Sulfation of L-selectin ligands by an HEV-restricted sulfotransferase regulates lymphocyte homing to lymph nodes

Lymphocytes home to lymph nodes, using L-selectin to bind specific ligands on high endothelial venules (HEV). In vitro studies implicate GlcNAc-6-sulfate as an essential posttranslational modification for ligand activity. Here, we show that genetic deletion of HEC-GlcNAc6ST, a sulfotransferase that is highly restricted to HEV, results in the loss of the binding of recombinant L-selectin to the luminal aspect of HEV, elimination of lymphocyte binding in vitro, and markedly reduced in vivo homing. Reactivity with MECA 79, an adhesion-blocking mAb that stains HEV in lymph nodes and vessels in chronic inflammatory sites, is also lost from the luminal aspects of HEV. These results establish a critical role for HEC-GlcNAc6ST in lymphocyte trafficking and suggest it as an important therapeutic target.     

Embryonic development of four different subsets of cholinergic neurons in rat cervical spinal cord

The developmental stage at which a neuron becomes committed to a neurotransmitter phenotype is an important time in its ontogenetic history. The present study examines when choline acetyltransferase (ChAT) is first detected within each of four different subsets of cholinergic neurons previously identified in the cervical enlargement of the spinal cord: namely, motor neurons, partition cells, central canal cluster cells, and dorsal horn neurons. By examining the temporal sequence of embryonic development of these cholinergic neurons, we can infer the relationships between ChAT expression and other important developmental events. ChAT was first detected reliably on embryonic day 13 (E13) by both biochemical and immunocytochemical methods, and it was localized predominantly within motor neurons. A second group of primitive-appearing ChAT-positive cells was detected adjacent to the ventricular zone on E14. These neurons seemed to disperse laterally into the intermediate zone by E15, and, on the basis of their location, were tentatively identified as partition cells. A third group of primitive ChAT-immunoreactive cells was detected on E16, both within and around the ventral half of the ventricular zone. By E17, some members of this "U"-shaped group appeared to have dispersed dorsally and laterally, probably giving rise to dorsal horn neurons as well as dorsal central canal cluster cells. Other members of this group remained near the ventral ventricular zone, most likely differentiating into ventral central canal cluster cells. Combined findings from the present study and a previous investigation of neurogenesis (Phelps et al.: J. Comp. Neurol. 273:459-472, '88), suggest that premitotic precursor cells have not yet acquired the cholinergic phenotype because ChAT is not detectable until after the onset of neuronal generation for each of the respective subsets of cholinergic neurons. However, ChAT is expressed in primitive bipolar neurons located within or adjacent to the germinal epithelium. Transitional stages of embryonic development suggest that these primitive ChAT-positive cells migrate to different locations within the intermediate zone to differentiate into the various subsets of mature cholinergic neurons. Therefore, it seems likely that spinal cholinergic neurons are committed to the cholinergic phenotype at pre- or early migratory stages of their development. Our results also hint that the subsets of cholinergic cells may follow different migration routes. For example, presumptive partition cells may use radial glial processes for guidance, whereas dorsal horn neurons may migrate along nerve fibers of the commissural pathway. Cell-cell interactions along such diverse migratory pathways could play a role in determining the different morphological, and presumably functional, phenotypes expressed by spinal cholinergic neurons.     

Soft lens lubricants and prelens tear film stability

Soft contact lens wearers complaining of "dry eye" are frequently prescribed rewetting drops, although the mode of action and efficacy of this treatment have not been established. Enhancement of prelens tear film (PLTF) stability could provide a basis for symptomatic relief with solution instillation. Thirty symptomatic hydroxyethyl methacrylate (HEMA) lens wearers participated in 4 separate trials of no solution (baseline), saline, and 2 soft lens lubricants. Solutions were applied for a 6-h adaptation period, and PLTF noninvasive break-up time (NIBUT) was monitored for 1 h after a final instillation. PLTF NIBUT was significantly elevated 1 min after instillation of all solutions (p less than 0.001, logrank test) but this effect persisted for less than 5 min. The transient enhancement of PLTF stability arising from the instillation of these rewetting solutions is unlikely to provide a basis for prolonged symptomatic relief.     

A pharmacoeconomic comparison of antithymocyte globulin and muromonab CD3 induction therapy in renal transplant recipients

