Mild cognitive impairment--beyond controversies, towards a consensus: report of the International Working Group on Mild Cognitive Impairment

The First Key Symposium was held in Stockholm, Sweden, 2-5 September 2003. The aim of the symposium was to integrate clinical and epidemiological perspectives on the topic of Mild Cognitive Impairment (MCI). A multidisciplinary, international group of experts discussed the current status and future directions of MCI, with regard to clinical presentation, cognitive and functional assessment, and the role of neuroimaging, biomarkers and genetics. Agreement on new perspectives, as well as recommendations for management and future research were discussed by the international working group. The specific recommendations for the general MCI criteria include the following: (i) the person is neither normal nor demented; (ii) there is evidence of cognitive deterioration shown by either objectively measured decline over time and/or subjective report of decline by self and/or informant in conjunction with objective cognitive deficits; and (iii) activities of daily living are preserved and complex instrumental functions are either intact or minimally impaired.

Predictors of progression from mild cognitive impairment to Alzheimer disease

OBJECTIVE

To determine the occurrence of neuropsychiatric symptomatology and the relation to future development of Alzheimer disease (AD) in persons with and without mild cognitive impairment (MCI).

METHOD

We followed 185 persons with no cognitive impairment and 47 with MCI (amnestic and multidomain), ages 75 to 95, from the population-based Kungsholmen Project, Stockholm, Sweden, for 3 years. Three types of neuropsychiatric symptoms were assessed at baseline: mood-related depressive symptoms, motivation-related depressive symptoms, and anxiety-related symptomatology. AD at 3-year follow-up was diagnosed according to Diagnostic and Statistical Manual for Mental Disorders-III-R criteria.

RESULTS

Psychiatric symptoms occurred more frequently in persons with MCI (36.2% mood, 36.2% motivation, and 46.8% anxiety symptoms) than in cognitively intact elderly individuals (18.4% mood, 13.0% motivation, and 24.9% anxiety). Of persons with both MCI and anxiety symptoms, 83.3% developed AD over follow-up vs 6.1% of cognitively intact persons and 40.9% persons who had MCI without anxiety. Among persons with MCI, the 3-year risk of progressing to AD almost doubled with each anxiety symptom (relative risk [RR] = 1.8 [1.2 to 2.7] per symptom). Conversely, among cognitively intact subjects, only symptoms of depressive mood were related to AD development (RR = 1.9 [1.0 to 3.6] per symptom).

CONCLUSIONS

The predictive validity of mild cognitive impairment (MCI) for identifying future Alzheimer disease (AD) cases is improved in the presence of anxiety symptoms. Mood-related depressive symptoms (dysphoria, suicidal ideation, etc.) in preclinical AD might be related to the neuropathologic mechanism, as they appear preclinically in persons both with and without MCI.

ADP is the cognate ligand for the orphan G protein-coupled receptor SP1999

P2Y receptors are a class of G protein-coupled receptors activated primarily by ATP, UTP, and UDP. Five mammalian P2Y receptors have been cloned so far including P2Y1, P2Y2, P2Y4, P2Y6, and P2Y11. P2Y1, P2Y2, and P2Y6 couple to the activation of phospholipase C, whereas P2Y4 and P2Y11 couple to the activation of both phospholipase C and the adenylyl cyclase pathways. Additional ADP receptors linked to Galpha(i) have been described but have not yet been cloned. SP1999 is an orphan G protein-coupled receptor, which is highly expressed in brain, spinal cord, and blood platelets. In the present study, we demonstrate that SP1999 is a Galpha(i)-coupled receptor that is potently activated by ADP. In an effort to identify ligands for SP1999, fractionated rat spinal cord extracts were assayed for Ca(2+) mobilization activity against Chinese hamster ovary cells transiently transfected with SP1999 and chimeric Galpha subunits (Galpha(q/i)). A substance that selectively activated SP1999-transfected cells was identified and purified through a series of chromatographic steps. Mass spectral analysis of the purified material definitively identified it as ADP. ADP was subsequently shown to inhibit forskolin-stimulated adenylyl cyclase activity through selective activation of SP1999 with an EC(50) of 60 nM. Other nucleotides were able to activate SP1999 with a rank order of potency 2-MeS-ATP = 2-MeS-ADP > ADP = adenosine 5'-O-2-(thio)diphosphate > 2-Cl-ATP > adenosine 5'-O-(thiotriphosphate). Thus, SP1999 is a novel, Galpha(i)-linked receptor for ADP.

