Evidence for anti-VEGF treatment of diabetic macular edema.

Diabetic macular edema (DME) is the most important cause of vision loss in patients with diabetes mellitus. Diabetic retinopathy has a remarkable impact on public health and on the quality of life of diabetic patients and thus requires special consideration. The first line of treatment remains the management of systemic risk factors but is often insufficient in controlling DME and currently, laser retinal photocoagulation is considered the standard of care. However, laser treatment reduces the risk of moderate visual loss by approximately 50% without guaranteeing remarkable effects on visual improvement. For these reasons, new strategies in the treatment of DME have been studied, in particular the use of anti-vascular endothelial growth factor (anti-VEGF) drugs. VEGF is a pluripotent growth factor that acts as a vasopermeability factor and an endothelial cell mitogen. For this reason, it represents an interesting candidate as a therapeutic target for the treatment of DME. The aim of this article is to review the evidence behind the use of anti-VEGF drugs in the treatment of DME.

The importance of nef in the induction of human immunodeficiency virus type 1 replication from primary quiescent CD4 lymphocytes.

The viral regulatory gene, nef, is unique to the human immunodeficiency viruses (HIV) and their related primate lentiviruses. Expression of the nef gene has been shown to be essential to the maintenance of high levels of virus replication and the development of pathogenesis in the animal model of simian immunodeficiency virus (SIV) infection. In contrast to this in vivo model, the use of standard T cell culture systems to study nef function in vitro has produced a spectrum of contradictory results, and has failed to demonstrate a significant positive influence of nef on viral life cycle. We have developed a cell model to study regulation of HIV-1 replication that we believe reflects more accurately virus-cell interactions as they occur in vivo. Our experimental system used acute virus infection of purified, quiescent CD4 lymphocytes and subsequent induction of viral replication through T cell activation. With this cell model, NL4-3 virus clones with open and mutated nef reading frames were compared for replication competence. The clones with nef mutations showed reproducible and significant reductions in both rates of growth and maximal titers achieved. The degree of reduced replication was dependent on initial virus inoculum and the timing of T cell activation. The influence of nef was highly significant for induction of virus replication from a latent state within resting CD4 cells. Its effect was less apparent for virus infection of fully proliferating CD4 cells. This study demonstrates that nef confers a positive growth advantage to HIV-1 that becomes readily discernable in the primary cell setting of virus induction through T cell activation. The experimental cell model, which we describe here, provides not only a means to study nef function in vitro, but also provides important clues to the function of nef in HIV infection in vivo.

Viral dynamics of acute HIV-1 infection.

Viral dynamics were intensively investigated in eight patients with acute HIV infection to define the earliest rates of change in plasma HIV RNA before and after the start of antiretroviral therapy. We report the first estimates of the basic reproductive number (R(0)), the number of cells infected by the progeny of an infected cell during its lifetime when target cells are not depleted. The mean initial viral doubling time was 10 h, and the peak of viremia occurred 21 d after reported HIV exposure. The spontaneous rate of decline (alpha) was highly variable among individuals. The phase 1 viral decay rate (delta(I) = 0.3/day) in subjects initiating potent antiretroviral therapy during acute HIV infection was similar to estimates from treated subjects with chronic HIV infection. The doubling time in two subjects who discontinued antiretroviral therapy was almost five times slower than during acute infection. The mean basic reproductive number (R(0)) of 19.3 during the logarithmic growth phase of primary HIV infection suggested that a vaccine or postexposure prophylaxis of at least 95% efficacy would be needed to extinguish productive viral infection in the absence of drug resistance or viral latency. These measurements provide a basis for comparison of vaccine and other strategies and support the validity of the simian immunodeficiency virus macaque model of acute HIV infection.

HIV-specific CD8(+) T cells produce antiviral cytokines but are impaired in cytolytic function.

