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1.
Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed.  相似文献   
2.
Legg-Calvé-Perthes disease (LCPD) is a juvenile form of ischemic femoral head osteonecrosis, which produces chronic hip synovitis, permanent femoral head deformity, and premature osteoarthritis. Currently, there is no medical therapy for LCPD. Interleukin-6 (IL-6) is significantly elevated in the synovial fluid of patients with LCPD. We hypothesize that IL-6 elevation promotes chronic hip synovitis and impairs bone healing after ischemic osteonecrosis. We set out to test if anti-IL-6 therapy using tocilizumab can decrease hip synovitis and improve bone healing in the piglet model of LCPD. Fourteen piglets were surgically induced with ischemic osteonecrosis and assigned to two groups: the no treatment group (n = 7) and the tocilizumab group (15 to 20 mg/kg, biweekly intravenous injection, n = 7). All animals were euthanized 8 weeks after the induction of osteonecrosis. Hip synovium and femoral heads were assessed for hip synovitis and bone healing using histology, micro-CT, and histomorphometry. The mean hip synovitis score and the number of synovial macrophages and vessels were significantly lower in the tocilizumab group compared with the no treatment group (p < .0001, p = .01, and p < .01, respectively). Micro-CT analysis of the femoral heads showed a significantly higher bone volume in the tocilizumab group compared with the no treatment group (p = .02). The histologic assessment revealed a significantly lower number of osteoclasts per bone surface (p < .001) in the tocilizumab group compared with the no treatment group. Moreover, fluorochrome labeling showed a significantly higher percent of mineralizing bone surface (p < .01), bone formation rate per bone surface (p < .01), and mineral apposition rate (p = .04) in the tocilizumab group. Taken together, tocilizumab therapy decreased hip synovitis and osteoclastic bone resorption and increased new bone formation after ischemic osteonecrosis. This study provides preclinical evidence that tocilizumab decreases synovitis and improves bone healing in a large animal model of LCPD. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
3.
Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging.  相似文献   
4.
Background and Aims It is a commonly held notion that patients with cirrhosis do not suffer from deep vein thrombosis (DVT) or pulmonary embolism (PE) because they are naturally anticoagulated. However, to date, no studies have been carried out that objectively address this issue. We conducted a study to examine the relationship between cirrhosis and DVT/PE events. Methods A case–control study of patients seen at a tertiary care hospital was performed. Cases were hospitalized patients with biopsy and/or imaging plus clinical evidence of cirrhosis. Well-matched patients with no known evidence of cirrhosis served as controls. The DVT/PE events were identified by the international classification of disease-9 (ICD-9) codes and confirmed with radiographic/nuclear imaging. The Charlson Index was calculated to determine the comorbidity. The incidence of DVT/PE in cirrhotic patients was also compared to patients with chronic kidney disease (CKD), congestive heart failure (CHF), and solid organ cancers. Results This study consisted of 963 cirrhotics and 12,405 controls. Both the incidence of DVT/PE (1.8 vs. 0.9%, P = 0.007) and Charlson Index scores (3.2 ± 1.8 vs. 0.9 ± 1.5, P < 0.001) were higher in cirrhotics than in the controls. However, in the multivariate analysis, the presence of cirrhosis was not associated with DVT/PE [odds ratio (OR) 0.87, P = 0.06]. Partial thromboplastin time (PTT; OR 0.88, P = 0.04) and serum albumin (OR 0.47, P = 0.03) were the independent predictors of DVT/PE. The incidence of DVT/PE in cirrhotics (1.8%) was lower than that in patients with other medical illnesses: 7.1% in CKD, 7.8% in CHF, and 6.1% in cancers. Conclusion Patients with cirrhosis do not have a lower risk of DVT/PE than non-cirrhotic controls without other significant co-morbidities, such as CHF, CKD, and solid organ cancers. Partial thromboplastin time and serum albumin were found to be independently predictive of DVT/PE in cirrhotic patients.  相似文献   
5.
OBJECTIVE: Existing literature indicates that the mortality rate with each variceal bleeding episode is 30-50%. Over the past 2 decades, there have been significant developments in the management of variceal bleeding. The effect of these developments on the natural history of variceal bleeding is unclear. Therefore, a retrospective, multicenter study was conducted to define the outcomes of variceal bleeding and to describe the patterns of current practice in the management of variceal bleeding. METHODS: All patients with documented variceal bleeding hospitalized at four large county hospitals from January 1, 1997, to June 30, 2000, were included. Study outcomes were in-hospital, 6-wk, and overall mortality, rate of rebleeding, transfusion requirement, and length of stay. After discharge, patients were followed until death or study closure date, on June 30, 2000. RESULTS: A total of 231 subjects were included, and their in-hospital, 6-wk, and overall mortality rates were 14.2%, 17.5%, and 33.5%, respectively. The frequency of rebleeding during follow-up was 29%. Median length of total hospital stay was 8 days (0-34 days). Median number of packed red cell units transfused was 4 U (0-60 U). Upper endoscopy was performed in 95% of patients within 24 h, and endoscopic therapy was done in all but eight patients (ligation 64%, sclerotherapy 33%). Octreotide was administered in 74% of the patients. Portasystemic shunts were performed in 7.5% of the patients for controlling acute variceal bleeding. CONCLUSIONS: The mortality rate after variceal bleeding in this study was substantially lower than previously reported. This suggests that advances made in the management of variceal bleeding have improved outcomes after variceal bleeding.  相似文献   
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Legg‐Calvé‐Perthes disease (LCPD) is a childhood hip disorder of ischemic osteonecrosis of the femoral head. Hip joint synovitis is a common feature of LCPD, but the nature and pathophysiology of the synovitis remain unknown. The purpose of this study was to determine the chronicity of the synovitis and the inflammatory cytokines present in the synovial fluid at an active stage of LCPD. Serial MRI was performed on 28 patients. T2‐weighted and gadolinium‐enhanced MR images were used to assess synovial effusion and synovial enhancement (hyperemia) over time. A multiple‐cytokine assay was used to determine the levels of 27 inflammatory cytokines and related factors present in the synovial fluid from 13 patients. MRI analysis showed fold increases of 5.0 ± 3.3 and 3.1 ± 2.1 in the synovial fluid volume in the affected hip compared to the unaffected hip at the initial and the last follow‐up MRI, respectively. The mean duration between the initial and the last MRI was 17.7 ± 8.3 months. The volume of enhanced synovium on the contrast MRI was increased 16.5 ± 8.5 fold and 6.3 ± 5.6 fold in the affected hip compared to the unaffected hip at the initial MRI and the last follow‐up MRI, respectively. In the synovial fluid of the affected hips, IL‐6 protein levels were significantly increased (LCPD: 509 ± 519 pg/mL, non‐LCPD: 19 ± 22 pg/mL; p = 0.0005) on the multi‐cytokine assay. Interestingly, IL‐1β and TNF‐α levels were not elevated. In the active stage of LCPD, chronic hip synovitis and significant elevation of IL‐6 are produced in the synovial fluid. Further studies are warranted to investigate the role of IL‐6 on the pathophysiology of synovitis in LCPD and how it affects bone healing. © 2015 American Society for Bone and Mineral Research  相似文献   
10.