Home telehealth for diabetes management: a systematic review and meta-analysis

AIM

It is estimated that more than 180 million people worldwide have diabetes. Health-care providers can remotely deliver health services to this patient population using information and communication technology, also known as home telehealth. Home telehealth may be classified into two subtypes: home telemonitoring (HTM) and telephone support (TS). The research objective was to systematically review the literature and perform meta-analyses to assess the potential benefits of home telehealth compared with usual care (UC) for patients with diabetes.

METHODS

An electronic literature search was conducted to identify studies on home telehealth and patients with diabetes that were published between 1998 and 2008 using Medline, Medline In-Process & Other Non-Indexed Citations, BIOSIS Previews and EMBASE.

RESULTS

Twenty-six studies (n = 5069 patients) on home telehealth for diabetes were selected. Twenty-one studies evaluated HTM and 5 randomized controlled trials assessed TS. HTM had a positive effect on glycaemic control [as measured by lower glycated haemoglobin level] compared with UC (weighted mean difference =-0.21; 95% confidence interval -0.35 to -0.08), but the results were mixed for TS. Study results indicated that home telehealth helps to reduce the number of patients hospitalized, hospitalizations and bed days of care. Home telehealth was similar or favourable to UC across studies for quality-of-life and patient satisfaction outcomes.

CONCLUSIONS

In general, home telehealth had a positive impact on the use of numerous health services and glycaemic control. More studies of higher methodological quality are required to give more precise insights into the potential clinical effectiveness of home telehealth interventions.

Repeatability and validity of an upper limb and neck discomfort questionnaire: the utility of the standardized Nordic questionnaire

The repeatability and validity of a questionnaire for upper limb and neck complaints were assessed in a population of 105 hospital outpatients with a range of upper limb and neck disorders (including cervical spondylosis, adhesive capsulitis, lateral epicondylitis, carpal tunnel syndrome and Raynaud's phenomenon). Subjects were asked to complete a modified Nordic-style upper limb and neck discomfort questionnaire on two occasions closely spaced in time. The repeatability of their responses was assessed by calculating a kappa coefficient (kappa), and the sensitivity and specificity of component items in the questionnaire were determined for specific diagnostic categories of upper limb and neck disorder. Symptom reports for pain in the upper limb and neck, pain interfering with physical activities, neurological symptoms and blanching were all found to be highly repeatable (kappa = 0.63-0.90). A number of regional pain reports proved to be very sensitive in relation to specific upper limb disorders, but, with the exception of reported finger blanching in patients with Raynaud's phenomenon, none proved to have a good specificity (range = 0.33-0.38). We conclude that a modified Nordic-style questionnaire is repeatable and sensitive, and is likely to have a high utility in screening and surveillance. However a complementary examination schedule of adequate specificity and repeatability is essential to establish a clinical diagnosis.

Individualized vaccination of AML patients in remission is associated with induction of antileukemia immunity and prolonged remissions

We developed a personalized cancer vaccine in which patient-derived acute myeloid leukemia (AML) cells are fused with autologous dendritic cells, generating a hybridoma that potently stimulates broad antitumor responses. We report results obtained from the first 17 AML patients, who achieved remission after chemotherapy and were then serially vaccinated to target minimal residual disease and prevent relapse. Vaccination was well tolerated and induced inflammatory responses at the site of administration, characterized by the dense infiltration of T cells. Vaccination was also associated with a marked rise in circulating T cells recognizing whole AML cells and leukemia-specific antigens that persisted for more than 6 months. Twelve of 17 vaccinated patients (71%; 90% confidence interval, 52 to 89%) remain alive without recurrence at a median follow-up of 57 months. The results demonstrate that personalized vaccination of AML patients in remission induces the expansion of leukemia-specific T cells and may be protective against disease relapse.