The use of peptide-human histocompatibility leukocyte antigen (HLA) class I tetrameric complexes to identify antigen-specific CD8(+) T cells has provided a major development in our understanding of their role in controlling viral infections. However, questions remain about the exact function of these cells, particularly in HIV infection. Virus-specific cytotoxic T lymphocytes exert much of their activity by secreting soluble factors such as cytokines and chemokines. We describe here a method that combines the use of tetramers and intracellular staining to examine the functional heterogeneity of antigen-specific CD8(+) T cells ex vivo. After stimulation by specific peptide antigen, secretion of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1beta, and perforin is analyzed by FACS((R)) within the tetramer-positive population in peripheral blood. Using this method, we have assessed the functional phenotype of HIV-specific CD8(+) T cells compared with cytomegalovirus (CMV)-specific CD8(+) T cells in HIV chronic infection. We show that the majority of circulating CD8(+) T cells specific for CMV and HIV antigens are functionally active with regards to the secretion of antiviral cytokines in response to antigen, although a subset of tetramer-staining cells was identified that secretes IFN-gamma and MIP-1beta but not TNF-alpha. However, a striking finding is that HIV-specific CD8(+) T cells express significantly lower levels of perforin than CMV-specific CD8(+) T cells. This lack of perforin is linked with persistent CD27 expression on HIV-specific cells, suggesting impaired maturation, and specific lysis ex vivo is lower for HIV-specific compared with CMV-specific cells from the same donor. Thus, HIV-specific CD8(+) T cells are impaired in cytolytic activity.

A study of three polymorphic sites of ADA gene in colon cancer.

Adenosine inhibits the immune response in tumors. Adenosine deaminase (ADA) controls adenosine level and as ecto-enzyme acts as costimulatory molecule of adenosine receptors and/or CD26. We examined ADA1, ADA2, ADA6 polymorphic sites of ADA gene in 109 subjects with colon cancer from Rome's population and in 246 blood donors as controls from the same population. In colon cancer ADA1*2/ADA2*1 haplotype is more represented, while ADA1*2/ADA2*2 is less represented than in controls. ADA2*2/ADA6*2 is less represented in patients than in controls. Polymorphic sites of ADA might influence cell-mediated anti-tumor immune responses controlling adenosine level and extraenzymatic protein functions.

Impact of multivessel coronary disease on long-term outcome after percutaneous recanalization of coronary chronic total occlusions.

AIM: Percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) is common even with concomitant multivessel disease. We aimed to investigate the impact of multivessel disease on long-term outcome after PCI for CTO. METHODS: We collected baseline, procedural and follow-up data on patients undergoing successful PCI with stenting for CTO. We divided our population into three groups: patients with 1 vessel disease (1VD), those with 2-vessel disease (2VD) and subjects with 3-vessel disease (3VD). The primary end-point was the occurrence of major adverse cardiac events (MACE), i.e. death, myocardial infarction or target vessel revascularization. RESULTS: A total of 111 patients were included: 24 (21%) in group 1VD, 28 (25%) in group 2VD, and 59 (53%) in group 3VD. Clinical follow-up was available in 109 (98%) of them after a median of 27 months (range 6-68), yielding MACE rates of 1 (4%) in group 1VD, 5 (18%) in group 2VD, and 17 (29%) in group 3VD, respectively (P=0.03). No statistically significant difference was found comparing the 3 groups for the individual rates of death, myocardial infarction or target vessel revascularization (all P>0.05). No case of definite or probable stent thrombosis was adjudicated, despite use of DES in 99 (89%) patients. CONCLUSION: Patients with diffuse coronary disease undergoing PCI for a CTO fare a significantly worse prognosis. Nonetheless, despite liberal use of DES, stent thrombosis is rare in this setting, without differences according to the initial severity of disease, thus supporting the long-term safety of DES, even if used in this "off-label" context.

Recovery of replication-competent HIV despite prolonged suppression of plasma viremia.

In evaluating current combination drug regimens for treatment of human immunodeficiency virus (HIV) disease, it is important to determine the existence of viral reservoirs. After depletion of CD8 cells from the peripheral blood mononuclear cells (PBMCs) of both patients and normal donors, activation of patient CD4 lymphocytes with immobilized antibodies to CD3 and CD28 enabled the isolation of virus from PBMCs of six patients despite the suppression of their plasma HIV RNA to fewer than 50 copies per milliliter for up to 2 years. Partial sequencing of HIV pol revealed no new drug resistance mutations or discernible evolution, providing evidence for viral latency rather than drug failure.

Patient with 13 chromosome deletion: evidence that the retinoblastoma gene is a recessive cancer gene.

