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Background: The calcifying odontogenic cyst (COC) is a rare pathological entity. It falls into a group of lesions with calcifications that present benign and sometime malignant tumor variants. Case Presentation: In the present study, we report on a case of intraosseous/intrasinusal COC with impacted maxillary canine and dentinoid structures odontoma-like. The clinical, radiographical, histopathological, and molecular characteristics of this pathological entity are discussed in relation also to the problems of differential diagnosis, treatment, and prognosis. Conclusion: The true COC is a rare entity in the oral cavity and represents about less than 1% of all odontogenic lesions. Careful clinical, instrumental and histological analysis must be performed for odontogenic cysts in order to accomplish the correct surgical act and to avoid recurrence.

This article includes a comprehensive and up-todate review on the cysts of the oral cavity. Several classifications of odontogenic (OC) and non-odontogenic (non- OC) oral cysts and the surrounding regions have been proposed. We suggest a new critical classification based on an established relationship between anatomical area, histological origin and clinical behavior (frequency, rate of recurrence, malignant potential). Moreover, the differential cytokeratin (CKs) expression of the various cysts is reported as epitheliumspecific markers of differential diagnosis. Finally, issues related to differential diagnosis and therapeutic approaches of the cysts included in the two groups are described. This article includes a comprehensive and up-todate review on the cysts of the oral cavity. Several classifications of odontogenic (OC) and non-odontogenic (non- OC) oral cysts and the surrounding regions have been proposed. We suggest a new critical classification based on an established relationship between anatomical area, histological origin and clinical behavior (frequency, rate of recurrence, malignant potential). Moreover, the differential cytokeratin (CKs) expression of the various cysts is reported as epitheliumspecific markers of differential diagnosis. Finally, issues related to differential diagnosis and therapeutic approaches of the cysts included in the two groups are described.

Kissing molars (KMs) is an extremely rare condition of impacted third molars, pointed in the opposite direction in a single follicular space; it consists exactly in a full impacted of permanent molars which occurs only in the lower jaw. Actually, about less than thirty cases have been reported in scientific literatures. The aetiology and pathogenesis of this pathological double dental inclusion remain unknown; above all events that lead two molars to appear, as KMs remain mysterious. The association to metabolic connective diseases such as mucopolysaccharidosis was emphasized. KMs considered as an isolated event, may be associated to an abnormal position of the tooth-bud from lower permanent molars, or fourth supernumerary tooth (distomolar). Recently, hyperplastic dental follicle (HDF), with a down regulation of matrix metal-proteinases and up regulation of several genes of collagens, has been mentioned in association with KMs. In this paper, after having analyzed three new cases of KMs that have been treated, we report a new hypothesis. This last is based on the failure in the dental follicle’s ability to initiate or continue properly resorption of the overlying alveolar bone, by many exogenous factors which may act on eruptive phase that would lead to its rotation with its contents coming out a pathological situation of KMs. The therapy of choice is related to the surgical removal of KMs through a double odontectomy with transalveolar method. Other treatments can be, eventually, orthodontic therapy of the impacted teeth and a radiological follow-up without surgery.

A wide number of gastro-intestinal disorders are associated with structural alterations of this district leading to an impaired gastrointestinal function. The study of cell material interactions represents one of the major issues for the development of tissue engineering purposes. Benzyl esters of hyaluronic acid are promising materials because they exhibit good tissue compatibility and are available in various configurations. In this work they have been studied for the possible application of intestinal cell growth and functioning. The preliminary investigation on the morphologic and biochemistry data obtained by monitoring the growth and differentiation of intestinal epithelial cells on two hyaluronic acid benzyl esters is reported. Two types of materials structures were studied: a three dimensional matrix and a macroporous flat sheet membrane. Caco-2 cell line was used: these cells undergo spontaneous enterocytic differentiation after several days in culture. The differentiation status of these cells grown on different materials was used as a parameter of biocompatibility and cell functioning. The status of cell growth and differentiation was monitored by studying cell morphology using scanning electron microscopy. The results obtained were confirmed by biochemical determinations. Although both the configurations of the two polymers exhibited good compatibility with respect to intestinal cells, only the flat sheet membrane proved to induce cell differentiation, leading us to the conclusion that it is a promising substrate for the proposed application.

The apomyoglobin mutant W7FW14F forms amyloid-like fibrils at physiological pH. We examined the kinetics of fibrillogenesis using three techniques: the time dependence of the fluorescence emission of thioflavin T and 1-anilino-8-naphthalenesulfonate, circular dichroism measurements, and electron microscopy. We found that in the early stage of fibril formation, non-native apomyoglobin molecules containing beta-structure elements aggregate to form a nucleus. Subsequently, more molecules aggregate around the nucleus, thereby resulting in fibril elongation. We evaluated by MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) the cytotoxicity of these aggregates at the early stage of fibril elongation versus mature fibrils and the wild-type protein. Similar to other amyloid-forming proteins, cell toxicity was not due to insoluble mature fibrils but rather to early pre-fibrillar aggregates. Propidium iodide uptake showed that cell toxicity is the result of altered membrane permeability. Phalloidin staining showed that membrane damage is not associated to an altered cell shape caused by changes in the cytoskeleton.