The role of transrectal ultrasound-guided biopsy-based staging, preoperative serum prostate-specific antigen, and biopsy Gleason score in prediction of final pathologic diagnosis in prostate cancer

OBJECTIVES

To evaluate the role of ultra sound-guided systematic and lesion-directed biopsies, biopsy gleason score, preoperative serum prostate-specific antigen (PSA) as three objective and reproducible variables to provide a reliable combination in preoperative identification of risk of extraprostatic extension in patients with clinically localized prostate cancer.

METHODS

The case records of 813 patients who underwent radical prostatectomy for clinically localized prostate cancer were analyzed. All had multiple systematic biopsies, two to three from each lobe, in addition to lesion-directed biopsies. Additionally, biopsies were done on seminal vesicles (SVs), if abnormal. Based on biopsy results, patients were classified as having stage B1 (T2a-T2b) or B2 (T2c) disease, depending on whether biopsies from one or both lobes were positive and stage C (T3) if there was evidence of SV involvement by biopsy of biopsies from areas of extracapsular extension as seen on transrectal ultrasound (TRUS) were positive. Logistic regression analyses with log likelihood chi-square test was used to define the correlation between individual as well as combination of preoperative variables and pathologic stage.

RESULTS

On final pathologic examination, 473 (58%) patients had organ-confined disease, 188 (23%) had extracapsular extension (ECE), with or without positive surgical margins, and 72 (9%) had SV involvement. Eighty (10%) patients had pelvic lymph node metastases. Biopsy-based staging was superior to clinical staging in predicting final pathologic diagnosis. Logistic regression analyses revealed that the combination of biopsy-based stage, preoperative serum PSA, and biopsy Gleason score provided the best prediction of final pathologic stage. Probability plots constructed with these data can provide significant information on risk of extraprostatic extension in individual patients.

CONCLUSIONS

This study demonstrates that TRUS-guided systematic biopsy in combination with preoperative serum PSA and biopsy Gleason score may provide a cost-effective approach for management decisions and prognostication in patients with prostate cancer.

Utilization of photon orbital angular momentum in the low-frequency radio domain

We show numerically that vector antenna arrays can generate radio beams that exhibit spin and orbital angular momentum characteristics similar to those of helical Laguerre-Gauss laser beams in paraxial optics. For low frequencies (< or = 1 GHz), digital techniques can be used to coherently measure the instantaneous, local field vectors and to manipulate them in software. This enables new types of experiments that go beyond what is possible in optics. It allows information-rich radio astronomy and paves the way for novel wireless communication concepts.

Functional gastrointestinal disorders: psychological, social, and somatic features

BACKGROUND

Psychological, social, and extraintestinal (somatic) disturbances are prominent features of functional gastrointestinal disorders (FGID); little attention, however, has been given to differences in the nature of these disturbances in the various FGID subgroups.

AIMS

(1) To determine whether psychological, social, and extraintestinal factors are associated with specific FGID, and/or with the overall severity and extent of FGID disturbance (the number of coexistent FGID subgroups present in any individual); and (2) to determine whether chronic social stressors link gastrointestinal, extraintestinal, and emotional symptomatologies in FGID.

PATIENTS

One hundred and eighty eight outpatients, fulfilling standard criteria for one or more functional gastroduodenal or functional bowel disorders.

METHODS

Utilising detailed and objective interview and questionnaire methods, detailed gastrointestinal, extraintestinal, psychological, and social data were collected.

RESULTS

Chronic stressors and extraintestinal and emotional symptomatologies were prominent features of functional dyspepsia (FD) and irritable bowel syndrome (IBS) alone. These particular features were, however, highly specific for particular FD and/or IBS subgroups. The chronic threat component of social stressors predicted the nature and extent of multisystem (gastrointestinal, extraintestinal, and emotional) symptomatology.

