Lymph node dendritic cells harbor inducible replication-competent HIV despite years of suppressive ART

Although gut and lymph node (LN) memory CD4 T cells represent major HIV and simian immunodeficiency virus (SIV) tissue reservoirs, the study of the role of dendritic cells (DCs) in HIV persistence has long been limited to the blood due to difficulties to access lymphoid tissue samples. In this study, we show that LN migratory and resident DC subpopulations harbor distinct phenotypic and transcriptomic profiles. Interestingly, both LN DC subpopulations contain HIV intact provirus and inducible replication-competent HIV despite the expression of the antiviral restriction factor SAMHD1. Notably, LN DC subpopulations isolated from HIV-infected individuals treated for up to 14 years are transcriptionally silent but harbor replication-competent virus that can be induced upon TLR7/8 stimulation. Taken together, these results uncover a potential important contribution of LN DCs to HIV infection in the presence of ART.

Progressive transformation of the HIV-1 reservoir cell profile over two decades of antiviral therapy

HIV-1 establishes a life-long reservoir of virally infected cells which cannot be eliminated by antiretroviral therapy (ART). Here, we demonstrate a markedly altered viral reservoir profile of long-term ART-treated individuals, characterized by large clones of intact proviruses preferentially integrated in heterochromatin locations, most prominently in centromeric satellite/micro-satellite DNA. Longitudinal evaluations suggested that this specific reservoir configuration results from selection processes that promote the persistence of intact proviruses in repressive chromatin positions, while proviruses in permissive chromosomal locations are more likely to be eliminated. A bias toward chromosomal integration sites in heterochromatin locations was also observed for intact proviruses in study participants who maintained viral control after discontinuation of antiretroviral therapy. Together, these results raise the possibility that antiviral selection mechanisms during long-term ART may induce an HIV-1 reservoir structure with features of deep latency and, possibly, more limited abilities to drive rebound viremia upon treatment interruptions.

A Possible Sterilizing Cure of HIV-1 Infection Without Stem Cell Transplantation

BACKGROUND

A sterilizing cure of HIV-1 infection has been reported in 2 persons living with HIV-1 who underwent allogeneic hematopoietic stem cell transplantations from donors who were homozygous for the CCR5Δ32 gene polymorphism. However, this has been considered elusive during natural infection.

OBJECTIVE

To evaluate persistent HIV-1 reservoir cells in an elite controller with undetectable HIV-1 viremia for more than 8 years in the absence of antiretroviral therapy.

DESIGN

Detailed investigation of virologic and immunologic characteristics.

SETTING

Tertiary care centers in Buenos Aires, Argentina, and Boston, Massachusetts.

PATIENT

A patient with HIV-1 infection and durable drug-free suppression of HIV-1 replication.

MEASUREMENTS

Analysis of genome-intact and replication-competent HIV-1 using near-full-length individual proviral sequencing and viral outgrowth assays, respectively; analysis of HIV-1 plasma RNA by ultrasensitive HIV-1 viral load testing.

RESULTS

No genome-intact HIV-1 proviruses were detected in analysis of a total of 1.188 billion peripheral blood mononuclear cells and 503 million mononuclear cells from placental tissues. Seven defective proviruses, some of them derived from clonally expanded cells, were detected. A viral outgrowth assay failed to retrieve replication-competent HIV-1 from 150 million resting CD4⁺ T cells. No HIV-1 RNA was detected in 4.5 mL of plasma.

LIMITATIONS

Absence of evidence for intact HIV-1 proviruses in large numbers of cells is not evidence of absence of intact HIV-1 proviruses. A sterilizing cure of HIV-1 can never be empirically proved.

CONCLUSION

Genome-intact and replication-competent HIV-1 were not detected in an elite controller despite analysis of massive numbers of cells from blood and tissues, suggesting that this patient may have naturally achieved a sterilizing cure of HIV-1 infection. These observations raise the possibility that a sterilizing cure may be an extremely rare but possible outcome of HIV-1 infection.

PRIMARY FUNDING SOURCE

National Institutes of Health and Bill & Melinda Gates Foundation.

