Nitrite from inflammatory cells—A cancer risk factor in ulcerative colitis?

Elevated levels of luminal nitrite and a lowered luminal pH were found in 77 percent of patients with acute ulcerative colitis. No luminal nitrite was found in healthy control subjects. Nitrites are a secretory product of activated macrophages and neutrophils of the lamina propria, whereas the lowered luminal pH is due to diminished bicarbonate formation by impaired colonocytes. A hypothesis is put forward that nitrites, lowered pH, and bacterial amines are conducive to formation of carcinogenic n-nitroso compounds, which reflect a cancer risk in patients with ulcerative colitis dependent on the type and extent of inflammatory cell activation as well as metabolic impairment of colonic epithelial cells.     

Acetylcholinesterase in the human erythron. II. Biochemical assay

Acetylcholinesterase (AChE) is an integral erythrocyte membrane protein. A role for the enzyme in the developing human erythron is being explored. Assays of AchE by the standard Ellman technique overestimate the amount of enzyme by failing to account for the contribution of hemoglobin to the optical density of the reaction mixture. Furthermore, reliance on substrate selection alone for specificity is unsatisfactory. Incorporation of inhibitors of "true" AchE and of pseudocholinesterase confer greater ability to distinguish one enzyme from the other. In our experience, the inhibitor constant (Kl) for edrophonium, which is highly specific for AChE, is approximately 5 x 10(-5) M against adult human erythrocytes that contain significantly more total cholinesterase activity than do erythrocytes from umbilical cord blood. This consists of both "true" and "pseudo" enzyme, the former predominating and accounting for 0.75-1.65 (mean 1.02, median 0.87) femtomoles of substrate hydrolysed per min per cell in adult blood, with values of 0.15-1.04 (mean 0.71, median 0.73) obtained on cord blood. Moreover, the enzyme activity in neonatal erythrocytes has a rather different inhibitor profile from that of adult cells. AChE was also demonstrated in fresh (ALL) and cultured (K562 and HL60) human leukemic cells, as well as in primitive granulocyte-macrophage and erythroid cells cloned from normal human bone marrow. In the erythroid colonies the enzyme activity was 0-3.76 (mean 1.20, median 0.76) femtomoles per min per cell, apparently the first successful measurement of AChE in such cells.     

An adenoviral vector deleted for all viral coding sequences results in enhanced safety and extended expression of a leptin transgene

Adenoviral (Ad)-mediated in vivo gene transfer and expression are limited in part by cellular immune responses to viral-encoded proteins and/or transgene immunogenicity. In an attempt to diminish the former responses, we have previously developed and described helper-dependent (HD) Ad vectors in which the viral protein coding sequences are completely eliminated. These HD vectors have up to 37 kb insert capacity, are easily propagated in a Cre recombinase-based system, and can be produced to high concentration and purity (>99.9% helper-free vector). In this study, we compared safety and efficacy of leptin gene delivery mediated by an HD vector (HD-leptin) and a first-generation E1-deleted Ad vector (Ad-leptin) in normal lean and ob/ob (leptin-deficient) mice. In contrast to evidence of liver toxicity, inflammation, and cellular infiltration observed with Ad-leptin delivery in mice, HD-leptin delivery was associated with a significant improvement in associated safety/toxicity and resulted in efficient gene delivery, prolonged elevation of serum leptin levels, and associated weight loss. The greater safety, efficient gene delivery, and increased insert capacity of HD vectors are significant improvements over current Ad vectors and represent favorable features especially for clinical gene therapy applications.     