CONCLUSIONS

Notable differences between the various FGID subgroups support the symptom based classification of FGID. Chronic stressor provoked psychological and extraintestinal disturbance is most specific for the FD-IBS group of syndromes.

Circulating, but not local lung, IL-5 is required for the development of antigen-induced airways eosinophilia

IL-5 is induced locally in the lung and systemically in the circulation during allergic airways eosinophilic inflammation both in humans and experimental animals. However, the precise role of local and systemic IL-5 in the development of allergic airways eosinophilia remains to be elucidated. In our current study, we demonstrate that compared with their IL-5(+/+) counterparts, IL-5(-/-) mice lacked an IL-5 response both in the lung and peripheral blood, yet they released similar amounts of IL-4, eotaxin, and MIP-1alpha in the lung after ovalbumin (OVA) sensitization and challenge. At cellular levels, these mice failed to develop peripheral blood and airways eosinophilia while the responses of lymphocytes, neutrophils, and macrophages remained similar to those in IL-5(+/+) mice. To dissect the relative role of local and systemic IL-5 in this model, we constructed a gene transfer vector expressing murine IL-5. Intramuscular IL-5 gene transfer to OVA-sensitized IL-5(-/-) mice led to raised levels of IL-5 compartmentalized to the circulation and completely reconstituted airways eosinophilia upon OVA challenge, which was associated with reconstitution of eosinophilia in the bone marrow and peripheral blood. Significant airways eosinophilia was observed for at least 7 d in these mice. In contrast, intranasal IL-5 gene transfer, when rendered to give rise to a significant but compartmentalized level of transgene protein IL-5 in the lung, was unable to reconstitute airways eosinophilia in OVA-sensitized IL-5(-/-) mice upon OVA-challenge, which was associated with a lack of eosinophilic responses in bone marrow and peripheral blood. Our findings thus provide unequivocal evidence that circulating but not local lung IL-5 is critically required for the development of allergic airways eosinophilia. These findings also provide the rationale for developing strategies to target circulating IL-5 and/or its receptors in bone marrow to effectively control asthmatic airways eosinophilia.

The Southampton examination schedule for the diagnosis of musculoskeletal disorders of the upper limb

OBJECTIVES

Following a consensus statement from a multidisciplinary UK workshop, a structured examination schedule was developed for the diagnosis and classification of musculoskeletal disorders of the upper limb. The aim of this study was to test the repeatability and the validity of the newly developed schedule in a hospital setting.

METHOD

43 consecutive referrals to a soft tissue rheumatism clinic (group 1) and 45 subjects with one of a list of specific upper limb disorders (including shoulder capsulitis, rotator cuff tendinitis, lateral epicondylitis and tenosynovitis) (group 2), were recruited from hospital rheumatology and orthopaedic outpatient clinics. All 88 subjects were examined by a research nurse (blinded to diagnosis), and everyone from group 1 was independently examined by a rheumatologist. Between observer agreement was assessed among subjects from group 1 by calculating Cohen's kappa for dichotomous physical signs, and mean differences with limits of agreement for measured ranges of joint movement. To assess the validity of the examination, a pre-defined algorithm was applied to the nurse's examination findings in patients from both groups, and the sensitivity and specificity of the derived diagnoses were determined in comparison with the clinic's independent diagnosis as the reference standard.

RESULTS

The between observer repeatability of physical signs varied from good to excellent, with kappa coefficients of 0.66 to 1.00 for most categorical observations, and mean absolute differences of 1.4 degrees -11.9 degrees for measurements of shoulder movement. The sensitivity of the schedule in comparison with the reference standard varied between diagnoses from 58%-100%, while the specificities ranged from 84%-100%. The nurse and the clinic physician generally agreed in their diagnoses, but in the presence of shoulder capsulitis the nurse usually also diagnosed shoulder tendinitis, whereas the clinic physician did not.

CONCLUSION

The new examination protocol is repeatable and gives acceptable diagnostic accuracy in a hospital setting. Examination can feasibly be delegated to a trained nurse, and the protocol has the benefit of face and construct validity as well as consensus backing. Its performance in the community, where disease is less clear cut, merits separate evaluation, and further refinement is needed to discriminate between discrete pathologies at the shoulder.

