[Analysis of clinicopathological and molecular abnormalities of angioimmunoblastic T-cell lymphoma].

OBJECTIVE: To analyze the clinicopathological features, molecular changes and prognostic factors in angioimmunoblastic T-cell lymphoma (AITL). METHODS: Sixty-one cases AITL diagnosed by Department of Pathology of Peking University Cancer Hospital were collected with their clinical data. Morphologically, they were classified as typeⅠ[lymphoid tissue reactive hyperplasia (LRH) like]; typeⅡ[marginal zone lymphoma(MZL)like] and type Ⅲ [peripheral T-cell lymphoma, not specified (PTCL-NOS) like]. Immunohistochemical staining was used to evaluate the presence of follicular helper T-cell (TFH) phenotype, proliferation of extra germinal center (GC) follicular dendritic cells (FDCs), presence of Hodgkin and Reed-Sternberg (HRS)-like cells and large B transformation. The density of Epstein-Barr virus (EBV) + cells was counted with slides stained by Epstein-Barr virus encoded RNA (EBER) in situ hybridization on high power field (HPF). T-cell receptor / immunoglobulin gene (TCR/IG) clonality and targeted exome sequencing (TES) test were performed when necessary. SPSS 22.0 software was used for statistical analysis. RESULTS: Morphological subtype (%): 11.4% (7/61) cases were classified as type Ⅰ; 50.8% (31/61) as type Ⅱ; 37.8% (23/61) as type Ⅲ. 83.6% (51/61) cases showed classical TFH immunophenotype. With variable extra-GC FDC meshwork proliferation (median 20.0%); 23.0% (14/61) had HRS-like cells; 11.5% (7/61) with large B transformation. 42.6% (26/61) of cases with high counts of EBV. 57.9% (11/19) TCR+/IG-, 26.3% (5/19) TCR+/IG+, 10.5% (2/19) were TCR－/IG－, and 5.3% (1/19) TCR－/IG+. Mutation frequencies by TES were 66.7% (20/30) for RHOA, 23.3% (7/30) for IDH2 mutation, 80.0% (24/30) for TET2 mutation, and 33.3% (10/30) DNMT3A mutation. Integrated analysis divided into four groups: (1) IDH2 and RHOA co-mutation group (7 cases): 6 cases were type Ⅱ, 1 case was type Ⅲ; all with typical TFH phenotype; HRS-like cells and large B transformation were not found; (2) RHOA single mutation group (13 cases): 1 case was type Ⅰ, 6 cases were type Ⅱ, 6 cases were type Ⅲ; 5 cases without typical TFH phenotype; 6 cases had HRS-like cells, and 2 cases with large B transformation. Atypically, 1 case showed TCR－/IG－, 1 case with TCR－/IG+, and 1 case with TCR+/IG+; (3) TET2 and/or DNMT3A mutation alone group (7 cases): 3 cases were type Ⅱ, 4 cases were type Ⅲ, all cases were found with typical TFH phenotype; 2 cases had HRS-like cells, 2 cases with large B transformation, and atypically; (4) non-mutation group (3 cases), all were type Ⅱ, with typical TFH phenotype, with significant extra-GC FDC proliferation, without HRS-like cells and large B transformation. Atypically, 1 case was TCR－/IG－. Univariate analysis confirmed that higher density of EBV positive cell was independent adverse prognostic factors for both overall survival (OS) and progression free survival(PFS), (P=0.017 and P=0.046). CONCLUSION: Pathological diagnoses of ALTL cases with HRS-like cells, large B transformation or type Ⅰ are difficult. Although TCR/IG gene rearrangement test is helpful but still with limitation. TES involving RHOA, IDH2, TET2, DNMT3A can robustly assist in the differential diagnosis of those difficult cases. Higher density of EBV positive cells counts in tumor tissue might be an indicator for poor survival.

[Clinicopathological features and prognosis of anorectal melanoma: A report of 68 cases].

