Brief report: Risk factors for pneumococcal vaccine refusal in adults

Background: Invasive pneumococcal disease is a significant cause of morbidity and mortality in the United States. Despite availability of an effective vaccine, many patients refuse vaccination.
Objective: To investigate patient characteristics and features of the patient–provider relationship associated with pneumococcal vaccine refusal.
Design: Case–control study using chart review.
Patients: Five hundred adults from the medical clinics of a 1,000-bed inner-city teaching hospital.
Measurements and Main Results: Independent risk factors for pneumococcal vaccine refusal included patient–provider gender discordance (odds ratio (OR)=2.09, 95% confidence interval (CI) 1.07 to 4.09); a visit to a not-usual provider at the time of vaccine offering (OR=2.26, 95% CI 1.13 to 4.49); never having received influenza vaccination (OR=7.44, 95% CI 3.76 to 14.76); prior pneumococcal vaccine refusals (OR=3.45, 95% CI 1.60 to 7.43); and a history of ever having refused health maintenance tests (OR=2.86, 95% CI 1.40 to 5.84).
Conclusions: We have identified both patient factors and factors related to the patient–provider relationship that are risk factors for pneumococcal vaccine refusal. By identifying patients at risk for pneumococcal vaccine refusal, efforts to increase vaccination rates can be better targeted.     

Nonadherence to antihypertensive medications amongst patients with uncontrolled hypertension: A retrospective study

Medication nonadherence represents a modifiable risk factor for patients with hypertension. Identification of nonadherent patients could have significant clinical and economic implications in the management of uncontrolled hypertension.We analysed the results of 174 urinary adherence screens from patients referred to Addenbrooke''s Hospital, Cambridge, for uncontrolled hypertension. Cases were identified for evaluation by results of liquid chromatography-tandem mass spectrometry of urine samples (males: 91; females: 83; age range: 17–87). We performed a binary logistic regression analysis for nonadherence using age, sex, and number of medications prescribed (both antihypertensives and non-antihypertensives separately) as independent predictors. Rates of nonadherence for individual antihypertensive drugs were calculated if prescribed to ≥10 patients.The overall rate of nonadherence to one or more prescribed antihypertensive medications was 40.3%. 14.4% of all patients were nonadherent to all prescribed antihypertensive medications (complete nonadherence), whereas 25.9% of all patients were nonadherent to at least 1, (but not all) prescribed antihypertensive medications (partial nonadherence). 72% of patients were prescribed ≥3 antihypertensives And for every increase in the number of antihypertensive medications prescribed, nonadherence increased with adjusted odds ratios of 2.9 (P < .001). Logistic regression showed that women were 3.3 times more likely to be nonadherent (P = .004). Polypharmacy (≥6 medications prescribed for hypertension and/or concomitant comorbidities) was prevalent in 52%. Bendroflumethiazide and chlortalidone demonstrated the highest and lowest nonadherences respectively (45.5% and 11.8%).Rate of nonadherence in patients with hypertension was significantly impacted by sex and number of antihypertensive medications prescribed. Understanding these factors is crucial in identifying and managing nonadherence.     

Safety and Biocompatibility of Carbohydrate-Functionalized Polyanhydride Nanoparticles

Carbohydrate functionalization of nanoparticles allows for targeting of C-type lectin receptors. This family of pattern recognition receptors expressed on innate immune cells, such as macrophages and dendritic cells, can be used to modulate immune responses. In this work, the in vivo safety profile of carbohydrate-functionalized polyanhydride nanoparticles was analyzed following parenteral and intranasal administration in mice. Polyanhydride nanoparticles based on 1,6-bis-(p-carboxyphenoxy)hexane and 1,8-bis-(p-carboxyphenoxy)-3,6-dioxaoctane were used. Nanoparticle functionalization with di-mannose (specifically carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside), galactose (specifically carboxymethyl-β-galactoside), or glycolic acid induced no adverse effects after administration based on histopathological evaluation of liver, kidneys, and lungs. Regardless of the polymer formulation, there was no evidence of hepatic or renal damage or dysfunction observed in serum or urine samples. The histological profile of cellular infiltration and the cellular distribution and kinetics in the lungs of mice administered with nanoparticle treatments followed similar behavior as that observed in the lungs of animals administered with saline. Cytokine and chemokine profiles in bronchoalveolar lavage fluid indicated surface chemistry dependence on modest secretion of IL-6, IP-10, and MCP-1; however, there was no evidence of any deleterious histopathological changes. Based on these analyses, carbohydrate-functionalized nanoparticles are safe for in vivo applications. These results provide foundational information towards the evaluation of the capabilities of these surface-modified nanoparticles as vaccine delivery formulations.KEY WORDS: biocompatibility, carbohydrate, nanoparticles, polyanhydride, safety     

