Environmental Nonadditivity and Franck-Condon physics in Nonequilibrium Quantum Systems.

We show that for a quantum system coupled to both vibrational and electromagnetic environments, enforcing additivity of their combined influences results in nonequilibrium dynamics that does not respect the Franck-Condon principle. We overcome this shortcoming by employing a collective coordinate representation of the vibrational environment, which permits the derivation of a nonadditive master equation. When applied to a two-level emitter our treatment predicts decreasing photon emission rates with increasing vibrational coupling, consistent with Franck-Condon physics. In contrast, the additive approximation predicts the emission rate to be completely insensitive to vibrations. We find that nonadditivity also plays a key role in the stationary nonequilibrium model behavior, enabling two-level population inversion under incoherent electromagnetic excitation.

Biomarkers in retinopathy of prematurity: a systematic review and meta-analysis.

Aim: Retinopathy of prematurity is a significant global cause of childhood blindness. This study aims to identify serum biomarkers that are associated with the development of ROP. Methods: A systematic review and meta-analysis was conducted using PRISMA guidelines. Three databases were searched (Pubmed, Scopus and Web of Science) from 2003 to March 2023. Only studies investigating serum biomarker levels in preterm infants (<37 weeks gestation) were included. Results: Meta-analysis suggests that low serum IGF-1 levels have a strong association with the development of ROP [SMD (95% CI) of -.46 [-.63, -.30], p < .001]. Meta-analysis suggests that higher serum glucose levels were associated with the development of ROP [SMD (95% CI) of 1.25 [.94, 1.55], p < .001]. Meta-analysis suggests that thrombocytopenia is associated with the development of ROP [SMD (95% CI) of -.62 [-.86, -.37], p < .001]. Conclusion: Low levels of serum IGF-1, high levels of serum glucose and thrombocytopenia all appear to have the strongest association with the development of ROP out of the 63 biomarkers investigated in this review. These associations highlight their potential use as diagnostic biomarkers in ROP, though further research is needed to establish the exact relationship between these biomarkers and disease pathogenesis.

Adenovirus encoding HIV-1 Vpr activates caspase 9 and induces apoptotic cell death in both p53 positive and negative human tumor cell lines.

The targeted delivery of genes whose products arrest the cell cycle and/or induce apoptosis represent an important tool for the understanding and controlling forms of unregulated cell growth. The vpr gene product of HIV-1 has been reported to interfere with cell growth and induce apoptosis, but the mechanism of its action is not clearly understood. In order to study these important properties of Vpr, we created a recombinant adenovirus H5.010CMV-vpr (adCMV-vpr) as a tool to deliver the vpr gene to various cell lines to examine its biology. Vpr protein expression was confirmed by Western blot analysis in adCMV-vpr infected cells. We tested the effects of adCMV-vpr on cell growth of several tumor cell lines. Infection of both p53 positive and p53 deficient tumor cell lines with adCMV-vpr resulted in dramatic induction of cell death in short-term assays. We observed that apoptosis was induced through the mitochondrial pathway as we observed changes in the cytochrome c content accompanied by caspase 9 activation. As Bcl-2 is reported to interfere with apoptosis through the mitochondrial pathway, we examined the effect of adCMV-vpr in Bcl-2 over expressing cell lines. We observed that Bcl-2 overexpression does not inhibit adCMV-vpr induced apoptosis. The properties of adCMV-vpr inducing apoptosis through caspase 9 in a p53 pathway independent manner suggest that this is an important reagent. Such a vector may give insight into approaches designed to limit the growth of pathogenic human cells.

Immunopharmacologic analysis of an autologous, hapten-modified human melanoma vaccine.