Myoglobin is an alpha-helical globular protein that contains two highly conserved tryptophan residues located at positions 7 and 14 in the N-terminal region of the protein. Replacement of both indole residues with phenylalanine residues, i.e. W7F/W14F, results in the expression of an unstable, not correctly folded protein that does not bind the prosthetic group. Here we report data (Congo red and thioflavine T binding assay, birefringence, and electron microscopy) showing that the double Trp/Phe replacements render apomyoglobin molecules highly susceptible to aggregation and amyloid-like fibril formation under physiological conditions in which most of the wild-type protein is in the native state. In refolding experiments, like the wild-type protein, the W7F/W14F apomyoglobin mutant formed a soluble, partially folded helical state between pH 2.0 and pH 4.0. A pH increase from 4.0 to 7.0 restored the native structure only in the case of the wild-type protein and determined aggregation of W7F/W14F. The circular dichroism spectrum recorded immediately after neutralization showed that the polypeptide consists mainly of beta-structures. In conclusion, under physiological pH conditions, some mutations that affect folding may cause protein aggregation and the formation of amyloid-like fibrils.

Clinical Practice Points Tumors originating from vestigial Mullerian cells embedded in the peritoneum could give rise to a primitive, peritoneal, mixed neoplasia with a predominant myoid differentiative trait and a double mesenchymal component. When possible, the most adequate treatment involves the en bloc resection of the mass together with the pelvic, parietal, and diaphragmatic peritoneum, and omentum, uterus, and annexes. The surgical treatment should be completed with the removal of the bulky right and left iliac lymph nodes. The components of the Mullerian ducts that do not undergo processes of differentiation and organogenesis constitute the secondary Mullerian system, from which various proliferative disorders might originate, such as endometriosis, endosalpingiosis, and endocervicosis. Epithelial-like cancers can also originate from the secondary Mullerian system, such a serous, mucinous, and endometrioid hystotypes.

This study reports the effects of the nucleoside analogs dideoxyinosine (DDI) and 3'-azido-3'-deoxythymidine (AZT) on mammalian embryonic development. When administered to pregnant mice (at concentrations ranging from 10 to 300 mg/kg/day), through all or part of gestation, AZT and DDI did not result in any visible effect on mouse embryos nor did they cause any obvious malformation or defect at birth or during postnatal growth. Similarly, when embryonic or fetal mouse or human cells (from brain, limb buds, or different organ rudiments) were exposed to AZT or DDI in vitro, cytotoxicity was observed only in the mM range, with AZT showing slightly higher cytotoxicity and brain cells appearing slightly more sensitive to both nucleosides. However, even in cultures treated with very high concentrations of AZT or DDI, the reduction in the number of terminally differentiated skeletal myotubes, cardiocytes, neurons, and chondrocytes was similar to the reduction in the total number of cells, indicating that AZT and DDI did not selectively inhibit differentiation of any of the above-mentioned cell types. Finally, preimplantation mouse embryos (at the 2-cell or 4-cell stage), treated in vitro with micromolar concentrations of AZT, were arrested at the 4-cell stage. DDI or other nucleoside analogs tested did not have this effect.

Fibrous histiocytoma is a benign soft tissue tumour arising as a fibrous mass everywhere in the human body. The involvement of the oral cavity is rare. We report two cases of benign fibrous histiocytoma that localized in the oral cavity. The clinical and histological features of the lesion are reported. Finally, a literature revision of this pathology at the level of the oral cavity is reported.

John Allen, a British physician of the eighteenth century, deserves being remembered for a series of inventions, but most importantly -- from a 'medical' point of view -- for his highly praised manuscript, the 'Universae Medicinae Practicae,sive Doctissimorum Virorum de Morbis Eorumque Causis ac Remediis Judicia', which long served as a text-book for medical students of the time, and also as a reference book for practitioners throughout European countries, for several decades after its original first publication. It contains the opinions ('Sententiae') of the most celebrated authors of all ages, from Hippocrates, Galen and Avicenna up to Allen's contemporaries, concerning a wide number of diseases, their causes, signs, symptoms, and therapeutical remedies where available. The present paper deals mostly with parts of the Synopsis concerning renal diseases and related clinical signs.

The many progressive achievements in knowledge about the structure and function of the nephron – the kidney’s main morpho-functional unit – have always been influenced by philosophical theories, which for a long time have swung between vitalism and mechanism. From Galen’s first imaginative vitalistic hypothesis, the scientific thought about the kidney’s structure/function gradually moved to the iatro-mechanistic view promoted by Borelli, Bellini and Malpighi, to then meet Bowman’s bright vitalistic-based theory. But Bowman’s theory was rather soon replaced by novel yet still mechanistic theories proposed first by Ludwig and then Starling. Ludwig based his scientific approach to knowledge of renal function upon physics and chemistry; Starling eventually developed a ‘colloid-osmotic’ theory.