Interleukin 21 and its receptor are involved in NK cell expansion and regulation of lymphocyte function

Cytokines are important in the regulation of haematopoiesis and immune responses, and can influence lymphocyte development. Here we have identified a class I cytokine receptor that is selectively expressed in lymphoid tissues and is capable of signal transduction. The full-length receptor was expressed in BaF3 cells, which created a functional assay for ligand detection and cloning. Conditioned media from activated human CD3+ T cells supported proliferation of the assay cell line. We constructed a complementary DNA expression library from activated human CD3+ T cells, and identified a cytokine with a four-helix-bundle structure using functional cloning. This cytokine is most closely related to IL2 and IL15, and has been designated IL21 with the receptor designated IL21 R. In vitro assays suggest that IL21 has a role in the proliferation and maturation of natural killer (NK) cell populations from bone marrow, in the proliferation of mature B-cell populations co-stimulated with anti-CD40, and in the proliferation of T cells co-stimulated with anti-CD3.

Cathepsin L: critical role in Ii degradation and CD4 T cell selection in the thymus

Degradation of invariant chain (Ii) is a critical step in major histocompatibility complex class II-restricted antigen presentation. Cathepsin L was found to be necessary for Ii degradation in cortical thymic epithelial cells (cTECs), but not in bone marrow (BM)-derived antigen-presenting cells (APCs). Consequently, positive selection of CD4+ T cells was reduced. Because different cysteine proteinases are responsible for specific Ii degradation steps in cTECs and BM-derived APCs, the proteolytic environment in cells mediating positive and negative selection may be distinct. The identification of a protease involved in class II presentation in a tissue-specific manner suggests a potential means of manipulating CD4+ T cell responsiveness in vivo.

T cell receptor delta gene mutant mice: independent generation of alpha beta T cells and programmed rearrangements of gamma delta TCR genes

T cells bearing T cell receptor (TCR) gamma and delta chain heterodimers are first generated early in ontogeny. They form distinct subsets that differ in their TCR repertoires and tissue distribution. Disruption of the mouse TCR C delta gene segment by a gene targeting method caused the complete loss of T cells bearing TCR gamma delta chains, but had little or no effect on the development of T cells bearing TCR alpha beta chains. The analyses of TCR gamma and delta genes in the mutant mice suggest that intracellular mechanisms acting at the level of DNA rearrangement play key roles in the differential gamma and delta gene rearrangements and in the generation of the highly restricted junctional sequences during fetal thymic development.

Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients

OBJECTIVE

To assess the validity of self-reported influenza and pneumococcal vaccination status.

DESIGN

Cross-sectional surveys of outpatients aged 65 years or older.

SETTING

A Veterans Affairs Medical Center (VA) and a community managed care organization (MCO). Both organizations have organized influenza and pneumococcal vaccination programs.

SUBJECTS

VA subjects included all elderly respondents to a mailed survey of 500 randomly selected outpatients. MCO subjects included all respondents to a telephone survey of 300 randomly selected elderly members of the MCO.

MEASUREMENTS

The VA survey was conducted following the 1995-1996 influenza season while the MCO survey was conducted following the 1994-1995 season. Self-report from the mailed survey for VA subjects and from the telephone survey for MCO subjects was compared to medical record documentation (paper and computerized combined).

RESULTS

The response rate was 77% (n = 369) for the VA subjects of whom 195 (53%) were aged 65 or older. The response rate for the MCO subjects was 84% (n = 237). Self-report of influenza vaccination had a sensitivity (SENS) of 1.0 and a specificity (SPEC) of .79 with a kappa of .72 (95% CI .58-.86) among VA patients. Among MCO patients, self-report of influenza vaccination had a SENS of .98 and a SPEC of .71 with kappa of .75 (95% CI .69-.89). Self-report of pneumococcal vaccination status among VA patients had a SENS of .97 and a SPEC of .53 with a kappa of .42 (95% CI .32-.52). Among MCO patients, self-report of pneumococcal vaccination had a SENS of .90 and a SPEC of .64 with a kappa of .54 (95% CI .40-.68). A secondary analysis excluding subjects living outside of the VA's catchment area improved the specificity and indices of concordance of self-report of both influenza and pneumococcal vaccination. A secondary analysis of MCO data which excluded subjects who received a pneumococcal vaccination > 2 years prior to the study also improved concordance and the negative predictive value of self-report.