Although a constitutional chromosomal deletion including 13q14 has been found to date in all retinoblastoma patients whose esterase D activity is 50 percent of normal, one female patient has been found who has 50 percent esterase D activity in all normal cells examined but no deletion of 13q14 at the 550-band level. Therefore, she has the smallest constitutional chromosomal deletion within 13q14 that is associated with susceptibility to retinoblastoma. Two stem lines were identified in a retinoblastoma from this patient, and each one had a missing 13 chromosome. No detectable esterase D activity was found in the tumor, indicating that the normal nondeleted 13 chromosome was lost in both stem lines. Thus the data from this patient not only show that there is a total loss of genetic information at the location of the retinoblastoma gene within the tumor, but also imply that recessive genes may play an important role in the development of certain human tumors including retinoblastoma.

Development and acceptability of a video-based vaccine promotion tutorial for obstetric care providers.

A prenatal care provider's recommendation for maternal vaccines is one of the strongest predictors of vaccine acceptance during pregnancy. Aside from basic talking points, few resources exist to help obstetric care providers effectively navigate conversations with vaccine hesitant patients. This paper describes the development and acceptability of "VaxChat," an hour-long, evidence-based video tutorial aimed at improving obstetric care providers' ability to promote maternal vaccines. Between June and November 2017, 62 obstetric care providers registered to receive continuing medical education credit for viewing VaxChat. Of the post-tutorial responses received, over 90% said VaxChat increased their knowledge of what to say to vaccine hesitant patients, increased their confidence in addressing vaccinations with their pregnant patients, and will help them improve their practice culture regarding maternal vaccine promotion. Eighty percent intend to change how they approach vaccine conversations. These data suggest VaxChat may be a welcome complement to existing provider-to-patient talking points.

Temporal trends in baseline characteristics and peri-procedural complications of percutaneous drug-eluting stent implantation for unprotected left main disease: a single high-volume center experience.

AIM: Percutaneous drug-eluting stent (DES) implantation is commonly used in patients with unprotected left main (ULM) disease. As this procedure has been performed routinely in Turin Center since 2002, this article aimed to summarize a five year-experience in DES implantation in the ULM. METHODS: Baseline, procedural and in-hospital outcome data of all patients with ULM undergoing percutaneous coronary intervention (PCI) with DES between July 2002 and October 2006 at Turin Center have been collected. Patients were randomized into four groups: A (patients treated between July 2002 and December 2003), B (treated in 2004), C (treated in 2005) and D (treated in 2006). The baseline surgical risk features was to be compared with the European System for Cardiac Operative Risk Evaluation, disease location in the ULM, and in-hospital major adverse cerebro-cardiovascular events (MACCE), defined as death, myocardial infarction, repeat percutaneous revascularization, coronary artery bypass grafting, stroke, or stent thrombosis. RESULTS: Out of a total of 4 432 coronary interventional procedures 198 patients treated with DES in the ULM were identified. There was a significant increase in the number of patients treated (P=0.00095), but no difference in EuroSCORE across groups (P=0.14). Conversely, there was a significant temporal trend in the incidence of bifurcational ULM being treated with DES (P=0.03). Intriguingly, despite this increase in adverse lesion characteristics, no significant increase was found in the rate of in-hospital MACCE (P=0.93). CONCLUSION: In this single-center study, the number of patients being treated with DES for ULM disease has risen across the years, although keeping a similar surgical risk profile. Distal ULM involvement is no longer considered an absolute contraindication to PCI, as testified by the increasing frequency of such lesion among patients undergoing DES implantation at this Institution, with remarkably low rates of adverse events.

Preferential replication of HIV-1 in the CD45RO memory cell subset of primary CD4 lymphocytes in vitro.

