Diffusely invasive supratentorial rosette-forming glioneuronal tumor: illustrative case

BACKGROUND

Rosette-forming glioneuronal tumors (RGNTs) are rare tumors composed of mixed glial and neurocytic components. Most lesions are confined to the posterior fossa, especially in the region of the fourth ventricle, in young adults. In few instances, diffuse involvement of the supratentorial region is identified, thereby creating significant challenges in diagnosis, surgical intervention, and prognostication.

OBSERVATIONS

The authors present a 23-year-old female with chronic headaches, papilledema, and hydrocephalus who underwent radiographic evaluation revealing obstructive hydrocephalus and diffuse supratentorial enhancing and nonenhancing cystic and nodular lesions. The patient underwent a right frontal craniotomy and septostomy. An exophytic nonenhancing right frontal horn lesion was resected, and an enhancing third-ventricular lesion was biopsied. Final pathology of both of the lesions sampled was consistent with RGNT. Next-generation sequencing demonstrated tumor alterations in the FGFR-1 and PIK3CA genes. Targeted therapy with the FGFR inhibitor erdafitinib demonstrated a partial remission.

LESSONS

Diffuse supratentorial spread of RGNT is an extremely rare presentation of an already uncommon pathology. In some cases, gross-total resection may not be feasible. Goals of surgery include acquiring tissue for diagnosis, maximizing safe resection, and treating any associated hydrocephalus. FGFR inhibitors may be of benefit in cases of disease progression.

Endovascular Mechanical Thrombectomy for Right Hemispheric Stroke Syndrome Due to Acute Left A1-A2 Junction Thromboembolic Occlusion

Background: Endovascular mechanical thrombectomy (EVT) for large vessel occlusions has had a dramatic impact on the management of acute ischemic stroke. Extended use of EVT beyond American Heart Association guidelines has been successful in carefully selected cases. Case Report: A 71-year-old male presented to our comprehensive stroke center upon awakening with mild left hemiparesis. He was found to have a chronic occlusion of the right supraclinoid segment of the internal carotid artery. Angiography demonstrated large vessel occlusion of the contralateral A1-A2 junction that was successfully recanalized. Imaging at 24 hours displayed no evidence of infarct, the patient rapidly improved during hospitalization, and he was discharged on postoperative day 7 with a National Institutes of Health Stroke Scale score of zero. Conclusion: We describe successful EVT of a patient presenting with false-localizing symptoms consistent with a right hemispheric acute ischemic stroke secondary to left A1-A2 junction large vessel occlusion. This case demonstrates the importance of a high index of suspicion when evaluating atypical stroke presentations and the effectiveness of EVT in the treatment of distal small-caliber vessels.

Vertebral artery dissection and associated ruptured intracranial pseudoaneurysm successfully treated with coil assisted flow diversion: A case report and review of the literature

Dissecting intracranial pseudoaneurysms (IPs) are associated with a high incidence of rupture and poor neurologic outcomes. Lesions in the posterior circulation are particularly malignant and pose even greater management challenges. Traditional management consists of microsurgical vessel sacrifice with or without bypass. Flow diversion (FD) in the setting of subarachnoid hemorrhage (SAH) represents a reconstructive treatment option and can be paired with coil embolization to promote more rapid thrombosis of the lesion. We report a case of a ruptured dissecting vertebral artery (VA) IP successfully acutely treated with coil-assisted FD. A 53-year-old male presented with a right V4 dissection spanning the origin of the posterior inferior cerebellar artery and associated ruptured V4 IP. The patient was treated with coil-assisted FD. Oral dual-antiplatelet therapy (DAPT) was initiated during the procedure, and intravenous tirofiban was used as a bridging agent. Immediate obliteration of the IP was achieved, with near-complete resolution of the dissection within 48 h. The patient made a complete recovery, and angiography at 6 weeks confirmed total IP obliteration, reconstruction of the VA, and a patent stent. The use of FD and DAPT in the setting of acute SAH remains controversial. We believe that coil-assisted FD in carefully selected patients offers significant advantages over traditional microsurgical and endovascular options. The risks posed by DAPT and potential for delayed thrombosis with FD can be effectively mitigated with planning and the development of protocols. We discuss the current literature in the context of our case and review the challenges associated with treating these often devastating lesions.

Detethering the superficial temporal artery: Application to tension free superficial temporal artery-middle cerebral artery bypasses

Extracranial-intracranial bypass has been shown to be effective in the surgical treatment of moyamoya disease, complex aneurysms, and tumors that involve proximal vasculature in carefully selected patients. Branches of the superficial temporal artery (STA) are used commonly for the bypass surgery; however, an appropriate length of the donor vessel must be harvested to avoid failure secondary to anastomotic tension. The goal of this cadaveric study was to investigate quantitatively operative techniques that can increase the STA length available to facilitate tension-free STA-middle cerebral artery (MCA) bypass. We conducted a cadaveric study using a total of 16 sides in eight cadavers. Measurements of the STA trunk with its frontal branch (STAfb) were taken before and after skeletonization and detethering of the STA with the STAfb and mobilization of the parietal branch of the STA. A final measurement of the STA with the STAfb was taken for the free length gained toward visible proximal cortical branches of the MCA. Paired student's t-tests were used to compare the mean length before and after mobilization and unpaired t-tests to analyze according to laterality. The mean length of the STA with the STAfb was 9.0 cm prior to modification. After skeletonization and mobilization, the mean lengths increased significantly to 10.5 and 11.3 cm, respectively (p < 0.05). Especially in the cases that had the coiled and tortuous STA, skeletonization was considerably effective to increase the length of the STA with the STAfb. After simulating a bypass by bringing the STAfb to the recipient MCA site, the mean extended length of the STA with the STAfb was 3.0 cm. There were no statistically significant differences between sides in all measurements. We report a significant increase in the mean STA length available (3.0 cm) following skeletonization and mobilization. Clinical applications of the extended length of the STA with the STAfb may facilitate tension-free STA-MCA bypasses and improve outcomes. Further studies are needed in a clinical context.

Middle Fossa Encephaloceles Treated via the Transmastoid Approach: A Case Series and Review of the Literature

BACKGROUND

Middle fossa (MF) encephaloceles are rare lesions resulting from herniation through defects in the tegmen tympani or mastoideum. Underlying etiologies and clinical presentations are variable. Surgical goals include fistula obliteration, resection of nonfunctioning parenchyma, and dehiscence repair. The middle cranial fossa approach (MCFA), transmastoid approach (TMA), and combined (MCFA + TMA) approaches have been described. The minimally invasive TMA provides excellent exposure of the pathology and allows for ample working room to repair the defect.

