Place of laparoscopic surgery in Crohn''s disease

PURPOSE: We describe our therapeutic strategy and correlate the anatomic results and clinical outcomes in patients who received immediate fibrinolytic therapy for thromboembolic complications occurring during endovascular treatment of an intracerebral aneurysm. METHODS: The medical records and angiographic examinations of 19 patients were reviewed. All endovascular procedures were performed with the patients under general anesthesia and fully heparinized. Thirteen patients received an intravenous bolus injection of aspirin. Thromboemboli occurred during catheterization or insertion of embolic material (Guglielmi detachable coils or mechanical detachable spirals) or in the first hours after the intervention. Clot distribution was within the MCA territory in 14 patients, the ACA in three patients, and the basilar trunk in two patients. A continuous intraarterial injection of urokinase was administered immediately, either superselectively distal to the thrombus or selectively within or closely proximal to the thrombus. In nine cases, chemical lysis was combined with mechanical clot fragmentation. Initial anatomic recanalization as well as clinical outcome at 3 months were evaluated. RESULTS: Ten patients showed complete recanalization and nine patients showed partial recanalization. Fourteen patients had a good clinical recovery. One patient was moderately disabled and two were severely disabled according to their scores on the Glasgow outcome scale. Two patients died, one as a consequence of the preexisting subarachnoid hemorrhage and the other because of a large intracerebral hematoma that developed after fibrinolysis. Of the 14 patients with a good clinical outcome, nine exhibited complete recanalization and five partial recanalization. CONCLUSION: Pharmacological thrombolysis seems to be a safe and efficient therapy that facilitates the natural fibrinolytic process, increasing the rate of recanalization in thromboembolic events. Clot fragmentation and superselective drug infusion appear to improve the rate of recanalization. Complete recanalization increases the chance of a better clinical outcome; however, clinical outcome does not always correspond to recanalization and vice versa.     

Distribution of HIV type 1 (HIV-1) in blood components: detection and significance of high levels of HIV-1 associated with platelets

BACKGROUND: Although inactivation of enveloped viruses transmitted by plasma derivatives has been successful, no methods for virus inactivation or removal have been established for platelet concentrates or red cell (RBC) components. Relatively little is known regarding the extent or significance of virus interactions with the cellular constituents in these components. STUDY DESIGN AND METHODS: Units of whole blood were collected from six HIV type 1 (HIV-1)-positive, asymptomatic individuals and separated into peripheral blood mononuclear cells (PBMNCs), cell-free plasma, white cell-reduced platelet concentrate, and white cell-reduced RBCs. DNA and RNA polymerase chain reaction and virus culture methods were used to study the compartmentalization of HIV-1 immediately after component preparation and after storage. RESULTS: As expected, HIV DNA and infectious virus were detected in fresh blood and in PBMNCs, and virion-associated RNA was detected in fresh plasma from all six donors. The levels of viral nucleic acids in these preparations remained relatively stable with 4 degrees C storage, whereas infectivity of PBMNCs was rapidly lost. Washed RBCs tested negative for HIV in all assays at all time points. Platelets retained high levels of HIV RNA (but not infectivity) after extensive washing, as well as after storage at 4 and 22 degrees C. High-level platelet-associated HIV-1 was also demonstrated in samples collected during early seroconversion. Periseroconversion and postseroconversion levels of platelet-associated HIV-1 correlated with the level of plasma viremia and with the rate of progression to AIDS. Cell-free virus from donor plasma and tissue culture fluid rapidly and firmly attached to platelets from noninfected donors. Infectivity of tissue culture virus bound to platelets was demonstrated in vitro. CONCLUSION: Significant levels of HIV-1 are associated with platelets during all stages of infection. Platelet-associated HIV could either mediate virus clearance or facilitate virus dissemination and expanded tropism. Finally, virus inactivation research must address virus associations with platelets.     

Rolandic type cerebral palsy in children as a pattern of hypoxic-ischemic injury in the full-term neonate

Magnetic resonance images (MRIs) of the brains of 11 patients aged from 1 week to 12 years with a distinctive type of cerebral palsy were selected based on distribution of cerebral lesions, which were restricted to bilateral perirolandic cortical and subcortical regions, including frequent symmetric involvement of basal ganglia and ventrolateral nucleus of thalami. Retrospectively, the perinatal history and clinical features were reviewed to correlate clinical data with this distinctive pattern of brain injury. Clinically affected neonates had an encephalopathy associated with a severe perinatal asphyxial event. Older children with cerebral palsy survived a similar perinatal course and demonstrated spastic quadriparesis with bulbar or pseudobulbar involvement, lack of verbal speech and variable delays in cognitive development. The distribution of hypoxic-ischemic lesions involving bilateral perirolandic regions, basal ganglia, and thalami, appears to correlate with increased metabolic areas of primary myelination in full-term neonates, but not with arterial border zones nor a single cerebral artery distribution. Myelination is a critical process in maturing brain associated with marked increase in tissue respiration and thus greater susceptibility to oxygen deprivation. It is believed that the extent of hypoxic-ischemic brain injury is determined principally by brain maturity and regional metabolic rates at time of insult and this correlates with active myelination in full-term neonates. This study confirms previous data from neuropathologic literature and recent reports of neuroimaging studies of asphyxiated neonates. In addition, retrospective analysis of the clinical data enables recognition of a type of cerebral palsy that might be the hallmark of hypoxic-ischemic injury in term neonates.     