Ferroportin 3 is a dual-targeted mitochondrial/chloroplast iron exporter necessary for iron homeostasis in Arabidopsis

Mitochondria and chloroplasts are organelles with high iron demand that are particularly susceptible to iron-induced oxidative stress. Despite the necessity of strict iron regulation in these organelles, much remains unknown about mitochondrial and chloroplast iron transport in plants. Here, we propose that Arabidopsis ferroportin 3 (FPN3) is an iron exporter that is dual-targeted to mitochondria and chloroplasts. FPN3 is expressed in shoots, regardless of iron conditions, but its transcripts accumulate under iron deficiency in roots. fpn3 mutants cannot grow as well as the wild type under iron-deficient conditions and their shoot iron levels are lower compared with the wild type. Analyses of iron homeostasis gene expression in fpn3 mutants and inductively coupled plasma mass spectrometry (ICP-MS) measurements show that iron levels in the mitochondria and chloroplasts are increased relative to the wild type, consistent with the proposed role of FPN3 as a mitochondrial/plastid iron exporter. In iron-deficient fpn3 mutants, abnormal mitochondrial ultrastructure was observed, whereas chloroplast ultrastructure was not affected, implying that FPN3 plays a critical role in the mitochondria. Overall, our study suggests that FPN3 is essential for optimal iron homeostasis.

PRC2-mediated H3K27me3 modulates shoot iron homeostasis in Arabidopsis thaliana

Plants use intricate mechanisms to adapt to changing iron conditions because iron is essential and also one of the most limiting nutrients for plant growth. Furthermore, iron is potentially toxic in excess and must be tightly regulated. Previously, we showed that chromatin remodeling via histone 3 lysine 27 trimethylation (H3K27me3) modulates the expression of FIT-dependent genes under iron deficiency in roots. This study builds on our previous findings, showing that H3K27me3 also modulates iron regulation in shoots. In the clf mutant, which lacks the predominant H3K27 tri-methyltransferase, we detected increased iron translocation to shoots under iron deficiency as compared to wild type. Transcriptomic analysis of shoots also revealed differential expression of genes consistent with higher iron levels in clf shoots than wild type shoots under iron-deficient conditions. In addition, we verify that YSL1 and IMA1, two genes involved in signaling iron status from shoots to roots, are direct targets of H3K27me3 and reveal iron-dependent deposition of H3K27me3 on these loci. This study contributes to a better understanding of the molecular mechanisms behind iron regulation in plants, as the effect of PRC2-mediated H3K27me3 on iron homeostasis genes expressed in the shoots has not been previously reported to our knowledge.

The Relationship of Participation in Sports and Physical Activity to Body Objectification, Instrumentality, and Locus of Control Among Young Women

The primary purposes of this study were to assess the possible relationship of sports participation during high school to body self-objectification, instrumentality and locus of control, and to explore the possibility that different sports might be differentially related to psychological variables according to the perceived stereotypical masculinity or femininity of the sport. Two studies were reported herein. In the first, using 195 male and female students, we examined perceptions of sports according to emphasis on physical appearance and perceived masculinity/femininity. These findings were used in Study 2, which included 437 college women, to describe sports participation along dimensions of both extent of participation and the nature of the sports in which the individual participated. Extent of participation in physical fitness activity was also assessed. Participation in sports and/or physical activity was associated with higher scores on the body shame subscale of McKinley and Hyde's (1996) Objectified Body Consciousness Scale, which indicates greater internalization of cultural standards of female beauty. Body shame was also related to participation in more “feminine” sports (those focusing more on female appearance). Physical activity was also consistently related to both instrumentality and locus of control. Further research is needed to understand the relationship of sports and physical exercise activities to body self-objectification and other indicators of psychological functioning among women.

Postprocedural hypotension after carotid artery stent placement: predictors and short- and long-term clinical outcomes

PURPOSE

To describe the predictors of persistent hypotension after carotid artery stent (CAS) placement and define the clinical outcome of patients with this hemodynamic disturbance.

MATERIALS AND METHODS

One hundred forty CAS procedures were performed in 133 consecutive patients. Post-CAS hypotension-defined as a greater than 40 mm Hg decrease in arterial pressure without evidence of hypovolemia, with a systolic pressure lower than 90 mm Hg at the end of CAS and lasting at least 1 hour-was observed in 25 patients (group 1); 108 patients did not have hypotension (group 2).

RESULTS

Post-CAS hypotension developed in 33.9% of cases after balloon-expandable stent placement versus in 13.6% of cases after self-expanding stent placement (P =.04). In-hospital minor ipsilateral strokes occurred in 16% of cases in group 1 versus in 3% of cases in group 2 (P =.03). There was one (0.9%) major stroke (transient) and three (2.6%) transient ischemic attacks, all of which occurred in group 2 (not significant vs group 1 for both conditions). At 10 months +/- 4 (SD) of follow-up, there was greater total mortality in group 1 than in group 2 (20% vs 4%, P =.02), whereas neurologic events did not differ significantly between the groups.