OBJECTIVE

We present short-term follow-up results in patients treated via the TM repair at our institution.

METHODS

A retrospective review of patients with symptomatic encephaloceles treated via the TMA by our multidisciplinary team. Patient demographics, clinical presentations, intraoperative findings, repair technique, and outcomes were highlighted.

RESULTS

A total of 16 encephaloceles in 13 patients were treated. Defect etiologies included spontaneous (50.0%), secondary to chronic infection (25.0%), or cholesteatoma (18.8%). Defects were most often within the tegmen mastoideum (68.8%). Average length of surgery was 3.3 h (95% CI: 2.86-3.67) and length of stay 3.9 d (95% CI: 3.09-4.79). On short-term follow-up (average 11.5 mo), no patients experienced postoperative cerebrospinal fluid leak or recurrence. The majority of patients (83.3%) experienced confirmed improvement or stabilization of hearing.

CONCLUSION

MF encephaloceles present with various clinical manifestations and result from multiple underlying etiologies. The TMA is an alternative to craniotomy and our short-term results suggest that this approach may be utilized effectively in appropriately selected cases.

Transradial access for anterior circulation deployment of pipeline embolization device: A case report, literature review, and technical note

Common femoral artery (CFA) transfemoral access (TFA) has been the traditional route for neuroendovascular intervention with flow diversion including the pipeline embolization device (PED) for the treatment of wide-necked aneurysms. Successful deployment requires significant catheter support, thus making alternative access challenging. A 56-year-old-female presented with subarachnoid hemorrhage secondary to a large ruptured posterior communicating artery (PCOM) aneurysm as well as found to have an unruptured left superior cerebellar artery (SCA) aneurysm. Endovascular embolization of PCOM aneurysm via TFA was complicated by a right CFA pseudoaneurysm. The SCA aneurysm was treated 8 weeks later via left TFA with consequent development of a left CFA pseudoaneurysm. Contrasted magnetic resonance angiography revealed recurrence at the neck of the PCOM aneurysm at 4-month follow-up, treated via transradial access (TRA) PED flow diversion to avoid additional groin complications. Anatomic, procedural, and clinical considerations for TRA anterior circulation flow diversion using the PED are reviewed.

The Longissimus Capitis Insertion as a Superficial Landmark for the Sigmoid Sinus: An Anatomical Study

Objective Many external anatomical landmarks have been used for approximating deeper, intracranial structures. Herein, we evaluate the attachment of the longissimus capitis (LC) on the mastoid process as a landmark for the underlying sigmoid sinus.

Methods Adult cadavers underwent dissection of the posterior occiput with special attention to the attachment of the LC muscle. Once the periphery of the muscle's tendon of attachment was determined, a burr hole was made in this area and evaluated internally for its relationship to the sigmoid sinus.

Results From an intracranial view, burr holes on all sides were over the sigmoid sinus and just slightly lateral to the center of the sinus. The distance from the midline to the medial border of the insertion of the LC had a mean of 63.0 ± 7.2 mm. The width of the tendon of insertion of the LC on the mastoid process had a mean of 17.6 ± 5.7 mm. The length of the tendon insertion of the LC had a mean of 14.7 ± 4.7 mm. The distance from the inferior border of the insertion of the LC to the tip of the mastoid process had a mean of 6.2 ± 4.5 mm.

Conclusion To our knowledge, use of the attachment site of the LC on the mastoid process as an external landmark for the underlying sigmoid sinus has not previously been reported. Based on our cadaveric findings, the sigmoid sinus is centered under the attachment of the LC regardless of the width of its tendon.

Multiple flow-related intracranial aneurysms in the setting of contralateral carotid occlusion: Coincidence or association?

The prevalence of intracranial aneurysms (IAs) is higher in patients with internal carotid artery (ICA) stenosis, likely due to alterations in intracranial hemodynamics. Severe stenosis or occlusion of one ICA may result in increased demand and altered hemodynamics in the contralateral ICA, thus increasing the risk of contralateral IA formation. In this article, we discuss a relevant case and a comprehensive literature review as it pertains to the association of ICA stenosis and IA. Our patient was a 50-year-old female with a chronic asymptomatic right ICA occlusion who presented with diffuse subarachnoid hemorrhage. Emergent angiography revealed left-sided A1-A2 junction, paraclinoid, left middle cerebral artery (MCA) bifurcation, and left anterior temporal artery aneurysms. Brisk filling of the right anterior circulation through the anterior communicating artery was also identified, signifying increased demand on the left ICA circulation. Complete obliteration of all aneurysms was achieved with coil embolization and clipping. For our literature review, we searched the PubMed and EMBASE databases for case reports and case series, as well as references in previously published review articles that described patients with concurrent aneurysms and ICA stenosis. We selected articles that provided adequate information about the case presentations to compare aneurysm and patient characteristics. Our review revealed a higher number of patients with multiple aneurysms contralateral (25%) to rather than ipsilateral to (6%), the ICA stenosis. We discuss the pathogenesis and management of multiple flow-related IA in the context of the existing literature related to concurrent ICA stenosis and IA.

Treatment with dimethyl fumarate reduces the formation and rupture of intracranial aneurysms: Role of Nrf2 activation

Oxidative stress and chronic inflammation in arterial walls have been implicated in intracranial aneurysm (IA) formation and rupture. Dimethyl fumarate (DMF) exhibits immunomodulatory properties, partly via activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway which reduces oxidative stress by inducing the antioxidant response element (ARE). This study evaluated the effects of DMF both in vitro, using tumor necrosis factor (TNF)-α-treated vascular smooth muscle cells (VSMC), and in vivo, using a murine elastase model to induce aneurysm formation. The mice were treated with either DMF at 100 mg/kg/day P.O. or vehicle for two weeks. DMF treatment protected VSMCs from TNF-α-induced inflammation as demonstrated by its downregulation of cytokines and upregulation of Nrf2 and smooth muscle cell markers. At higher doses, DMF also inhibited the pro-proliferative action of TNF-α by increasing apoptosis which protected the cells from aponecrosis. In mice, DMF treatment significantly decreased the incidence of aneurysm formation and rupture, at the same time increasing Nrf2 levels. DMF demonstrated a neuroprotective effect in mice with a resultant inhibition of oxidative stress, inflammation, and fibrosis in the cerebrovasculature. This suggests a potential role for DMF as a rescue therapy for patients at risk for formation and rupture of IAs.

