Pancreaticoduodenectomy in the era of evidence based medicine

The aim of this comprehensive literature review was to analyse evidence based data in the field of pancreaticoduodenectomy. Pylorus preserving does reduce mortality or morbidity of the standard procedure and could increase the risk of delayed gastric emptying. Pancreaticogastrostomy does not decrease the rate of postoperative pancreatic fistula and is not superior to the pancreaticojejunal anastomosis which is more physiological. No other procedure (chemical occlusion, octreotide, stenting) has been demonstrated to prevent pancreatic fistula. Octreotide injection could be advocated in centres where there is a high rate of pancreatic fistula, when pancreatic parenchyma is soft and the main pancreatic duct thin. Intra-abdominal drainage is not beneficial and could be associated with some morbidity. Its use needs to be further evaluated. When a resection is done for pancreatic cancer, less than 5% of patients are a live five years after surgery with postoperative mortality rate of 5% in expert centres and a high morbidity rate (25-50%). Extended lymphadenectomy does not increase survival. The first trials showed that adjuvant therapies could be beneficial for pancreatic cancers, but further trials did not confirm these findings. Adjuvant therapy is not validated for pancreatic cancers and needs to be considered only in the settings of clinical trials.     

Toxoplasmosis. Two observations and a specification

On the basis of two interesting observations of toxoplasmic disease the Authors attempt to interpret the various pathological pictures, comparing two different formulations of toxoplasmic disease: that of Sabin and that of more modern AA.     

Subacute sclerosing panencephalitis in the differential diagnosis of encephalitis

The authors describe five cases of subacute sclerosing panencephalitis (SSPE) identified through the California Encephalitis Project that emphasize the importance of considering SSPE in the differential diagnosis of encephalitis, particularly among pediatric patients. SSPE was not suspected in the differential diagnosis of three of the cases until results of measles testing were known. The diagnosis of SSPE is often not considered by clinicians because of its rarity in the United States and the nonspecific clinical manifestations at onset.     

Anti-AIDS agents. 46. Anti-HIV activity of harman, an anti-HIV principle from Symplocos setchuensis, and its derivatives

Matairesinol (1) and harman (5), identified from Symplocos setchuensis, were found to inhibit HIV replication in H9 lymphocyte cells. Anti-HIV evaluation of 28 derivatives of 5 revealed that compound 19 showed potent activity with EC(50) and therapeutic index values of 0.037 microM and 210, respectively.     

Customized ablation for asymmetrical corneal astigmatism

PURPOSE: To evaluate laser in situ keratomileusis (LASIK) cases in which a customized ablation assisted by corneal topography was performed. SETTING: Instituto de la Visión, Buenos Aires, Argentina. METHODS: The study group comprised 23 cases with asymmetrical corneas; 17 had myopia and 6, hyperopia. Visual acuity, spherical equivalent (SE), and cylinder vectorial change measurements, along with keratometry and corneal topography, were performed in all cases preoperatively and postoperatively. RESULTS: In the myopic cases, the mean preoperative SE was -4.92 diopters (D) +/- 2.46 (SD); it was -0.38 +/- 0.66 D after a mean follow-up of 4.41 +/- 2.32 months. In the hyperopic cases, the preoperative SE was +3.54 +/- 1.57 D; it was +0.33 +/- 0.50 D after a mean follow-up of 3.42 +/- 3.23 months. Cylinder vectorial change, visual acuity, and the number of visual acuity lines gained or lost were also evaluated in both groups. CONCLUSION: Although some features of our algorithm for corneal-topography-assisted customized ablations should be modified, the results of our treatment of cases with asymmetrical astigmatism were encouraging.     

Somatosensory evoked potentials in patients affected by unilateral cerebrovascular lesions with onset during the perinatal period or adulthood

