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Diabetic gastroparesis corresponds to symptomatic as well as asymptomatic gastric retention without organic abnormality of stomach, pylorus or gut. This complication associated with autonomic neuropathy is found in about 50% of patients with type 1 and type 2 diabetes. It may be clinically important when it is associated with gastrointestinal symptoms limiting quality of life, alterations in glycaemic control and changes in oral drug absorption. In addition, acute changes in blood glucose concentration affect gastric motor function: gastric emptying is slowed down during hyperglycaemia and accelerated during hypoglycaemia. The diagnosis of gastroparesis may be confirmed by scintigraphy assessment of gastric emptying, preferably using a solid meal. Unfortunately, treatment options remain limited and often unsatisfactory. They first rely on life-style and dietary modifications. If necessary, pharmacological agents (metoclopramide, domperidone, cisapride, and erythromycin) may be considered. Cisapride is actually the most powerful agent for chronic use, but the risk of cardiac toxicity (increase of QT with "torsade de pointe") limits its general use. In some diabetic patients, gastroparesis may contribute to erratic glucose excursions, with precocious postprandial hypoglycaemia, late hyperglycaemia, and/or delayed recovery from hypoglycaemia after carbohydrate ingestion. Sometimes, the initiation of intensive insulin therapy and the use of prokinetic drugs could lead to significant improvement of blood glucose control in patients with diabetic gastroparesis.

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Chicken gizzard smooth muscle has often been used as a source of proteins of the contractile and cytoskeletal apparatus. In the present study, we isolated a hitherto unknown doublet of proteins, with apparent molecular weights of 200 kDa, from embryonic chicken gizzard and showed its association with the microtubules (MTs) and by immunofluorescence staining of cultured cells. Immunoblot analysis also revealed the ubiquitous expression of this protein in all embryonic chicken tissues examined. Molecular cloning techniques allowed its identification as the chicken homologue of the microtubule-associated protein 4 (MAP4), known from mammalian species, and revealed approximately 90% of its amino acid sequence. MAP4 is the major MAP of non-neuronal tissues and cross-species comparisons clearly demonstrated its highly conserved overall structure, consisting of a basic C-terminal MT-binding region and an acidic N-terminal projection domain of unknown function. Despite these conserved features, overall sequence homologies to its mammalian counterparts are rather low and focused to distinct regions of the molecule. Among these are a conserved 18-amino acid motif, which is known to mediate binding to MTs and a part of the MT-binding domain known as the proline-rich region, which is thought to be the regulatory domain of MAP4. The N-terminal 59 amino acids are a conserved and unique feature of the MAP4 sequence and might be an indication that MAP4 performs other functions besides the enhancement of MT assembly.

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Since 1978, the authors have observed 7 cases of dissecting aneurysm in the internal carotid artery. Symptoms were severe headache and subsequent neurologic deficit in young persons (3 women, 4 men; mean age 35 years). The underlying pathology was spontaneous dissection of the cervical internal carotid artery, with surgical confirmation in 3 cases and typical angiographic patterns in all cases. Spontaneous dissection of the cervical internal carotid artery is being increasingly recognized as a cause of cerebral ischemia in young adults. Moreover this clinicopathologic event is more common than had previously been supposed. The etiology remains unclear, except in 15% of cases in which dystrophy of the media (Marfan's syndrome) is in cause. No history of cervical trauma can be found. Typical clinical features consist in ipsilateral headache preceding an abrupt neurologic deficit in a 40-year-old person. An incomplete Horner syndrome (oculosympathetic paresis without facial anhidrosis) associated with facial pain and numbness is pathognomonic, but the majority of dissections are less typical. The typical angiographic pattern is an elongated regular stenosis of the high cervical internal carotid artery, 2 cm above the non-involved bulbus ("string sign"). The dissection may modify to a tapered occlusion above the point of origin of the internal carotid artery. The natural course is spontaneous resolution of the stricture, without relapse. Optimal management is non-operative since medical treatment has proved to be efficient. These cases confirm the benign course and overall good prognosis of spontaneous dissections of the internal carotid artery which are not as rare as the scarcity of reports might indicate.(ABSTRACT TRUNCATED AT 250 WORDS)

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