Acute Presentation of Vestibular Schwannoma Secondary to Intratumoral Hemorrhage: A Case Report and Literature Review

BACKGROUND

Vestibular schwannomas (VS) are common slow-growing tumors that typically present with the insidious progression of unilateral hearing loss, tinnitus, vertigo, and gait imbalance. Clinically significant intratumoral acute hemorrhage is exceedingly rare and can present with the acute onset of symptoms, neurologic deterioration, and significant dysfunction of cranial nerves VII and VIII. We discuss a 40-year-old man who developed mild hearing loss and headaches over the course of a month before presenting with a large acutely hemorrhagic vestibular schwannoma. In addition, we review the current literature pertaining to this pathology.

CASE PRESENTATION

A previously healthy 40-year-old man with a 1-month history of mild headaches, dizziness, and left-sided hearing loss, tinnitus, and facial numbness presented with the acute onset of severe headache, vomiting, complete left-sided hearing loss, and left-sided facial weakness. Computed tomography and magnetic resonance imaging revealed a 4.1 × 2.7 cm hemorrhagic mass in the left cerebellopontine angle most consistent with VS. The patient subsequently underwent a retrosigmoid craniotomy and resection of the tumor. Pathology was consistent with hemorrhagic VS. Imaging at 1-year follow-up demonstrated no residual or recurrent disease, and facial motor function had completely recovered.

CONCLUSIONS

Histologically, vascular abnormalities and microhemorrhages are nearly ubiquitous across vestibular schwannomas and may contribute to cystic degeneration and rapid tumor growth. However, clinically significant hemorrhage is rarely encountered and is more commonly associated with more profound neurologic sequelae and cranial nerve VII dysfunction. Surgical resection at the time of presentation should be strongly considered to remove the risk of repeat hemorrhage and further deterioration. Our case represents a typical presentation and clinical course for a patient presenting with this rarely encountered pathology.

miR-206 as a Biomarker for Response to Mesalamine Treatment in Ulcerative Colitis

BACKGROUND

MicroRNAs (miRNAs) are important post-translational regulators. Elevated levels of miR-206 in ulcerative colitis (UC) were associated with suppression of anti-inflammatory A3 adenosine receptor (A3AR) expression. However, the relationship of miR-206 to histologic remission in UC patients remains unknown. This study correlates expression levels of miR-206 with histologic remission in patients treated via long-term mesalamine treatment to identify a possible mode of action for this mainstay drug for UC.

METHODS

Expression of miR-206 and its target A3AR were analyzed in HT29 cell line before and after mesalamine treatment (2 mM) at different time points (0, 4, 12, and 24 hours) by qRT-PCR and western blot analysis. Expression of miR-206 and pathological scores of colonoscopic biopsy specimens were studied in 10 UC patients treated with mesalamine treatment for 2 to 6 years.

RESULTS

miR-206 transcripts decreased 2.23-fold (P = 0.0001) 4 hours after 2 mM mesalamine treatment in HT29 colon cells compared with untreated controls. However, the mRNA/protein levels of A3AR increased by 4-fold (P = 0.04) and 2-fold, respectively, in same cells. miR-206 relative expression decreased significantly in patients treated with 4.8 g of mesalamine (P = 0.002) but not with 2.4 g (P = 0.35). Tissue assessment of sequential mesalamine-treated colonoscopic biopsies indicate a strong correlation between downregulation of miR-206 and histologic improvement (R = 0.9111).

CONCLUSION

Mesalamine treatment has an effect on epithelial miRNAs. Downregulation of miR-206 by long-term mesalamine treatment may confer a protective effect in inducing and maintaining histologic remission. Thus, miR-206 expression levels can be utilized as a possible biomarker for therapeutic response to mesalamine treatment.

Differential Association of Microvascular Attributions With Cardiovascular Disease in Patients With Long Duration of Type 1 Diabetes

OBJECTIVE

Independent association of chronic kidney disease (CKD) and proliferative diabetic retinopathy (PDR) with cardiovascular disease (CVD) has not been established. In the Joslin 50-Year Medalist study, characterizing individuals with type 1 diabetes for 50 years or more, we examined the associations of CKD and PDR with CVD, which was validated by another cohort with type 1 diabetes from Finland.

RESEARCH DESIGN AND METHODS

This cross-sectional study characterized U.S. residents (n = 762) with type 1 diabetes of 50 years or longer (Medalists) at a single site by questionnaire, clinical, ophthalmic, and laboratory studies. A replication cohort (n = 675) from the longitudinal Finnish Diabetic Nephropathy Study (FinnDiane) was used. CKD and PDR were defined as estimated glomerular filtration rate <45 mL/min/1.73 m² (CKD stage 3b) and according to the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol, respectively. CVD was based on questionnaires and/or hospital discharge registers. Associations of CVD status with CKD and PDR were analyzed by multivariable logistic regression.

RESULTS

CVD prevalence in the Medalists with CKD and without PDR (+CKD/-PDR) (n = 30) and CVD prevalence in the -CKD/+PDR group (n = 339) were half the prevalence in the +CKD/+PDR group (n = 66) (34.5% and 42.8% vs. 68.2%, P = 0.002). PDR status was independently associated with CVD (odds ratio 0.21 [95% CI 0.08-0.58], P = 0.003) in patients with CKD. Among the Finnish cohort, a trend toward a lower prevalence of CVD in the +CKD/-PDR group (n = 21) compared with the +CKD/+PDR group (n = 170) (19.1% vs. 37.1%, P = 0.10) was also observed.

CONCLUSIONS

Absence of PDR in people with type 1 diabetes and CKD was associated with a decreased prevalence of CVD, suggesting that common protective factors for PDR and CVD may exist.