OBJECTIVE: To investigate the clinicopathological characteristics of anorectal mucosal melanoma (ARMM), and to evaluate the prognostic factors. METHODS: A total of 68 primary ARMM surgical specimens from 2010 to 2018 were retrospectively studied. Slides were reviewed to evaluate pathological features. Slingluff staging method was used for staging. RESULTS: (1) Clinical features: The median age at diagnosis in this group was 61.5 years, with a male-to-female ratio 1 ∶1.62. The most common complaint was blooding (49 cases). For anatomic site, anorectum was the prevalent (66.2%), followed by rectum (20.6%). At the time of diagnosis, 28 cases were stage Ⅰ (localized stage, 41.2%), 25 cases were stage Ⅱ (regional lymph node metastasis, 36.8%), and 15 cases were stage Ⅲ (distant metastasis, 22.1%). Five patients underwent wide local excision, the rest abdominoperineal resection, and 48 patients received adjuvant therapy after surgery. (2) Pathological features: Grossly 88.2% of the tumors were exophytic polypoid masses, with the median tumor size 3.5 cm and the median tumor thickness 1.25 cm. Depth of invasion below lamina muscularis mucosae ranged from 0-5.00 cm (median 1.00 cm). The deepest site of tumor invasion reached muscular layer in 27 cases, and perirectal tissue in 16 cases. Melanin pigmentation was absent or not obvious in 67.6% of the cases. The predominant cytology was epithelioid (45 cases, 66.2%). The rate for ulceration, necrosis, lymphovascular invasion, and perineural invasion was 89.7%, 35.3%, 55.9%, and 30.9%, respectively. The median mitotic count was 18/mm2. The positive rate of S100, HMB-45 and Melan-A were 92.0%, 92.6% and 98.0%, respectively. The median of Ki-67 was 50%. The incidences of mutations within CKIT, BRAF and NRAS genes were 17.0% (9 cases), 3.8% (2 cases) and 9.4% (5 cases), respectively. (3) Prognosis: Survival data were available in 66 patients, with a median follow-up of 17 months and a median survival time of 17.4 months. The 1-year, 2-year and 5-year overall survival rate was 76.8%, 36.8% and 17.2%, respectively. The rate of lymphatic metastasis at diagnosis was 56.3%. Forty-nine patients (84.5%) suffered from distant metastasis, and the most frequent metastatic site was liver. Univariate analysis revealed that tumor size (>3.5 cm), depth of invasion below lamina muscularis mucosae (>1.0 cm), necrosis, lymphovascular invasion, BRAF gene mutation, lack of adjuvant therapy after surgery, deep site of tumor invasion, and high stage at diagnosis were all poor prognostic factors for overall survival. Multivariate model showed that lymphovascular invasion and BRAF gene mutation were independent risk factors for lower overall survival, and high stage at diagnosis showed borderline negative correlation with overall survival. CONCLUSION: The overall prognosis of ARMM is poor, and lymphovascular invasion and BRAF gene mutation are independent factors of poor prognosis. Slingluff staging suggests prognosis effectively, and detailed assessment of pathological features, clear staging and genetic testing should be carried out when possible. Depth of invasion below lamina muscularis mucosae of the tumor might be a better prognostic indicator than tumor thickness.

[Analysis of gadolinium magnetic resonance in inner ear by tympanic membrane puncture in 1 126 cases].

Objective: To investigate the success rate, safety and repeatability of gadolinium (Gd)-enhanced inner ear magnetic resonance (MR) by tympanic membrane puncture. Methods: The imaging and clinical data of 1 126 cases with Gd-enhanced inner ear MR by tympanic membrane puncture from February 2010 to June 2020 were retrospectively analyzed. All cases were reexamined in the outpatient clinic after MR gadolinium contrast to check the tympanic membrane and external auditory canal. The success rate was identified by whether there was gadolinium contrast in the labyrinth. Meanwhile, the pure tone hearing threshold data of asymptomatic ears before and after gadolinium contrast was collected and compared. The consistency in the scores of the asymptomatic ears in patients who underwent twice Gd-enhanced MR was analyzed, in which the scores of vestibular, cochlea, and semicircular canals were acquired respectively. Results: Among 1 126 patients [including 506 males and 620 females, aged (54±17) years old], 45 were reviewed once, while 4 patients were reviewed twice. There were 958 cases who were examined on both sides, and 168 cases were checked only on one side. There were 166 cases of Meniere's disease (14.7%), 219 cases of sudden sensorineural hearing loss (19.5%) and 741 cases of being remained to be investigated (65.8%), respectively. A total of 2 084 ears underwent first gadolinium angiography, of which 63 ears had no contrast agent in the labyrinth, with a success rate of 97.0% (2 021/2 084). Only 1 case had tympanic membrane perforation while the rest had no complications. The hearing threshold before and after otography in 57 asymptomatic ears had no differences at any frequency (all P>0.05). Moreover, the consistency in the scores of two radiography within the 21 asymptomatic ears in vestibular and cochlea was good [both intraclass correlation coefficient (ICC) values>0.75]. Conclusion: The success rate and safety of Gd-enhanced inner ear MR is high by tympanic membrane puncture, and the results can be repeated well.

Genetic investigation of nodal melanocytic nevi in cases of giant congenital melanocytic nevus.

