Morphine for the treatment of pain in sickle cell disease.

Pain is a hallmark of sickle cell disease (SCD) and its treatment remains challenging. Opioids are the major family of analgesics that are commonly used for treating severe pain. However, these are not always effective and are associated with the liabilities of their own. The pharmacology and multiorgan side effects of opioids are rapidly emerging areas of investigation, but there remains a scarcity of clinical studies. Due to opioid-induced endothelial-, mast cell-, renal mesangial-, and epithelial-cell-specific effects and proinflammatory as well as growth influencing signaling, it is likely that when used for analgesia, opioids may have organ specific pathological effects. Experimental and clinical studies, even though extremely few, suggest that opioids may exacerbate existent organ damage and also stimulate pathologies of their own. Because of the recurrent and/or chronic use of large doses of opioids in SCD, it is critical to evaluate the role and contribution of opioids in many complications of SCD. The aim of this review is to initiate inquiry to develop strategies that may prevent the inadvertent effect of opioids on organ function in SCD, should it occur, without compromising analgesia

Sickle cell pain: a critical reappraisal.

Sickle cell pain includes 3 types: acute recurrent painful crises, chronic pain syndromes, and neuropathic pain. The acute painful crisis is the hallmark of the disease and the most common cause of hospitalization and treatment in the emergency department. It evolves through 4 phases: prodromal, initial, established, and resolving. Each acute painful episode is associated with inflammation that worsens with recurrent episodes, often culminating in serious complications and organ damage, such as acute chest syndrome, multiorgan failure, and sudden death. Three pathophysiologic events operate in unison during the prodromal phase of the crisis: vaso-occlusion, inflammation, and nociception. Aborting the acute painful episode at the prodromal phase could potentially prevent or minimize tissue damage. Our hypothesis is that managing these events with hydration, anti-inflammatory drugs, aggressive analgesia, and possibly vasodilators could abort the crisis and prevent or minimize further damage. Chronic pain syndromes are associated with or accompany avascular necrosis and leg ulcers. Neuropathic pain is not well studied in patients with sickle cell disease but has been modeled in the transgenic sickle mouse. Management of sickle cell pain should be based on its own pathophysiologic mechanisms rather than borrowing guidelines from other nonsickle pain syndromes

Reduced renal function is associated with progression to AIDS but not with overall mortality in HIV-infected kenyan adults not initially requiring combination antiretroviral therapy

<p>Abstract</p> <p>Background</p> <p>The World Health Organization (WHO) has recently recommended that antiretrovirals be initiated in all individuals with CD4 counts of less than 350 cells/mm³. For countries with resources too limited to expand care to all such patients, it would be of value to able to identify and target populations at highest risk of HIV progression. Renal disease has been identified as a risk factor for disease progression or death in some populations.</p> <p>Methods</p> <p>Times to meeting combination antiretroviral therapy (cART) initiation criteria (developing either a CD4 count < 200 cells/mm³or WHO stage 3 or 4 disease) and overall mortality were evaluated in cART-naïve, HIV-infected Kenyan adults with CD4 cell counts ≥200/mm³and with WHO stage 1 or 2 disease. Cox proportional hazard regression models were used to evaluate the associations between renal function and these endpoints.</p> <p>Results</p> <p>We analyzed data of 7383 subjects with a median follow-up time of 59 (interquartile range, 27-97) weeks. In Cox regression analyses adjusted for age, sex, WHO disease stage, CD4 cell count and haemoglobin, estimated creatinine clearance (CrCl) < 60 mL/min was significantly associated with shorter times to meeting cART initiation criteria (HR 1.34; 95% CI, 1.23-1.52) and overall mortality (HR 1.73; 95% CI, 1.19-2.51) compared with CrCl ≥60 mL/min. Estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m²was associated with shorter times to meeting cART initiation criteria (HR 1.39; 95% CI, 1.22-1.58), but not with overall mortality. CrCl and eGFR remained associated with shorter times to cART initiation criteria, but neither was associated with mortality, in weight-adjusted analyses.</p> <p>Conclusions</p> <p>In this large natural history study, reduced renal function was strongly associated with faster HIV disease progression in adult Kenyans not initially meeting cART initiation criteria. As such, renal function measurement in resource-limited settings may be an inexpensive method to identify those most in need of cART to prevent progression to AIDS. The initial association between reduced CrCl, but not reduced eGFR, and greater mortality was explained by the low weights in this population.</p

MMPs/TIMPs imbalances in the peripheral blood and cerebrospinal fluid are associated with the pathogenesis of HIV-1-associated neurocognitive disorders: A pilot study