Pyruvate kinase M2 activation may protect against the progression of diabetic glomerular pathology and mitochondrial dysfunction

Diabetic nephropathy (DN) is a major cause of end-stage renal disease, and therapeutic options for preventing its progression are limited. To identify novel therapeutic strategies, we studied protective factors for DN using proteomics on glomeruli from individuals with extreme duration of diabetes (ł50 years) without DN and those with histologic signs of DN. Enzymes in the glycolytic, sorbitol, methylglyoxal and mitochondrial pathways were elevated in individuals without DN. In particular, pyruvate kinase M2 (PKM2) expression and activity were upregulated. Mechanistically, we showed that hyperglycemia and diabetes decreased PKM2 tetramer formation and activity by sulfenylation in mouse glomeruli and cultured podocytes. Pkm-knockdown immortalized mouse podocytes had higher levels of toxic glucose metabolites, mitochondrial dysfunction and apoptosis. Podocyte-specific Pkm2-knockout (KO) mice with diabetes developed worse albuminuria and glomerular pathology. Conversely, we found that pharmacological activation of PKM2 by a small-molecule PKM2 activator, TEPP-46, reversed hyperglycemia-induced elevation in toxic glucose metabolites and mitochondrial dysfunction, partially by increasing glycolytic flux and PGC-1α mRNA in cultured podocytes. In intervention studies using DBA2/J and Nos3 (eNos) KO mouse models of diabetes, TEPP-46 treatment reversed metabolic abnormalities, mitochondrial dysfunction and kidney pathology. Thus, PKM2 activation may protect against DN by increasing glucose metabolic flux, inhibiting the production of toxic glucose metabolites and inducing mitochondrial biogenesis to restore mitochondrial function.

Proteoglycan-Collagen XV in Human Tissues Is Seen Linking Banded Collagen Fibers Subjacent to the Basement Membrane

Type XV is a large collagen-proteoglycan found in all human tissues examined. By light microscopy it was localized to most epithelial and all nerve, muscle, fat and endothelial basement membrane zones except for the glomerular capillaries or hepatic/splenic sinusoids. This widespread distribution suggested that type XV may be a discrete structural component that acts to adhere basement membrane to the underlying connective tissue. To address these issues, immunogold ultrastructural analysis of type XV collagen in human kidney, placenta, and colon was conducted. Surprisingly, type XV was found almost exclusively associated with the fibrillar collagen network in very close proximity to the basement membrane. Type XV exhibited a focal appearance directly on the surface of, or extending from, the fibers in a linear or clustered array. The most common single arrangement was a bridge of type XV gold particles linking thick-banded fibers. The function of type XV in this restricted microenvironment is expected to have an intrinsic dependence upon its modification with glycosaminoglycan chains. Present biochemical characterization showed that the type XV core protein in vivo carries chains of chondroitin/dermatan sulfate alone, or chondroitin/dermatan sulfate together with heparan sulfate in a differential ratio. Thus, type XV collagen may serve as a structural organizer to maintain a porous meshwork subjacent to the basement membrane, and in this domain may play a key role in signal transduction pathways.

Cannabinoid receptor type-2 stimulation, blockade, and deletion alter the vascular inflammatory responses to traumatic brain injury

BACKGROUND

Immunomodulatory therapies have been identified as interventions for secondary injury after traumatic brain injury (TBI). The cannabinoid receptor type-2 (CB2R) is proposed to play an important, endogenous role in regulating inflammation. The effects of CB2R stimulation, blockade, and deletion on the neurovascular inflammatory responses to TBI were assessed.

METHODS

Wild-type C57BL/6 or CB2R knockout mice were randomly assigned to controlled cortical impact (CCI) injury or to craniotomy control groups. The effects of treatment with synthetic, selective CB2R agonists (0-1966 and JWH-133), a selective CB2R antagonist, or vehicle solution administered to CCI groups were assessed at 1-day after injury. Changes in TNF-α, intracellular adhesion molecule (ICAM-1), inducible nitric oxide synthase (iNOS), macrophage/microglial ionized calcium-binding adaptor molecule, and blood-brain-barrier (BBB) permeability were assessed using ELISA, quantitative RT-PCR, immunohistochemistry, and fluorometric analysis of sodium fluorescein uptake. CB2R knockouts and wild-type mice with CCI injury were treated with a CB2R agonist or vehicle treatment.

RESULTS

TNF-α mRNA increased at 6 hours and 1 to 3 days after CCI; a CB2R antagonist and genetic knockout of the CB2R exacerbated TNF-α mRNA expression. Treatment with a CB2R agonist attenuated TNF-α protein levels indicating post-transcriptional mechanisms. Intracellular adhesion molecule (ICAM-1) mRNA was increased at 6 hours, and at 1 to 2 days after CCI, reduced in mice treated with a CB2R agonist, and increased in CB2R knockout mice with CCI. Sodium fluorescein uptake was increased in CB2R knockouts after CCI, with and without a CB2R agonist. iNOS mRNA expression peaked early (6 hours) and remained increased from 1 to 3 days after injury. Treatment with a CB2R agonist attenuated increases in iNOS mRNA expression, while genetic deletion of the CB2R resulted in substantial increases in iNOS expression. Double label immunohistochemistry confirmed that iNOS was expressed by macrophage/microglia in the injured cortex.

CONCLUSION

Findings demonstrate that the endogenous cannabinoid system and CB2R play an important role in regulating inflammation and neurovascular responses in the traumatically injured brain. CB2R stimulation with two agonists (0-1966 and JWH-133) dampened post-traumatic inflammation, while blockade or deletion of the CB2R worsened inflammation. Findings support previous evidence that modulating the CB2R alters infiltrating macrophages and activated resident microglia. Further investigation into the role of the CB2R on specific immune cell populations in the injured brain is warranted.

Helicobacter pylori associated chronic gastritis, clinical syndromes, precancerous lesions, and pathogenesis of gastric cancer development

Helicobacter pylori (H. pylori) infection is well known to be associated with the development of precancerous lesions such as chronic atrophic gastritis (AG), or gastric intestinal metaplasia (GIM), and cancer. Various molecular alterations are identified not only in gastric cancer (GC) but also in precancerous lesions. H. pylori treatment seems to improve AG and GIM, but still remains controversial. In contrast, many studies, including meta-analysis, show that H. pylori eradication reduces GC. Molecular markers detected by genetic and epigenetic alterations related to carcinogenesis reverse following H. pylori eradication. This indicates that these changes may be an important factor in the identification of high risk patients for cancer development. Patients who underwent endoscopic treatment of GC are at high risk for development of metachronous GC. A randomized controlled trial from Japan concluded that prophylactic eradication of H. pylori after endoscopic resection should be used to prevent the development of metachronous GC, but recent retrospective studies did not show the tendency. Patients with precancerous lesions (molecular alterations) that do not reverse after H. pylori treatment, represent the "point of no return" and may be at high risk for the development of GC. Therefore, earlier H. pylori eradication should be considered for preventing GC development prior to the appearance of precancerous lesions.