The ability of HIV-1 to establish an infection and replicate to high copy number in CD4 lymphocytes is dependent on both the activation state of the cell and virus-encoded regulatory proteins that modulate viral gene expression. To study these required virus-cell interactions, we have used an in vitro cell model of acute HIV infection of quiescent, primary CD4 lymphocytes and subsequent induction of T cell activation and virus replication by lectin or CD3 receptor cross-linking. Experiments were done to determine if the capacity of HIV to establish infection and complete replication was impacted by the maturational state of the CD4 cell target or the specific signal induction pathway engaged during activation. Primary CD4 cells were FACS-sorted into the major phenotypic subsets representative of memory (CD45RO) and naive (CD45RA) cells. Levels of virus replication were compared between infection with wild-type NL4-3 virus and an isogenic mutant containing a deletion in nef regulatory gene. PHA mitogen stimulation was compared with anti-CD3, with and without anti-CD28 costimulation, for induction of cell proliferation and virus replication. In both infected and uninfected cells, the RA cell subset exhibited significantly greater response to CD3/CD28 stimulation than did the RO cell subset. In contrast, the majority of virus replication occurred consistently in the RO cell subset. Deletion of HIV nef function caused a severe reduction in viral replication, especially in the RA naive cell subset after CD3 induction. PCR analysis of viral DNA formation, during infection of quiescent cells, demonstrated that the observed differences in HIV replication capacity between RO and RA cell subsets were not due to inherent differences in cell susceptibility to infection. Our results indicate that HIV replication is enhanced selectively in CD45RO memory phenotype cells through the probable contribution of specialized cellular factors which are produced during CD3-initiated signal transduction.

Pathogenic and protective correlates of T cell proliferation in AIDS. HNRC Group. HIV Neurobehavioral Research Center.

To investigate the association of antigen specific CD4 T cell activation with HIV disease progression and AIDS-related central nervous system damage, T cell proliferation responses to HIV, CMV, and HSV were evaluated in infected individuals. CD4 T cell loss and neurocognitive impairment were assessed at 6-mo intervals. Individuals with known times of seroconversion who responded to more HIV peptides were at greater risk of progressing to < 200 CD4 T cells (P = 0.04) and dying (P = 0.03) than those with responses to fewer peptides. A positive correlation (0.52) was seen between the breadth of the HIV proliferation response and HIV plasma RNA levels. Higher proliferation responses to CMV and HSV were also associated with more rapid CD4 loss (P = 0.05). HLA phenotyped individuals (n = 150) with two HLA-DR alleles associated with response to more HIV peptides and CMV (DR-2,5,w6,10) were less likely to develop neurocognitive (P = 0.002) and neurologic impairment (P = 0.04), but were not protected from CD4 loss and death. Thus, the ability to generate a greater T cell proliferation response to HIV and opportunistic herpes viruses may lead to resistance to central nervous system damage, but also risk of more rapid HIV disease progression.

Selective vitamin D receptor modulators and their effects on colorectal tumor growth.

The active form of vitamin D, 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], is an endocrine hormone whose classic role is the maintenance of calcium homeostasis. It is well documented that 1,25(OH)(2)D(3) also has anti-tumor effects on a number of cancers and cancer cell lines including breast, colorectal, gastric, liver, ovarian, prostate, and non-melanoma skin cancers. Included in the anti-tumor activities of 1,25(OH)(2)D(3) are its ability to cause antiproliferation, prodifferentation and decrease angiogenesis. Furthermore, through regulation of the plaminogen activator (PA) system and a class of proteolytic enzymes called matrix metalloproteinases (MMPs), 1,25(OH)(2)D(3) reduces the invasive spread of tumor cells. Because of the calcemic limitations of using 1,25(OH)(2)D(3) as a therapy, we have tested the effects of a novel Gemini vitamin D analogue, Deuterated Gemini (DG), on mouse colorectal cancer. We demonstrated that DG is more potent in reducing tumor volume and mass, compared to control and 1,25(OH)(2)D(3). DG significantly prevented (100% reduction, p<0.05) the invasive spread of colorectal tumor cells into the surrounding muscle, and had no effect on serum calcium levels. Thus, DG acts as a selective vitamin D receptor modulator (SVDRM) by enhancing select anti-tumor characteristic 1,25(OH)(2)D(3) activities, without inducing hypercalcemia. Thus, DG shows promise in the development of colorectal cancer therapies.

Vitamin D and cancer.