Psychosocial Functioning and Depressive Symptoms Among HIV-Positive Persons Receiving Care and Treatment in Kenya,Namibia, and Tanzania

In sub-Saharan Africa, the prevalence of depressive symptoms among people living with HIV (PLHIV) is considerably greater than that among members of the general population. It is particularly important to treat depressive symptoms among PLHIV because they have been associated with poorer HIV care-related outcomes. This study describes overall psychosocial functioning and factors associated with depressive symptoms among PLHIV attending HIV care and treatment clinics in Kenya, Namibia, and Tanzania. Eighteen HIV care and treatment clinics (six per country) enrolled approximately 200 HIV-positive patients (for a total of 3,538 participants) and collected data on patients’ physical and mental well-being, medical/health status, and psychosocial functioning. Although the majority of participants did not report clinically significant depressive symptoms (72 %), 28 % reported mild to severe depressive symptoms, with 12 % reporting severe depressive symptoms. Regression models indicated that greater levels of depressive symptoms were associated with: (1) being female, (2) younger age, (3) not being completely adherent to HIV medications, (4) likely dependence on alcohol, (5) disclosure to three or more people (versus one person), (6) experiences of recent violence, (7) less social support, and (8) poorer physical functioning. Participants from Kenya and Namibia reported greater depressive symptoms than those from Tanzania. Approximately 28 % of PLHIV reported clinically significant depressive symptoms. The scale-up of care and treatment services in sub-Saharan Africa provides an opportunity to address psychosocial and mental health needs for PLHIV as part of comprehensive care.     

Adoption,Reach, Implementation,and Maintenance of a Behavioral and Mental Health Assessment in Primary Care

PURPOSE

Guidelines recommend screening patients for unhealthy behaviors and mental health concerns. Health risk assessments can systematically identify patient needs and trigger care. This study seeks to evaluate whether primary care practices can routinely implement such assessments into routine care.

METHODS

As part of a cluster-randomized pragmatic trial, 9 diverse primary care practices implemented My Own Health Report (MOHR)—an electronic or paper-based health behavior and mental health assessment and feedback system paired with counseling and goal setting. We observed how practices integrated MOHR into their workflows, what additional practice staff time it required, and what percentage of patients completed a MOHR assessment (Reach).

RESULTS

Most practices approached (60%) agreed to adopt MOHR. How they implemented MOHR depended on practice resources, informatics capacity, and patient characteristics. Three practices mailed patients invitations to complete MOHR on the Web, 1 called patients and completed MOHR over the telephone, 1 had patients complete MOHR on paper in the office, and 4 had staff help patients complete MOHR on the Web in the office. Overall, 3,591 patients were approached and 1,782 completed MOHR (Reach = 49.6%). Reach varied by implementation strategy with higher reach when MOHR was completed by staff than by patients (71.2% vs 30.2%, P <.001). No practices were able to sustain the complete MOHR assessment without adaptations after study completion. Fielding MOHR increased staff and clinician time an average of 28 minutes per visit.

CONCLUSIONS

Primary care practices can implement health behavior and mental health assessments, but counseling patients effectively requires effort. Practices will need more support to implement and sustain assessments.     