Left-sided retrosigmoid craniotomy for the resection of a vestibular schwannoma

The cerebellopontine angle is the site for a wide-range of neoplastic and vascular pathologies. The retrosigmoid craniotomy remains the primary means by which to gain surgical access to this anatomically complex region. We present our standard technique for the completion of a retrosigmoid craniotomy and the resection of a left-sided vestibular schwannoma. Anatomy pertinent to the approach, including, the transverse and sigmoid sinuses, cranial nerves, and internal auditory canal (IAC) is displayed. Special emphasis is placed on patient positioning, adequate bone removal, and tumor resection. The drilling of the IAC and tumor dissection from the VII-VIII complex is also highlighted. Hearing preservation was achieved. The video can be found here: http://youtu.be/FFZju5vcBi0 .

Successful treatment of a traumatic carotid pseudoaneurysm with the Pipeline stent: Case report and review of the literature

BACKGROUND

Traumatic intracranial pseudoaneurysms remain one of the most difficult vascular lesions to treat. In the case of traumatic pseudoaneurysms that may not be treated with parent vessel sacrifice, some flow diversion strategy such as stent-assistance or use of a flow diversion device is usually necessary.

CASE DESCRIPTION

In this study we describe endovascular parent vessel wall-remodeling/endoluminal reconstruction and traumatic pseudoaneurysm thrombosis through the use of the Pipeline stent and review recent reports concerning indications, safety, and efficacy for alternative pathology.

CONCLUSION

Although currently not routinely employed in the treatment of traumatic pseudoaneurysms, the Pipeline stent may represent a safe and effective treatment alternative achieving complete endoluminal reconstruction of the damaged vessel wall.

Intracranial vertebral artery dissections: evolving perspectives

Intracranial vertebral artery dissection (VAD) represents the underlying etiology in a significant percentage of posterior circulation ischemic strokes and subarachnoid hemorrhages. These lesions are particularly challenging in their diagnosis, management, and in the prediction of long-term outcome. Advances in the understanding of underlying processes leading to dissection, as well as the evolution of modern imaging techniques are discussed. The data pertaining to medical management of intracranial VADs, with emphasis on anticoagulants and antiplatelet agents, is reviewed. Surgical intervention is discussed, including, the selection of operative candidates, open and endovascular procedures, and potential complications. The evolution of endovascular technology and techniques is highlighted.

A cannabinoid type 2 receptor agonist attenuates blood-brain barrier damage and neurodegeneration in a murine model of traumatic brain injury

After traumatic brain injury (TBI), inflammation participates in both the secondary injury cascades and the repair of the CNS, both of which are influenced by the endocannabinoid system. This study determined the effects of repeated treatment with a cannabinoid type 2 receptor (CB(2) R) agonist on blood-brain barrier integrity, neuronal degeneration, and behavioral outcome in mice with TBI. We also looked for the presence of a prolonged treatment effect on the macrophage/microglial response to injury. C57BL/6 mice underwent controlled cortical impact (CCI) and received repeated treatments with a CB(2) R agonist, 0-1966, or vehicle. After euthanasia at 6 hr or 1, 2, 3, or 7 days postinjury, brains were removed for histochemical analysis. Blood-brain barrier permeability changes were evaluated by using sodium fluorescein (NaF). Perilesional degenerating neurons, injury volumes, and macrophage/microglia cells were quantified by stereological methods. Rota-rod and open-field testing were performed to evaluate motor function and natural exploratory behavior in mice. 0-1966 Treatment resulted in a significant reduction in NaF uptake and number of degenerating neurons compared with the vehicle-treated group. 0-1966-Treated mice demonstrated improvement on rota-rod and open-field testing compared with vehicle-treated mice. These changes in CCI mice treated with 0-1966 were associated with a prolonged reduction in macrophage/microglia cell counts. In conclusion, repeated treatments with a CB(2) R agonist, 0-1966, result in attenuated blood-brain barrier disruption and neuronal degeneration. In addition, repeated treatment with 0-1966 shows prolonged treatment effects on behavior and the macrophage/microglia cell response over several days.

Nociceptive neuropeptide increases and periorbital allodynia in a model of traumatic brain injury

OBJECTIVE

This study tests the hypothesis that injury to the somatosensory cortex is associated with periorbital allodynia and increases in nociceptive neuropeptides in the brainstem in a mouse model of controlled cortical impact (CCI) injury.

METHODS

Male C57BL/6 mice received either CCI or craniotomy-only followed by weekly periorbital von Frey (mechanical) sensory testing for up to 28 days post-injury. Mice receiving an incision only and naïve mice were included as control groups. Changes in calcitonin gene-related peptide (CGRP) and substance P (SP) within the brainstem were determined using enzyme-linked immunosorbent assay and immunohistochemistry, respectively. Activation of ionized calcium-binding adaptor molecule-1-labeled macrophages/microglia and glial fibrillary acidic protein (GFAP)-positive astrocytes were evaluated using immunohistochemistry because of their potential involvement in nociceptor sensitization.

RESULTS

Incision-only control mice showed no changes from baseline periorbital von Frey mechanical thresholds. CCI significantly reduced mean periorbital von Frey thresholds (periorbital allodynia) compared with baseline and craniotomy-only at each endpoint, analysis of variance P < .0001. Craniotomy significantly reduced periorbital threshold at 14 days but not 7, 21, or 28 days compared with baseline threshold, P < .01. CCI significantly increased SP immunoreactivity in the brainstem at 7 and 14 days but not 28 days compared with craniotomy-only and controls, P < .001. CGRP levels in brainstem tissues were significantly increased in CCI groups compared with controls (incision-only and naïve mice) or craniotomy-only mice at each endpoint examined, P < .0001. There was a significant correlation between CGRP and periorbital allodynia (P < .0001, r = -0.65) but not for SP (r = 0.20). CCI significantly increased the number of macrophage/microglia in the injured cortex at each endpoint up to 28 days, although cell numbers declined over weeks post-injury, P < .001. GFAP(+) immunoreactivity was significantly increased at 7 but not 14 or 28 days after CCI, P < .001. Craniotomy resulted in transient periorbital allodynia accompanied by transient increases in SP, CGRP, and GFAP immunoreactivity compared with control mice. There was no increase in the number of macrophage/microglia cells compared with controls after craniotomy.

CONCLUSION

Injury to the somatosensory cortex results in persistent periorbital allodynia and increases in brainstem nociceptive neuropeptides. Findings suggest that persistent allodynia and increased neuropeptides are maintained by mechanisms other than activation of macrophage/microglia or astrocyte in the injured somatosensory cortex.