The correlation between decreased morbidity and mortality of cancer and exposure to sunlight is known. The many biological functions of vitamin D that contribute to cancer prevention have only recently begun to be appreciated. Once activated 1,25-dihydroxyvitamin D [1,25(OH)2D3] functions as a potent inhibitor of normal and cancer cellular proliferation. Vitamin D deficiency in mice led to a 60% increase in colon tumor growth, compared to vitamin D-sufficient mice. The ligand binding domain of the Vitamin D receptor was shown to accommodate a class of 1,25(OH)2D3-analogs that possess an additional side-arm. These novel Gemini analogs were evaluated in vitro and in vivo. Select Gemini analogs were 100 times or more effective in inhibiting colon tumor growth in mice, compared to their parent compound. Correcting vitamin D deficiency may decrease the risk of developing colon cancer, while the novel Gemini 1,25(OH)2D3-analogs have the potential for therapeutic application in human colon cancer.

Suppression of spontaneous in vitro transformation of autologous leukocytes by plasma from convalescent and postconvalescent infectious mononucleosis patients.

All 14 plasma samples from 13 convalescent and postconvalescent infectious mononucleosis (IM) patients suppressed the spontaneous in vitro transformation of autologous leukocytes. In contrast, only 2 of 8 plasma samples from patients with acute IM suppressed this transformation. All 7 patients whose blood was tested both in the acute and convalescent or postconvalescent phases of IM showed either a conversion in transformation suppression status from negative to positive or an increase in the strength of transformation suppression. Thus recovery from IM appeared to be associated with the ability of plasma to suppress the in vitro spontaneous transformation of autologous leukocytes.

Intraperitoneal administration of human recombinant interferon-alpha in patients with ovarian cancer: effects on lymphocyte phenotype and cytotoxicity.

Eleven patients with persistent Stage III ovarian cancer, documented at second look laparotomy, received i.p. human recombinant interferon-alpha (5-50 x 10(6) units/week). Prior to immunotherapy, patients' peritoneal cell lymphocytes (PCLs) contained decreased proportions of Leu-7+ and Fc-receptor+ cells and almost nondetectable natural killer (NK) and antibody-dependent cell cytotoxic (ADCC) activity. In contrast, patients' peripheral blood lymphocytes (PBLs) contained normal proportions of lymphocyte subsets and cytotoxic activity compared to control donor PBLs. During therapy, there was a concurrent increase in PCL Leu-7+ cells and NK lysis. Both peaked predictably at 24 h after each treatment, regardless of the dose injected, and usually returned to baseline by Day 7 of each weekly cycle. PCL NK enhancement was striking, usually increasing from 2-6% (effector:target ratio, 25:1) to over 30% lysis. Enhancement of PCL ADCC was less impressive. PCLs of several patients developed lytic activity towards NK-resistant Raji targets. During therapy, patients' PBLs demonstrated: (a) modestly enhanced NK lysis at Day 4 of each cycle, and; (b) no development of Raji lysis. These data clearly demonstrate the efficacy of i.p. interferon in activation of peritoneal NK activity. However, increased NK lysis did not correlate with individual tumor responses in this cohort of patients.

Depression of the generation of cell-mediated cytotoxicity by macrophage-like suppressor cells in bladder carcinoma patients.

Depressed T-lymphocyte function as assessed by delayed-type hypersensitivity reactions and in vitro proliferative response to mitogens is a characteristic finding in many types of solid tumors, including bladder carcinoma. Peripheral blood leukocytes from 16 patients with transitional cell carcinoma of the bladder were compared with age-matched, control subjects. Both the unfractionated leukocytes containing 10 to 30% monocytes and the lymphocyte-enriched preparations, obtained by monocyte depletion with iron filing ingestion, were analyzed. Mixed leukocyte culture-induced cytotoxicity was depressed in the patient group; the amount of depression was directly correlated to the extent of the disease. In patients who underwent surgical removal of tumor, the mixed leukocyte culture-induced cytotoxicity appeared normal. This mixed leukocyte culture-generated cytotoxic response was a more sensitive indicator of tumor effect than was the induced proliferative response. Removal of phagocytic or adherent monocytes from the responding cell population caused a significant increase in the generated cytotoxicity, especially in those patients with invasive disease. These suppressive effects could be partially reconstituted by quantitative addition of the separated monocytes back to the responding lymphocyte culture. The depressed lymphocyte-mediated cytotoxicity present in these bladder cancer patients was due, in a major part, to a circulating macrophage-like cell with active suppressor function.