CONCLUSIONS

Self-report of influenza vaccination is a highly sensitive and moderately specific measure. Self-report of pneumococcal vaccination is also a highly sensitive but less specific measure of vaccination status. Lower rates of validity for pneumococcal vaccination may reflect both less accurate recall, particularly for more distant vaccination, and less complete documentation in medical records.

Fall risk assessment measures: an analytic review

BACKGROUND

Clinicians are often unaware of the many existing scales for identifying fall risk and are uncertain about how to select an appropriate one. Our purpose was to summarize existing fall risk assessment scales to enable more informed choices regarding their use.

METHODS

After a systematic literature search, 21 articles published from 1984 through 2000 describing 20 fall risk assessments were reviewed independently for content and validation by a panel of five reviewers using a standardized review form. Fourteen were institution-focused nursing assessment scales, and six were functional assessment scales.

RESULTS

The majority of the scales were developed for elderly populations, mainly in hospital or nursing home settings. The patient characteristics assessed were quite similar across the nursing assessment forms. The time to complete the form varied from less than 1 minute to 80 minutes. For those scales with reported diagnostic accuracy, sensitivity varied from 43% to 100% (median = 80%), and specificity varied from 38% to 96% (median = 75%). Several scales with superior diagnostic characteristics were identified.

CONCLUSIONS

A substantial number of fall risk assessment tools are readily available and assess similar patient characteristics. Although their diagnostic accuracy and overall usefulness showed wide variability, there are several scales that can be used with confidence as part of an effective falls prevention program. Consequently, there should be little need for facilities to develop their own scales. To continue to develop fall risk assessments unique to individual facilities may be counterproductive because scores will not be comparable across facilities.

Relation between influenza vaccination and outpatient visits, hospitalization, and mortality in elderly persons with chronic lung disease

BACKGROUND

Influenza vaccine is underused in groups targeted for vaccination.

OBJECTIVE

To define the effects of influenza and the benefits of influenza vaccination in elderly persons with chronic lung disease.

DESIGN

Retrospective, multiseason cohort study.

SETTING

Large managed care organization.

PATIENTS

All elderly members of a managed care organization who had a previous diagnosis of chronic lung disease.

MEASUREMENTS

Outcomes in vaccinated and unvaccinated persons for the 1993-1994, 1994-1995, and 1995-1996 influenza seasons were compared after adjustment for baseline demographic and health characteristics. All data were obtained from administrative databases.

RESULTS

Vaccination rates were greater than 70% for each season. Among unvaccinated persons, hospitalization rates for pneumonia and influenza were twice as high in the influenza seasons as they were in the interim (noninfluenza) periods. Influenza vaccination was associated with fewer hospitalizations for pneumonia and influenza (adjusted risk ratio, 0.48 [95% CI, 0.28 to 0.82]) and with lower risk for death (adjusted odds ratio, 0.30 [CI, 0.21 to 0.43]) during the influenza seasons. It was also associated with fewer outpatient visits for pneumonia and influenza and for all respiratory conditions.

CONCLUSIONS

For elderly persons with chronic lung disease, influenza is associated with significant adverse health effects and influenza vaccination is associated with substantial health benefits, including fewer outpatient visits, fewer hospitalizations, and fewer deaths. Health care providers should take advantage of all opportunities to immunize these high-risk patients.