Stent-Assisted Coiling of Wide-Necked Aneurysms in the Setting of Acute Subarachnoid Hemorrhage

BACKGROUND:

Stent-assisted coiling in the setting of subarachnoid hemorrhage remains controversial. Currently, there is a paucity of data regarding the utility of this procedure and the risks of hemorrhagic and ischemic complications.

OBJECTIVE:

To assess the utility of stent-assisted coil embolization and pretreatment with antiplatelet agents in the management of ruptured wide-necked aneurysms.

METHODS:

A retrospective study of 65 patients with ruptured wide-necked aneurysms treated with stent-assisted coiling. Patients with hydrocephalus or a Hunt and Hess grade ≥ III received a ventriculostomy before endovascular intervention. Patients were treated intraoperatively with 600 mg of clopidogrel and maintained on daily doses of 75 mg of clopidogrel and 81 mg of aspirin. The Glasgow outcome scale (GOS) score was recorded at the time of discharge. We identified major bleeding complications secondary to antiplatelet therapy and cases of in-stent thrombosis that required periprocedural thrombolysis.

RESULTS:

Of the aneurysms, 66.2% arose within the anterior circulation; 69.2% of patients presented with hydrocephalus or a Hunt and Hess grade ≥ III and required a ventriculostomy. A good outcome (GOS of 4 or 5) was achieved in 63.1% of patients, and the overall mortality rate was 16.9%. There were 10 (15.38%) major complications associated with bleeding secondary to antiplatelet therapy (5 patients, 7.7%) or intraoperative in-stent thrombosis (5 patients, 7.7%). Three (4.6%) patients had a fatal hemorrhage.

CONCLUSION:

Our findings suggest that stent-assisted coiling and routine treatment with antiplatelet agents is a viable option in the management of ruptured wide-necked aneurysms.

Analysis of Nonmodifiable Risk Factors for Intracranial Aneurysm Rupture in a Large, Retrospective Cohort

Background:

The risk factors predictive of intracranial aneurysm rupture remain incompletely defined.

Objective:

To examine the association between various nonmodifiable risk factors and aneurysm rupture in a large cohort of patients evaluated at a single institution.

Methods:

A retrospective analysis of patients admitted to a cerebrovascular facility between January 2006 and 2010 with a primary diagnosis of cerebral aneurysm. Aneurysms were divided into 2 groups: unruptured or ruptured. The dome diameter, aspect ratio (AR), location, sidedness, neck morphology, and multiplicity were entered into a central database. A full model was constructed, and a systematic removal of the least significant variables was performed in a sequential fashion until only those variables reaching significance remained.

Results:

We identified 2347 patients harboring 5134 individual aneurysms, of which 34.90% were ruptured and 65.09% were unruptured. On admission, 25.89% of aneurysms with a dome diameter &lt;10 mm and 58.33% of aneurysms with a dome &gt;10 mm were ruptured (P &lt; .001). Of aneurysms with an AR &gt;1.6, 52.44% presented following a rupture (P &lt; .001). The highest incidence of rupture (69.21%) was observed in aneurysms with an AR &gt;1.6, dome diameter &lt;10 mm, and a deviated neck. Deviated neck-type aneurysms had a significantly greater incidence of rupture than classical necktype aneurysms (P &lt; .001).

Conclusion:

An AR &gt;1.6, dome diameter &gt;10 mm, a deviated neck, and right-sidedness are independently associated with aneurysm rupture.

Computed tomography perfusion–based selection of patients for endovascular recanalization

Intravenous and intraarterial recombinant tissue plasminogen activator remains underutilized in the treatment of acute ischemic stroke, largely due to strict adherence to the concept of the therapeutic time window for administration. Recent efforts to expand the number of patients eligible for thrombolysis have been mirrored by an evolution in endovascular recanalization technology and techniques. As a result, there is a growing need to establish efficient and reliable means by which to select candidates for endovascular intervention beyond the traditional criteria of time from symptom onset. Perfusion imaging techniques, particularly CT perfusion used in combination with CT angiography, represent an increasingly recognized means by which to identify those patients who stand to benefit most from endovascular recanalization. Additionally, CT perfusion and CT angiography appear to provide sufficient data by which to exclude patients in whom there is little chance of neurological recovery or a substantial risk of postprocedure symptomatic intracranial hemorrhage. The authors review the current literature as it pertains to the limitations of time-based selection of patients for intervention, the increasing utilization of endovascular therapy, and the development of a CT perfusion-based selection of acute stroke patients for endovascular recanalization. Future endeavors must prospectively evaluate the utility and safety of CT perfusion-based selection of candidates for endovascular intervention.

Acute effects of a selective cannabinoid-2 receptor agonist on neuroinflammation in a model of traumatic brain injury

Proposed therapeutic strategies for attenuating secondary traumatic brain injury (TBI) include modulation of acute neuroimmune responses. The goal of this study was to examine the acute effects of cannabinoid-2 receptor (CB(2)R) modulation on behavioral deficits, cerebral edema, perivascular substance P, and macrophage/microglial activation in a murine model of TBI. Thirty male C57BL/6 mice underwent sham surgery, or cortical contusion impact injury (CCI). CCI mice received vehicle or the CB(2)R agonist 0-1966 at 1 and 24 h after injury. Performance on the rotarod, forelimb cylinder, and open-field tests were evaluated before and at 48 h after sham or CCI surgery. Cerebral edema was evaluated using the wet-dry weight technique. Immunohistochemical analysis was used to examine changes in substance P and macrophage/microglia-specific Iba1 protein immunoreactivity. Locomotor performance and exploratory behavior were significantly improved in mice receiving 0-1966 (CB(2)R agonist) compared to vehicle-treated mice. Significant reductions were found for cerebral edema, number of perivascular areas of substance P immunoreactivity, and number of activated macrophages/microglial cells in the injured brains of 0-1966-treated mice compared to vehicle-treated mice. The findings show that the effects of the CB(2)R agonist 0-1966 on edema, substance P immunoreactivity, and macrophage/microglial activation, were associated with recovery of acute motor and exploratory deficits. This study provides evidence of acute neuroprotective effects derived from selective CB(2)R activation that may represent an avenue for further development of novel therapeutic agents in the treatment of TBI.

Commentary: academic health centers as accountable care organizations

Academic health centers (AHCs) have opportunities to advance the agenda of U.S. health care reform by tying the needs of populations to the AHCs' missions and areas of expertise. Serving as accountable care organizations and advancing the agenda of the patient-centered medical home are two important potential actions AHCs can take. By fostering discovery, learning, and care through rational organizational structures that meet the needs of populations and bend the curve of growing health care expenditures, AHCs can lead health care reform in the 21st century.

