Are chemokines the third major system in the brain?

Chemokines are a family of small proteins involved in cellular migration and intercellular communication. Although the chemokines and their receptors are located throughout the brain, they are not distributed uniformly. Among the chemokines and their receptors that are arrayed disproportionately in glia and neurons are monocyte chemotactic protein-1/CC chemokine ligand 2 (CCL2), stromal cell-derived factor-1/CXC chemokine ligand 12 (CXCL12), fractalkine/CX3C chemokine ligand 1, interferon-gamma-inducible-protein-10/CXCL10, macrophage inflammatory protein-1alpha/CCL3, and regulated on activation, normal T cell expressed and secreted/CCL5. In the brain, they are found in the hypothalamus, nucleus accumbens, limbic system, hippocampus, thalamus, cortex, and cerebellum. The uneven distribution suggests that there may be functional roles for the chemokine "system," comprised of chemokine ligands and their receptors. In addition to anatomical, immunohistochemical, and in vitro studies establishing the expression of the chemokine ligands and receptors, there is an increasing body of research that suggests that the chemokine system plays a crucial role in brain development and function. Our data indicate that the chemokine system can alter the actions of neuronally active pharmacological agents including the opioids and cannabinoids. Combined with evidence that the chemokine system in the brain interacts with neurotransmitter systems, we propose the following hypothesis: The endogenous chemokine system in the brain acts in concert with the neurotransmitter and neuropeptide systems to govern brain function. The chemokine system can thus be thought of as the third major transmitter system in the brain.     

Are proteasomes involved in the formation of the kinetochore?

Proteasomes catalyse the degradation of proteins responsible for the regulation of mitosis enabling the cell to complete cell division. We have studied the effect of an inhibitor of the chymotrypsin-like activity of the proteasome on the trilaminar structure of the kinetochore in HeLa cells. Whereas a role for the proteasome in the degeneration of the kinetochore was predicted, we found instead that the inhibitor strongly retarded kinetochore development. We observed different developmental stages of the kinetochore from the fibrous ball of a prekinetochore to the mature kinetochore in one cell. The data presented here support the proposition that proteasomes are involved in kinetochore formation.accepted for publication by H. C. MacgregorDedicated to the memory of Prof. Dr. Daniel Mazia, a fatherly friend.     

Are there ethnic differences in deletions in the dystrophin gene?

We studied 160 cases of Duchenne muscular dystrophy (DMD) drawn from all parts of India, using multiplex PCR of 27 exons. Of these, 103 (64.4%) showed intragenic deletions. Most (69.7%) of the deletions involved exons 45–51. The phenotype of cases with deletion of single exons did not differ significantly from those with deletion of multiple exons. The distribution of deletions in studies from different countries was variable, but this was accounted for either by the small number of cases studied, or by fewer exons analyzed. It is concluded that there is likely to be no ethnic difference with respect to deletions in the DMD gene. Am. J. Med. Genet. 68:152–157, 1997 © 1997 Wiley-Liss, Inc.     

What are the indications in France for vaccination against Japanese encephalitis?

Japanese encephalitis is a mosquito-borne viral disease occurring in rural and rice-growing areas of Asia, where mosquitoes proliferate, transmitting the Flavivirus from viremic animals, mostly pigs, to humans. Japanese encephalitis has recently spread to previously non-affected regions, leading to serious outbreaks among non-immune populations. Although it has a high proportion of unsymptomatic infection, clinical encephalitis is usually severe, resulting in a very high mortality rate, and neurologic sequellae are common among survivors. Vaccines are used in several Asian countries. One of these vaccines is now available to French travellers, but only in international vaccination centres with an authorization from the French drug agency (Agence fran?aise de sécurité sanitaire des produits de santé). The aim of this paper is to clarify the recommendations for immunisation in each country of the affected regions. The area can be divided into three epidemiological zones, with tropical, subtropical and temperate characteristics. For the first two, vaccination is recommended before a long stay in a rural area, especially during the rainy season; in temperate climates, outbreaks occur in summer and autumn. However, local variations such as intensive rice-growing or development of pig breeding may interfere with these patterns. Long-term visitors should consult a local physician and prevention of mosquito bites is always recommended.     

What Are Those Complement Genes Doing in the MHC?

Since the recognition twelve years ago that the Ss/Slp proteins of the mouse [1, 2], which had been mapped inside the H-2 gene complex [3], are structurally [5-7] and functionally [8, 9] related to the fourth component of complement, the significance of this map location has remained a mystery. Evidence that the C4 structural genes are closely associated with the MHC in man [10], in the guinea pig [11], and in other species [12, 13], and that structural genes for complement factors C2 and Bf are also MHC-associated, in the mouse [14, 46, 47], in man [10], and in other species [12], has established that this is not a peculiarity of the murine H-2 complex.     

Are histological alterations observed in the gallbladder precancerous lesions?

INTRODUCTION

Gallbladder cancer, which is characterized by rapid progression and a poor prognosis, is a complex disease to treat. Unfortunately, little is known currently about its etiology or pathogenesis. A better understanding of its carcinogenesis and determining risk factors that lead to its development could help improve the available treatment options.

METHOD

Based on this better understanding, the histological alterations (such as acute cholecystitis, adenomyomatosis, xanthogranulomatous cholecystitis, polyps, pyloric metaplasia, intestinal metaplasia, dysplasia, cancer and others) in gallbladders from 1,689 patients who underwent laparoscopic cholecystectomy for cholecystolithiasis were analyzed. The association of these gallbladder histological alterations with clinical data was studied.

