Hemorrhagic shock from post-traumatic rupture of microcystic splenic lymphangioma: A case report and review of the literature.

INTRODUCTION: Lymphangioma is an abnormal proliferation of lymphatic vessels. Isolated splenic lymphangioma (SL) is rare; in the last 30 years only 22 cases were reported in the literature. Diagnosis is difficult by the absence of typical symptoms and signs. SL is often asymptomatic and occasionally detected through radiological exams or, after the onset of a life-threatening complication, at surgery or pathological examination. Surgery represents the treatment of choice. PRESENTATION OF CASE: A 22-year-old Caucasian male was admitted to the Emergency Department after a car accident, complaining of sudden onset, severe, left upper quadrant abdominal pain. Abdominal examination revealed mild abdominal distention and a severe abdominal pain on superficial and deep palpation of left upper abdominal quadrant with obvious muscle guarding and rebound tenderness. Abdominal computed tomography scan showed splenic rupture with hemoperitoneum. Laboratory tests reported severe anemia. The patient received blood transfusions and was taken emergently to the operating room for exploratory laparotomy, evacuation of hemoperitoneum and splenectomy. The postoperative course was uneventful, the patient was discharged on the 7th post-operative day. Diagnosis of microcystic SL was made at pathological examination. DISCUSSION: Post-traumatic splenic rupture may be favored by the presence of a unknown and asymptomatic isolated SL. Although different types of treatment of SL are reported in the literature, splenectomy represents the treatment of choice to avoid complications. CONCLUSION: Isolated SL is difficult to diagnose and suspect because of lack of pathognomonic symptoms and specific diagnostic signs. It can be diagnosed after the onset of a life-threatening complication. Splenectomy is the preferable definitive treatment.

5'-Spiro-cyclopropanated lactose derivatives as suitable intermediates for the chain elongation: synthesis of a new 6-deoxy-6-methyl δ-eptulose.

A δ-dicarbonyl heptose has been prepared through an electrophilic ring opening procedure of a 5'-spirocyclopropanated lactose derivative. The reported synthetic procedure outlines a new route for the transformation of this renewable disaccharide into new and interesting δ-dicarbonyl sugars, synthetic precursors of cyclitols, carba- and azasugars. The experimental results of the cyclopropanation process have been successfully rationalized by in silico studies.

Synthesis and physico-chemical characterization of a ß-cyclodextrin conjugate for sustained release of Acyclovir.

We report the synthesis of an oligomeric prodrug of the antiviral agent Acyclovir (Acy) conjugated to ß-cyclodextrin (ß-CyD). The drug was selectively linked through a succinic spacer to one of the primary hydroxyl groups of ß-CyD by ester linkage in a 1:1 molar ratio. The conjugate was purified by semipreparative reverse-phase chromatography and characterized by FAB mass spectrometry and NMR experiments. The release of Acy from the conjugate was evaluated both in acidic and in neutral conditions and in the presence of porcine liver esterase. In all cases we observed the release of both free Acy and Acy succinate (AcySucc) at differing rates as a function of the hydrolysis conditions. In the presence of esterase the release of free Acy was favoured over AcySucc, showing a release rate of 100% of Acy within 7 days.

Syntheses of isoxazoline-carbocyclic nucleosides and their antiviral evaluation: a standard protocol.

The current synthesis of racemic purine and pyrimidine isoxazoline-carbocyclic nucleosides is reported, detailing the key-steps for standard and reliable preparations. Improved yields were obtained by the proper tuning of the single synthetic steps, opening the way for the preparation of a variety of novel compounds. Some of the obtained compounds were also evaluated against a wide variety of DNA and RNA viruses including HIV. No specific antiviral activity was observed in the cases at hand. Novel compounds were prepared for future biological tests.

A prospective, randomized trial comparing the short- and long-term results of doppler-guided transanal hemorrhoid dearterialization with mucopexy versus excision hemorrhoidectomy for grade III hemorrhoids.