HIV-1-associated neurocognitive disorders (HAND) continue to be a major concern in the infected population, despite the widespread use of combined antiretroviral therapy (cART). Growing evidence suggests that an imbalance between matrix metalloproteinases (MMPs) and endogenous tissue inhibitors of MMPs (TIMPs) contributes to the pathogenesis of HAND. In our present study, we examined protein levels and enzymatic activities of MMPs and TIMPs in both plasma and cerebrospinal fluid (CSF) samples from HIV-1 patients with or without HAND and HIV-1-negative controls. Imbalances between MMPs and TIMPs with distinct patterns were revealed in both the peripheral blood and CSF of HIV-1 patients, especially those with HAND. In the peripheral blood, the protein levels of MMP-2, MMP-9, TIMP-1, TIMP-2, and the enzymatic activities of MMP-2 and MMP-9 were increased in HIV-1 patients with or without HAND when compared with HIV-1-negative controls. The enzymatic activity of MMP-2, but not MMP-9, was further increased in plasma samples of HAND patients than that of HIV-1 patients without HAND. Notably, the ratio of MMP-2/TIMP-2 in plasma was significantly increased in HAND patients, not in patients without HAND. In the CSF, MMP-2 activity was increased, but the ratio of MMP-2/TIMP-2 was not altered. De novo induction and activation of MMP-9 in the CSF of HAND patients was particularly prominent. The imbalances between MMPs and TIMPs in the blood and CSF were related to the altered profiles of inflammatory cytokines/chemokines and monocyte activation in these individuals. In addition, plasma from HIV-1 patients directly induced integrity disruption of an in vitro blood-brain barrier (BBB) model, leading to increased BBB permeability and robust transmigration of monocytes/macrophages. These results indicate that imbalances between MMPs and TIMPs are involved in BBB disruption and are implicated in the pathogenesis of neurological disorders such as HAND in HIV-1 patients

Excitation of whispering gallery modes with a "point-and-play", fiber-based, optical nano-antenna

We demonstrate the excitation and detection of whispering gallery modes in optical microresonators using a "point-and-play", fiber-based, optical nano-antenna. The coupling mechanism is based on cavity-enhanced Rayleigh scattering. Collected spectra exhibit Lorentzian dips, Fano shapes, or Lorentzian peaks, with a coupling efficiency around 13\%. The spectra are characterized by the coupling gap, polarization, and fiber tip position. The coupling method is simple, low-cost and, most importantly, the \textit{Q}-factor can be maintained at $10^8$ over a wide coupling range, thereby making it suitable for metrology, sensing, or cavity quantum electrodynamics (cQED) experiments

GCH1 haplotypes and cardiovascular risk in HIV

Heightened systemic inflammation contributes to cardiovascular (CVD) events in people living with HIV (PLWH), though not all PLWH develop CVD, thus suggesting a genetic modifying role. We examined GCH1 polymorphisms, which have been associated with reduced endothelial function in European populations with CVD and increased inflammation, in a racially diverse cohort of U.S. PLWH initiating antiretroviral therapy (ART). GCH1 polymorphisms differed by race and were not associated flow-mediated dilation or carotid intima media thickness before or after 48 weeks of ART

A two week regimen of high dose integrase inhibitors does not cause nephrotoxicity in mice

Background The integrase inhibitors, raltegravir and dolutegravir, are nucleoside reverse transcriptase inhibitor-sparing agents which may be used as part of first-line antiretroviral therapy for HIV. These drugs inhibit creatinine secretion through organic cation transporters, thus elevating serum creatinine without affecting glomerular filtration. We sought to determine whether subtle signs of nephrotoxicity could be observed in mice administered a two-week regimen of high-dose integrase inhibitors. Methods C57BL/6 mice were fed standard water (CTRL, n = 6), raltegravir-containing water (40 mg/kg/day, n = 6), or dolutegravir-containing water (2.7 mg/kg/day, n = 6) for two weeks and sacrificed. Endpoints were assessed including urine microalbumin, kidney injury molecule-1 renal tissue gene expression, renal histopathology, serum creatinine, and blood urea nitrogen. Results The results are NOT consistent with a direct nephrotoxic effect of the integrase inhibitors in mice. Serum creatinine was significantly elevated in raltegravir and dolutegravir mice (p < 0.05) compared to control (raltegravir = 0.25 mg/dl, dolutegravir = 0.30 mg/dl versus CTRL = 0.17 mg/dl). Blood urea nitrogen, cystatin C, and urine microalbumin were unchanged. Kidney injury molecule-1 tissue expression in raltegravir and dolutegravir groups was nonsignificantly elevated compared to control (1.2-fold compared to control). Renal histopathology by periodic acid–Schiff staining failed to reveal glomerular or tubular renal injury in any group. Conclusion These studies are consistent with integrase inhibitors competitively inhibiting creatinine secretion. While no evidence of direct nephrotoxicity was observed after two weeks of high-dose drug administration, additional studies may be performed to understand whether these drugs lead to chronic nephropathy

HIV envelope protein gp120-induced apoptosis in lung microvascular endothelial cells by concerted upregulation of EMAP II and its receptor, CXCR3

Chronic lung diseases, such as pulmonary emphysema, are increasingly recognized complications of infection with the human immunodeficiency virus (HIV). Emphysema in HIV may occur independent of cigarette smoking, via mechanisms that are poorly understood but may involve lung endothelial cell apoptosis induced by the HIV envelope protein gp120. Recently, we have demonstrated that lung endothelial apoptosis is an important contributor to the development of experimental emphysema, via upregulation of the proinflammatory cytokine endothelial monocyte-activating polypeptide II (EMAP II) in the lung. Here we investigated the role of EMAP II and its receptor, CXCR3, in gp120-induced lung endothelial cell apoptosis. We could demonstrate that gp120 induces a rapid and robust increase in cell surface expression of EMAP II and its receptor CXCR3. This surface expression occurred via a mechanism involving gp120 signaling through its CXCR4 receptor and p38 MAPK activation. Both EMAP II and CXCR3 were essentially required for gp120-induced apoptosis and exposures to low gp120 concentrations enhanced the susceptibility of endothelial cells to undergo apoptosis when exposed to soluble cigarette smoke extract. These data indicate a novel mechanism by which HIV infection causes endothelial cell loss involved in lung emphysema formation, independent but potentially synergistic with smoking, and suggest therapeutic targets for emphysema prevention and/or treatment