Unilateral cerebrovascular lesions occurring during adulthood have been reported to be accompanied by high-amplitude somatosensory evoked potentials over the nonaffected hemisphere; however, the mechanisms by which somatosensory evoked potential amplitude increases over the nonaffected hemisphere are still unclear. To investigate the eventual presence of similar amplitude abnormalities in children, we recorded somatosensory evoked potentials in three groups of patients: one with unilateral cerebrovascular lesions that occurred during the perinatal period and another two with unilateral cerebrovascular lesions occurring during late adulthood or old age. Group 1 was comprised of 12 children and young adults (age range 2 3/12-31 years, 6 males and 6 females) who suffered from unilateral cerebrovascular lesion with perinatal onset. Four control groups were arranged with age matched to that of the patients. Adult patients were subdivided into two subgroups (group 2: n = 10, all males; group 3: n = 18, 12 males and 6 females) on the basis of the presence or absence of sensory impairment over the hemiplegic side. In group 1, the four youngest subjects, aged less than 6 years, were found to show somatosensory evoked potentials of abnormally high amplitude over the nonaffected hemisphere, with a "giant" main negative wave at around 45 ms (range 38.7-49.2), strictly localized over the central areas contralateral to the lesion; in normal controls, there was no such wave. All patients in group 2 were found to be affected by large infarctions in the territory of the middle cerebral artery, whereas patients in group 3 presented with subcortical lesions of the internal capsule isolated or in association with an involvement of the frontal and/or temporal cortex. Regarding somatosensory evoked potential parameters measured over the nonaffected hemisphere in adult/elderly subjects, a significant difference was observed for N20 and P22 latency, which was longer in both groups of patients than in controls. There is a significant difference in the neurophysiologic consequences of unilateral cerebrovascular lesion, as well as over the nonaffected hemisphere, if it occurs during early infancy or during adulthood. Our findings show a new type of "giant" somatosensory evoked potentials in some children affected by unilateral cerebrovascular lesion with perinatal onset.     

Prevention with clodronate of osteoporosis secondary to inhaled corticosteroid treatment in patients with chronic asthmatic bronchitis

Steroid therapy is the third most common cause of osteoporosis, after loss of gonad function and senescence. The aim of the present study was to evaluate the protective action of clodronate on bone mass loss induced by steroid therapy. Sixty patients with bronchial asthma receiving either fluticasone (250 mg x 4/day) or beclomethasone (250 mg x 4/day) inhaled corticosteroid treatment were enrolled. Half the patients received combination treatment with clodronate (100 mg i.m./14 days), for a total period of 12 months. All patients were evaluated at baseline and at the end of treatment for bone mineral density (BMD) and calcium/phosphor metabolism parameters (kalemia, kaluria, phosphoremia, phosphaturia, alkaline phosphatase and hydroxyprolinuria over a 24-h period). The results of this preliminary study confirm the protective influence of clodronate on bone mass loss, as documented by the increment in mean values in BMD reported at the end of treatment compared with baseline values.     

Nebivolol induces NO-mediated relaxations of rat small mesenteric but not of large elastic arteries

Nebivolol is a newer beta1-selective adrenergic receptor antagonist, which unlike classic beta-blockers, lowers systemic vascular resistance by direct vasodilator effects possibly involving NO. This study was designed to determine the effects of nebivolol on small arteries, which contribute to the most part of systemic vascular resistance. Mesenteric arteries, isolated from 9-week-old Wistar-Kyoto (WKY) rats, were studied under perfused and pressurized conditions using a video dimension analyzer. Aortic rings from the same animals were suspended in organ chambers, and isometric tension was measured. Experiments were performed during contraction to prostaglandin F2alpha. In small arteries, nebivolol (10(-9) to 3 x 10(-5) M) induced concentration-dependent relaxations (maximum, 55 +/- 8%). The relaxations were less pronounced as compared with those to acetylcholine (maximum, 99 +/- 2%; p < 0.05), but were significantly greater than those to atenolol (maximum, 2 +/- 0%; p < 0.05). Nebivolol-induced responses were markedly reduced by the NO-synthase inhibitor N(omega)-nitro-L-arginine methylester (L-NAME; 10(-4) M; maximum, 11 +/- 2%; p < 0.05). This inhibition could be entirely reversed by pretreatment with L-arginine (10(-3) M; maximum, 46 +/- 7%), a precursor of NO. In contrast to mesenteric arteries, nebivolol did not affect vascular tension of precontracted aortas. These findings indicate that nebivolol induces NO-mediated relaxations in small arteries but not large elastic vessels and therefore, independent of its antihypertensive action, might be effective in protecting the microcirculation in various cardiovascular disease states.     

Periampullary tumors

BACKGROUND: During the last 2 decades, endoscopic retrograde cholangiopancreatography (ERCP) has been widely used for the diagnosis of periampullary tumors and the preoperative or definitive treatment of jaundice. METHODS: We performed a retrospective analysis of 319 consecutive patients (184 men and 135 women with an average age of 66.5 years) who underwent ERCP for periampullary tumors between 1987 and 1999. RESULTS: Endoscopic internal biliary drainage was successful in 293 patients (92%), with some differences due to the origin of the tumor. There were five complications (1.5%), including four bleeds and one retroduodenal perforation. There were no deaths related to the endoscopic drainage. Eighty-four patients underwent pancreaticoduodenectomy. The postoperative morbidity rate was 23%, and the overall mortality rate was 4.8%. CONCLUSION: ERCP is a valid technique for the detailed preoperative assessment of periampullary tumors. It is also a safe method for internal biliary drainage.