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101.
102.
Previous studies have shown that following peripheral nerve injury there was a downregulation of the gap junction protein connexin 36 (Cx36) in the spinal cord; however, it is not known whether Cx36 protein is expressed in the dorsal root ganglia (DRGs), nor if its levels are altered following peripheral nerve injuries. Here we address these aspects in the adult rat lumbar DRG. Cx36 mRNA was detected using qRT-PCR, and Cx36 protein was identified in DRG sections using immunohistochemistry (IHC) and immunofluorescence (IF). Double staining revealed that Cx36 co-localizes with both anti-β-III tubulin, a neuronal marker, and anti-glutamine synthetase, a satellite glial cell (SGC) marker. In neurons, Cx36 staining was mostly uniform in somata and fibers of all sizes and its intensity increased at the cell membranes. This labeling pattern was in contrast with Cx36 IF dots mainly found at junctional membranes in islet beta cells used as a control tissue. Co-staining with anti-Cx43 and anti-Cx36 showed that whereas mostly uniform staining of Cx36 was found throughout neurons and SGCs, Cx43 IF puncta were localized to SGCs. Cx36 mRNA was expressed in normal lumbar DRG, and it was significantly down-regulated in L4 DRG of rats that underwent sciatic nerve injury resulting in persistent hypersensitivity. Collectively, these findings demonstrated that neurons and SGCs express Cx36 protein in normal DRG, and suggested that perturbation of Cx36 levels may contribute to chronic neuropathic pain resulting from a peripheral nerve injury.  相似文献   
103.
The enteric nervous system (ENS) is a network of neurons and glia found in the gut wall and governs this gastrointestinal function independently from the central nervous system (CNS). ENS comprises the myenteric plexus (MP) and the submucous plexus (SP). In this study, we examined the expression profile of neurofilament heavy chain (NF-H), neuron-specific enolase (NSE), calcyclin (S100A6), vimentin and glial fibril acidic protein (GFAP) in ovine ileal enteric neurons and enteric glia cells (EGCs) during prenatal development using an immunohistochemical method. The material of the study consisted of 15 different fetal ileum tissues obtained between days 60 and 150 of pregnancy. NF-H was observed in the majority of ganglion cells in SP and MP throughout the fetal period. It was determined that there was no NF-H reaction in some ganglion cells in Peyer’s patches of internal submucosal plexus (ISPF). In the early stage of pregnancy (60–90 days), there was no expression of NSE and S1006 in ileum. After this period, NSE and S1006 were expressed in the ganglion cells of the plexus, indicating an increase in the amount of expression towards the end of pregnancy. In the early period, vimentin expression was only detected in intramuscular interstitial cells (ICs) (60–90 days), but later (90–150 days) it was also seen in the cells around the ganglion cells in the plexus. On days 60–90 of gestation, GFAP expression only occurred in MP, but in later stages, staining was also detected in SP. In the plexus, an immunoreactivity was present in EGCs forming a network around the ganglion cell. During the last period of gestation (120–150 days), the number of GFAP-positive plexus increased, with the majority of these stained cells being observed in MP. Interestingly, weak staining or reaction did not occur in ISPF, unlike other plexuses. In conclusion, this is the first study that demonstrated the expression of NF-H, vimentin, S100A6, NSE and glial fibril acidic protein (GFAP) in ovine ileal ENS in the prenatal period. In the last period of gestation (120–150 days), the expression profile of ENS was similar to that of adult animals. The expression of the used markers increased toward the end of pregnancy. Our results suggest that neurons and EGCs show heterogeneity, and GFAP and NF-H cannot be used as panenteric glial or panneuronal markers, respectively. We also demonstrated, for the first time, the prenatal expression of S100A6 in enteric neurons and the possibility of using this protein for the identification of enteric neurons.  相似文献   
104.

Background

Salivary gland maturation and function are modulated by the nervous system. Nevertheless, little is known about salivary gland innervation during development, particularly minor salivary glands. This study investigated the development of the innervation of the palatine glands of rat.

Materials and methods

Frozen sections of rat palatine glands at different stages were immunohistochemically labeled for detection of the general nerve markers protein gene product 9.5 (PGP 9.5) and growth associated protein 43 (GAP-43), and the autonomic nerve markers calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY).

Results

PGP 9.5 and GAP-43-immunoreactive fibers (IRF) were present in the mesenchyme and in association with developing acini, ducts and blood vessels. GAP-43-IRF were more abundant and diffuse than PGP 9.5-IRF at early stages, but showed similar distribution with growth, ramifying out from thick bundles in connective tissues until encircling the secretory units observed around postnatal day 21 (PN21). CGRP-IRF were detected in the mesenchyme at embryonic day 20 (E20) and PN0. CGRP-IRF became numerous around PN7 and PN10. They then decreased to the adult level at PN21, mainly located around ducts and infrequently blood vessels. NPY-IRF were sparsely detected in the mesenchyme at E20, then detected in close proximity to acini in addition to blood vessels at PN3. NPY-IRF increased till reaching the adult stage, and were mainly associated with blood vessels and around mucous cells and some serous demilunes.