RESULTS

Gender analysis revealed a greater incidence of inflammatory changes in males, while dysplasia and cancer were only found in women. The incidence of cholesterolosis was greater in the patients 60 years of age and under, and the incidence of adenomyomatosis and gangrene was greater in the elderly patients. A progressive increase in the average age was observed as alterations progressed through pyloric metaplasia, intestinal metaplasia, dysplasia and then cancer, suggesting that the metaplasia-dysplasia-carcinoma sequence may occur in gallbladder cancer. Gallbladder histological alterations were also observed in asymptomatic patients.

CONCLUSION

The results of this study suggest that there could be an association between some histological alterations of gallbladder and cancer, and they also suggest that the metaplasia-dysplasia-carcinoma sequence could in fact be true in the case of gallbladder cancer. Nevertheless, further studies directed towards a perfect understanding of gallbladder carcinogenesis are required.     

Are non-pylori helicobacters present in the human oral cavity?

Introduction and objective

Helicobacter pylori (H. pylori) is a human gastric pathogen. Because of presence of H. pylori oral cavity, there is a possibility of H. pylori transmission by oral-oral route. In a crosssectional study, the presence of some virulence factors of H. pylori and also non-pylori Helicobacters in dental plaque samples of participants was investigated.

Methods

The samples were collected from at least two teeth surfaces. DNA of the samples was extracted using specific kit. The presence of dupA (jhp0917 and jhp0918) and babA2 genes and also Helicobacter genus and H. pylori species was investigated using polymerase chain reaction by specific primers.

Results

In total 44% (20/45) and 86.7% (39/45) of samples was positive for ureC and 16SrRNA genes respectively. The frequency of babA2, jhp0917 and jhp0918 genes in H. pylori isolates were 40, 20 and 65% respectively. It seems 19 samples were positive probably non-pylori Helicobacters.

Conclusion

In the present study we report for the first time the presence of non-pylori Helicobacter species and also high frequency of babA2 and dupA genotypes in dental plaque samples.

     

Are free radical reactions increased in the diabetic eye?

Reactive oxygen species (ROS) are thought to play a significant role in the development of diabetic retinopathy; however, no direct evidence supports ROS generation in vivo. This study used in vivo electron spin resonance (ESR) spectroscopy with a surface resonator to detect local free radical reactions. The ESR signal decay of carbamoyl-PROXYL was enhanced in the eyes of streptozotocin (STZ)-induced diabetic mice. This enhanced signal decay was suppressed by the administration of SOD or the pretreatment with aminoguanidine. We demonstrate, for the first time, specific free radical reactions in the eyes of mice with STZ-induced diabetes.     

Does processing of emotional facial expressions depend on intention? Time-resolved evidence from event-related brain potentials

We assessed the automaticity of emotional face processing with respect to the intentionality criterion, holding that automatic processes are triggered independently of intention. For this purpose, we observed emotion processing in event-related brain potential (ERP) components under five different task conditions. ERP components included the P1, N170, the early posterior negativity (EPN), and the late positive complex (LPC). Enhanced processing at perceptual stages as indicated by P1, N170, and EPN effects occurred independently of intention in angry expressions. In contrast, the emotion-related LPC, a putative manifestation of higher-level, more elaborative processing stages, depended on the intentional state of the participants. This suggests an automatic threat-related processing bias at perceptual stages, while higher cognitive emotion encoding is subject to voluntary control. Moreover, an independent component analyses (ICA) showed that EPN and LPC activity occurred simultaneously, indicating perceptual and higher cognitive emotion encoding to occur in parallel.     

Mutations in mtDNA: Are We Scraping the Bottom of the Barrel?

The small, maternally inherited mtDNA has turned out to be a Pandora's box of pathogenic mutations: 12 years into the era of "mitochondrial medicine," about 100 pathogenic point mutations and innumerable rearrangements have been associated with a bewildering variety of multisystemic as well as tissue-specific human diseases. After reviewing the principles of mitochondrial genetics, we compare and contrast the clinical and pathological features of disorders due to mutations in genes affecting mitochondrial protein synthesis with those of mutations in protein-coding genes. In contrast to the striking progress in our understanding of etiology, pathogenesis is only partially explained by the rules of mitochondrial genetics and remains largely terra incognita. We review recent progress in prenatal diagnosis and epidemiology. Therapy is still woefully inadequate, but a number of promising approaches are being developed.     

Eosinophilic angiocentric fibrosis and granuloma facial with extra facial presentation, the same pathology?

Eosinophilic angiocentric fibrosis is a rare fibro inflammatory lesion of unknown etiology which occurs usually in the upper respiratory tract mucosa of middle-aged adults. The histologic features show an eosinophilic vasculitis and an angiocentric fibrosis with onion-skin pattern. Firstly described as a mucosal variant of the granuloma facial, which is a rare cutaneous vasculitis with eosinophils, it is considerated by some authors as separated entities. Four cases have been described in the orbit and three of them were in fact an extension of a sinusal lesion. We report the first case affecting a 69-years-old male patient who showed an isolated orbital involvement in association with granuloma facial, extra facial. This observation illustrates the relationship between these two pathologies and consolidates the first hypothesis of a single disease with cutaneous or mucosal involvement.