Identification of parameters required for efficient lentiviral vector transduction and engraftment of human cord blood CD34(+) NOD/SCID-repopulating cells

OBJECTIVE: Human cord blood (CB) is a potential source of hematopoietic stem cells (HSC) for gene therapy to treat patients with hematopoietic disorders. However, limited numbers of CB CD34(+) cells, low transduction efficiency with lentiviral vectors (LVs), and low engraftment efficiency of nonobese diabetic/severe combined immunodeficient (NOD/SCID) repopulating cells (SRC), a measure of HSC, are blocks to this procedure. To optimize culture and transduction conditions, we compared various lengths of time for prestimulation before transduction, transduction duration, and posttransduction cell culture. MATERIALS AND METHODS: We used a LV to transduce human CB CD34(+) cells followed by engraftment into NOD/SCID mice. We evaluated the effects of prestimulation and transduction time and optimized ex vivo cell culture duration before transplantation. RESULTS: We were able to achieve up to 40% transduction efficiency and up to 50% engraftment efficiency of SRC in CB CD34(+) cells when CB CD34(+) cells were either not prestimulated or prestimulated in 1% fetal bovine serum medium for 1 hour, followed by 5 hours transduction and 3 days culture in a cocktail of growth factors after transduction. No apparent functional changes of CB CD34(+) cells were noted under these conditions. CONCLUSION: This gene-transduction/cell-expansion protocol is the first systematic study to optimize prestimulation time, transduction time, and, very importantly, ex vivo culture time after transduction, and may be of use for LV gene transduction in a gene therapy setting.     

Activation of the sodium pump blocks the growth hormone-induced increase in cytosolic free calcium in rat adipocytes

GH promptly increases cytosolic free calcium ([Ca2+]i) in freshly isolated rat adipocytes. Adipocytes deprived of GH for 3 h or longer are incapable of increasing [Ca2+]i in response to GH, but instead respond in an insulin-like manner. Insulin blocks the GH-induced increase in [Ca2+]i in GH-replete cells and stimulates the sodium pump (i.e. Na+/K+-ATPase), thereby hyperpolarizing the cell membrane. Blockade of the Na+/K+-ATPase with 100 microM ouabain reversed these effects of insulin and enabled GH to increase [Ca2+]i in GH-deprived adipocytes. Both insulin and GH activated the sodium pump in GH-deprived adipocytes, as indicated by increased uptake of 86Rb+. Decreasing availability of intracellular Na+ by blockade of Na+/K+/ 2Cl- symporters or Na+/H+ antiporters abolished the effects of both hormones on 86Rb+ uptake and enabled both GH and insulin to increase [Ca2+]i in GH-deprived adipocytes. The data suggest that hormonal stimulation of Na+/K+-ATPase activity interferes with activation of voltage-sensitive calcium channels by either membrane hyperpolarization or some unknown interaction between the sodium pump and calcium channels.     

Interleukin-2 induction of lymphokine-activated killer (LAK) activity in the peripheral blood and bone marrow of acute leukemia patients: II. Feasibility of LAK generation in children with active disease and in remission

Activation and expansion in culture with rIL-2 of peripheral blood (PB) and/or bone marrow (BM) specimens derived from children with ALL and ANLL, with active disease (AP) and in remission were studied (RP). Baseline NK cytolytic activity from AP was found to be depressed, whereas RP-derived cells had normal NK activity, as assayed against K562 targets. Culture in rIL-2 significantly enhanced the NK activity of both AP- and RP-derived cells and generated LAK activity, as assayed by 4-hour 51Cr release, against NK-resistant Raji cell line and against fresh, allogeneic, and autologous tumor cells. Lytic activity against fresh, cryopreserved leukemia blasts was of lower than that found against cell lines. In three patients higher lytic activity against autologous than against allogeneic blasts was demonstrated. Expansion in culture with rIL-2 varied from twofold to 120-fold. rIL-2 activation and expansion was better in RP than in AP. The predominant phenotype of activated cells, as determined by flow cytometry, was [mean % (SD)]: CD3- = 54 (12), CD8+ = 55 (17), and NKH1+ = 26 (7). The consistently high level of CD8+ cells was accompanied by very low levels of CD4+ cells: mean = 11% (14). Double-marker analysis showed mean of 33% (10) for CD3+/NKH1+ cells and mean = 32 (11) for CD8+/NKH1+ cells, implying that these populations were overlapping. Kinetics of expression of cell surface markers during 2 to 3 weeks in culture showed that CD8+ and NKH1+ enrichment occurred during the first week and lasted for up to 4 weeks, whereas CD4+ expression decreased after the second week. A significant decrease in the expression of IL-2 receptors (CD25) was observed from the second week of culture. This study shows the feasibility of in vitro generation of killer cells from PB and BM of pediatric leukemia patients.     