Nodal melanocytic nevi are common incidental findings in lymph nodes that have been removed during sentinel lymph node biopsy for melanoma. They can also occur in the local lymph nodes of the giant congenital nevus (GCN), but very little is known regarding nodal melanocytic nevi in the giant congenital nevus, especially at the genetic level. There are two theories that explain the possible pathogenesis of nodal melanocytic nevi, mechanical transport and arrested migration during embryogenesis. However, there have been few tests of these two theories at the molecular biology level until now. We used whole-exon sequencing to test these two theories at the gene level for the first time. In clonal evolution analysis of patient 1, whose tumor mutation burden (TMB) value was relatively stable, showed that the GCN and nodal nevus had the same initial origin and then diverged into two branches as a result of gene mutations. In contrast, analysis indicated that in the other patient, whose TMB value declined from 68.02/Mb in a GCN to 17.55/Mb in associated nodal nevi, these two samples were from different origins at the beginning, each with its own gene mutation. These results are consistent with the two respective theories at the molecular biological level. We provided the first tests of the two theories of pathogenesis of nodal melanocytic nevi at the gene level, and these findings may provide some clues for further study. In addition, not all nodal nevi should be treated as lymph node metastasis in clinical diagnosis, and we should make a comprehensive assessment and judgment of nodal melanocytic nevi based on morphology, immunological characteristics and fluorescence in situ hybridization (FISH) tests.

[Genetic changes and biological potential of proliferative nodule in congenital pigmented nevus].

Objective: To study the genetic changes and biological potential of proliferative nodule in congenital melanocytic nevus. Methods: Whole-exome sequencing was carried out using the technique of next-generation sequencing (NGS) in order to detect the genomic alterations of two cases of proliferative nodules (PN) in congenital melanocytic nevi (CMN). Twelve cases of CMN and ten cases of malignant melanoma were used as benign and malignant controls, respectively. Mutated genes that possessed statistically significant difference between benign and malignant controls were listed, according to what benign and malignant statuses were classified and clustered. The heatmaps of clustering analyses were depicted using heatmap package. Fluorescence in situ hybridization (FISH) was also used to validate the above results. Results: Eighty-six common somatic gene mutations were detected in two samples of PN. Compared with CMN, PN had 52 more mutated genes. Furthermore, 22 of these 52 mutated genes were also detected in malignant melanoma samples. Two cases of PN fell between benign CMN and malignant melanoma in germline mutation clustering. Both cases of PN were positive in the FISH tests. Conclusions: The genetic changes of PN partially overlap with those of CMN and malignant melanoma. Therefore, although most of the PN manifest as a benign lesion clinically, it may have certain malignant potential at the genetic level, and warrant long-term monitoring and follow-up.

[A comparison between the revision of Atlanta classification and determinant-based classification in acute pancreatitis].

Objective: To compare the performance of the revision of Atlanta classification (RAC) and determinant-based classification (DBC) in acute pancreatitis. Methods: Consecutive patients with acute pancreatitis admitted to a single center from January 2001 to January 2015 were retrospectively analyzed. Patients were classified into mild, moderately severe and severe categories based on RAC and were simultaneously classified into mild, moderate, severe and critical grades according to DBC. Disease severity and clinical outcomes were compared between subgroups. The receiver operating curve (ROC) was used to compare the utility of RAC and DBC by calculating the area under curve (AUC). Results: Among 1 120 patients enrolled, organ failure occurred in 343 patients (30.6%) and infected necrosis in 74 patients(6.6%). A total of 63 patients (5.6%) died. Statistically significant difference of disease severity and outcomes was observed between all the subgroups in RAC and DBC (P<0.001). The category of critical acute pancreatitis (with both persistent organ failure and infected necrosis) had the most severe clinical course and the highest mortality (19/31, 61.3%). DBC had a larger AUC (0.73, 95%CI 0.69-0.78) than RAC (0.68, 95%CI 0.65-0.73) in classifying ICU admissions (P=0.031), but both were similar in predicting mortality(P=0.372) and prolonged ICU stay (P=0.266). Conclusions: DBC and RAC perform comparably well in categorizing patients with acute pancreatitis regarding disease severity and clinical outcome. DBC is slightly better than RAC in predicting prolonged hospital stay. Persistent organ failure and infected necrosis are risk factors for poor prognosis and presence of both is associated with the most dismal outcome.

Chronic stress and Rosiglitazone increase indices of vascular stiffness in male rats.