Myeloid cell microsomal prostaglandin E synthase-1 fosters atherogenesis in mice

Microsomal prostaglandin E synthase-1 (mPGES-1) in myeloid and vascular cells differentially regulates the response to vascular injury, reflecting distinct effects of mPGES-1–derived PGE₂ in these cell types on discrete cellular components of the vasculature. The cell selective roles of mPGES-1 in atherogenesis are unknown. Mice lacking mPGES-1 conditionally in myeloid cells (Mac-mPGES-1-KOs), vascular smooth muscle cells (VSMC-mPGES-1-KOs), or endothelial cells (EC-mPGES-1-KOs) were crossed into hyperlipidemic low-density lipoprotein receptor-deficient animals. En face aortic lesion analysis revealed markedly reduced atherogenesis in Mac-mPGES-1-KOs, which was concomitant with a reduction in oxidative stress, reflective of reduced macrophage infiltration, less lesional expression of inducible nitric oxide synthase (iNOS), and lower aortic expression of NADPH oxidases and proinflammatory cytokines. Reduced oxidative stress was reflected systemically by a decline in urinary 8,12-iso-iPF_2α-VI. In contrast to exaggeration of the response to vascular injury, deletion of mPGES-1 in VSMCs, ECs, or both had no detectable phenotypic impact on atherogenesis. Macrophage foam cell formation and cholesterol efflux, together with plasma cholesterol and triglycerides, were unchanged as a function of genotype. In conclusion, myeloid cell mPGES-1 promotes atherogenesis in hyperlipidemic mice, coincident with iNOS-mediated oxidative stress. By contrast, mPGES-1 in vascular cells does not detectably influence atherogenesis in mice. This strengthens the therapeutic rationale for targeting macrophage mPGES-1 in inflammatory cardiovascular diseases.Nonsteroidal anti-inflammatory drugs (NSAIDs) reduce pain and inflammation by suppressing the formation of proinflammatory prostaglandins (PGs), particularly prostaglandin E₂ (PGE₂) formed by cyclooxygenase-2 (COX-2) (1). However, the development of NSAIDs specific for inhibition of COX-2 revealed a cardiovascular hazard attributable to suppression of cardioprotective PGs, especially prostacyclin (PGI₂) (2). This risk appears to extend to some of the older NSAIDs, like diclofenac, that also inhibit specifically COX-2 (3, 4). These developments prompted interest in microsomal PGE synthase (mPGES)-1 as a downstream alternative drug target to COX-2 (5): it is the dominant source among PGES enzymes in the biosynthesis of PGE₂ (6). Unlike NSAIDs, inhibitors of mPGES-1 would spare PGI₂ from suppression. Indeed, blockade or deletion of mPGES-1 results in accumulation of its PGH₂ substrate, rendering it available for metabolism by other PG synthases, including PGI₂ synthase (PGIS) (7).Consistent with these observations, we have found that whereas deletion of COX-2 in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) renders mice susceptible to thrombosis and hypertension (2), deletion of mPGES-1 in vascular cells has no such effect (8). Indeed, global deficiency of mPGES-1 restrains atherogenesis (9), the proliferative response to vascular injury (10) and angiotensin-induced aortic aneurysm formation (11) in mice.Despite this attractive cardiovascular profile, mPGES-1 is a complex drug target. The dominant prostanoid products of substrate rediversion differ among cell types. For example, whereas PGI₂ might be augmented in vascular cells, the consequence of mPGES-1 blockade in other cells might be an increase in thromboxane (Tx)A₂, a PG that promotes platelet activation, vasoconstriction, and atherogenesis (9). Even if an increase in PGI₂ afforded a desirable cardiovascular profile, it might undermine the analgesic efficacy of mPGES-1 inhibitors. Although the impacts of global deletion of mPGES-1 and COX-2 in many mouse models of analgesia are indistinguishable (12, 13), in some, PGI₂ rather than PGE₂ predominates (14) and thus may be the dominant mediator in certain subtypes of human pain. Finally, the consequences of PGE₂ suppression might differ between cell types. PGE₂ activates four E prostanoid (EP) receptors with contrasting intracellular signaling and consequent biology (15, 16). Indeed, the contrasting effect of mPGES-1 deletion in myeloid vs. vascular cells on the proliferative response to vascular injury reflects the differential consequences of EP activation rather than substrate rediversion (8).A potentially discriminating feature among inhibitors of COX-2 and mPGES-1 is their effect on atherosclerosis. Global postnatal deletion of COX-2 accelerates atherogenesis in hyperlipidemic mice (17), an observation that accords with a similar effect of deleting the PGI₂ receptor (the IP) (18, 19) and with the delayed detection of a cardiovascular hazard in randomized trials of COX-2 inhibitors in patients initially selected for being at low cardiovascular risk (20). By contrast, global deletion of mPGES-1 restrains atherogenesis in mice; in this case suppression of PGE₂ coincides with an increase in biosynthesis of PGI₂ (9). Here, we wished to segregate the effects on atherosclerosis of mPGES-1 depletion in myeloid from vascular cells. Our results strengthen the rationale for targeting macrophage mPGES-1 in the treatment of inflammatory cardiovascular disease.     

Levels of satisfaction with rheumatoid arthritis treatment and associated alignment between physicians and patients across Latin America

Clinical Rheumatology - Discordance (misalignment) regarding treatment satisfaction may exist in real-life clinical practice between patients and their physicians. We aimed to assess physician and...