Antithymocyte globulin (ATG) and muromonab CD3 (OKT3) are currently the only antilymphocyte preparations that are commercially available for induction immunosuppressive therapy for renal allograft transplantation in the US. ATG, in the usually prescribed doses, is more expensive than muromonab CD3, but muromonab CD3 is associated with more severe adverse effects that may affect clinical outcome and overall cost. We performed a retrospective study of all adult recipients of a first cadaveric renal allograft, who underwent transplantation between January 1991 and December 1994 who received either ATG (n = 92) or muromonab CD3 (n = 91) for induction therapy at our transplant centre. The average age of recipients was older (50 vs 44 yrs; p = 0.001) and extended donors were more commonly used in the ATG group (41 vs 13%; p = 0.0001) compared with the muromonab CD3 group. Nevertheless, at 1 year post-transplant, the incidence of rejection was lower (34 vs 47%) and graft survival was better (93 vs 85%; p = 0.03) in the ATG group. Patients who received ATG were discharged earlier (9.4 vs 13.3 days; p = 0.0001) and had similar serum creatinine levels on the day of discharge (2.4 +/- 1.5 vs 2.1 +/- 1.1 mg/dl; p = 0.25). Overall, the 1-year hospitalisation costs of transplantation and readmissions were similar [$US39,937 +/- 17,014 vs $US42,850 +/- 20,923 (currency year 1994); p = 0.22]. This is the first comparison of ATG and muromonab CD3 in renal transplant recipients to consider clinical as well as economic outcomes. For renal transplant patients in whom induction therapy is used at our centre, the initial expense of ATG can be justified by improved graft survival, fewer rejection episodes, and shorter hospital stays, which are associated with similar overall transplantation costs.     

Assessing and planning home-based care for persons with AIDS

The HIV/AIDS pandemic continues to gather momentum in many developing countries, increasing the already heavy burden on health care facilities. As a result, donors, implementing partners and communities are beginning to create home-based care programmes to provide care for persons with HIV/AIDS. This paper recommends reorienting this home care provision as a service founded in, and coming from, the community rather than the health system. A methodology, in the form of an assessment matrix, is provided to facilitate the assessment of a community's capacity to provide care for people with AIDS. The focus is on rapid assessment methods using, where possible, readily available information to clearly and systematically define current circumstances. The matrix created for a specific community is then used in the development of an action plan with interventions prioritized and tailored to local needs. A case study from a hypothetical developing country, where HIV/AIDS is a significant problem, is used to illustrate the process.     

The Health Security Act and improving the quality of care: will the Clinton reforms help or hinder?

Maintaining and improving the quality of care is central to the Health Security Act, according to this in-depth analysis of the Act's intended quality reforms. The author reviews the proposal from several perspectives, including those of administrative law, hospital administration, health services research, and risk management. In the author's opinion, quality reforms involving the federal government as purchaser of medical care and as grader of the quality of its health care providers require close scrutiny. The establishment of a National Health Board and a National Quality Management Council further heightens concerns for quality standards and oversight. The article also evaluates the proposed health quality data super-highway, making several stops for contemplation and critical analysis.     

Variation in dental service provision among adult migrant public-funded patients

OBJECTIVE: To examine type of care, oral health status and service patterns by country of birth and language. METHODS: A random sample of public-funded patients (n = 6, 109) was surveyed in 1995-96. RESULTS: Emergency care was highest among overseas-born patients who spoke a non-English language at home; edentulism was highest among Australian-born/English only patients; while a higher percentage of Australian-born persons were in the periodontal health category (chi 2; p < 0.05). Differences in caries experience were generally small (ANOVA; p < 0.05). Service provision varied by country of birth/language after controlling for socio-demographic characteristics, type of care, and oral health status in six service areas (logistic regression; p < 0.05). CONCLUSIONS: Service patterns may reflect behavioural and cultural factors of patients or providers operating independently of socio-demographic and oral health status variables. IMPLICATIONS: Variation and potential inequality in service patterns related to cultural factors existed within a group of disadvantaged patients.     

Pathologic features of prognostic significance for adrenocortical carcinoma after curative resection

OBJECTIVE: To identify the pathologic features of prognostic significance in patients with resectable adrenocortical carcinomas. DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Review of the Memorial Sloan-Kettering Cancer Center prospective adrenocortical carcinoma database from 1986 through 1996 identified 46 patients who underwent curative adrenalectomy for primary disease. All cases were reviewed by a single pathologist and each primary tumor was characterized by 16 separate pathologic parameters. MAIN OUTCOME MEASURE: Overall survival rates in the patient population. RESULTS: The 5-year overall survival rate for the entire cohort was 36% (median survival rate, 28 months). Of the pathologic factors analyzed, tumor size, number of mitotic figures, and the presence of intratumoral hemorrhage were independent prognostic factors. Patients presenting with primary tumors larger than 12 cm (n = 30) had a worse outcome compared with those with smaller tumors (n = 16) (5-year survival rate: 53% vs. 22%, P<.05). Mitotic count (> or =6 per 10 high-power fields) was a negative prognostic feature (n = 15) with a 5-year survival rate of 13% vs. 51% for 0 to 6 mitotic figures per 10 highpower fields (n = 31, P<.05). Intratumoral hemorrhage (n = 23) was also a negative prognostic factor compared with no evidence of intratumoral hemorrhage (n = 23) (5-year survival rate, 53% vs. 22%, P<.05). Overall survival rates were also calculated based on the number of pathologic risk factors. Patients with no risk factors had an 83% 5-year survival rate, which decreased to 42% with 1 factor, 33% with 2 factors, and 0% with all 3 risk factors. CONCLUSIONS: Tumor size, hemorrhage, and mitotic count correlate with survival rates for patients undergoing curative resection. Based on these pathologic factors, adrenocortical carcinomas may be divided into low- and high-risk groups.