Binding of antidepressants to human brain receptors: focus on newer generation compounds

Using radioligand binding assays and post-mortem normal human brain tissue, we obtained equilibrium dissociation constants (Kds) for 17 antidepressants and two of their metabolites at histamine H1, muscarinic, alpha 1-adrenergic, alpha 2-adrenergic, dopamine D2, serotonin 5-HT1A, and serotonin 5-HT2 receptors. Several newer antidepressants were compared with older drugs. In addition, we studied some antimuscarinic, antiparkinson, antihistamine, and neuroleptic compounds at some of these receptors. For the antidepressants, classical tricyclic antidepressants were the most potent drugs at five of the seven receptors (all but alpha 2-adrenergic and 5-HT1A receptors). The chlorophenylpiperazine derivative antidepressants (etoperidone, nefazodone, trazodone) were the most potent antidepressants at alpha 2-adrenergic and 5-HT1A receptors. Of ten antihistamines tested, none was more potent than doxepin at histamine H1 receptors. At muscarinic receptors antidepressants and antihistamines had a range of potencies, which were mostly weaker than those for antimuscarinics. From the in vitro data, we expect adinazolam, bupropion, fluoxetine, sertraline, tomoxetine, and venlafaxine not to block any of these five receptors in vivo. An antidepressant's potency for blocking a specific receptor is predictive of certain side effects and drug-drug interactions. These studies can provide guidelines for the clinician in the choice of antidepressant.

The health and economic benefits associated with pneumococcal vaccination of elderly persons with chronic lung disease

BACKGROUND

More than 50% of the elderly population has not received pneumococcal vaccination. Uncertainty regarding the benefits of immunization, particularly for noninvasive disease, may contribute to the underuse of pneumococcal vaccine.

OBJECTIVE

To assess the health and economic benefits associated with pneumococcal vaccination.

METHODS

We conducted a 2-year retrospective cohort study among all elderly members of a staff-model managed care organization who had a baseline diagnosis of chronic lung disease. The study outcomes were assessed over 2 years, from November 15, 1993, through November 14, 1995, and included hospitalizations for pneumonia and influenza, death, and hospitalization costs. Using administrative data, we compared these outcomes for vaccinated and unvaccinated subjects using multivariate models to control for subjects' baseline demographic and health characteristics. The additive benefits of combined influenza and pneumococcal vaccination were also assessed for the 2 influenza seasons included in the study.

RESULTS

There were 1898 subjects. Pneumococcal vaccination was associated with significantly lower risks for pneumonia hospitalizations (adjusted risk ratio [RR], 0.57; 95% confidence interval [CI], 0.38-0.84; P=.005) and for death (adjusted RR, 0.71; 95% CI, 0.56-0.91; P = .008). For the control outcome of all nonpneumonia hospitalizations, rates did not differ significantly between the 2 groups (adjusted RR, 0.91; 95% CI, 0.77-1.07; P= .24). During the influenza seasons included in the study, the benefits of pneumococcal and influenza vaccinations were additive, with an adjusted RR of 0.28 (95% CI, 0.14-0.58; P<.001) for the number of hospitalizations for pneumonia and influenza among persons who had received both vaccinations compared with those who had received neither and an adjusted odds ratio of 0.18 (95% CI, 0.11-0.31; P<.001) for death. Over the 2-year outcome period, pneumococcal vaccination was also associated with direct medical care cost savings.

CONCLUSIONS

Pneumococcal vaccination of elderly persons with chronic lung disease was associated with fewer hospitalizations for pneumonia, fewer deaths, and direct medical care cost savings.

Determining global population distribution: methods, applications and data

Evaluating the total numbers of people at risk from infectious disease in the world requires not just tabular population data, but data that are spatially explicit and global in extent at a moderate resolution. This review describes the basic methods for constructing estimates of global population distribution with attention to recent advances in improving both spatial and temporal resolution. To evaluate the optimal resolution for the study of disease, the native resolution of the data inputs as well as that of the resulting outputs are discussed. Assumptions used to produce different population data sets are also described, with their implications for the study of infectious disease. Lastly, the application of these population data sets in studies to assess disease distribution and health impacts is reviewed. The data described in this review are distributed in the accompanying DVD.

