fibers reduction may cause functional default of lymph vessels.

Dopaminergic receptors in the human skin.

Dopamine is a neurotransmitter which plays an important role in many human organs including the skin. In this study we will examine the presence and the distribution of D1 and D2 dopamine receptors in a particular zone of the human skin. Samples of the human plantar skin were harvested during autopsies after the consent of relatives of the dead donors. In this study the following experimental procedures were performed: 1) drawing of the human plantar skin; 2) cutting of tissues; 3) staining of tissues; 4) staining of the nerve fibres; 5) radio-binding methods for labelling D1 and D2 dopamine receptors; 6) light microscope autoradiography; 7) quantitative analysis of images and 8) statistical analysis of data. The dopamine receptors D1 are distributed particularly in the dermis layer of the human plantar skin. They are numerous in lower epidermal layers (with exclusion of the corneal layer) and few in subcutaneous tissue. On the contrary D2 dopamine receptors are prominent in the subcutaneous tissue near the vessels. Quantitative analysis of images and statistical analysis of the data confirm all our results. The specific distribution of D1 and D2 dopamine receptors in the human plantar skin is in close relation with the functions of a particular zone of the human skin that supports the weight of all the body. Moreover the character of dopamine receptors distribution is very important for further understanding the role of these receptors in the human skin.

Role of dopaminergic receptors in the human dura mater in the pathogenesis of headache.

AIMS: We hypothesize that dopaminergic receptors of dura mater may play a possible role in headache. MATERIALS AND METHODS: The dopaminergic receptors of cranial dura mater in man were studied by examining several dural zones (vascular, peri-vascular, inter-vascular) in different brain regions (basal, calvarial, tentorial, occipital, frontal, parietal, temporal). RESULTS: Our results demonstrate that dopaminergic receptors are present in human cranial dura mater and that these receptors show a specific morphological location. There are more dural dopaminergic receptors in the basal region than in the calvarial one. Moreover, these receptors are more abundant in the vascular and perivascular dural zone than in the intervascular one. CONCLUSIONS: The location of dopaminergic receptors in the dura mater may represent an important factor in the pathogenesis of headache. Further studies will be necessary in order to determine the role of dopaminergic system in this disease.

Neuropeptides of human thymus in normal and pathological conditions.

Human thymus of healthy subjects and patients affected by thymoma-associated Myastenia Gravis were studied in order to visualize and compare the morphological distributive pattern of four neuropeptides: vasoactive intestinal peptide, substance P, neuropeptide Y, and neurotensin. Based on our observations, we formulated hypotheses on their relations in neuro-immunomodulation under physiological and pathophysiological conditions. Immuno-histochemical staining for neuropeptides was performed and morphological and morphometrical analyses were conducted on healthy and diseased thymus. In normal thymus, a specific distributive pattern was observed for the several neuropeptide-positive nerves in different thymus lobular zones. In particular substance P-positive fibers were observed in subcapsular zone, specifically located into parenchyma, where they represent the almost total amount of fibers; neurotensin-positive fibers were observed primarily located in parenchyma than perivascular site of several thymus lobular zones, and more abundant the cortico-medullary and medullary zones. Instead VIP- and NPY-positive fibers were widely distributed in perivascular and parenchymal sites of several thymus lobular zones. In thymoma, the distribution of neuropeptide-positive fibers was quantitatively reduced, while cells immunopositive to VIP and substance P were quantitatively increased and dispersed. Observation of the perivascular and parenchymal distribution of the analyzed neuropeptides suggests evidence that a regulatory function is performed by nerves and cells that secrete neuropeptide into the thymus. The alteration of neuropeptide patterns in thymoma suggests that these neurotransmitters play a role in autoimmune diseases such as Myastenia Gravis.

Density functional theory study of addition reactions of carbon-centered radicals to alkenes.