Repeated exposure to acid and bile selectively induces colonic phenotype expression in a heterogeneous Barrett's epithelial cell line

Barrett's epithelium is a precancerous, specialized columnar metaplasia in the distal esophagus. We demonstrate the changes in cellular phenotype in a non-neoplastic Barrett's cell line (BAR-T), following exposure to acid and bile salt, the two important components of gastroesophageal refluxate. Cell phenotypes in BAR-T cell line were quantified by fluorescence-activated cell sorting (FACS) using monoclonal antibodies against markers: cytokeratin 8/18 (CK8/18) for columnar, CK4 for squamous, mAbDas-1 for colonic epithelial cell phenotype and p75NTR for esophageal progenitors. Cells were exposed for 5 min each day to 200 microM glycochenodeoxycholic acid at pH 4, pH 6 and pH 7.4 or only to acid (pH 4) for up to 6 weeks. The BAR-T cell line comprised 35+/-5.2% CK8/18, 32+/-3.5% mAbDas-1, 9.5+/-3% CK4 and 4+/-2.5% p75NTR-positive cells. Single exposure to acid and or bile did not change cell phenotypes. However, chronic treatment for at least 2 weeks significantly enhanced (P<0.05) the expression of colonic phenotype and CK8/18-positive cells, as evidenced by FACS analysis. Bile salt at pH 4 and bile salt followed by acid (pH 4) in succession were the strongest stimulators (P<0.01) for induction of colonic phenotype cells. Squamous (CK4(+)) phenotype did not change by the treatments. Cox-2 expression was induced after acute treatment and increased to twofold during chronic treatment, particularly in response to acidic pH. We conclude that BAR-T cells can be utilized as an 'in vitro' model to study the effect of environmental factors and their influence on the cellular phenotype and molecular changes in the pathogenesis of esophageal cancer.

Effect of eradication of Helicobacter pylori on the histology and cellular phenotype of gastric intestinal metaplasia

BACKGROUND & AIMS

Eradication of Helicobacter pylori appears to reduce gastric cancer incidence. We examined the effect of successful H pylori therapy on histology, phenotype of gastric intestinal metaplasia (GIM) (complete vs incomplete), and expression of several biomarkers related to carcinogenesis.

METHODS

Ninety-six H pylori-positive patients from Japan were treated successfully and followed up prospectively over 4 years with yearly endoscopy and were classified into 3 groups: group CG, chronic gastritis without GIM (n = 36); group IM, chronic gastritis with GIM (n = 33); group DYS, and GIM with dysplasia/cancer in a different location of the stomach (n = 27). A total of 288 endoscopic procedures were performed. Histology, mucin-histochemistry, and immunoperoxidase assays using monoclonal antibodies (mAbs) for cell phenotype (monoclonal antibody Das-1/colonic) and for neoplasia (TC22 and p53) were performed.

RESULTS

The GIM histologic score was higher in group DYS than in group IM (P < .05) and group CG (P < .0001). The GIM scores did not change in groups IM and DYS over 4 years. mAb Das-1 reactivity was higher in group DYS (63%) than in group IM (39%) and group GC (0%). After eradication of H pylori, mAb Das-1 reactivity disappeared in 40% of patients (P < .0001) despite the unchanged GIM scores, and regression of TC22-4 was noted in the same patients.

CONCLUSIONS

H pylori eradication does not reduce the histologic GIM score, but changes the cellular phenotype of GIM. This change of phenotype may be an important factor in the reduction of cancer incidence after eradication of H pylori.

Elastin gene mutations in transgenic mice

We have constructed several rat tropoelastin minigene recombinants encoding the complete sequence of rat tropoelastin, two isoforms of rat tropoelastin and a truncated tropoelastin lacking the domains encoded by exons 19-31 of the rat gene. Coding and non-coding domains in all these recombinants were placed under the transcriptional control of 3 kb of the promoter domain of the rat tropoelastin gene. These minigenes were used to prepare a total of 28 separate founder lines of transgenic mice. A species-specific reverse-transcriptase polymerase chain reaction (RT-PCR) assay was established to demonstrate the synthesis of rat and mouse tropoelastin mRNA in several tissues obtained from both neonatal and adult transgenic mice. Thermolytic digestion of insoluble elastin isolated from several neonatal mouse tissues revealed the presence of rat tropoelastin peptides in progeny from all those founder mice in which detectable levels of rat tropoelastin mRNA were noted. Phenotypic and histopathological assessment of transgenic and non-transgenic animals revealed the development of two diverse elastic tissue disorders. The progeny of two separate founder lines overexpressing the rat tropoelastin isoform lacking exon 33, developed an emphysematous phenotype in early adulthood. In contrast, transgenic mice, in which expression of the truncated rat tropoelastin minigene lacking exons 19-31 had been observed, died of a ruptured ascending aortic aneurysm. Tropoelastin gene mutations, therefore, will result in heritable disorders of elastic tissue. Moreover, different mutations in the tropoelastin gene will be responsible for very different abnormalities in elastic tissue function.

The molecular structure of human tissue type XV presents a unique conformation among the collagens

Establishing the structure of the non-fibrillar collagens has provided a unique perspective to understanding their specialized functions in the extracellular matrix. These proteins exhibit very diverse conformations and supramolecular assemblies. Type XV collagen is a large macromolecule distinguished by a highly interrupted collagenous domain and many utilized sites of attachment for CS (chondroitin sulfate) and HS (heparan sulfate) glycosaminoglycan chains. It is present in most basement membrane zones of human tissues, where it is found closely associated with large collagen fibrils. To determine the molecular shape and organization of type XV, the protein was purified from human umbilical cords by salt extraction, and by ion-exchange and antibody-affinity chromatography. The representation of type XV in one of its most abundant tissue sources is estimated at only (1-2)x10(-4)% of dry weight. The molecules examined by transmission electron microscopy after rotary shadowing were visualized in multiple forms. Relatively few type XV monomers appeared elongated and kinked; most molecules were found in a knot/figure-of-eight/pretzel configuration not previously described for a collagen. Collective measurements of these populations revealed an average length of 193+/-16 nm. At the N-terminal end, identified by C-terminal antibody binding, were three 7.7 nm-diameter spheres, corresponding to TSPN-1 (N-terminal module of thrombospondin-1) modules, and attached to the collagen backbone by a short linker. The type XV monomers show the ability to self-assemble into higher-order structures. Some were arranged in complex clusters, but simpler oligomers, which may represent intermediates, were observed in a cruciform pattern with intermolecular binding sites that probably originate in the interruption sequences. The morphology of type XV is thus the antithesis of the fibrillar collagens, and the shape attains the required flexibility to form the spectrum of interconnecting links between banded fibrils at the basement membrane/interstitial border. These type XV structures may act as a biological 'spring' to stabilize and enhance resilience to compressive and expansive forces, and the multimers, in particular, with selective complements of many localized CS and HS chains, may be instrumental in spatial and temporal recruitment of modulators in growth, development and pathological processes.

