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991.
Carotid occlusions are associated with de novo intracranial aneurysm formation in clinical case reports, but this phenomenon is not widely studied. We performed bilateral carotid ligation (n=9) in rabbits to simulate carotid occlusion, and sham surgery (n=3) for control. Upon euthanasia (n=3 at 5 days, n=6 at 6 months post ligation, and n=3 at 5 days after sham operation), vascular corrosion casts of the circle of Willis (CoW) were created. Using scanning electron microscopy, we quantified gross morphologic, macroscopic, and microscopic changes on the endocasts and compared findings with histologic data. At 5 days, CoW arteries of ligated animals increased caliber. The posterior communicating artery (PCom) increased length and tortuosity, and the ophthalmic artery (OA) origin presented preaneurysmal bulges. At 6 months, calibers were unchanged from 5 days, PComs further increased tortuosity while presenting segmental dilations, and the OA origin and basilar terminus presented preaneurysmal bulges. This exploratory study provides evidence that flow increase after carotid occlusion produces both compensatory arterial augmentation and pathologic remodeling such as tortuosity and saccular/fusiform aneurysm. Our findings may have considerable clinical implications, as these lesser-known consequences should be considered when managing patients with carotid artery disease or choosing carotid ligation as a therapeutic option.  相似文献   
992.
Sporadic Creutzfeldt–Jakob disease (sCJD) generally manifests itself by cognitive or rapidly progressive motor symptoms. An atypical onset or an unusual evolution may delay the diagnosis. Among patients with a confirmed diagnosis of sCJD following a post-mortem neuropathological examination at the Neuropathology Centre of Lille, France, those who had presented with atypical cognitive disorders at onset were included in the study. Four patients were included. The first patient (64-years-old) presented early language disorders, later accompanied by apathy and behavioral disorders. The prolonged course suggested a diagnosis of progressive primary aphasia. The second patient (68-years-old) presented with aphasia, apraxia, and ataxia of the right upper limb with parkinsonian syndrome, suggesting corticobasal degeneration. In the two last patients (58- and 61-years-old), the onset was marked by an anxiety–depression syndrome, falls, visual hallucinations, extra-pyramidal syndrome, and fluctuating cognitive decline. The diagnosis raised was probable Lewy body dementia. The 14.3.3 protein was found in two of the four cases. The clinical elements found may initially suggest focal atrophy or Lewy body dementia. A very rapid clinical deterioration generally suggests sCJD, but in the last case, the evolution was particularly slow. The diagnosis of sCJD must be considered in cases of rapid-onset dementia, even if all of the clinical criteria are not present. The detection of the 14.3.3 protein and multifold increase in total-Tau with normal or slightly increased phosphorylated-Tau in the CSF are additional arguments to reinforce the diagnosis. The post-mortem neuropathological examination is important to confirm the diagnosis.  相似文献   
993.
Glutamate transporters (excitatory amino-acid transporters (EAATs)) are essential for brain homeostasis. While previous studies indicate that the vascular endothelium contributes to glutamate efflux in the adult brain, little information is available regarding glutamate uptake in the immature brain. The present study shows a differential expression pattern of EAATs between cortical microvessels in adults and newborns. In addition, adult cortical endothelial cells take up glutamate more efficiently than neonatal cells. Our findings indicate age-specific changes in extracellular glutamate regulation by brain endothelial cells, suggesting differences in the efficiency of glutamate efflux during an excitotoxic process that, in turn, may contribute to age-specific brain vulnerability.  相似文献   
994.
We present a rare complication of abdominal liposuction: bowel perforation and necrotizing fasciitis. Because of bilateral lumbar hernia, a 56-year-old woman had caecum and descending colon perforation during lipoplasty. She had septic shock syndrome at her admission. The authors treated this complex wound with several debridement, omental flap, NPWT and split-thickness skin graft. The incidence of abdominal wall perforation with visceral injury is 14 in 100,000 liposuctions performed. There are only 12 cases of bowel perforation in literature but this complication is probably underestimated. Prompt surgical debridement is absolutely mandatory in this life threatening scenario. Lumbar hernia is very rare and should be ruled out before every abdominal liposuction clinically or with imaging modalities.KEY WORDS: Bowel perforation, liposuction, lumbar hernia, necrotizing fasciitis, negative pressure large wound therapy  相似文献   
995.

Background

Bilateral laparoscopic adrenalectomy (BLA) is an effective therapy for the management of persistent hypercortisolism in patients after failed transphenoidal pituitary tumor resection for Cushing’s disease. Extracortical adrenal tissue has been identified as a source of persistent hypercortisolism and, if not resected along with both adrenal glands, may lead to treatment failure. We report a reliable and reproducible technique called the “psoas sign” for BLA in patients with Cushing’s disease which reduces the likelihood of retained extra-adrenal cortical rests and may reduce intraoperative complications.

Methods

A 16-year retrospective review of all consecutive patients who underwent transabdominal BLA at a single tertiary care center was performed. All patients underwent BLA utilizing the psoas sign technique and all procedures were performed replicating these predetermined surgical steps: (1) Identification of the inferior pole of the gland. (2) Identification of the inferior aspect of the adreno-caval groove on the right or the adrenal vein/renal vein confluence on the left. (3) Division of the adrenal vein. (4) Dissection and removal of the adrenal gland with clearance of all retroperitoneal fat overlying the psoas muscle.