BACKGROUND: Few randomized trials have compared the results of Doppler-guided transanal hemorrhoid dearterialization with mucopexy and excisional open hemorrhoidectomy. Few studies have reported long-term results. OBJECTIVE: The aim of this study is to evaluate the results of Doppler-guided transanal hemorrhoid dearterialization with mucopexy compared with excisional open hemorrhoidectomy in patients with grade III hemorrhoids. DESIGN: This is a prospective randomized study registered at clinicaltrials.gov (NCT01263431). A power analysis assessed the study's sample size. Patients were randomly assigned to undergo either hemorrhoidectomy or Doppler-guided hemorrhoid dearterialization plus mucopexy. The χ test, Mann-Whitney U test, Student t test, and a regression model were used, as appropriate. SETTINGS: This study was conducted at the Department of Surgery, San Raffaele Scientific Institute, Milan, Italy. PATIENTS: Fifty consecutive patients were treated for grade III hemorrhoids from July to November 2010. MAIN OUTCOME MEASURES: The primary outcome was postoperative pain. The secondary outcomes included postoperative morbidity, the resumption of social and/or working activity, patient satisfaction, and the relapse of symptoms at 1 and 24 months. RESULTS: No major complications occurred in either group. The median visual analog scale scores for pain in the hemorrhoidectomy and Doppler-guided dearterialization plus mucopexy groups on days 1, 7, 14, and 30 were 7 vs 5.5, 3 vs 2.5, 1 vs 0, and 0 vs 0 (p> 0.05). The median work resumption day was the 22nd in the hemorrhoidectomy group and the 10th in the Doppler-guided dearterialization plus mucopexy group (p = 0.09). Patient satisfaction at 1 and 24 postoperative months, with the use of a 4-point scale, was 3 vs 4 and 4 vs 4 (p > 0.05). During the follow-up, 2 patients in the dearterialization group required ambulatory treatment, and 1 patient in each group required further surgery for symptom relapse. LIMITATIONS: Nonvalidated questionnaires were used in the follow-up. Cost analysis was not performed. CONCLUSION: Compared with hemorrhoidectomy, dearterialization with mucopexy resulted in similar postoperative pain and morbidity, and a similar long-term cure rate.

Recent advances in small organic molecules as DNA intercalating agents: synthesis, activity, and modeling.

The interaction of small molecules with DNA plays an essential role in many biological processes. As DNA is often the target for majority of anticancer and antibiotic drugs, study about the interaction of drug and DNA has a key role in pharmacology. Moreover, understanding the interactions of small molecules with DNA is of prime significance in the rational design of more powerful and selective anticancer agents. Two of the most important and promising targets in cancer chemotherapy include DNA alkylating agents and DNA intercalators. For these last the DNA recognition is a critical step in their anti-tumor action and the intercalation is not only one kind of the interactions in DNA recognition but also a pivotal step of several clinically used anti-tumor drugs such as anthracyclines, acridines and anthraquinones. To push clinical cancer therapy, the discovery of new DNA intercalators has been considered a practical approach and a number of intercalators have been recently reported. The intercalative binding properties of such molecules can also be harnessed as diagnostic probes for DNA structure in addition to DNA-directed therapeutics. Moreover, the problem of intercalation site formation in the undistorted B-DNA of different length and sequence is matter of tremendous importance in molecular modeling studies and, nowadays, three models of DNA intercalation targets have been proposed that account for the binding features of intercalators. Finally, despite DNA being an important target for several drugs, most of the docking programs are validated only for proteins and their ligands. Therefore, a default protocol to identify DNA binding modes which uses a modified canonical DNA as receptor is needed.

Prevalence of oxetanose forms in the tautomeric equilibrium of ß-hydroxy-1,5-dicarbonyl monosaccharides.