Prolonged and/or frequent exposure to psychological stress responses may lead to deterioration of organs and tissues, predisposing to disease. In agreement with this, chronic psychosocial stress is linked to greater cardiovascular risk, including increased incidence of atherosclerosis, myocardial ischemia, coronary heart disease, and death. Thus the association between stress and cardiovascular dysfunction represents an important node for therapeutic intervention in cardiovascular disease. Here we report that 2weeks of chronic variable stress (CVS) increased indices of vascular stiffness, including increased collagen deposition in the aortic adventitia and increased resting pulse pressure, in male rats. Thus CVS may represent a useful rodent model for stress-associated CVD, especially for aging populations for which widening pulse pressure is a well-known risk factor. Additionally, we report that the thiazolidinedione Rosiglitazone (RSG) blunts chronic stress-associated increases in circulating corticosterone. Despite this, RSG was not protective against adverse cardiovascular outcomes associated with chronic stress. Rather RSG itself is associated with increased pulse pressure, and this is exacerbated by chronic stress-highlighting that chronic stress may represent an additional contributor to RSG-associated cardiovascular risk.

[Expression of epidermal growth factor receptor mutation specific antibodies in lung adenocarcinoma: evaluation of sensitivity, specificity and relationship to histologic subtypes].

OBJECTIVE: To evaluate the expression of epidermal growth factor receptor (EGFR) mutation specific antibodies in invasive lung adenocarcinomas, and their sensitivity, specificity, as well as relationship to histological subtypes. METHODS: Immunostaining with EGFR mutation-specific antibodies, del E746-A750 in exon 19 and L858R in exon 21, was performed in tissue microarrays of 884 cases of resection specimens to study the relationship between the immunophenotypes and morphologic subtypes. The sensitivity and specificity of the stains were compared with gene mutations detected by amplified refractory mutation system-polymerase chain reaction (ARMS-PCR). RESULTS: Of the 884 cases, the expression of del E746-A750 in exon 19 was 3+ , 2+ , 1+ and 0 in 7 cases (0.79%), 38 cases (4.30%), 129 cases (14.59%) and 710 cases (80.32%), respectively. For L858R in exon 21, 3+ , 2+ , 1+ and 0 staining were seen in 82 cases (9.28%), 93 cases (10.52%), 82 cases (9.28%) and 627 cases (70.93%), respectively. For both antibodies, positive expression (1+ or more) was mainly observed in lepidic, acinar and papillary predominant subtypes, and rarely seen in solid subtype or invasive mucinous adenocarcinoma (P=0.014 and 0.016). If 1+ to 3+ expression was set as positive, the specificity of exon 19/exon 21 reached 98.59%/92.98%, while the sensitivity was relatively lower (62.86%/88.89%). If 2+ to 3+ expression was read as positive, the specificity and sensitivity were 99.30%/97.37% and 25.71%/74.60% for exon 19/exon 21. If only 3+ expression was considered positive, the specificity was 100.0% for both antibodies, with a low sensitivity (8.57% for exon 19 and 34.92% for exon 21). Of the 18 cases with E746-A750 del in exon 19 based on molecular detection, the sensitivity of immunohistochemistry for exon 19 was 88.89% if a positive cutoff value ≥1+ was used; in contrast, of the 8 cases harboring other deletions in exon 19, only two cases were positive as 1+ . CONCLUSIONS: Both the EGFR mutation specific antibodies del E746-A750 in exon 19 and L858R in exon 21 demonstrate high specificity and relatively low sensitivity, and are mostly expressed in lepidic, acinar and papillary predominant subtypes, but rarely in solid subtype or invasive mucinous adenocarcinoma. For cases with 3+ expression, a mutational statue for EGFR is likely. For the 2+ positive cases, the accuracy to predict mutation almost reaches 90%, but molecular detection for confirmation is desirable. For the 1+ and negative cases, DNA-based test is essential to avoid false negativity.

[Expression of CD137 in tumor cells of Hodgkin lymphoma from Northern China and its application in pathological differential diagnosis].