PURPOSE: We have previously reported a clinical trial of a human cancer vaccine consisting of autologous tumor cells modified with the hapten, dinitrophenyl (DNP), in patients with clinical stage III melanoma. Here we present a follow-up report expanded to 214 patients with 5-year follow-up. PATIENTS AND METHODS: Two hundred fourteen patients with clinical stage III melanoma (117 patients with stage IIIC and 97 patients with stage IIIB) who were melanoma-free after standard lymphadenectomy were treated with multiple intradermal injections of autologous, DNP-modified vaccine mixed with bacille Calmette-Guérin. Four vaccine dosage schedules were tested sequentially, all of which included low-dose cyclophosphamide. Patients were tested for delayed-type hypersensitivity (DTH) to autologous melanoma cells, both DNP-modified and unmodified, and to control materials. RESULTS: The 5-year overall survival (OS) rate of the 214 patients was 44%. DTH responses to unmodified autologous melanoma were induced in 47% of patients. The OS of this DTH-positive group was double that of DTH-negative patients (59.3% v 29.3%; P <.001). In contrast, positive DTH responses to DNP-modified autologous melanoma cells and to purified protein derivative developed in almost all patients but did not affect OS. Surprisingly, the OS after relapse was also significantly longer in patients who developed positive DTH to unmodified tumor cells (25.2% v 12.3%; P <.001). Finally, the development of DTH was dependent on the schedule of administration of the vaccine, specifically, the timing of an induction dose administered at the beginning of the treatment program. CONCLUSION: This study underscores the importance of the immunopharmacology of the autologous, DNP-modified vaccine and may be relevant to other cancer vaccine technologies.

Analytical and biological characterization of supercoiled plasmids purified by various chromatographic techniques.

Supercoiled plasmids are an important component of gene-based delivery vehicles. A number of production methods for clinical applications have been developed, each resulting in very high-quality product with low levels of residual contaminants. There is, however, no consensus on the optimal methods to characterize plasmid quality, and further, to determine if these methods are predictive of either product stability or biological activity. We have produced two plasmids using four production purification methodologies based on PolyFlo and hydrophobic interaction chromatography (HIC), either alone or in tandem processes. In each case, the product was analyzed using standard molecular biological methods. We also performed a number of biophysical analyses such as dynamic light scattering (DLS), circular dichroism (CD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Minimal differences were detected among the preparations based on the more standard molecular biological methods. Some small differences were detected, however, using biophysical techniques, particularly FTIR and DSC, which may reflect small variations in plasmid tertiary structure and thermal stability. Stability after heat exposure at 60 degrees C, exposure to fetal bovine serum and long-term storage at 4 degrees C varied between plasmids. One plasmid showed no difference in stability depending on the production process, but the other showed significant differences. Evaluation in vivo in models for gene immunization and gene therapy showed significant differences in the response depending on the method of purification. Preparations using a tandem process of PolyFlo used in two separation modes provided higher biological activity compared to a tandem HIC/PolyFlo process or either resin used alone in a single column process. These data indicate that the process by which supercoiled plasmids are made can influence plasmid stability and biological activity and emphasize the need for more rigorous methods to evaluate supercoiled plasmids as gene-delivery vehicles.

Plasmid immunization primes unique DTH responses to HIV-1MN envelope epitopes as compared to recombinant protein vaccination.

Current evidence suggests that the induction of cell-mediated immunity is required for a successful HIV-1 vaccine. Delayed type hypersensitivity (DTH) and cellular cytotoxicity are closely linked elements of the cellular immune response, both are favored by immunizations that result in a T-helper (Th)-1 response. The classical experimental animal for the study of DTH is the guinea pig. Here we report that guinea pigs can readily be sensitized for DTH skin reactions to envelope protein with a plasmid expressing HIV-1(MN) (subtype B) envelope, as well as with the recombinant HIV-1 envelope protein. Further, utilizing peptide probes that in aggregate represent the entire gp120 molecule, common and unique dominant epitopes induced by each method of immunization were identified.

Monoclonal anti-idiotypic antibody mimicking the gastrointestinal carcinoma-associated epitope CO17-1A elicits antigen-specific humoral and cellular immune responses in colorectal cancer patients.

Monoclonal rat anti-idiotypic antibody (Ab2) BR3E4 mimicking the colorectal carcinoma (CRC)-associated epitope CO17-1A induced antigen-specific humoral and cellular immune responses in mice and rabbits. Ab2 BR3E4 was administered in a phase I trial to CRC patients either as intact IgG or as F(ab')(2) coupled to keyhole limpet hemocyanin (KLH). There was a trend for the F(ab')(2)-KLH-immunized patients to show higher immune response rates (18/21 and 5/15 patients with anti-anti-idiotypic antibodies and T cells, respectively) than the IgG-immunized patients (15/23 and 3/15 patients positive). Clinical responses were rare in these patients with liver metastases.