Cytogenetic studies in rats of cyclohexylamine, a metabolite of cyclamate

Cyclohexylamine, the major known metabolite of cyclamate, was tested in vivo for possible cytogenetic effects. In rats injected with this metabolite, there was a direct relation between dose concentration and percentage of spermatogonial and bone marrow cells showing chromosomal breaks. Single chromatid breaks predominated with infrequent exchange figures.

The osteoporosis treatment gap in patients at risk of fracture in European primary care: a multi-country cross-sectional observational study

This study in 8 countries across Europe found that about 75% of elderly women seen in primary care who were at high risk of osteoporosis-related fractures were not receiving appropriate medication. Lack of osteoporosis diagnosis appeared to be an important contributing factor.

INTRODUCTION

Treatment rates in osteoporosis are documented to be low. We wished to assess the osteoporosis treatment gap in women ≥ 70 years in routine primary care across Europe.

METHODS

This cross-sectional observational study in 8 European countries collected data from women 70 years or older visiting their general practitioner. The primary outcome was treatment gap: the proportion who were not receiving any osteoporosis medication among those at increased risk of fragility fracture (using history of fracture, 10-year probability of fracture above country-specific Fracture Risk Assessment Tool [FRAX] thresholds, T-score ≤ - 2.5).

RESULTS

Median 10-year probability of fracture (without bone mineral density [BMD]) for the 3798 enrolled patients was 7.2% (hip) and 16.6% (major osteoporotic). Overall, 2077 women (55%) met one or more definitions for increased risk of fragility fracture: 1200 had a prior fracture, 1814 exceeded the FRAX threshold, and 318 had a T-score ≤ - 2.5 (only 944 received a dual-energy x-ray absorptiometry [DXA] scan). In those at increased fracture risk, the median 10-year probability of hip and major osteoporotic fracture was 11.2% and 22.8%, vs 4.1% and 11.5% in those deemed not at risk. An osteoporosis diagnosis was recorded in 804 patients (21.2%); most (79.7%) of these were at increased fracture risk. The treatment gap was 74.6%, varying from 53% in Ireland to 91% in Germany. Patients with an osteoporosis diagnosis were found to have a lower treatment gap than those without a diagnosis, with an absolute reduction of 63%.

CONCLUSIONS

There is a large treatment gap in women aged ≥ 70 years at increased risk of fragility fracture in routine primary care across Europe. The gap appears to be related to a low rate of osteoporosis diagnosis.

Utility of preoperative serum prostate-specific antigen concentration and biopsy Gleason score in predicting risk of pelvic lymph node metastases in prostate cancer

OBJECTIVES

To determine the accuracy of the preoperative serum concentration of prostate-specific antigen (PSA) plus the Gleason pathology score of biopsy specimens in predicting the presence of disease in the pelvic lymph nodes in patients with prostate cancer.

METHODS

The medical records of all patients treated for prostate cancer at eight medical centers from January 1988 to June 1993 were reviewed. There were 932 patients with newly diagnosed prostate cancer for whom all relevant data were available who had undergone pelvic lymphadenectomy with (n = 912) or without (n = 20) radical prostatectomy. The rate of false-negative predictions of metastases based on combined preoperative biopsy Gleason score and serum PSA concentration was analyzed. A multivariate logistic regression analysis was performed to assess the value of preoperative serum PSA and biopsy Gleason scores individually and in combination in predicting pelvic lymph node metastases.

RESULTS

The false-negative rate of metastases was 0% for preoperative PSA concentrations < or = 6 ng/mL and biopsy Gleason scores < or = 5 (n = 142) and 1.0% for PSA concentrations < or = 10 ng/mL and Gleason scores < or = 6 (n = 388). The 95% upper confidence limit for the rate of false negativity at this PSA cut-off level was 2.0%. A combination of preoperative serum PSA levels and biopsy Gleason scores provided the best prediction for the false-negative rates.