OBJECTIVE: To investigate the expression of CD137 in HRS cells of classical Hodgkin Lymphoma (cHL), and its application in the pathological differential diagnosis. METHODS: 54 cases of cHL with "HRS" cells, and 55 cases of non-cHL with "HRS-like" cells as control group were collected. "HRS" cells and "HRS-like" cells rich areas in slides were selected from relevant groups to produce two tissue microarrays. This study focused solely on "HRS" cells and "HRS-like" cells, immunohistochemical staining for antibodies including CD30, CD15, CD20, CD3, and PAX5 were performed on CHL cases, CD137 (clone BBK-2) immunostaining and EBER in situ hybridization were detected in both groups. RESULTS: All cHL cases aged 22.0-68.0 (median 45.5) years with the male to female ratio as about 1.7∶1 primarily involved lymph nodes; while in the control group, 54 cases aged 12.0-81.0 (median 50.0) years with male∶female=1.9∶1 primarily located in nodes with only 1 case in skin. In the cHL group, CD30, CD15, CD20 and CD3 were positive in 100.0%, 70.4%, 18.5% and 0 cases in order, and PAX5 showed weak to moderate positive in 70.4% cases; the positive rate of EBER was 25.9% in cHL group, and 21.8% in the control group; The CD137 positive rates were 57.4% in cHL and 14.5% in the control groups with a significant difference (P<0.001). There were no significant differences when CD137 expressions were further compared according to the differences in age [elder group (aged 60) /non elderly group], gender (male/female), EBV infection (yes/no), histological subtype and the expression of those major diagnostic markers (positive/negative) in either cHL or control groups (all P valued>0.05). The positive rates of CD137 expression in cHL were significantly different when sub-grouped according to accession year before or after 2013 (39.4% vs 85.7%, P=0.001); However, no difference was seen in the control group (12.5% vs 16.1% , P=0.705). For those cases after 2013, the CD137 positive ratio of cHL group was more significantly different with the control one (85.7% vs 16.1%, P<0.001). CONCLUSION: Frequent expression of CD137 in "HRS" cells of cHL cases from Northern China could be detected by IHC method, while the CD137 expression was much lower in "HRS-like" cells of the control group. The positive rate of CD137 expression by immunohistochemical staining significantly increased in this cohort stored less than 3 years, which might be more reliable. CD137 might be potentially applied on pathological differential diagnosis of cHL.

[TNFAIP3 deletion status in classical Hodgkin lymphoma and its relation to Epstein-Barr virus].

Objective: To investigate the TNFAIP3/A20 abnormalities and its association with Epstein-Barr virus (EBV) in classical Hodgkin lymphoma (CHL). Methods: Formalin-fixed, paraffinembedded tissue blocks of 54 CHL patients were collected and subjected to the construction of tissue microarray (TMA) for further analyses. EBV status was evaluated by in situ hybridization (ISH) for EBER1/2 and immunohistochemistry (IHC) with anti-LMP-1 antibody. Fluorescence in situ hybridization (FISH) and IHC were performed to determine the copy number alterations of TNFAIP3 and A20 protein expression respectively. Results: The concordance rate of IHC for LMP-1 and ISH for EBER1/2 was100%, and 25.9% (14/54) cases were identified with EBV infection. Immunohistochemistry analysis demonstrated 27.8% (15/54) cases with A20 expression deficiency. Of the 54 cases tested for A20 expression, 49 cases were simultaneously analyzed by FISH, which showed 10 (20.4% ) cases harboring TNFAIP3 deletion. However, discrepancy was observed between the results of A20 by IHC and TNFAIP3 deletion by FISH. Only 1 case with TNFAIP3 deletion demonstrated complete loss of A20 immunoreactivity. In addition, comparison of the frequency of either A20 expression loss or TNFAIP3 deletion between EBV-positive and-negative cases did not reveal any significance (P>0.05). Conclusion: TNFAIP3 deletion could be observed in both EBV-positive and - negative CHL cases. A20 expression by IHC could not confirm TNFAIP3 deletion by FISH, which might be related to the technical issues.

Regulatory interactions of stress and reward on rat forebrain opioidergic and GABAergic circuitry.

Palatable food intake reduces stress responses, suggesting that individuals may consume such ?comfort? food as self-medication for stress relief. The mechanism by which palatable foods provide stress relief is not known, but likely lies at the intersection of forebrain reward and stress regulatory circuits. Forebrain opioidergic and gamma-aminobutyric acid ergic signaling is critical for both reward and stress regulation, suggesting that these systems are prime candidates for mediating stress relief by palatable foods. Thus, the present study (1) determines how palatable ?comfort? food alters stress-induced changes in the mRNA expression of inhibitory neurotransmitters in reward and stress neurocircuitry and (2) identifies candidate brain regions that may underlie comfort food-mediated stress reduction. We used a model of palatable ?snacking? in combination with a model of chronic variable stress followed by in situ hybridization to determine forebrain levels of pro-opioid and glutamic acid decarboxylase (GAD) mRNA. The data identify regions within the extended amygdala, striatum, and hypothalamus as potential regions for mediating hypothalamic-pituitary-adrenal axis buffering following palatable snacking. Specifically, palatable snacking alone decreased pro-enkephalin-A (ENK) mRNA expression in the anterior bed nucleus of the stria terminalis (BST) and the nucleus accumbens, and decreased GAD65 mRNA in the posterior BST. Chronic stress alone increased ENK mRNA in the hypothalamus, nucleus accumbens, amygdala, and hippocampus; increased dynorphin mRNA in the nucleus accumbens; increased GAD65 mRNA in the anterior hypothalamus and BST; and decreased GAD65 mRNA in the dorsal hypothalamus. Importantly, palatable food intake prevented stress-induced gene expression changes in subregions of the hypothalamus, BST, and nucleus accumbens. Overall, these data suggest that complex interactions exist between brain reward and stress pathways and that palatable snacking can mitigate many of the neurochemical alterations induced by chronic stress.

