Clonidine-induced hypertension in a patient with a spinal lesion

OBJECTIVE: To report a case of possible clonidine-induced hypertension (by Naranjo score) in a patient with a C4 spinal lesion. BACKGROUND: Clonidine is a medication long used to treat hypertension, and it is still used in the treatment of refractory hypertension. Although effective, clonidine use is hindered by adverse effects and its dual mechanism of action. CASE SUMMARY: A 39-year-old white, quadriplegic man with poorly controlled pain displayed many characteristics consistent with autonomic dysfunction (e.g., C4 spinal lesion, orthostatic hypotension, hypertension). The patient was routinely receiving transdermal clonidine and also received transdermal nitroglycerin paste as needed for control of acute hypertensive episodes. On the recommendation of the home healthcare pharmacists, clonidine was discontinued. Since that time, the patient's blood pressure and the use of emergent antihypertensive treatment have decreased significantly (maximum systolic and diastolic BP by approximately 50 and 25 mm Hg, respectively). CONCLUSIONS: Many of the characteristics of autonomic dysfunction, such as refractory hypertension, can seem selective for the use of clonidine and, because of its reliance on central alpha(2)-activity for its hypotensive effects, clonidine may induce hypertension in patients with autonomic dysfunction. Clonidine should be used with great caution when autonomic dysfunction is suspected.     

The excitatory postsynaptic density is a size exclusion diffusion environment

Receptors are concentrated in the postsynaptic membrane but can enter and exit synapses rapidly during both basal turnover and processes of synaptic plasticity. How the exchange of receptors by lateral diffusion between synaptic and extrasynaptic areas is regulated remains largely unknown. We investigated the structural properties of the postsynaptic membrane that allow these movements by addressing the diffusion behaviors of AMPA receptors (AMPARs) and different lipids. Using single molecule tracking we found that not only AMPARs but also lipids, which are not synaptically enriched, display confined diffusion at synapses. Each molecule type displays a different average confinement area, smaller molecules being confined to smaller areas. Glutamate application increases the mobility of all molecules. The structure of the synaptic membrane is thus probably organized as a size exclusion matrix and this controls the rate of exchange of molecules with the extrasynaptic membrane.     

Stent grafting of acute hepatic artery bleeding following pancreatic head resection

The purpose of this study was to report the potential of hepatic artery stent grafting in cases of acute hemorrhage of the gastroduodenal artery stump following pancreatic head resection. Five consecutive male patients were treated because of acute, life-threatening massive bleeding. Instead of re-operation, emergency angiography, with the potential of endovascular treatment, was performed. Because of bleeding from the hepatic artery, a stent graft (with the over-the-wire or monorail technique) was implanted to control the hemmorhage by preserving patency of the artery. The outcome was evaluated. In all cases, the hepatic artery stent grafting was successfully performed, and the bleeding was immediately stopped. Clinically, immediately after the procedure, there was an obvious improvement in the general patient condition. There were no immediate procedure-related complications. Completion angiography (n=5) demonstrated control of the hemorrhage and patency of the hepatic artery and the stent graft. Although all patients recovered hemodynamically, three individuals died 2 to 10 days after the procedure. The remaining two patients survived, without the need for re-operation. Transluminal stent graft placement in the hepatic artery is a safe and technically feasible solution to control life-threatening bleeding of the gastroduodenal artery stump.     

Initial clinical experience with the 4-F self-expanding XPERT stent system for infrapopliteal treatment of patients with severe claudication and critical limb ischemia

PURPOSE: To evaluate the primary success and short-term patency associated with a new 4-F sheath-compatible self-expanding nitinol stent after failed conventional angioplasty of distal popliteal and infrapopliteal lesions in severe lifestyle-limiting claudication (LLC) and chronic critical limb ischemia (CLI). MATERIALS AND METHODS: Between May 2003 and July 2005, 35 patients with Rutherford category 3-5 disease (16 patients with CLI, 19 patients with LLC) underwent percutaneous transluminal angioplasty (PTA) and stent implantation. Indications for stent placement were residual stenosis, flow-limiting dissections, or elastic recoil after PTA. Before and after the intervention and during the 6-month follow-up, clinical investigation, color-flow and duplex Doppler ultrasonography, and digital subtraction angiography were performed. Technical success, primary patency at 6 months, clinical improvement as defined by Rutherford with clinical and hemodynamic measures, and complications were evaluated. RESULTS: A total of 22 patients underwent distal popliteal artery stent placement and 13 underwent tibioperoneal artery stent placement. Stent implantation was successfully performed in all patients. After stent placement, the primary cumulative patency rate for the study group at 6 months was 82%. The mean resting ankle-brachial index at baseline was 0.50 +/- 0.16 and significantly increased to 0.90 +/- 0.17 at 12-24 hours after intervention and 0.82 +/- 0.24 at latest follow-up (P < .001 for both). The sustained clinical improvement rate was 80% at the 6-month follow-up. The 6-month limb salvage rate regarding major amputation was 100%. The rate of major complications was 17%. CONCLUSIONS: Infrapopliteal application of the new nitinol stent is a safe, feasible, and effective method with good short-term patency rate in the treatment of severe LLC and chronic CLI.     

