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991.
Concussive brain injury (CBI) accounts for approximately 75% of all brain-injured people in the United States each year and is particularly prevalent in contact sports. Concussion is the mildest form of diffuse traumatic brain injury (TBI) and results in transient cognitive dysfunction, the neuropathologic basis for which is traumatic axonal injury (TAI). To evaluate the structural and functional changes associated with concussion-induced cognitive deficits, adult mice were subjected to an impact on the intact skull over the midline suture that resulted in a brief apneic period and loss of the righting reflex. Closed head injury also resulted in an increase in the wet weight:dry weight ratio in the cortex suggestive of edema in the first 24 h, and the appearance of Fluoro-Jade-B-labeled degenerating neurons in the cortex and dentate gyrus of the hippocampus within the first 3 days post-injury. Compared to sham-injured mice, brain-injured mice exhibited significant deficits in spatial acquisition and working memory as measured using the Morris water maze over the first 3 days (p<0.001), but not after the fourth day post-injury. At 1 and 3 days post-injury, intra-axonal accumulation of amyloid precursor protein in the corpus callosum and cingulum was accompanied by neurofilament dephosphorylation, impaired transport of Fluoro-Gold and synaptophysin, and deficits in axonal conductance. Importantly, deficits in retrograde transport and in action potential of myelinated axons continued to be observed until 14 days post-injury, at which time axonal degeneration was apparent. These data suggest that despite recovery from acute cognitive deficits, concussive brain trauma leads to axonal degeneration and a sustained perturbation of axonal function.  相似文献   
992.
The COVID‐19 pandemic has had a significant impact on many aspects of head and neck cancer (HNC) care. The uncertainty and stress resulting from these changes has led many patients and caregivers to turn to HNC advocacy groups for guidance and support. Here we outline some of the issues being faced by patients with HNC during the current crisis and provide examples of programs being developed by advocacy groups to address them. We also highlight the increased utilization of these organizations that has been observed as well as some of the challenges being faced by these not‐for‐profit groups as they work to serve the head and neck community.  相似文献   
993.
Mammographic calcification is an important radiologic feature of early breast carcinoma whose index of suspicion for malignancy may be reported by a five‐tier R‐category system. This study aims to describe the histologic diagnoses underlying screen‐detected mammographic calcifications using both digital and screen‐film mammography, and to correlate these findings with radiologic R‐categories. Patients attending the Merrion Breast Screening Unit in Dublin between 2000 and 2011 were identified, who underwent needle‐core biopsy for assessment of mammographic calcifications without associated mass or architectural distortion. Radiologic R‐category was correlated with biopsy and excision histology reports. A total of 776 cases of calcification were identified, involving 769 individual patients. The radiologic R‐categories were as follows: R3 513 (66.1%), R4 192 (24.7%), R5 71 (9.1%). The positive predictive values for malignancy were R3 32.6%, R4 69.8%, R5 95.8%. Several histologic features of DCIS were associated with R5 rather than R3 radiology: high nuclear grade, solid or cribriform architecture, necrosis, periductal inflammation or fibrosis, and associated microinvasive or invasive carcinoma. Mammographic lesions and histologic whole and invasive tumors increased in size from R3 to R5. Radiologic size of calcifications correlated with whole (but not invasive) tumor size, although it tended to underestimate it by several millimeters. Digital‐detected calcifications were more likely than screen‐film detected to be categorized as R3 and less likely R4 or R5, and there was no significant difference in positive predictive value between the two imaging techniques in any R‐category. In conclusion, histologic features of DCIS, in particular those associated with high grade, are associated with R5 radiology. There is no significant difference in positive predictive value for malignancy in any R‐category between digital and screen‐film mammography.  相似文献   
994.
Peripheral neuropathy and insensate limbs and digits cause significant morbidity in diabetic individuals. Previous studies showed that deletion of the receptor for advanced end-glycation products (RAGE) in mice was protective in long-term diabetic neuropathy. Here, we tested the hypothesis that RAGE suppresses effective axonal regeneration in superimposed acute peripheral nerve injury attributable to tissue-damaging inflammatory responses. We report that deletion of RAGE, particularly in diabetic mice, resulted in significantly higher myelinated fiber densities and conduction velocities consequent to acute sciatic nerve crush compared with wild-type control animals. Consistent with key roles for RAGE-dependent inflammation, reconstitution of diabetic wild-type mice with RAGE-null versus wild-type bone marrow resulted in significantly improved axonal regeneration and restoration of function. Diabetic RAGE-null mice displayed higher numbers of invading macrophages in the nerve segments postcrush compared with wild-type animals, and these macrophages in diabetic RAGE-null mice displayed greater M2 polarization. In vitro, treatment of wild-type bone marrow–derived macrophages with advanced glycation end products (AGEs), which accumulate in diabetic nerve tissue, increased M1 and decreased M2 gene expression in a RAGE-dependent manner. Blockade of RAGE may be beneficial in the acute complications of diabetic neuropathy, at least in part, via upregulation of regeneration signals.Diabetes leads to the development of multiple complications (13). Peripheral neuropathy affects 30–50% of all diabetic patients (46). Individuals with diabetes are more vulnerable to superimposed thermal and pressure injuries (710). Diabetic individuals exposed to either topical application of capsaicin or intracutaneous excision axotomy (punch skin biopsy) displayed a reduction in regenerative rate, even without evidence of neuropathy, and reduced axonal regenerative sprouting and blood vessel growth, respectively, compared with nondiabetic control subjects (11,12). Studies of diabetic animals reported a delay of axonal regeneration after acute sciatic nerve crush compared with nondiabetic mice (13). Evidence suggests that enhanced accumulation of advanced glycation end products (AGEs) may be an important contributing mechanism to the pathogenesis of diabetes complications (14,15). AGEs are a heterogeneous group of molecules that impact cellular properties and gene expression via specific receptors such as receptor for advanced end-glycation product (RAGE) (1618). RAGE, a pattern recognition receptor, also interacts with multiple members of the proinflammatory S100/calgranulin family and with high-mobility group box 1 protein (HMGB1); both classes of molecules are implicated in inflammation and cellular migration (19,20). These non-AGE ligands may be released by dying cells, and evidence suggests that although RAGE is not intimately involved in innate immune responses, its upregulation and activation by these ligands contribute to sustained inflammation and suppression of repair (21,22).These considerations prompted us to hypothesize that RAGE action in superimposed acute injury to the peripheral nerve, particularly in diabetes, attenuates neurite outgrowth and axonal regeneration via tissue-damaging inflammatory mechanisms. We subjected wild-type (WT) and homozygous RAGE-null mice to acute sciatic nerve crush to dissect the specific contribution of bone marrow RAGE expression. We also subjected WT mice to lethal irradiation and performed reconstitution with bone marrow expressing or devoid of RAGE.  相似文献   
995.