Background

Preeclampsia increases the risk of heart disease. Defects in the protease corin, including the variant T555I/Q568P found in approximately 12% of blacks, have been associated with preeclampsia and cardiac hypertrophy. The objective of this study was to investigate the role of corin and the T555I/Q568P variant in preeclampsia-associated cardiac alterations using genetically modified mouse models.

Methods

Virgin wild-type (WT) and corin knockout mice with or without a cardiac WT corin or T555I/Q568P variant transgene were mated at 3 or 6 months of age. Age- and genotype-matched virgin mice were used as controls. Cardiac morphology and function were assessed at gestational day 18.5 or 28 days postpartum by histologic and echocardiographic analyses.

Results

Pregnant corin knockout mice at gestational day 18.5 developed cardiac hypertrophy. Such a pregnancy-associated phenotype was not found in WT or corin knockout mice with a cardiac WT corin transgene. Pregnant corin knockout mice with a cardiac T555I/Q568P variant transgene developed cardiac hypertrophy similar to that in pregnant corin knockout mice. The cardiac hypertrophy persisted postpartum in corin knockout mice and was worse if the mice were mated at 6 instead of 3 months of age. There was no hypertrophy-associated decrease in cardiac function in pregnant corin knockout mice.

Conclusions

In mice, corin deficiency causes cardiac hypertrophy during pregnancy. Replacement of cardiac WT corin, but not the T555I/Q568P variant found in blacks, rescues this phenotype, indicating a local antihypertrophic function of corin in the heart. Corin deficiency may represent an underlying mechanism in preeclampsia-associated cardiomyopathies.  相似文献   
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