Intraperitoneal recombinant alpha-interferon for "salvage" immunotherapy in stage III epithelial ovarian cancer: a Gynecologic Oncology Group Study.

Fourteen patients with persistent epithelial ovarian cancer documented at second look laparotomy after combination chemotherapy were treated with 146 cycles of alpha-recombinant interferon (rIFN-alpha 2) administered i.p. The initial dose was 5 X 10(6) units which was escalated weekly to 50 X 10(6) units over 4 weeks and then continued weekly for a total of 16 weeks. Eleven patients underwent surgical reevaluation after therapy which confirmed four pathological complete responses (36%), one partial response (9%), and disease progression in six patients (55%). Five of seven patients (71%) with residual tumor less than 5 mm had a surgically documented response, whereas there was no response in the four patients whose tumors were greater than or equal to 5 mm. Three patients were evaluable for clinical response only: one patient who refused surgery had a complete clinical response with total resolution of ascites; one had stable disease; and one had disease progression. Fever greater than or equal to 38 degrees C was seen in 58%, fever greater than or equal to 39.0 degrees C was seen in 18%, vomiting in 37%, abdominal pain was reported in 22%, and one patient had infectious peritonitis. Peripheral white blood cell counts and i.p. washings were obtained pretreatment and on days 1, 3, and 7 after treatment. While there was no consistent alteration in peripheral white blood cell counts, the numbers of i.p. monocytes and lymphocytes showed a significant boost on day 1 after each dose of rIFN-alpha 2. Natural killer lymphocyte cytotoxicity was elevated in the i.p. cavity fluid obtained from most patients on day 1 after treatment, while blood natural killer lymphocyte cytotoxicity values showed considerable variability. Pharmacokinetic studies show that i.p. levels of rIFN-alpha 2 were 30-1000 times blood levels. rIFN-alpha 2 i.p. may act by increasing concentrations of drug and augmenting regional host cells in patients with minimal residual ovarian cancer.

Colon cancer and solar ultraviolet B radiation and prevention and treatment of colon cancer in mice with vitamin D and its Gemini analogs.

It has been recognized that people who live at higher latitudes and who are vitamin D deficient are at higher risk of dying from many common cancers including colon cancer. To evaluate the role of vitamin D deficiency on colon tumor growth, Balb/c adult male mice were fed either a vitamin D sufficient or vitamin D deficient diet for 10 weeks. Mice were arranged into groups of six and each animal received subcutaneously 10(4) MC-26 cells in the posterior trunk. The tumor size was recorded daily. By day 9 there was a significant difference in tumor volume between the vitamin D sufficient and vitamin D deficient mice. By day 18 the vitamin D deficient animals had a tumor size that was 56% larger compared to the animals that were vitamin D sufficient. To determine whether treatment with active vitamin D analogs could further decrease colon tumor growth in a vitamin D sufficient state, groups of mice were treated with the novel 19-nor-Gemini compounds. The mice were fed a low calcium diet. Twenty-four hours after tumor implantation, the mice received, three times weekly, one of the vitamin D analogs or the vehicle. The group that received Gemini 1,25-dihydroxy-21(3-hydroxy-3-trifluoromethyl-4-trifluoro-butynyl)-19-nor-20S-cholecalciferol (3) showed a dose-dependent decrease in tumor volume. On day 19, at the dose level of 0.02microg molar equivalents (E), the tumor volume was reduced by 41% when compared to the control group. At the same time point, the hexadeuterated analog 1,25-dihydroxy-21(3-hydroxy-3-trifluoromethyl-4-trifluoro-butynyl)-26,27-hexadeutero-19-nor-20S-cholecalciferol (4), administered at the 10-fold lower dose of 0.002microgE, showed a 52% reduction in tumor volume (p<0.05), compared to the control group. Animals that received 1,25(OH)(2)D(3) at 0.002 and 0.02microg showed a trend in tumor volume reduction at the highest dose but the changes were not statistically significant. An evaluation of serum calcium concentrations revealed that the calcium levels were normal in all groups, except the group receiving 0.02microgE of 4. The results from these studies demonstrate that vitamin D deficiency may accelerate colon cancer growth and that novel Gemini analogs of 1,25(OH)(2)D(3) may be an effective new approach for colon cancer treatment.