The synthesis of 4-deoxy- and 4-deoxy-4-C-methylhexos-5-uloses, starting from 4-deoxyhex-4-enopyranosides, and a nuclear magnetic resonance (NMR) study of their isomeric composition are reported. The NMR spectra show that the two δ-dicarbonyl sugars exist as two anomeric α- and ß-oxetanosyl forms, derived from the hemiacetalization of the C-3 hydroxyl group with the aldehydic carbon. The observed tautomeric equilibria have been rationalized with computational calculations. Interestingly, this is the first time that dicarbonyl derivatives are mostly present in their oxetanose forms, offering a new entry into this very interesting type of scaffold.

Synthesis and biological evaluation of furopyrimidine N,O-nucleosides.

A series of modified N,O-nucleosides, characterized by the presence of a furopyrimidine moiety, has been synthesized by exploiting a Sonogashira cross coupling reaction of 1-isoxazolidinyl-5-iodouracil with alkynes, followed by treatment with CuI in refluxing TEA/MeOH mixture. The obtained compounds were screened against both RNA and DNA viruses. None of the compounds were endowed with antiviral activity at subtoxic concentrations. However, some of them were able to inhibit proliferation of MRC-5, Vero, BS-C-1 cells by 50% (CC50) at concentrations ranging from 0.7 to 62.5 mM.

Isoxazolidinyl polycyclic aromatic hydrocarbons as DNA-intercalating antitumor agents.

The second generation and an isosteric series of isoxazolidinyl polycyclic aromatic hydrocarbons, as DNA-intercalator agents designed to act on remotely implanted tumors, have been synthesized in good yields according to the 1,3-dipolar cycloaddition methodology. The structure of the obtained cycloadducts has been determined by NOE experiments and supported by computational studies at PM3 level. The utility of this new template in the synthesis of structures designed to capitalize on its intercalative properties has been examined. All the obtained compounds have been tested for their in vitro cytotoxic activity and the most potent of them showed an IC(50) of 9 µM upon the human lung cancer (A-549) cell and a binding constant, for the intercalation with calf thymus DNA, of 9.6 × 10(4) M(-1). Biological and docking studies showed that these compounds complex exclusively by intercalation between base pairs, approaching the DNA from its minor groove, with a neat selectivity for the AT or GC nucleobases.

Towards the synthesis of new dideoxy delta-dicarbonyl heptoses.

The preparation of a delta-dicarbonyl sugar thorough ring-opening, by a methoxymercuration-demercuration procedure, of a 5-spirocyclopropanated d-galactose derivative, is reported. This method constitutes a new route for the transformation of a hexose into new and interesting delta-dicarbonyl sugars, synthetic precursors of cyclitols, carba- and azasugars. Moreover this is, to our best knowledge, the first reported example of an elongation to a higher sugar starting from a spirocyclopropanated saccharide.

Synthesis and biological activity of isoxazolidinyl polycyclic aromatic hydrocarbons: potential DNA intercalators.

Isoxazolidinyl polycyclic aromatic hydrocarbons (isoxazolidinyl-PAHs) have been synthesized in good yields by 1,3-dipolar cycloaddition methodology promoted by microwave irradiation. The structures of the obtained cycloadducts have been determined by NOE experiments and supported by computational studies at the AM1 level. The cytotoxicity and antiviral activity of the synthesized compounds have been investigated. In particular, compounds 7c and 7e show high levels of cytotoxicity on MOLT-3 leukemia cells; 7e exerts a remarkable enhancing activity on apoptosis caused by anti-fas antibody addition. Furthermore, compounds 7b and 8b exhibit specific antiviral effects against the Punta Toro virus.

Preparation of celecoxib-dimethyl-beta-cyclodextrin inclusion complex: characterization and in vitro permeation study.

The ability of 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-Cyd) to include the anti-inflammatory drug celecoxib (CCB) was evaluated. The complex was prepared by kneading and freeze-drying methods and was characterized in the solid state and in aqueous solution. Water solubility and dissolution rate of CCB, in a medium simulating gastric fluid, significantly increased after complexation, with complete dissolution obtained after 30 and 180 min for the freeze-dried and kneaded complexes respectively. Phase solubility studies showed Ap-type diagrams. Stability constants for the 1:1 and 1:2 CCB-DM-beta-Cyd complexes and (1)H-NMR studies suggested a probable 1:1 inclusion complex and only an external interaction for the second Cyd molecule. Thermodynamic parameters of the binding process showed the existence of van der Waals forces between CCB and DM-beta-Cyd. DM-beta-Cyd influenced the permeation of CCB through the CaCo-2 cells monolayer. The increase of permeation observed was due to the fast dissolution rate of the included drug and to a destabilizing action exerted by the macrocycle on the biomembrane.