Objectives:

To assess the effectiveness of appendectomy in women undergoing laparoscopy for chronic pelvic pain without identifiable pathology.

Methods:

This retrospective cohort study included women aged 15 to 50 years who underwent laparoscopic surgery for chronic pelvic pain without identifiable pathology. The cohort was divided into 2 groups: women who underwent appendectomy and women who had not undergone appendectomy at laparoscopic surgery. Postoperative pain was assessed at 6-week follow-up and by subsequent mailed questionnaire.

Results:

Women who underwent appendectomy (n = 19) were significantly more likely to report improvement in pain at 6-week follow-up than women who did not undergo appendectomy (n = 76) (93% vs 16%; P < .001). Thirty-six patients (38%) responded to the questionnaire at a median of 4.2 years after surgery, when the median change (improvement) in reported pain was greater in the appendectomy group than in the nonappendectomy group.

Conclusion:

Appendectomy is effective therapy for patients with chronic pelvic pain of unknown etiology who are undergoing laparoscopy.  相似文献   
996.
Following its introduction into Georgia in 2007, African swine fever virus (ASFV) has become widespread on the European continent and in Asia. In many cases, the exact route of introduction into domestic pig herds cannot be determined, but most introductions are attributed to indirect virus transmission. In this review, we describe knowledge gained about different matrices that may allow introduction of the virus into pig herds. These matrices include uncooked pig meat, processed pig‐derived products, feed, matrices contaminated with the virus and blood‐feeding invertebrates. Knowledge gaps still exist, and both field studies and laboratory research are needed to enhance understanding of the risks for ASFV introductions, especially via virus‐contaminated materials, including bedding and feed, and via blood‐feeding, flying insects. Knowledge obtained from such studies can be applied to epidemiological risk assessments for the different transmission routes. Such assessments can be utilized to help predict the most effective biosecurity and control strategies.  相似文献   
997.
998.

Background

Postmastectomy radiotherapy (PMRT) is well established in patients with ≥4 positive axillary lymph nodes (ALN); indications in 1 to 3 positive ALN remains controversial. We examined clinicopathologic criteria used for PMRT selection and compared locoregional recurrence (LRR), recurrence-free survival (RFS), and overall survival (OS) among patients with and without PMRT.

Methods

Between 1995 and 2006, a total of 1,331 patients with T1–T2 tumors and 1 to 3 positive ALN underwent mastectomy. We excluded T3/T4 tumors and neoadjuvant chemotherapy; we analyzed 1,087 patients (924 without PMRT, 163 with PMRT). Chi square testing compared clinicopathologic features between groups. The Kaplan–Meier method and Cox regression analysis examined the association between PMRT and LRR, RFS, and OS.