CONCLUSIONS

For patients with newly diagnosed prostate cancer who have biopsy Gleason scores < or = 6 and preoperative PSA concentrations < or = 10 ng/mL (42% of our series), a staging pelvic lymphadenectomy appears to be unnecessary. The substantial cost associated with both cross-sectional imaging and staging lymphadenectomy may therefore be avoidable in this group of patients.

Central vs. peripheral effects of estrogen on food intake and lipoprotein lipase activity in ovariectomized rats

The effects of implants of estradiol benzoate (EB) into either the ventromedial nucleus (VMH-EB) or the paraventricular nucleus (PVN-EB) of the hypothalamus were compared to the effects of peripheral EB (Per-EB) replacement in ovariectomized rats. After three days of hormone treatment, the Per-EB group and the PVN-EB group exhibited a decrease in food intake and body weight. Adipose tissue lipoprotein lipase activity was generally suppressed for the Per-EB, PVN-EB, and VMH-EB groups in the left and right parametrial and retroperitoneal fat pads. The finding that the VMH-EB and PVN-EB groups experienced similar peripheral stimulation but differed on the food intake and body weight measures would suggest that these measures are not entirely under peripheral control. The findings support the hypothesis that estrogen exerts its effects via multiple mechanisms, both central and peripheral. In addition, the PVN is shown to be an important site for further research on the modulation of feeding and metabolism by estrogen.

Occurrence of cognitive impairment and dementia in the community: a 9-year-long prospective study

OBJECTIVE

To determine incidence rates of non-dementia cognitive impairment, to examine the impact of attrition due to death on the observed incidence estimates, and to compare the observed and corrected estimates of non-dementia cognitive impairment with dementia incidence rates.

METHODS

A total of 1,435 persons without dementia aged 75+ from the Kungsholmen Project were evaluated for occurrence of dementia over 9 years. A total of 1,070 cognitively unimpaired subjects were also followed using amnestic mild cognitive impairment (aMCI) and other cognitive impairment, no dementia (OCIND) definitions. To correct the observed incidence rates for attrition due to death, cognitive status for subjects lost due to death was imputed using information on previous cognitive and health status. Observed and corrected incidence rates (IR) and 95% CIs were calculated with the person-years method, using Poisson distribution.

RESULTS

Incidence rates per 1,000 person-years were as follows: dementia IR = 70.4 (64.0 to 77.4); aMCI observed IR = 11.4 (8.6 to 15.1), corrected IR = 13.7 (10.3 to 18.2); OCIND observed IR = 33.8 (28.7 to 39.8), corrected IR = 42.1 (36.5 to 48.6). Both aMCI and OCIND incidence increased with advancing age. Observed incidence of aMCI and OCIND together was similar to that of dementia at age 75 to 79 but lower at more advanced ages. However, the cognitive impairment incidence after age 79 increased substantially when the estimates were corrected for attrition due to death during follow-up.

CONCLUSIONS

Non-dementia cognitive impairment is common and often underestimated in population studies that do not adjust for attrition.

Gene therapy with autologous, interleukin 2-secreting tumor cells in patients with malignant melanoma

We vaccinated metastatic melanoma patients with irradiated, autologous melanoma cells genetically engineered to secrete interleukin 2 (IL-2) to investigate whether an anti-tumor immune response would be induced. Melanoma cell cultures were established from surgical specimens and were engineered to secrete IL-2 by infection with recombinant retrovirus. Twelve patients were vaccinated subcutaneously one, two, or three times with approximately 10(7) irradiated, autologous, IL-2-secreting tumor cells. Treatment was well tolerated, with local reactions at 11 of 24 injection sites and minor systemic symptoms of fever and headache after 6 injections. One patient developed anti-tumor DTH after the first vaccination and showed an increased response after the second vaccination. Anti-autologous tumor CTLs could be detected prevaccination in the peripheral blood of seven patients and their activity increased after vaccination in four patients. No UICC-defined clinical responses were seen, but three patients had stable disease for 7-15 months, one of whom has not yet progressed (15+ months). Thus, patient vaccination with autologous, genetically engineered tumor cells is feasible and safe. Anti-tumor DTH and CTLs can be induced in some patients with such a vaccine.