"Snacking" causes long term attenuation of HPA axis stress responses and enhancement of brain FosB/deltaFosB expression in rats.

A history of limited, intermittent intake of palatable food (sucrose drink) attenuates hypothalamic-pituitary-adrenal (HPA) axis stress responses and induces markers of neuronal plasticity in stress- and reward-regulatory brain regions. Synaptic plasticity could provide a mechanism for long-term changes in neuronal function, implying that sucrose stress-dampening may endure over long periods of time. The present study tests the persistence of HPA axis dampening and plasticity after cessation of palatable drinking. Adult, male Long-Evans rats (n=10-13) with free access to water and chow were given additional twice-daily access to 4ml sucrose (30%) or water for 14days. Rats were subsequently tested for HPA responsiveness to an acute (20min) restraint stress at 1, 6 and 21days after the cessation of sucrose. Brains were collected for immunohistochemical analysis of FosB/deltaFosB, a marker of long-term neuronal plasticity, in the basolateral amygdala (BLA) and nucleus accumbens (NuAc). Prior sucrose consumption significantly decreased the plasma corticosterone response to restraint at 1day after the last palatable drink presentation, and also increased FosB/deltaFosB-positive cells in the BLA and in the NuAc core. This HPA-dampening persisted through 21days after the termination of the palatable drink, as did the increased FosB/deltaFosB immunoreactivity in both the BLA and the NuAc core. These data suggest that chronic palatable food intake causes lasting changes in stress/reward-modulatory circuitry and that the suppressed hormonal response to stress that can persist well beyond periods of palatable drink exposure.

Assessment of capsular laxity in patients with recurrent anterior shoulder dislocation using MRI.

OBJECTIVE: The purpose of our study was to investigate the usefulness of MRI in assessing capsular laxity in patients with recurrent shoulder dislocation. MATERIALS AND METHODS: The records of 64 consecutive patients (the study group consisted of 58 patients, 45 male and 13 female; average age, 39.3 years; range, 13-82 years) who underwent MR arthrography between October 2002 and May 2008 were retrospectively reviewed. The patients were divided into three groups: group A, no shoulder dislocation; group B, first dislocation; and group C, recurrent dislocation. The maximum capsular widths at the anterior, anteroinferior, and inferior regions in the neutral and abducted and externally rotated (ABER) positions were measured on oblique sagittal images. The relationship of capsular width with the number of dislocations, type of capsular attachment, presence of anteroinferior labral tear, and patient sex were evaluated. The sensitivity and specificity of MRI and clinical tests in detecting capsular laxity were also calculated. RESULTS: Among all three patient groups, there were significant differences (p < 0.05) in the widths with the shoulder in the ABER position and the degree of capsular tightening at the anterior region. The average maximum width was largest in group C and smallest in group A. There was a significant difference in the degree of anterior capsular tightening in groups B and C. A moderate correlation of capsular width and anterior tightening (R = -0.45) with number of shoulder dislocations was found. There was a significant difference in capsular width and capsular tightening in relation to the presence of an anteroinferior labral tear. The sensitivity and specificity to detect capsular laxity were 92% and 100%, respectively, for clinical tests and 85% and 96% for MRI. CONCLUSION: MRI is a useful and objective method to assess capsular laxity in patients with recurrent shoulder dislocation.

Chronic stress produces enduring decreases in novel stress-evoked c-fos mRNA expression in discrete brain regions of the rat.