GROalpha is highly expressed in adenocarcinoma of the colon and down-regulates fibulin-1

PURPOSE

The growth-related oncogene alpha (GROalpha) is a secreted interleukin-like molecule that interacts with the CXCR2 G-protein-coupled receptor. We found that the mRNA and protein products of GROalpha are more highly expressed in neoplastic than normal colon epithelium, and we studied potential mechanisms by which GROalpha may contribute to tumor initiation or growth.

EXPERIMENTAL DESIGN

Cell lines that constitutively overexpress GROalpha were tested for growth rate, focus formation, and tumor formation in a xenograft model. GROalpha expression was determined by Affymetrix GeneChip (241 microdissected colon samples), real-time PCR (n = 32), and immunohistochemistry. Primary colon cancer samples were also employed to determine copy number changes and loss of heterozygosity related to the GROalpha and fibulin-1 genes.

RESULTS

In cell cultures, GROalpha transfection transformed NIH 3T3 cells, whereas inhibition of GROalpha by inhibitory RNA was associated with apoptosis, decreased growth rate, and marked up-regulation of the matrix protein fibulin-1. Forced expression of GROalpha was associated with decreased expression of fibulin-1. Expression of GROalpha mRNA was higher in primary adenocarcinomas (n = 132), adenomas (n = 32), and metastases (n = 52) than in normal colon epithelium (P < 0.001). These results were confirmed by real-time PCR and by immunohistochemistry. Samples of primary and metastatic colon cancer showed underexpression of fibulin-1 when compared with normal samples. There were no consistent changes in gene copy number of GROalpha or fibulin-1, implying a transcriptional basis for these findings.

CONCLUSION

Elevated expression of GROalpha is frequent in adenocarcinoma of the colon and is associated with down-regulation of the matrix protein fibulin-1 in experimental models and in clinical samples. GROalpha overexpression abrogates contact inhibition in cell culture models, whereas inhibition of GROalpha expression is associated with apoptosis. Importantly, coexpression of fibulin-1 with GROalpha abrogates key aspects of the transformed phenotype, including tumor formation in a murine xenograft model. Targeting GRO proteins may provide new opportunities for treatment of colon cancer.

Autoimmunity against human tropomyosin isoforms in ulcerative colitis: localization of specific human tropomyosin isoforms in the intestine and extraintestinal organs

BACKGROUND

Tropomyosins (TMs) are microfilament cytoskeletal proteins, and 5 major human TM isoforms (hTM1-5) are described. hTMs, particularly isoform 5 (hTM5), is capable of inducing autoantibodies and T-cell response in ulcerative colitis (UC). However, cellular localization of hTM isoforms in the colon and in extraintestinal organs commonly involved in UC is unknown.

METHODS

Using isoform-specific monoclonal antibodies, we localized hTMs through immunoperoxidase assay in normal colon (n = 12), small intestine (n = 14), esophagus (n = 10), skin (n = 19), eye (n = 12), gallbladder (n = 16), liver, including bile duct at the porta hepatis (n = 4), lungs (n = 4), and pancreas (n = 4).

RESULTS

There is intense expression of hTM5, but not other isoforms, in the epithelium of the colon, gallbladder, and skin. In the eye, hTM5 is expressed only in the nonpigmented ciliary epithelium. Although extrahepatic and interlobar large ductal biliary epithelium was positive, bile canaliculi at the portal tract are negative. The immunoreactivity in epithelial cells from these organs is diffuse cytoplasmic and along the periphery. In colon epithelium, there is intense expression along basolateral areas and luminal (apical) surface. In the small intestinal epithelium, however, hTM5 expression is weak and distinctly different than in the colon. hTM5 was not detected in the squamous epithelium of the esophagus, although it was strongly positive in the skin. hTM1, hTM2, and hTM3 are localized predominantly in smooth muscle of the intestine and blood vessel wall but not the epithelium. HTM4 is localized in the endothelial cells and basement membrane of the colonic epithelium.

CONCLUSIONS

hTM5 is the predominant isoform in the epithelium of colon and extraintestinal organs commonly involved in UC. The unique expression of hTM5 may allow its interaction with effector immune cells involved in the immunopathogenesis of UC and its extraintestinal manifestations.

Preferential expression of cyclooxygenase-2 in colonic-phenotype of gastric intestinal metaplasia: association with helicobacter pylori and gastric carcinoma

OBJECTIVES

Gastric intestinal metaplasia (GIM) associated with H. pylori (HP) has been considered a premalignant lesion. However, GIM phenotype associated with HP infection and gastric cancer is unclear. The expression of COX-2 in relation to GIM phenotype is also unknown.

METHODS

We evaluated cellular phenotype and COX-2 expression in the GIM from HP-positive and -negative patients from Japan in the absence of gastric cancer (n = 31) by using a colon epithelium specific monoclonal antibody (mAb Das-1) and anti-COX-2 antibody. COX-2 expression was also examined in patients with gastric cancer (n = 34), both in the cancer and in the GIM areas away from the cancer field.

RESULTS

Sixty-eight percent of HP-positive GIM reacted with mAb Das-1, whereas the reactivity in the HP-negative GIM was only 25% (P < 0.001). The COX-2 expression was present in 32% of HP-positive GIM and in only 9% of HP-negative GIM (P < 0.001). In the cancer group, COX-2 expression was localized both in the cancer area (94%) and in the GIM (82%) away from the cancer. Each of the COX-2-positive tissue was also positive to mAb Das-1.

CONCLUSION

HP infection is highly associated with the development of colonic-phenotype of GIM, and about half of them expressed COX-2. COX-2 expression was frequent in both gastric cancer and the GIM adjacent to the cancer. The results suggest that the presence of mAb Das-1 and COX-2 reactivity in the GIM identify the subgroup of patients who may be at risk for gastric cancer and may need close surveillance.