Conclusion

The findings indicated a developmental modification of the sensory and autonomic innervation which may play a role in the functional maturation of the palatine salivary glands.  相似文献   
105.
106.
A geographical stratification of Killer Immunoglobulin-like Receptors (KIR) has been reported worldwide. We first analyzed the distribution of 15 KIR genes in a sample of 50 East-Sicilians (ES). We used a Principal Component Analysis (PCA) to compare the KIR genetic content among ES and 10 modern populations who are descendants of the ancient invaders of Sicily: Spanish, French, Norwegians, Swedes, Finns, Tunisians, Moroccans, Arabs, Greeks, Turks. We also included a sample of Sardinians, and Senegalese (as outlier group). Then, we also compared the HLA-A, HLA-B and HLA-C allelic frequencies among ES and the same populations investigated for KIR. As to HLA-A and HLA-B polymorphisms, ES are close to Greek population who invaded the island for long time until 827 CE; while HLA-C and KIR distribution in ES are close to Spanish population that invaded Sicily (and Sardinia) starting from 1283. As to KIR, ES are close to Spanish and Sardinians. The immunogenetic fingerprint of ES may be the finely balanced result of the invasions that overwhelmed Sicily over the centuries.  相似文献   
107.
108.
109.

BACKGROUND:

Henry Norman Bethune is one of the most exciting and incredible surgeons that Canada has ever produced. Indeed, he is often characterized as one of the world’s best-known surgeons. He was an innovator and his scientific contributions have stood the test of time. In Canada, he will forever be remembered as a social activist committed to the welfare of the poor and to the reform of the health care system. In the People’s Republic of China, he is idolized and remains the only foreigner to ever become a national hero.

OBJECTIVE:

To detail the numerous and significant achievements of Henry Norman Bethune in the field of thoracic surgery and as a social activist and describe his heroic war-time actions on the battlefields of both Spain and China.

METHOD:

Information was gathered through the reading of the numerous publications written about the life and work of Bethune, interviews with knowledgeable people from Canadian and Chinese universities, analysis of Bethune’s own publications, and extensive experience of one of the authors in China.

RESULTS:

In the social sense, Henry Norman Bethune had a difficult personality, but he was deeply caring about the plight of his patients, especially the poor. As a thoracic surgeon, he could be ingenious, thoughtful and effective but he could also be abrasive, restless and temperamental. His scientific contributions were sound and, at the time, gained worldwide attention. As an activist, he led a crusade to reform the Canadian health care system, demanding free health care for all. His outstanding work during the Spanish Civil War, where he organized the first ever mobile blood transfusion unit, and during the Sino-Japanese war, where he was totally committed to the welfare of both soldiers and civilian population, were deliberate acts of resistance against Fascist onslaught and enthusiasm for the Communist cause.

CONCLUSIONS:

Henry Norman Bethune was unconventional and a revolutionary, but he was brilliant. He will forever be remembered as an innovative thoracic surgeon and outstanding humanitarian.  相似文献   
110.

Objective

To assess the prevalence of pain in the musculoskeletal system and possible reasons for these complaints among early age children from Warsaw schools.

Material and methods

The study was conducted in 34 randomly selected primary schools in Warsaw in 2011. 2748 survey-questionnaires were given to parents or legal guardians by children. Of these, 1509 surveys were subject to a final analysis. The survey included 66 questions regarding, among other things, pain in the musculoskeletal system in children. Additionally, there were questions about possibly occurring diseases, any postural defects, significant obesity, as well as effects of these complaints on the child''s physical activity. Survey data regarded 6–7-year-old children.

Results

In the group of 1509 respondents, 242 children (16%) complained about pain in the musculoskeletal system. Pain was located most frequently in the knee joints, and more rarely in the spine and joints in the upper extremities. In the group of children who complained about pain, moderate physical activity was statistically significantly limited. According to parents, physicians did not diagnose any medical conditions in 106 children. Joint disease was diagnosed in 33 children. Postural defects were diagnosed in 589 children. In 123 children complaining about pain at least one postural defect was diagnosed. Such defects were diagnosed statistically significantly more rarely (p = 0.011) in 1234 children who did not complain about pain (460 children). Platypodia or other foot deformation was observed in 25% of these children, spinal curvature in 12%, abnormal knee joint position in 11% and uneven hip position in 2% children. Of note, 17% of all children were significantly overweight. In overweight children the prevalence of pain, especially in the knee joints and feet, was significantly higher.

Conclusions

This study aims to underline the problem of musculoskeletal pain in early-age children which limits their physical activity. Also the authors draw attention to the issue of postural defects in a large group of school children. This issue undoubtedly requires more attention and a plan how to create more effective methods of prevention.  相似文献   
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