Refractoriness to growth hormone is associated with increased intracellular calcium in rat adipocytes.

In adipocytes that have been deprived of growth hormone (GH) for at least 3 hr, GH elicits a transient insulin-like response that is followed by a period of refractoriness to further insulin-like stimulation. Exposure of adipocytes to GH in the first hour of a 3-hr incubation prevents the appearance of insulin-like sensitivity. Intracellular Ca2+ concentration [( Ca2+]i) was measured in individual adipocytes that were loaded with fura-2 hexakis(acetoxymethyl) ester after preincubation in the presence (refractory) or absence (sensitive) of recombinant human GH at 100 ng/ml. Using a dual nitrogen laser imaging microscope with computer-assisted image processing to measure fluorescence changes, we observed that resting [Ca2+]i was 220 +/- 10 nM in refractory adipocytes and 110 +/- 6 nM in sensitive adipocytes (P less than 0.001). GH had no acute effect on [Ca2+]i in sensitive adipocytes but caused a sustained 3-fold increase in [Ca2+]i in refractory cells within 3 min (P less than 0.001). Insulin did not change [Ca2+]i in either sensitive or refractory adipocytes. In refractory cells treated with insulin and GH simultaneously, insulin completely blocked the rise in [Ca2+]i due to GH. Oxytocin elicited a prompt increase in [Ca2+]i followed by a quick return to resting levels in both sensitive and refractory cells. These findings indicate that basal [Ca2+]i is increased in refractory cells and that GH produces a sustained rise in [Ca2+]i only in refractory adipocytes. We suggest that the sustained increase in [Ca2+]i produced by GH in refractory cells prevents the expression of the insulin-like response.     

Activity of the purified mutagenesis proteins UmuC, UmuD'', and RecA in replicative bypass of an abasic DNA lesion by DNA polymerase III.

The introduction of a replication-inhibiting lesion into the DNA of Escherichia coli generates the induced, multigene SOS response. One component of the SOS response is a marked increase in mutation rate, dependent on RecA protein and the induced mutagenesis proteins UmuC and UmuD. A variety of previous indirect approaches have indicated that SOS mutagenesis results from replicative bypass of the DNA lesion by DNA polymerase III (pol III) holoenzyme in a reaction mediated by RecA, UmuC, and a processed form of UmuD termed UmuD'. To study the biochemistry of SOS mutagenesis, we have reconstituted replicative bypass with a defined in vitro system containing purified protein and a DNA substrate with a single abasic DNA lesion. The replicative bypass reaction requires pol III, UmuC, UmuD', and RecA. The nonprocessed UmuD protein does not replace UmuD' but inhibits the bypass activity of UmuD', perhaps by sequestering UmuD' in a heterodimer. Our experiments demonstrate directly that the UmuC-UmuD' complex and RecA act to rescue an otherwise stalled pol III holoenzyme at a replication-blocking DNA lesion.     

Pseudomonas aeruginosa serotype 0:9. New cause of whirlpool-associated dermatitis

In a five-day period, dermatitis developed in nearly one fourth of the guests staying at a large Georgia hotel. Dermatitis was associated with use of the hotel's whirlpool (p less than 0.001) and indoor swimming pool (p less than 0.001). Attack rates were highest among persons more frequently exposed to the whirlpool, in persons under 10 years of age, and during periods of heaviest bather load. Pseudomonas aeruginosa was isolated from skin lesions of 13 of 20 patients from whom culture specimens were taken. Ten isolates were serotype 0:9. The whirlpool's water grew P. aeruginosa serotype 0:9; however, the whirlpool's automatic chlorinator was functioning properly, the pH of the water was 7.2, and the free chlorine level was 0.6 mg/liter. This is the first report of a whirlpool-associated outbreak caused by P. aeruginosa serotype 0:9. Our findings suggest that this strain may not be readily sensitive to recommended chlorine concentrations.