Expressions of Topoisomerase IIα and BCRP in Metastatic Cells are Associated with Overall Survival in Small Cell Lung Cancer Patients

The aim of this study was to investigate the mRNA expression levels of multidrug resistance-associated proteins in chemo-na?ve metastatic lung cancer cells and to determine the correlation with response to chemotherapy and overall survival. Metastatic cells were obtained by transbronchial fine needle aspiration biopsy of enlarged mediastinal lymph nodes in 14 patients with small cell lung cancer (SCLC) and 7 patients with non-small cell lung cancer (NSCLC). After cytological confirmation of lung cancer type, total RNA was extracted from biopsy samples and reverse transcribed to cDNA, and real-time PCR for the genes of interest [P-glycoprotein (P-gp), multidrug resistance protein 1 (MRP1), breast cancer resistance protein (BCRP), lung resistance protein (LRP) and topoisomerase IIα (TOPIIα)], was performed. We observed significantly decreased expression of BCRP and significantly increased expression of TOPIIα in metastatic SCLC cells compared to NSCLC. Furthermore, in SCLC high topoisomerase IIα and low BCRP expression levels positively correlated with longer overall survival. Our results showed higher expression levels of BCRP as well as lower levels of topoisomerase IIα in chemo-na?ve metastatic cells in NSCLC than in SCLC. These results correlate with previous observations that metastatic SCLC cells at the beginning of chemotherapy are potentially more sensitive to chemotherapeutic agents while in metastatic NSCLC cells resistance is usually inherent. We also showed that altered levels of topoisomerase IIα and BCRP in SCLC are important factors that contribute to resistance to chemotherapeutics that interfere with the enzyme and/or DNA and are highly associated with overall survival.     

Cutaneous polyarteritis nodosa in children: three cases

INTRODUCTION: Polyarteritis nodosa is a necrotizing vasculitis of small and medium-size arteries. The cutaneous form of polyarteritis nodosa follows a chronic course, characterized by recurrent episodes limited to skin, muscles and joints. This entity differs from systemic polyarteritis nodosa in the absence of visceral involvement. This form is rare in children, we describe three cases. CASE REPORTS: We describe three girls with a mean age of 11 years (range: 8-13). They presented painful subcutaneous edematous nodules, arthralgia and fever. Physical examination revealed livedo reticularis (2 cases) and pharyngeal infection (1 case). Laboratory findings showed an inflammatory syndrome. Skin biopsy supported diagnosis of polyarteritis nodosa. The course was characterized by periods of remission disrupted by exacerbations, well controlled by salicylotherapy, colchicine, dapsone or penicillin. Corticosteroid therapy was used only for invalidating symptoms. There was no systemic involvement after 2, 5 and 6 years of follow up. DISCUSSION: Cutaneous polyarteritis nodosa in children must be suspected in presence of fever, subcutaneous nodules, livedo reticularis and arthralgia. Prognosis is usually benign, so we recommend no aggressive treatment. In view of the tendency to relapse, long-term follow-up is appropriate, before confirming diagnosis.     

Hilar cholangiocarcinoma: radiological assessment of resectability

A pre-operative study of 31 patients with proximal cholangiocarcinoma was carried out with ultrasonography (US), duplex sonography (DS), computed tomography (CT), percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiography (ERC) and angiography. US, DS and PTC are the most effective techniques for pre-operative staging assessment of proximal cholangiocarcinoma. A tumour was visualised by US in 89% of cases, and the extent of extraductal tumour invasion was correctly established in 64%. Lobar segmental tumour extension was correctly documented in 80% of cases; however, the exact definition of tumour extension required the use of PTC. Vascular patency was correctly visualised by DS in 85% of cases. Altogether, tumour invasion was correctly documented in 68% in cases. In the event of radiologically localised tumour extension, radiological interpretation was correct in 64% of cases. The extent of tumour infiltration was radiologically underestimated in 36% of cases, especially in documenting lymph node metastases, infiltration of the hepato-duodenal ligament and segmental liver invasion. Correspondence to: J. Triller     

Use of a mechanical thrombectomy device to recanalize a subacutely occluded aortohepatic bypass after orthotopic liver transplantation.

PURPOSE: To report the use of a rotational thrombectomy device for recanalization of a thrombosed hepatic artery bypass graft in an orthotopic liver transplant (OLT). CASE REPORT: Six months after a second OLT in a 52-year-old man, an iliac conduit used for an aortohepatic bypass became occluded, interrupting arterial supply to the liver transplant. The 8-F Straub Rotarex system was used to successfully remove clot from the bypass graft, avoiding embolization to the hepatic arteries. The recanalized conduit has remained patent for 1 year with the patient on an anticoagulation regimen. CONCLUSIONS: The Rotarex thrombectomy system may be considered an alternative to other percutaneous interventions for the treatment of occluded bypass conduits supplying a liver transplant.