Results

PMRT patients were more likely to be ≤50 years old (p = 0.001) and to have larger tumors (p = 0.01), disease of a higher histologic grade (p = 0.03), lymphovascular invasion (LVI) (p < 0.0001), a greater number of positive ALN (p < 0.0001), extranodal invasion (p < 0.0001), and macroscopic ALN metastases (p < 0.0001). With a median follow-up of 7 years, PMRT and no-PMRT groups were similar in LRR (p = 0.57), RFS (p = 0.70), and OS (p = 0.28). On multivariate analysis of the no-PMRT group, age ≤50 years (p = 0.002) and presence of LVI (p < 0.0001) were associated with LRR. Stratified by age and LVI, patients ≤50 years old and with LVI had the highest 5-year LRR, 10.1 versus 1.1 %, than in patients >50 years old without LVI (p < 0.001).

Conclusions

By using clinicopathologic features, clinicians delivered PMRT to a select group of patients with T1–T2 tumors and 1 to 3 positive ALN, resulting in similarly low rates of 5-year LRR. Among patients not receiving PMRT, age ≤50 years and LVI were associated with increased LRR rates and warrant PMRT consideration.  相似文献   
999.
BACKGROUND: The accelerated incidence of colorectal carcinoma in individuals with inflammatory bowel disease suggests that cellular perturbation triggered by chronic inflammation is linked to the development of dysplasia and neoplastic transformation. To test the mechanistic links between these processes, we employed the following murine strains: (1) multiple intestinal neoplasia (Min) +/- mice, bearing a mutation in the adenomatous polyposis coli (APC) gene; (2) mice deficient in interleukin 10 (IL-10), which normally develop enterocolitis; and (3) Min +/-/IL-10 null mice, first developed in our laboratory. METHODS: Mice with either parental strain or the cross were sacrificed at time points ranging from 10 to 30 weeks of age. The small bowel and colon of 170 IL-10 null mice, 31 Min +/- mice, and 120 Min +/-/IL-10 null mice were examined microscopically. RESULTS: The number of flat adenomas was increased in the colons of the Min +/-/IL-10-/- mice, compared with the Min +/- mice (P = .0005). Neither colitis-type dysplasia nor carcinoma was increased in the Min +/-/IL-10 -/-, compared with the IL-10 null mice (P = .18). Mice deficient in IL-10 developed colitic-type dysplasia (P = .0001) or carcinoma (P = .0001) correlated with increasing inflammation. CONCLUSIONS: Breeding the Min +/- genotype into the IL-10 -/- background increased the incidence of colonic adenomas. Our studies demonstrate that acceleration of dysplasia and progression to invasion were associated with the degree of the inflammatory response in mice deficient in IL-10. These findings provide a novel system to dissect the pathways by which inflammatory mechanisms accelerate adenoma formation.  相似文献   
1000.
OBJECTIVE: Abdominal aortic aneurysms often coexist with reduced lung function and chronic obstructive pulmonary disease (COPD). These conditions are each associated with cigarette smoking, cardiovascular disease, and evidence of increased inflammatory and hemostatic activity. The aim of this study was to determine if these factors accounted for the link between aneurysms and pulmonary disease. METHODS: The design was a case-control study comparing patients with an asymptomatic abdominal aortic aneurysm with population-based controls without an aneurysm. Aneurysms were diagnosed by ultrasound scan, and pulmonary function was measured by respiratory questionnaire and spirometry. Activation of inflammation and hemostasis was measured by assay of plasma interleukin-6 (IL-6), fibrinogen, von Willebrand factor (vWF), tissue plasminogen activator (tPA) antigen, fibrin D-dimer, and plasmin antiplasmin complexes. RESULTS: Cases with an abdominal aortic aneurysm (n = 89) had more COPD and worse expiratory lung function as measured by forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) than controls (n = 98) (FEV1, 1.9 vs 2.2 L, P < .01; FEV1/FVC, 0.67 vs 0.75, P < .001) and did not differ in restrictive function (FVC, 2.9 vs 3.0 L, P = .33). Cases also had higher levels of lifetime cigarette smoking (30 vs 24 pack-years, P < 0.01), cardiovascular disease (35% vs 18%, P = .01), plasma fibrinogen (3.5 vs 3.1 g/L, P = .02), IL-6 (2.8 vs 1.8, pg/mL, P < .001), plasmin antiplasmin complexes (596 vs 384 microg/L, P = .01), and D-dimer (442 vs 93 ng/mL, P < .001). On multiple logistic regression analysis of lung function and COPD on the risk of aneurysm, both cigarette smoking and cardiovascular disease had little effect on the relationships. For the markers of activated inflammation and hemostasis, plasmin antiplasmin complexes and D-dimer had the most important confounding effect on the odds ratios. All markers combined had a substantial effect: odds ratio of aneurysm for a one standard deviation decrease in FEV1 fell from 2.3 (95% confidence interval [CI], 1.5 to 3.5) (P < .01) to 1.3 (95% CI, 0.55 to 2.4) (P > or = .05). CONCLUSION: The association between reduced respiratory function and abdominal aortic aneurysm was not accounted for by cigarette smoking or cardiovascular disease. We hypothesize that activation of inflammation and hemostasis in response to injury may be an important explanation of the association between aneurysm formation and reduced respiratory function. Further studies are required to test this hypothesis.  相似文献   
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