Addition reactions of carbon-centered radicals to unsaturated compounds have been studied using quantum chemistry. Following the review by Fischer and Radom (Angew. Chem., Int. Ed. 2001, 40, 1340.), the radicals were grouped in four different families, and the alkenes were selected from among those typical of polymer productions. All of the kinetic constants were calculated using density functional theory and classic transition state theory. Geometries of reactants, products, and transition states were determined at the B3LYP/6-311+G(d,p) level of theory, whereas reaction enthalpies, activation energies, and kinetic constants were estimated using different basis sets. By comparative evaluation of the results obtained with different basis sets, the best computational approach for each kinetic step was identified. As a result of this study, a computational methodology suitable for investigating a large number of kinetic pathways typical of free-radical polymerization processes is proposed.

Surgical technique to avoid bladder flap formation during cesarean section.

Cesarean section (CS) is now the most common major surgical procedure performed on women worldwide. A CS can be performed by either suturing or not suturing of the visceral peritoneum. Creation of the bladder flap is an integral step of the standard cesarean section. The bladder flap is made by superficially incising and dissecting the peritoneal lining to separate the urinary bladder from the lower uterine segment. It's still debated whether the formation of bladder flap is advantageous or not. If the uterine incision is made slightly above the vesicouterine peritoneal fold, the loose connective tissue between the uterus and the urinary bladder allows spontaneous descent of the bladder. Evidence on the role of the bladder flap in cesarean section is very limited. At present, it remains to be established whether there is any advantage in dissecting the bladder from the lower uterine segment during cesarean section.

RETRACTED: Intrinsic innervation and dopaminergic markers after experimental denervation in rat thymus.

The aim of this study was to examine rat thymus innervation using denervation techniques and to explore the related micro-anatomical localization of dopamine, D1, D2 receptors and dopamine membrane transporter (DAT). In the thymus subcapsular region, the parenchymal cholinergic fibers belong exclusively to phrenic nerve branching. No somatic phrenic nerve branching was detected in any other analysed thymus lobule regions. In rats subjected to sympathetic or parasympathetic ablation, it was observed that catecholaminergic and cholinergic nerve fibers respectively contributed to forming plexuses along vessel walls. In the subcapsular and septal region, no parenchymal nerve branching, belonging to sympathetic or parasympathetic nervous system was noted. Instead, in the deep cortical region, cortico-medullary junction (CM-j) and medulla, catecholaminergic and cholinergic nerve fibers were detected along the vessels and parenchyma. Dopamine and dopamine receptors were widely diffused in the lobular cortico-medullary junction region and in the medulla, where the final steps of thymocyte maturation and their trafficking take place. No variation in dopamine and DAT immune reaction was observed following total or partial parasympathectomy or phrenic nerve cutting. After chemical or surgical sympathectomy however, neither dopamine nor DAT immune reaction was noted again. Instead, D1 and D2 dopamine receptor expression was not affected by thymus denervation. In rats subjected to specific denervation, it was observed the direct intraparenchymal branching of the phrenic nerve and sympathetic and parasympathetic fibers into thymus parenchyma along vessels. These findings on the dopaminergic system highlight the importance of neurotransmitter receptor expression in the homeostasis of neuroimmune modulation.

The combination latanoprost-timolol versus twice daily 0.50% timolol administration either associated or not with latanoprost: efficacy and tolerability in the primary open-angle glaucoma.