CONCLUSION

Hypotension due to carotid sinus stimulation is frequent after CAS with balloon-expandable stents. This phenomenon correlates with increased in-hospital complications and long-term risk of death.

The geography of fundholding in southwest England: implications for the evolution of primary care groups

Using postcode-ED linkage to calculate patient-weighted deprivation indices for 330 general practices in southwest England, this study examines whether the populations served by fundholding and non-fundholding practices varied with respect to socio-economic status. Little evidence is found of systematic socio-economic bias in the uptake of fundholding. However, a distinct spatial pattern to the distribution of fundholding is revealed in this article, urban practices having adopted the scheme more readily than their rural and mixed rural/urban counterparts. As practice-level fundholding is replaced by commissioning at the locality level, such geographical variation is likely to be expressed in the way in which primary care groups evolve.

Injury to a patent left internal thoracic artery graft at coronary reoperation

BACKGROUND

The purpose of this study was to determine the prevalence, outcome, and operative strategies for patients having injury to a patent left internal thoracic artery (LITA) graft to the left anterior descending coronary artery (LAD) at coronary reoperation.

METHODS

Of 655 patients with a patent LITA graft to the LAD undergoing coronary reoperation from 1986 to 1997, 35 (5.3%) sustained intraoperative injury to the LITA graft.

RESULTS

Strategies to restore flow to the LAD included new saphenous vein graft to the LAD in 15 patients, saphenous vein graft to the LITA stump in 7, saphenous vein graft to the LAD and repair of the LITA graft in 6, and other strategies in 7. All or part of the LITA graft to the LAD was salvaged in 20 patients (57%). Fourteen patients (40%) sustained perioperative myocardial infarction, and 3 patients died (8.6%). The 3 patients who died all had stenosis or thrombosis of the graft to the LAD documented at autopsy.

CONCLUSIONS

We conclude that (1) the prevalence of injury to a patent LITA graft is 5.3%; (2) a variety of techniques can be used to restore blood flow to the LAD; and (3) ineffective revascularization of the LAD in this situation is associated with operative mortality. At primary coronary artery bypass grafting, the LITA pedicle should be positioned in the left chest away from the posterior sternal table; this strategy may minimize the risk of LITA graft injury at coronary reoperation.

Comparison of two progestogens during out-of-season breeding in a commercial ewe flock

A comparison was made of the relative effectiveness of subcutaneous ear implants containing 2 mg Norgestomet or vaginal pessaries containing 60 mg medroxyprogesterone acetate (MAP) to induce estrus and conception in dry anestrous ewes. Groups of ewes were treated with one of the two progestogens for 14 d, and 500 IU pregnant mare serum gonadotropin (PMSG) was administered intramuscularly at the time of progestogen withdrawal. No significant differences in estrus induction, pregnancy rate or number of lambs born per ewe lambing were observed. Ewes treated with Norgestomet had 96% estrus, 60% pregnancy rate and 1.4 lambs per ewe lambing. Comparably, ewes treated with MAP had 94% estrus, 65% pregnancy rate and 1.7 lambs per ewe lambing. Norgestomet implants compared favorably with MAP pessaries for estrus induction and breeding of commercial, dry anestrous ewes.

Ideological goals of different health insurance plans

Questionnaires sent to and interviews with managerial personnel in two types of health insurance organizations revealed substantial differences in their goals. Top policy makers, executive managers, and lower level management personnel (in all 165 people from four entities) were questioned. Although differences occurred among the various administrative levels, the commercial companies were more strongly oriented toward profit and growth and the prepaid group practice plans more strongly oriented toward service and community relations. These findings were confirmed by a study of the public statements of these organizations. The findings would seem to have relevance to the use of insurance companies by the government in implementation of any national health insurance program.

Quality of medical care: a factor analysis approach using medical records

A relatively inexpensive, reliable, and unobtrusive method is described for measuring the content of medical care. Factor analysis of the content of the records of more than 11,000 physician-patient encounters from six different health insurance plans extracted four main factors or dimensions that together explained 42 percent of the variance in record content. Appropriate names for these dimensions appear to be: "prevention," "rationality," "verification," and "continuity." The method is tested by scoring the six insurance plans on the four factors.