Combined CXC chemokine and interleukin-12 gene transfer enhances antitumor immunity

It has been shown that intratumor administration of an adenovirus vector expressing IL-12 produces a potent T cell-mediated response that leads to significant tumor regression in a murine breast cancer model. IP-10 and MIG are CXC chemokines that recruit mononuclear cells in vivo. In addition to their chemotactic roles, IP-10 and MIG inhibit angiogenesis. We tested whether the addition of IP-10 or MIG may both enhance the antitumor immune response of IL-12 through T cell recruitment and inhibit tumor growth through angiostasis. Adenovirus vectors expressing IP-10 or MIG and/or IL-12 were administered intratumorally in a murine model of mammary adenocarcinoma and fibrosarcoma. Administration of IP-10 or MIG in combination with IL-12 resulted in considerable tumor regression and increased survival time of tumor-bearing animals as compared with IP-10, MIG, IL-12 alone or control-treated animals, with the IP-10 IL-12 combination being most effective. These results suggest augmenting the antitumor immune response and inhibiting tumor angiogenesis with adenoviral vectors expressing IP-10 in combination with IL-12 is a novel way to enhance tumor regression.

Dynamic analysis of immune and cancer cell interactions at single cell level in microfluidic droplets

Cell-cell communication mediates immune responses to physiological stimuli at local and systemic levels. Intercellular communication occurs via a direct contact between cells as well as by secretory contact-independent mechanisms. However, there are few existing methods that allow quantitative resolution of contact-dependent and independent cellular processes in a rapid, precisely controlled, and dynamic format. This study utilizes a high-throughput microfluidic droplet array platform to analyze cell-cell interaction and effector functions at single cell level. Controlled encapsulation of distinct heterotypic cell pairs was achieved in a single-step cell loading process. Dynamic analysis of dendritic cell (DC)-T cell interactions demonstrated marked heterogeneity in the type of contact and duration. Non-stimulated DCs and T cells interacted less frequently and more transiently while antigen and chemokine-loaded DCs and T cells depicted highly stable interactions in addition to transient and sequential contact. The effector function of CD8⁺ T cells was assessed via cytolysis of multiple myeloma cell line. Variable cell conjugation periods and killing time were detected irrespective of the activation of T cells, although activated T cells delivered significantly higher cytotoxicity. T cell alloreactivity against the target cells was partially mediated by secretion of interferon gamma, which was abrogated by the addition of a neutralizing antibody. These results suggest that the droplet array-based microfluidic platform is a powerful technique for dynamic phenotypic screening and potentially applicable for evaluation of novel cell-based immunotherapeutic agents.

The Relationship between Anaemia and Frailty: A Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

There is increasing evidence that frailty may play a role in chronic diseases, but the associations with specific chronic disorders are still unclear.

OBJECTIVES

To conduct a systematic review and meta-analysis assessing the association of anaemia and frailty in observational studies.

METHODS

The review was performed according to PRISMA guidelines. We searched PubMed, Web of Science, and Embase from 01/01/2002-10/09/2017. Pooled estimates were obtained through random effect models and Mantel-Haenszel weighting. Homogeneity was assessed with the I2 statistic. Publication bias was assessed with Egger's and Begg's tests.

RESULTS

Nineteen studies were included; two longitudinal, seventeen cross-sectional. All studies except three reported an association between anaemia and frailty. The pooled prevalence of prefrailty in individuals with anaemia was 49% (95% CI=38-59%; I2=89.96%) and 24% (95% CI=17-31%; I2= 94.78%) for frailty. Persons with anaemia had more than a twofold odds of frailty (pooled OR=2.24 95% CI=1.53-3.30; I2=91.8%). Only two studies longitudinally examined the association between anaemia and frailty, producing conflicting results.

CONCLUSIONS

Frailty and prefrailty are common in anaemic persons. Older persons with anaemia have more than a two-fold increased odds of frailty. These results may have clinical implications, as they identify the need to assess frailty in anaemic people and investigate any potential negative effects associated with the co-occurrence of both conditions. Longitudinal research that examines temporal changes in anaemia and effect of treatment are needed to further clarify the relationship between anaemia and frailty.

