Ultrastructural and biochemical characterization of glycosaminoglycans in HNK-1-positive large granular lymphocytes

Natural killer (NK) cells are large granular lymphocytes (LGLs) that contain distinct lysosomal granules. The present study was undertaken to determine if these lysosomes contain glycosaminoglycans (GAGs) similar to those previously described in myeloid cells. Mononuclear cells from human blood were stained with HNK-1 fluoresceinated monoclonal antibody, and the NK cell population reactive with this antibody were isolated with a fluorescence-activated cell sorter (FACS). Specific staining of sulfated macromolecules with the cationic reagent, high iron diamine, was observed in the lysosomal granules of 90% of the HNK-1 positive cells. Staining in the same location was also observed in the unsorted LGLs, presumed to be NK cells, and intense staining of the cell surface was also a prominent feature of these cells. Surface staining was not evident in the majority of the FACS- separated NK cells. Digestion with chondroitinase ABC or treatment with nitrous acid reduced the staining in both locations; after sequential treatment with both chondroitinase and nitrous acid, little or no staining was seen. The presence of chondroitin sulfate (and/or dermatan sulfate) and heparan sulfate was also shown by the finding that incubation of the isolated NK cells with 35S-sulfate yielded cell- associated radiolabeled macromolecules with the characteristics of these two groups of GAGs. Of the labeled GAG pool, 60% was degraded by chondroitinase and 40% was susceptible to nitrous acid treatment. LGLs of a patient with Chediak-Higashi syndrome was also stained, and intracellular sulfate staining was clearly localized to the enlarged granules, supporting the conclusion that the lysosomes are the major site of intracellular accumulation of GAGs in normal NK cells.     

Acute surgical removal of low-grade (Spetzler-Martin I-II) bleeding arteriovenous malformations

Background

Early surgical removal of cerebral AVMs is a relatively infrequent therapeutic option when dealing with a cerebral hemorrhage caused by AVM rupture: even in the case of low-grade AVMs, delayed treatment is, if possible, preferred because it is considered safer for patients and more comfortable for surgeons. To assess whether acute surgery may be a safe and effective management, we conducted a retrospective analysis of our early surgery strategy for ruptured low-grade AVMs.

Methods

We reviewed 27 patients with SM grade I-II AVM treated during 2004 to 2008 in the acute stage of bleeding (within the first 6 days after bleed). All patients showed a cerebral AVM on DSA at admission, and surgical removal was controlled by postoperative angiography. Neurological outcomes were assessed with GOS. The average length of follow-up was 22 months (48-3 months).

Results

Before surgery, 16 (59%) patients showed a GCS of 8 or less, 2 of them presenting an acute rebleeding after first hemorrhage. All patients underwent radical AVM surgical removal and hematoma evacuation in a single-stage procedure. Most patients (78%) were operated within the first day of hemorrhage. A favorable functional outcome (GOS: good recovery or moderate disability) was observed in 23 patients (85%). Mortality was 7.4%. Outcome was not significantly correlated with GCS at presentation and with presence of preoperative anisocoria.

Conclusions

Early surgery for grade I-II AVMs is a safe and definitive treatment, achieving both immediate cerebral decompression and patient protection against rebleeding, reducing time of hospital stay and allowing a more rapid rehabilitative course whenever necessary.     

A novel use of a split sheath to maintain vessel access when guidewire exchange is not possible

After inserting a catheter into a vessel, guidewire exchange technique must be used to maintain vascular access. If the lumen of the catheter is blocked and the guidewire exchange cannot be used, the catheter can only be removed, vascular access is lost, and an alternate vascular approach attempted. We describe a technique to remove the blocked catheter and still maintain vascular access. © 2008 Wiley‐Liss, Inc.     

The impact of health problems on depression and activities in middle-aged and older adults: age and social interactions as moderators

In this study, we compared the impact of health problems (HPs) on everyday activities and depressive symptoms between middle-aged and older adults. We also examined what type and source of social interactions moderate the noxious effects of HPs. Longitudinal analyses of data with 1,802 Japanese community-dwelling adults indicated that HPs were significantly related to (a) an increase in depressive symptoms among middle-aged adults and (b) a decline in everyday activities among older adults. The former was buffered by emotional family support, whereas the latter (b) was buffered by instrumental family support and, surprisingly, by negative interactions with family. In contrast, social interactions with other friends and acquaintances did not show any moderating effect.