Chronic stress produces numerous adaptations within the hypothalamic-pituitary-adrenal (HPA) axis that persist well after cessation of chronic stress. We previously demonstrated profound attenuation of HPA axis responses to novel environment 4-7 days following chronic stress. The present study tests the hypothesis that this HPA axis hyporesponsivity is associated with reductions in stress-evoked c-fos mRNA expression, a marker of neuronal activation, in discrete brain regions. Adult male Sprague-Dawley rats underwent 1 week of chronic variable stress (CVS), with unhandled rats serving as controls. Independent groups of control and CVS rats were exposed to novel environment at 16 h, 4 days, 7 days, or 30 days after CVS. Marked reductions of c-fos mRNA expression in the CVS group persisted for at least 30 days within the paraventricular nucleus of the hypothalamus, and for at least 1 week in rostroventrolateral septum and lateral hypothalamus. Lower levels of c-fos mRNA expression were observed at 16 h recovery in the ventrolateral medial preoptic area, basolateral amygdala, anterior cingulate cortex, and prelimbic cortex. The results demonstrate long-term alterations in neuronal activation within neurocircuits critical for regulation of physiological and psychological responses to stressors.

Effects of weight bearing and non-weight bearing exercises on bone properties using calcaneal quantitative ultrasound.

OBJECTIVE: This study was designed to investigate bone properties using heel quantitative ultrasound (QUS) in young adults participating in various sports. METHODS: A cross sectional study was performed on Chinese male students (n = 55), aged 18-22 years. Subjects with previous fractures or suffering from any diseases known to affect bone metabolism or taking any medication with such an effect, were not included. The subjects were categorised according to their main sporting activities, including soccer (n = 15) (a high impact, weight bearing exercise), dancing (n = 10) (a low impact, weight bearing exercise), and swimming (n = 15) (non-weight bearing exercise). A sedentary group acted as controls (n = 15). A reproducibility study of the velocity of sound (VOS) and the broadband ultrasound attenuation (BUA) measurement was performed and analysed using the intraclass correlation coefficient (ICC). RESULTS: There was good intra-investigator and inter-investigator agreement (ICC > or = 0.8; p < 0.05) in the measurement of BUA and VOS. No significant differences in BUA and VOS (p > 0.05) were found between the dominant and non-dominant heel. Soccer players (137 +/- 4.3 dB/MHz; 1575 +/- 56 m/s; 544.1 +/- 48.4) and dancers (134.6 +/- 3.7 dB/MHz; 1538 +/- 46 m/s; 503.0 +/- 37.0) had significantly higher BUA, VOS, and stiffness index (SI) scores (p < 0.05), respectively, than swimmers (124.1 +/- 5.1 dB/MHz; 1495 +/- 42 m/s; 423.3 +/- 46.9) and the sedentary control group (119.9 +/- 6.1 dB/MHz; 1452 +/- 41 m/s; 369.9 +/- 46.4). A trend of a significant linear increase with the weight bearing and high impact exercise was revealed in all QUS parameters (p < 0.05). CONCLUSION: This cross sectional study indicated that regular participation in weight bearing exercise in young people might be beneficial for accruing peak bone mass and optimising bone structure.

Arcuate nucleus transcriptome profiling identifies ankyrin repeat and suppressor of cytokine signalling box-containing protein 4 as a gene regulated by fasting in central nervous system feeding circuits.

The arcuate nucleus of the hypothalamus is a primary site for sensing blood borne nutrients and hormonal messengers that reflect caloric status. To identify novel energy homeostatic genes, we examined RNA extracts from the microdissected arcuate nucleus of fed and 48-h fasted rats using oligonucleotide microarrays. The relative abundance of 118 mRNA transcripts was increased and 203 mRNA transcripts was decreased during fasting. One of the down-regulated mRNAs was ankyrin-repeat and suppressor of cytokine signalling box-containing protein 4 (Asb-4). The predicted structure of Asb-4 protein suggested that it might encode an intracellular regulatory protein, and therefore its mRNA expression was investigated further. Reverse transcription quantitative polymerase chain reaction was used to validate down-regulation of Asb-4 mRNA in the arcuate nucleus of the fasted Sprague-Dawley rat (relative expression of Asb-4 mRNA: fed = 4.66 +/- 0.26; fasted = 3.96 +/- 0.23; n = 4, P < 0.01). Down-regulation was also demonstrated in the obese fa/fa Zucker rat, another model of energy disequilibrium (relative expression of Asb-4 mRNA: lean Zucker = 3.91 +/- 0.32; fa/fa = 2.93 +/- 0.26; n = 5, P < 0.001). In situ hybridisation shows that Asb-4 mRNA is expressed in brain areas linked to energy homeostasis, including the arcuate nucleus, paraventricular nucleus, dorsomedial nucleus, lateral hypothalamus and posterodorsal medial amygdaloid area. Double in situ hybridisation revealed that Asb-4 mRNA colocalises with key energy homeostatic neurones. In the fed state, Asb-4 mRNA is expressed by 95.6% of pro-opiomelanocortin (POMC) neurones and 46.4% of neuropeptide Y (NPY) neurones. By contrast, in the fasted state, the percentage of POMC neurones expressing Asb-4 mRNA drops to 73.2% (P < 0.001). Moreover, the density of Asb-4 mRNA per fasted POMC neurone is markedly decreased. Conversely, expression of Asb-4 mRNA by NPY neurones in the fasted state is modestly increased to 52.7% (P < 0.05). Based on its differential expression, neuroanatomical distribution and colocalisation, we hypothesise that Asb-4 is a gene involved in energy homeostasis.