Antagonism by neuroleptics of neurotransmitter receptors of normal human brain in vitro

Using radioligand binding techniques, we determined the equilibrium dissociation constants (KD's) for a series of neuroleptics at the dopamine (D-2), muscarinic, histamine H1, alpha 1- and alpha 2-adrenergic receptors of normal human brain tissue obtained at autopsy. Seventeen different compounds were studied at the D-2 receptor and 15 compounds at the remaining receptors. At the D-2 receptor of caudate nucleus, spiperone was the most potent compound (KD = 0.16 nM); clozapine the least potent (KD = 180 nM). The KD's for six compounds at the D-2 receptor of nucleus accumbens were not significantly different from their respective KD's in the caudate nucleus. The most potent and least potent compounds at the other receptors were clozapine and molindone at the muscarinic receptor, mesoridazine and molindone at the H1 receptor, spiperone and molindone at the alpha 1-receptor, and clozapine and haloperidol at the alpha 2-receptor, respectively.

Bedside cognitive screening instruments. A critical assessment

Bedside cognitive screening instruments are used increasingly in clinical and research settings to detect cognitive impairment and to quantify its severity. The authors review the five most frequently cited bedside screening tests that use an interview format and require brief administration times: the Mini-Mental State Examination, the Cognitive Capacity Screening Examination, Mattis Dementia Rating Scale, Kahn's Mental Status Questionnaire, and the Short Portable Mental Status Questionnaire. The tests all have adequate inter-rater reliability, and adequate test-retest reliability has been established for three of the tests. All of the tests show close correspondence with clinical diagnoses of delirium and dementia and are useful for the diagnosis and quantification of these syndromes. However, there is currently no evidence that the tests increase the level of diagnostic accuracy achieved through clinical examination alone. All of the tests have substantial false-negative rates, with false-negative errors frequent among patients with focal lesions, particularly of the right hemisphere. False-positive errors may be more common among patients with less education and lower socioeconomic status. The tests reviewed do not detect many types of cognitive deficit that may bear critically on differential diagnosis and case management. Suggestions are given for further research on the current measures and for the development of new screening tests that would meet a broader range of clinical purposes.

Genital papillomavirus infection and cervical dysplasia--opportunistic complications of HIV infection

Certain human genital papillomaviruses (HPV) are strongly associated with cervical dysplasia and cancer. Evidence is accumulating that HPV infection and ano-genital cancers are more common in patients with the acquired immunodeficiency syndrome. The objective of our study was to evaluate the extent to which HPV infection and associated cervical disease constitute opportunistic complications of human immunodeficiency virus (HIV) infection in a population of sexually promiscuous, HIV-infected women in Kinshasa, Zaire. In 1989 we obtained Pap smears and cervicovaginal lavage specimens for HPV DNA testing from 47 HIV-seropositive and 48 HIV-seronegative prostitutes who were part of a cohort under observation since 1988. Thirty-eight percent of the HIV-seropositive and 8% of the seronegative women (odds ratio = 6.8; p = 0.001) had HPV DNA detected by either ViraType, a dot-blot assay which detects specific genital HPV types, or low-stringency Southern blot, which detects all HPV types. Eighty-two women (86%) had an interpretable Pap smear; 11 of 41 (27%) HIV-seropositive women and one of 41 (3%) seronegative women had cervical intra-epithelial neoplasia (CIN) (odds ratio = 14.7; p = 0.002). HIV seropositivity, HPV infection and CIN were highly associated. Eight (73%) of 11 seropositive women with CIN had HPV detected. Both HPV infection and cervical cancer may emerge as opportunistic complications of HIV infection in populations in which HIV, HPV and cervical cancer are common.