Convenient preparation of L-arabino-hexos-5-ulose derivatives from lactose.

2,6-di-O-benzyl- (9), 2-O-benzyl-3,4-O-isopropylidene- (19), and 2-O-benzyl-6-O-m-chlorobenzoyl-L-arabino-hexos-5-ulose (20) have been prepared using 4'-deoxy-4'-eno- and 6'-deoxy-5'-eno lactose dimethyl acetal derivatives 7 and 14 as key intermediates. The synthesis of enol ethers 7 and 14 has been performed with good yields by base-promoted elimination of acetone or p-toluenesulfonic acid from 2',6'-di-O-benzyl-, and 6'-O-p-toluenesulfonyl-2,3:5,6:3',4'-tri-O-isopropylidenelactose dimethyl acetal, respectively. The epoxidation with MCPBA of 7 and 14 in methanol or dichloromethane furnishes C-5'-methoxy and C-5'-m-chlorobenzoyloxy derivatives, easily transformed with good yields into L-arabino 5-ketoaldohexoses 9, 19 and 20.

A new route for the chemical valorisation of lactose.

A totally protected di-O-benzyl derivative of triacetonlactose dimethyl acetal was transformed into a 4'-hexeno disaccharide by elimination of acetone with t-BuOK in DMF and subsequently in 5'-C-methoxy derivative by oxidation with MCPBA in methanol as a solvent. The hydrolysis of this latter compound affords 2,6-di-O-benzyl-L-arabino-aldohexosos-5-ulose, which by intramolecular aldol condensation with DBU gives an inosose that was stereoselectively reduced to epi-inositol. Therefore our synthetic strategy offers a new and simple method to transform lactose into carbocyclic monosaccharide analogues.

Enantioselective syntheses and cytotoxicity of N,O-nucleosides.

Enantiomers of 4'-aza-2',3'-dideoxynucleosides have been prepared by two different synthetic approaches, on the basis of 1,3-dipolar cycloaddition of a chiral nitrone. Cytotoxicity and apoptotic activity have been investigated. (5'S)-5-Fluoro-1-isoxazolidin-5-yl-1H-pyrimidine-2,4-dione [(-)-AdFU], while showing low level of cytotoxicity, is a good inductor of apoptosis on lymphoid and monocytoid cells, acting as a strong potentiator of Fas-induced cell death.

Intramolecular aldol cyclization of L-lyxo-hexos-5-ulose derivatives: a new diastereoselective synthesis of D-chiro-inositol.

The DBU-promoted intramolecular aldol condensation of two partially protected L-lyxo-hexos-5-ulose derivatives (8 and 9), in turn obtained starting from methyl beta-D-galactopyranoside, takes place with fairly good yield and complete diastereoselectivity to give 2L-(2,3,6/4,5)-pentahydroxycyclohexanone derivatives, 10 and 11. The stereoselective reduction of inosose 10 with sodium triacetoxyborohydride leads, after catalytic debenzylation, to D-chiro-inositol (1), while the sodium borohydride reduction furnishes, with opposite stereoselectivity, a derivative of allo-inositol.

Intramolecular cycloadditions of alpha-allyloxycarbonylnitrones: stereoselective synthesis of 3-amino-2(5H)furanones.

Treatment of furoisoxazolidines with NaH leads to functionalized 3-amino-2(5H)-furanones through a new rearrangement pattern of the isoxazolidine nucleus. This process has been usefully exploited for the synthesis of enantiomerically pure (5R)-3-alkylamino-5-methyl-2(5H)-furanones.