AIMS: To evaluate the ocular hypotensive effects and tolerability of the once daily fixed combination latanoprost-timolol versus twice daily 0.50% timolol associated or not with once daily latanoprost in patients suffering from Primary Open-Angle Glaucoma (POAG). METHODS: We compared the effects of such a combination with those of 0.50% timolol alone twice daily in a group of 24 patients and with the effects of timolol 0.50% twice daily associated with once daily latanoprost in a second group of 20 patients with a follow-up of 24 months. RESULTS: In the first group of patients after one month the Intraocular Pressure (IOP) was reduced from a mean of 19.93 to a 17.04 mmHg. This reduction remained stable with a mean value of 17.00 mmHg at the third month, of 16.49 mmHg at the sixth month, of 17.04 at the twelfth month, 16.00 at the eighteenth month, and of 15.86 mmHg in the twenty-fourth month. In the second group there was a statistically significant reduction from 19.4 to 16.84 mmHg after one month. This reduction remained constant with mean values of 16.47 at the sixth month, of 16.20 at the twelfth month and of 16.00 mmHg at the twentyfourth month of treatment. CONCLUSIONS: The once daily latanoprost-timolol combination was shown to furtherly reduce the Intraocular Pressure (IOP) (p=0.001) and to maintain under control the intraocular pressure for the observation period (24 months). Both topical and systemic side-effects were scarse and tolerability was good.

Stickler syndrome in Pierre-Robin sequence prenatal ultrasonographic diagnosis and postnatal therapy: two cases report.

The Pierre-Robin Syndrome (PRS) is a rare congenital abnormality, with an approximately 1/30,000 estimated rate, characterized by the presence of the combination of mandibular hypoplasia (micrognathia or small jaw), glossoptosis (retrusion of the tongue into the pharyngeal airway) and, often, a posterior cleft of the secondary palate. It may be an isolated occurrence or part of a more complex syndrome and it is associated with long-term respiratory, nutritional, and developmental difficulties. Stickler syndrome (SS) is a rare autosomal dominant connective tissue disorder estimated to affect approximately 1/7500 newborns. It is diagnosed clinically and, at present, there is no consensus on a minimal clinical diagnostic criterion. The most frequent diagnosis in patients with syndromic Pierre Robin sequence is Stickler syndrome, which may be complicated by congenital high myopia and substantial risk of retinal detachment. However, cases of Stickler syndrome with probable visual complications are rarely identified among this group of patients by members of the cleft team. The patient had an acute unilateral hydrops, with a monolateral keratoconus. The ocular abnormalities included: severe myopia, abnormalities of the vitreous, and high risk of retinal detachment (with subsequent blindness). We report two extremely rare cases of prenatal diagnosis of PRS and SS, prematurely identified by prenatal ultrasonography and successively managed by oculists ophthalmogists.

Structural characterization of a Protein A mimetic peptide dendrimer bound to human IgG.

Understanding the chemical physical properties of protein binding sites is at the basis of the rational design of protein ligands. The hinge region of the Fc fragment of immunoglobulin G is an important and well characterized protein binding site, known to interact with several natural proteins and synthetic ligands. Here, we report structural evidence that a Staphylococcus aureus Protein A mimetic peptide dendrimer, deduced by a combinatorial approach, binds close to the Cgamma2/Cgamma3 interface of the constant fragment of a human IgG1 molecule, partially hindering the Protein A binding site. The X-ray analysis evidenced a primary binding site located between a terminal Arg residue of the ligand peptidic arm and a hydrophobic protein site consisting of Val308, Leu309, and His310. A molecular dynamic analysis of the model derived from the X-ray structure showed that in water at room temperature the complex is further stabilized by the formation of at least one more contact between a terminal Arg residue of the second arm of the peptide and the carboxylic group of a protein amino acid, such as Glu318, Asp312, or Asp280. It appears thus that stability of the Fc-dendrimer complex is determined by the synergetic formation of multiple bonds of different nature between the dendrimer arms and the protein accessible sites. The electrostatic and van der Waals energies of the complex were monitored during the MD simulations and confirmed the energetic stability of the two interactions.

[Pancreaticoduodenectomy for adenocarcinoma of the pancreatic head and papilla of Vater]. / Duodenocefalopancreatectomia per adenocarcinoma della testa del pancreas e della papilla di Vater.