Recovery of spatial learning by grafts of a conditionally immortalized hippocampal neuroepithelial cell line into the ischaemia-lesioned hippocampus

Transient global cerebral ischaemia in rats causes relatively circumscribed and specific damage to the CA1 pyramidal cells of the dorsal hippocampus, along with a cognitive deficit manifest as difficulties in the performance of a range of spatial learning and memory tasks. Our previous studies have shown that restoration of behavioural performance in ischaemic rats by neural grafts taken relatively late in fetal development occurs only after local replacement of cells homotypic to those lost through the ischaemic insult. This lesion-plus-behaviour model therefore offers a powerful means for establishing whether multipotent embryonic neuroepithelial cells will engraft the damaged CA1, develop into appropriate neuronal phenotypes and produce behavioural recovery. Here we report that, in rats subjected to 15 min of global cerebral ischaemia, intrahippocampal implants of a conditionally immortal, multipotent cell line, directly derived from the embryonic day 14 hippocampal neuroepithelium of the H-2Kb-tsA58 transgenic mouse, selectively repopulated the lesioned CA1 pyramidal layer and restored ischaemia-induced deficits in acquisition of a hidden platform location in the Morris water maze.

The preterm gut microbiota: changes associated with necrotizing enterocolitis and infection

AIM

To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS).

METHODS

Ninety-nine stools from 38 infants of median 27-week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities.

RESULTS

Standard microbiological culture identified a mean of two organisms (range 0-7), DGGE 12 (range 3-18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively.

CONCLUSIONS

Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.

Performance of the ATLAS trigger system in 2015

During 2015 the ATLAS experiment recorded [Formula: see text] of proton-proton collision data at a centre-of-mass energy of [Formula: see text]. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton-proton collision data.

The impacts of COVID-19 pandemic on marine litter pollution along the Kenyan Coast: A synthesis after 100 days following the first reported case in Kenya

The contribution of COVID-19 pandemic to marine litter pollution was studied in Mombasa, Kilifi, and Kwale counties of Kenya, in June 2020 (100 days following the first confirmed case in Kenya). Standing stock surveys were conducted in 14 streets and 21 beaches while 157 transects were surveyed for floating litter. COVID-19 related items contributed up to 16.5% of the total litter encountered along the streets. The urban beaches (Mkomani and Nyali) had the highest quantities of COVID-19 related items (55.1% and 2.6% respectively) attributable to the ability to purchase single-use products and lifestyle. Most of the recreational beaches had no COVID-19 related products which could be attributed to the presidential directive on beach closure as a COVID-19 contingency measure. No COVID-19 related litter was found in the floating litter. Generally, beach closure and cessation of movement reduced the amount of litter that leaked to the marine environment.

HIV and other sexually transmitted diseases among female prostitutes in Kinshasa

In 1988, 1233 prostitutes from different geographic areas of Kinshasa participated in a cross-sectional survey on HIV infection and other sexually transmitted diseases (STDs). Despite relatively good knowledge about AIDS and STDs, the reported preventive behaviour was poor. Only 12% of the women reported regular use of condoms, while greater than 50% of the women reported regular use of antibiotics and 38% reported doing nothing specific to prevent STDs. Thirty-five per cent of the women were HIV-positive compared with 27% in a similar survey in Kinshasa in 1986. The prevalence of other STDs was very high, ranging from 5% for genital ulcer disease (GUD) to 23% for gonococcal infection. HIV-positive women were older than HIV-negative women (26.9 versus 25.4 years; P less than 0.001), had a significantly lower level of reported condom use (9 versus 14%, P = 0.009), and reported more frequent use of antibiotics to prevent STDs (55 versus 42%, P = less than 0.001). The prevalence of syphilis, gonorrhoea, chlamydial infection and trichomoniasis was not higher in HIV-positive women compared with HIV-negative women. However, HIV-positive women had a higher prevalence of GUD (9 versus 3%, P less than 0.001), antibodies against Haemophilus ducreyi (82 versus 57%, P less than 0.001), antibodies against herpes simplex virus type 2 (96 versus 76%, P less than 0.001), condylomata accuminata (5 versus 1%, P = 0.003) and cytologic evidence of human papilloma virus on Papaniclaou cervical smear (11 versus 5%, P = 0.006). This study confirms the high incidence of HIV and other STDs among prostitutes in Africa.(ABSTRACT TRUNCATED AT 250 WORDS)