Regional differences in trabecular BMD and micro-architecture of weight-bearing bone under habitual gait loading--a pQCT and microCT study in human cadavers.

This study used both multi-slice pQCT and microCT to investigate regional changes in bone mineral density and structural parameters in the ultradistal tibia and in the mid-femoral neck under habitual gait loading. Twenty cadavers with 2 females and 18 males aged 70.8 +/- 8.5 were used in this study. Seventy-two cylindrical bone cores with 5 mm in diameter and 10 mm in length from the anterior/posterior and superior/inferior regions were obtained from ultradistal tibia and mid-femur neck, respectively, so that their differences in terms of volumetric trabecular bone mineral density (tBMD) as well as micro-architectural parameters could be studied. The results showed that the mean volumetric tBMD at both the organ (including the bone marrow spaces) and tissue levels (excluding the bone marrow spaces) were a 49.2% and 28.3%, respectively, lower in the anterior bone cores than in the posterior bone cores from the ultradistal tibia (P < 0.01). MicroCT measurements on BV/TV, BS/TV, Tb.N, Tb.Th, and DA were found to be on average of 33.5%, 23.6%, 9.1%, 18.0%, and 14.6%, respectively, lower in the anterior trabecular bone cores (P < 0.001), while Tb.Sp and SMI were 12.5% and 29.3%, respectively, higher in the anterior trabecular bone cores (P < 0.01). No significant difference in micro-architectural parameters was found in the trabecular bone cores obtained from mid-femoral neck, except that the mean DA of the inferior bone cores was significantly higher by 30.1% than that of the superior bone cores (P = 0.01). A statistically significant linear relationship with the correlation coefficient, ranging from 0.37 to 0.94 and -0.62 to -0.85, respectively, was shown between the tBMD at the organ level and all of the micro-architectural parameters (P < 0.05). We suggest that dynamic loading changes during the striking of the heel in normal gait, as well as the peaks of the hip joint reaction force occur during the heel strike and before toe off positions in the lifetime of the subject may account for such regional differences in BMD and micro-architecture. The findings from the correlation study also suggest that, apart from BMD, the micro-architecture may exhibit adaptation in response to such excessive loading.

Regional differences in cortical bone mineral density in the weight-bearing long bone shaft--a pQCT study.

This study used a multislice peripheral quantitative computed tomography (pQCT) to measure volumetric BMD (vBMD) and cortical thickness for investigating regional adaptation in lower tibial shaft in 72 healthy postmenopausal women aged 47-60. Tomographic slices were analysed on four distinct cortical regions: the anterior, posterior, medial and lateral cortical wall. One-way analysis of variance (ANOVA) test was used to compare the vBMD in the four regions. The results showed that the posterior cortex had the highest vBMD (1923 +/- 135.3 mg/cm(3)), significantly (P < 0.001) higher than the anterior cortex (1805 +/- 110.6 mg/cm(3)), medial cortex (1863 +/- 103.6 mg/cm(3)) and lateral cortex (1815 +/- 111.6 mg/cm(3)); whereas there was no significant difference (P > 0.05) between the medial and lateral cortices located near the neutral plane of bending. The anterior cortex had the greatest thickness (2.56 +/- 0.47 mm), significantly (P < 0.001) greater than that of the posterior cortex (2.11 +/- 0.27 mm), medial cortex (2.20 +/- 0.39 mm) and lateral cortex (2.03 +/- 0.29 mm). The vBMD of the posterior cortex was a significant 6.5% higher than that of the anterior cortex (P < 0.001); whereas the anterior cortical thickness was a significant 21.3% greater than that of the posterior cortex (P < 0.001). There was no linear relationship found between cortical vBMD and cortical thickness measured at the four cortical regions (r = 0.086, P > 0.05). In conclusion, the regional differences, with higher vBMD found in posterior cortex, might be a result of mechanical adaptation, which caused the posterior cortex to sustain higher compressive loading than the anterior tensile cortex during the landing phase in the gait cycles of individuals. Nevertheless, regional geometric adaptation in anterior cortical thickness might be adapted to accommodate for the reduced vBMD and to reduce the bending stress in this region.