Breast disease: dynamic spiral MR imaging

The cochleo- and tonotopic organization of the second auditory area (AII) was investigated in cats anaesthetized with pentobarbital using a combination of macro- and microelectrode recording technique. The results obtained following electrical stimulation of the neural fibres innervating different regions of the organ of Corti indicate the existence of two complete representations of the cochlea in area AII: one in the dorsocaudal portion, the other in its ventrorostral portion. These two cortical representations of the cochlea differ in size and spatial orientation. The dorsocaudal projection area extends over a distance of 2.6-3.2 mm from the basal to the apical focus and is arc-shaped. The spatial orientation of cochlea representation within the dorsocaudal region of AII is similar to that described in AI, in that stimulation of the cochlea base results in maximal responses in the more rostral portion of AII and stimulation of the apex evokes cortical responses more caudally. The ventrorostral region within AII is smaller (1.4-2.5 mm length), and has the opposite cochleotopic orientation (base and apex stimulation represented caudally and rostrally, respectively). In both AII zones, there was a proportionally greater cortical representation of basilar membrane than of middle and apical portions. Although two distinct zones with the overall cochleotopic pattern described above were noted in all cats, their precise size and location considerably varied in different animals. Using microelectrode recordings, a cortical tonotopic organization can be observed that was consistent with and expanded on the earlier cochleotopic data. Within the dorsocaudal region of AII, neurons with higher best frequency responses were located in more rostral regions, while those with lower best frequencies were located caudally. An orderly progression of best frequency responses was noted as serial recordings carried out along the full extent of the representation. Neurons within the ventrorostral region of AII also displayed an orderly progression of best frequencies, but in the opposite direction, with higher best frequencies noted more caudally and lower best frequencies more rostrally.     

Definition of natural T cell antigens with mimicry epitopes obtained from dedicated synthetic peptide libraries

Progress has recently been made in the use of synthetic peptide libraries for the identification of T cell-stimulating ligands. T cell epitopes identified from synthetic libraries are mimics of natural epitopes. Here we show how the mimicry epitopes obtained from synthetic peptide libraries enable unambiguous identification of natural T cell Ags. Synthetic peptide libraries were screened with Mycobacterium tuberculosis-reactive and -autoreactive T cell clones. In two cases, database homology searches with mimicry epitopes isolated from a dedicated synthetic peptide library allowed immediate identification of the natural antigenic protein. In two other cases, an amino acid pattern that reflected the epitope requirements of the T cell was determined by substitution and omission mixture analysis. Subsequently, the natural Ag was identified from databases using this refined pattern. This approach opens new perspectives for rapid and reliable Ag definition, representing a feasible alternative to the biochemical and genetic approaches described thus far.     

Confirmation of the human-pathogenic microsporidia Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Vittaforma corneae in water

Microsporidia, as a group, cause a wide range of infections, though two species of microsporidia in particular, Enterocytozoon bieneusi and Encephalitozoon intestinalis, are associated with gastrointestinal disease in humans. To date, the mode of transmission and environmental occurrence of microsporidia have not been elucidated due to lack of sensitive and specific screening methods. The present study was undertaken with recently developed methods to screen several significant water sources. Water concentrates were subjected to community DNA extraction followed by microsporidium-specific PCR amplification, PCR sequencing, and database homology comparison. A total of 14 water concentrates were screened; 7 of these contained human-pathogenic microsporidia. The presence of Encephalitozoon intestinalis was confirmed in tertiary sewage effluent, surface water, and groundwater; the presence of Enterocytozoon bieneusi was confirmed in surface water; and the presence of Vittaforma corneae was confirmed in tertiary effluent. Thus, this study represents the first confirmation, to the species level, of human-pathogenic microsporidia in water, indicating that these human-pathogenic microsporidia may be waterborne pathogens.     

Hepatobiliary and intestinal clearance of amphiphilic cationic drugs in mice in which both mdr1a and mdr1b genes have been disrupted

The triumph of antibiotics over bacterial pathogens that has occurred in the latter half of this century looks increasingly threatened as we approach the new millennium. Increasing resistance in important pathogens such as Mycobacterium tuberculosis, Shigella, and Streptococcus pneumoniae threatens the lives of millions. The increasing problems with drug resistance in (C. diphtheriae, Salmonella typhi and the pneumococcus in Vietnam are presented as examples of the challenge confronting tropical countries.     

Statistical modeling using preoperative prognostic variables in predicting extracapsular extension and progression after radical prostatectomy for prostate cancer

OBJECTIVE: To predict the risk of extracapsular extension and postoperative recurrence before radical prostatectomy (RP) for prostate cancer. METHODS: We performed multivariate Cox regression analysis on preoperative variables in 260 clinically localized prostate cancer patients who underwent RP. With these data, we constructed a relative risk of recurrence (Rr) equation and an equation to predict the probability of extracapsular extension (PECE) before RP. RESULTS: Rr is calculated as exp[(0.47 x race + 0.14 x PSAST) + (0.13 x worst biopsy Gleason sum) + (1.03 x stage T1c) + (1.55 x stage T2b,c)], where PSAST indicates a sigmoidal transformation of prostate-specific antigen. PECE is calculated as 1/[1 + exp(-Z)], where Z = -2.47 + 0.15 (PSAST) + 0.31 (worst biopsy Gleason sum) + 0.18 (race) + 0.16 (stage T1c) + 0.38 (stage T2b,c). CONCLUSION: These two equations can be used preoperatively to predict the probability of extracapsular disease and the risk of prostate-specific antigen recurrence in patients undergoing RP.