AIM: The authors report their consecutive experience in the surgical management of adenocarcinoma (ADC) of head of pancreas and papilla of Vater, in order to review the available literature. METHODS: One hundred and seventy cases (131 in the head of pancreas and 39 in the papilla of Vater) were operated upon for ADC by radical pancreaticoduodenectomy in the period 1972-2005. The stomach was resected in 81 patients (47.7%) and the pylorus was preserved in 89 (52.3%). Follow-up was completed in all patients. RESULTS: Postoperative morbidity was reported in 66 patients (38.8%) and pancreatic fistulae were observed in 39 patients (22.9%). Postoperative mortality was 9.4% (16 patients), but in the last 10 years it was reduced to 4.1% (4/97 patients). Five-year survival for pancreatic ADC was 75% in stage IA, 43.9% in stage IB and IIA, 3.2% in stage IIB. In ADC of the papilla of Vater, for the same stages, the 5-year survival rates were 54.4%, 51.4%, 0% and 37.5%, respectively. None of the III-staged patients survived at a 5-year follow-up in both groups. CONCLUSIONS: Preoperative studies should include laparoscopy with cytological examination of peritoneal lavage, while preoperative biliary drainage is rarely indicated in case of obstructive jaundice. The Wirsung duct has to be anastomosed directly to the jejunum and the pancreatic section needs to be checked. Extended lymphadenectomy, in addition to the standard peripancreatic excision, is seldom indicated, there is no controindication to pylorus preservation and Wirsung drainage is not necessary. This operation should be performed in Centres with substantial experience.

Dopamine nerve fibres and related receptors in bronchus-associated lymphoid tissue (BALT).

Age-related changes of the dopamine nerve fibres of bronchus associated lymphoid tissue (BALT) were investigated in male Wistar rats of 3 months (young), and 24 months (old/aged). Dopamine histofluorescence techniques have been used, associated with image analysis for the detection of dopamine nerve fibres. In young rats, white, fluorescent nerve fibres supply BALT. This tissue is innervated by a delicate network of nerve fibres rich in varicosities. In old rats these fluorescent nerve fibres are strongly reduced. Moreover, dopamine D1a and D1b receptors were stained using fluorescent monoclonal antibodies. The BALT of young rats possesses a higher number of D1a and D1b receptors, while, in the old rats, these receptors are strongly reduced. The possible significance of reduced dopamine neurotransmission in BALT of aged rats is discussed.

Diabetic rats treated by low molecular weight heparin OP 2123/parnaparin: morphological changes in the kidney and heart.

AIM: Early morphological alterations in the rat kidney and heart due to experimentally induced diabetes are described in order to evaluate the possible therapeutic role of low molecular weight heparin (LMWH; OP 2123/parnaparin). METHODS: Our findings concern the alterations observed in the rat kidney and heart because these are the organs (together with the retina) mainly involved in the early morphological angiopathic modifications associated with diabetic damage of organs and tissues. In diabetic animals treated with LMWH, the Periodic Acid-Schiff (PAS) reaction showed a slight decrease when compared with the diabetic control group. Photographs were submitted to the quantitative analysis of images using a Quantimet 500 Image Analyzer (Leica) equipped with specific software. The following parameters were measured: (1) total area occupied by alkaline phosphatase (AP)-positive capillaries; (2) number and diameter of AP-positive capillaries; (3) distribution and total area occupied by PAS-positive structures (related to the intensity of the reaction resulting from the different amount of mucopolysaccharides). RESULTS: LMWH treatment is efficient in preventing these modifications, above all in the kidney. The histological study of the heart and kidney shows no significant, relevant alterations. However, the histological study of the mucopolysaccharides in diabetic animals highlighted a tendency for the heart to accumulate these substances. LMWH treatment only modestly reduced this accumulation. CONCLUSIONS: Previous evidence demonstrating a beneficial effect of therapy based on heparan sulphate proteoglycans and/or other heparin-like substances in insulin-dependent diabetes mellitus seems to be confirmed by our experimental results in different organs of adult rats. In fact, parnaparin treatment is effective (in our experience) for ameliorating the morphological pattern observed early in some diabetic tissues of rats and, above all, in the kidney.