Results

Between October 1996 and December 2012, 92 patients underwent BLA for refractory Cushing’s disease. Patients were predominantly female (90 %) with a median age of 40 years (17–71). There were 3 intraoperative complications (3.2 %), 2 conversions (2.2 %), and 1 death (1.09 %). Four patients were identified as having extracortical rests of adrenal tissue within the retroperitoneal fat (4.3 %). Mean operative time was 272 min (±79.25, n = 68) and median estimated blood loss was 50 mL (10–800 mL).

Conclusions

The psoas sign technique provides a clear view of the adrenal fossa and facilitates careful dissection of the anatomic planes around the adrenal gland. This technique is feasible, reproducible and in our experience allows for safe removal of both adrenal glands and all surrounding extracortical adrenal tissue.  相似文献   
996.

Background

C3 glomerulopathy (C3G) is characterized by predominant C3 deposits in glomeruli and dysregulation of the alternative pathway of complement. Half of C3G patients have a C3 nephritic factor (C3NeF). C3G incorporated entities with a range of features on microscopy including dense deposit diseases (DDD) and C3 glomerulonephritis (C3GN). The aim of this work was to study children cases of C3G associated with C3NeF.

Methods

We reviewed 18 cases of C3G with a childhood onset associated with C3NeF without identified mutations in CFH, CFI, and MCP genes.

Results

Clinical histories started with recurrent hematuria for seven patients, nephrotic syndrome for four, acute post-infectious glomerulonephritis for three and acute renal failure for four. Twelve patients had a low C3 at first investigation. Kidney biopsy showed ten C3GN and eight DDD. Twenty-three percent of the patients tested presented elevated sC5b9. Seven patients relapsed 3 to 6 years after the onset. At the end of follow-up, two patients were under dialysis, 11 had a persistent proteinuria, five had none; four patients did not follow any treatment. Steroids were first used in 80 % of cases.

Conclusions

C3NeF associated C3G has a heterogeneous presentation and outcome. Anti-proteinuric agents may control the disease during follow-up, even after nephrotic syndrome at the onset. The efficiency of immunosuppressive therapy remains questionable.  相似文献   
997.
Calciphylaxis [calcific uraemic arteriolopathy (CUA)] is a rare disease at the interface of nephrology, dermatology and cardiology. CUA most often occurs in adult dialysis patients. It is only rarely seen in patients without relevant chronic kidney disease, and only anecdotal reports about childhood calciphylaxis have been published. Clinically, CUA is characterized by a typical cascade, starting with severe pain in initially often inconspicuous skin areas, followed by progressive cutaneous lesions that may develop into deep tissue ulcerations. The typical picture is a mixture of large retiform ulceration with thick eschar surrounded by violaceous, indurated, tender plaques. The histopathological picture reveals arteriolar, often circumferential, calcification and extensive matrix remodelling of the subcutis. These findings explain the macroscopic correlation between skin induration and ulceration. The prognosis in CUA patients is limited due to underlying comorbidities such as uraemic cardiovascular disease and infectious complications. The etiology of CUA is multifactorial, and imbalances between pro- and anti-calcification factors, especially in the setting of end-stage renal disease play an outstanding role. Oral anticoagulant treatment with vitamin K antagonists is a predominant CUA trigger factor. It is speculative as to why children and adolescents only develop calciphylaxis in exceptional cases, although a seldom usage of vitamin K antagonists and the preserved mineral buffering capacity of the growing skeleton may be protective.  相似文献   
998.
Human volunteers were vaccinated with experimental Neisseria meningitidis serogroup B vaccines based on strain H44/76 detoxified L3 lipooligosaccharide (LOS)-derived outer membrane vesicles (OMV) or the licensed Cuban vaccine, VA-MENGOC-BC. Some volunteers were able to elicit cross-bactericidal antibodies against heterologous L2-LOS strain (760676). An immuno-proteomic approach was used to identify potential targets of these cross-bactericidal antibodies using an L2-LOS derived OMV preparation. A total of nine immuno-reactive spots were detected in this proteome: individuals vaccinated with the detoxified OMVs showed an increase in post-vaccination serum reactivity with Spots 2–8, but not with Spots 1 and 9. Vaccination with VA-MENGOC-BC induced sera that showed increased reactivity with all of the protein spots. Vaccinees showed increases in serum bactericidal activity (SBA) against the heterologous L2-LOS expressing strain 760676, which correlated, in general, with immunoblot reactivity. The identities of proteins within the immuno-reactive spots were determined. These included not only well-studied antigens such as Rmp, Opa, PorB and FbpA (NMB0634), but also identified novel antigens such as exopolyphosphatase (NMB1467) and γ-glutamyltranspeptidase (NMB1057) enzymes and a putative cell binding factor (NMB0345) protein. Investigating the biological properties of such novel antigens may provide candidates for the development of second generation meningococcal vaccines.  相似文献   
999.
1000.
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