Isolation of a cell surface component of Helicobacter pylori that binds H type 2, Lewis(a), and Lewis(b) antigens

BACKGROUND & AIMS

Individuals of blood group O and nonsecretors of ABO blood group antigens are more susceptible to peptic ulcers. The aim of this study was to determine if blood group antigens associated with group O or secretor status are epithelial cell receptors for Helicobacter pylori.

METHODS

Bacterial binding and binding of monoclonal antibodies to H type 2, Lewis(a), and Lewis(b) to Kato III, buccal epithelial, and gastric mucosal cells were shown by flow cytometry. Bacterial outer membrane proteins eluted from H type 2, Lewis(a), or Lewis(b) were shown by polyacrylamide gel electrophoresis.

RESULTS

Kato III and human epithelial cells bound each monoclonal antibody; O cells bound more anti-H type 2 (P < 0.05). Binding indices for H. pylori correlated with those for anti-H type 2 (P < 0.005) and anti-Lewis(b) (P < 0.001) but not anti-Lewis(a). A 61-kilodalton protein was eluted from H type 2, Lewis(a), or Lewis(b).

CONCLUSIONS

Our results indicate that H type 2 is an important receptor for the 61-kilodalton bacterial adhesin, partly explaining increased susceptibility of individuals of blood group O to ulcers. Lewis(b) binds H. pylori more efficiently than Lewis(a). If these interactions occur in vivo, lack of Lewis(b) in mucosal fluids of nonsecretors may contribute to colonization by H. pylori.

Safety and immunogenicity of recombinant Bacille Calmette-Guérin (rBCG) expressing Borrelia burgdorferi outer surface protein A (OspA) lipoprotein in adult volunteers: a candidate Lyme disease vaccine

This phase I clinical trial was designed to determine the feasibility of using rBCG as a live bacterial vaccine vector for the outer surface protein A (OspA) of Borrelia burgdorferi and as model for other vaccines based on a rBCG vector. To construct the vaccine, a signal peptide derived from a mycobacterial lipoprotein was used to direct the export, and membrane-associated surface expression, of OspA in a standard strain of BCG (Connaught). The rBCG OspA vaccine was safe and immunogenic in several animal species, and protective in a mouse model of Lyme borreliosis. An intradermal injection (0.1 ml) of rBCG OspA was administered to 24 healthy adult volunteers sequentially at one of four dose levels, ranging from 2.0 x 10(4) CFU to 2 x 10(7) CFU, using a dose-escalation design. All volunteers were initially PPD-skin test and OspA antibody negative, and they were monitored for 2 years after immunization. Three volunteers had mild flu-like reactions 1-2 days after vaccination. Local ulceration and drainage at the site of injection, which occurred in 50% and 83% of volunteers in the two highest dose groups, persisted for 1-70 days before the ulcers healed. Most of the drainage samples yielded rBCG colonies that contained the OspA plasmid. Thirteen of 24 vaccinees, principally in the two highest dose groups, converted their PPD skin tests from negative to positive. None of the 24 volunteers developed OspA antibody. In conclusion, the current rBCG vaccine construct, the first such construct tested in humans, had a safety profile comparable to that of licensed BCG, but it did not elicit primary humoral responses to the vectored antigen.

A preliminary three-dimensional structure of angiogenin

A preliminary three-dimensional structure of angiogenin has been computed, based on its homology to bovine pancreatic ribonuclease A. A standard-geometry structure of ribonuclease was first obtained from its x-ray coordinates. The fit of the backbone of angiogenin to that of ribonuclease was then optimized by taking account of amino acid deletions and by minimizing its conformational energy-plus-a-penalty distance function constraining its backbone to that of ribonuclease. Side-chain and backbone dihedral angles were allowed to vary throughout the cycles of energy minimization. In the last stages of minimization, the penalty distance function was removed. A low-energy structure resembling ribonuclease was obtained.