Recombinant vaccinia viruses expressing GP46/M-2 protect against Leishmania infection.

Leishmania is a genus of parasitic protozoa capable of causing a spectrum of human diseases. The GP46/M-2 membrane glycoprotein has been demonstrated in a murine model system to elicit a protective immune response against infection with Leishmania amazonensis; in highly susceptible BALB/c mice, immunization leads to significant protection against infection. In the present study, for induction of long-term immunological effects, two recombinant vaccinia viruses, derived from the wild type and attenuated variant 48-7 and expressing the GP46/M-2 protein, were constructed; to ensure safety, we used the attenuated vaccinia virus mutant (48-7) as a live vector. Susceptible BALB/c mice immunized with either GP46/M-2-recombinant vaccinia virus were significantly protected against infection with L. amazonensis; 45 to 76% of the animals were completely protected (sterile) against a challenge inoculum of 10(3) infective organisms. The protectively immunized animals demonstrated T- and B-cell-dependent immunological responses; both lymphokine responses as well as antibody responses and long-term memory are indicative of T-cell activation. This first report of the use of a recombinant vaccinia virus to induce protection against a Leishmania infection indicates that recombinant vaccinia viruses should be of value in the design of a safe and effective vaccine against this parasitic disease.     

CD28-dependent killing by human YT cells requires phosphatidylinositol 3-kinase activation

CD28/B7 interactions have been demonstrated to provide a co-stimulatory signal for the generation of CD8⁺ cytotoxic T lymphocytes in the absence of CD4⁺ T helper cells. The CD28 signals required for induction of cytotoxicity have yet to be described. To investigate further the biochemical signaling pathways associated with CD28-dependent cytotoxicity, we have studied the human thymic leukemia cell line, YT. YT cells kill B7⁺ targets in a non-major histocompatibility complex (MHC)-restricted, CD28-dependent manner. CD28 ligation on the surface of YT cells caused a rapid increase in the tyrosine phosphorylation of four major cellular substrates with masses estimated to be 110, 95, 85, and 44 kDa. The 110 and 85 kDa substrates were identified as the catalytic and regulatory subunits, respectively, of phosphatidylinositol 3-kinase (PI3-K). Engagement of CD28 caused the rapid receptor association and activation of PI3-K but did not activate phospholipase C_γ. CD28-induced tyrosine phosphorylation and PI3-K activation was independent of p56^lck protein tyrosine kinase (PTK) activity (previously reported to be associated with CD28) and was insensitive to inhibition by the PTK inhibitor herbimycin A. Two structurally and mechanistically dissimilar inhibitors of PI3-K, wortmannin and 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002) also failed to block CD28-dependent tyrosine phosphorylation events or the association of PI3-K with the CD28 receptor. However, both drugs inhibited CD28-dependent cytotoxicity and CD28 receptor associated PI3-K activity with IC₅₀ values similar to the reported IC₅₀ values for PI3-K inhibition. Although herbimycin A did not significantly block the observed CD28-dependent tyrosine phosphorylation or PI3-K activation, herbimycin did block CD28-dependent cytotoxicity in a dose-dependent manner. These data support a role for PI3-K activation in the CD28-dependent initiation of cytotoxic effector function and suggest that a herbimycin sensitive step(s) is either CD28-independent, resides within a PI3-K-independent CD28 signaling pathway, or is downstream of CD28-dependent PI3-K activation.     

Determination of isotretinoin or etretinate and their major metabolites in human blood by reversed-phase high-performance liquid chromatography

A method is described for the quantitative analysis of isotretinoin and its 4-oxo metabolite, or of etretinate and its principal metabolites, in human blood in the range 10-2000 ng/ml. Following a simple one-step extraction, the compounds are determined by reversed-phase high-performance liquid chromatography (HPLC) with gradient elution and detection at 365 nm. This highly specific method separates the cis and trans isomers of the parent compounds and their metabolites. Examples are given of the application of this method to clinical studies of these two therapeutically important retinoids.     

High-dose induction chemotherapy of metastatic breast cancer in protected environment: a prospective randomized study

To test the hypothesis of whether high doses of chemotherapy in combination achieve higher response rates and longer durations of response and survival, we treated 33 pre- and perimenopausal patients with good performance status in a prospective trial with escalating doses of fluorouracil, doxorubicin and cyclophosphamide (FAC). Patients were randomly assigned to be treated within a protected environment (laminar air flow room), with prophylactic antibiotics, or in a standard hospital room. Important patient characteristics were equally distributed in the two treatment arms. A major objective response was observed in 27 of the 32 evaluable patients (84%), and 11 (34%) achieved a complete remission (CR). There was no significant difference in overall and complete response rates between the two treatment arms, nor was there a substantial difference in times to progression or survival between the groups treated in or out of the protected environment. Comparison of the results of this study with previously reported programs of FAC chemotherapy in patients with metastatic breast cancer shows that this study achieved higher overall and complete response rates. However, neither the time to progression, nor the survival of responders or the entire patient group was different from our previous experience with standard FAC chemotherapy. When the study was initiated in 1976, the proposed dose escalation represented high-dose chemotherapy. In retrospect, even the "high" doses used in this study represent only a modest increase over standard doses of chemotherapy. Much steeper dose escalations will be needed to evaluate the efficacy of high-dose chemotherapy in breast cancer, as well as the protective value of the protected environment and prophylactic antibiotics in metastatic breast cancer.     

Esophageal electrocardiography: a new technology revives an old technique

This study evaluates the clinical use of an easily swallowed bipolar electrode for recording an esophageal electrocardiogram (ECG). Fourteen patients were selected for bedside diagnosis (ECG group) because of arrhythmias difficult to evaluate using a standard 12-lead ECG. A second group of 27 non-selected patients scheduled for routine 24-hour ambulatory electrocardiographic recordings (ambulatory ECG group) had an esophageal ECG recorded as the "third channel." All 14 patients (100%) in the ECG group had excellent-quality tracings, and the esophageal ECG was diagnostic in 12 cases (86%). Of 27 patients in the ambulatory ECG group, 19 (70%) had fairly good to excellent-quality 24-hour esophageal pill tracings, with the esophageal ECG contributing to correct arrhythmia diagnosis in 11 patients (41%). It is concluded that this easily swallowed esophageal electrode provides an excellent-quality short-term ECG and often permits proper arrhythmia diagnosis in selected patients with arrhythmias. Good-quality 24-hour esophageal ambulatory electrocardiographic recordings can also be obtained that contribute to arrhythmia diagnosis in a limited number of unselected patients, and should be even more clinically useful in carefully selected patients.     

HPLC analysis of valepotriates in the north american genera plectritis and valeriana

Reversed phase HPLC has been applied to the isolation and quantitative distribution of valepotriates in roots and aerial parts of species and subspecies of the North American Genus PLECTRITIS (Valerianaceae) and in VALERIANA SITCHENSIS ssp. SCOULERI (Valerianaceae). A semipreparative Ultrasphere ODS column was used for separation and detection of small quantities of valepotriates in crude plant extracts.     

Rapid,Full-Scale Change to Virtual PCIT During the COVID-19 Pandemic: Implementation and Clinical Implications

Health agencies call for the immediate mobilization of existing interventions in response to numerous child and family mental health concerns that have arisen as result of the COVID-19 pandemic. Answering this call, this pilot study describes the rapid, full-scale change from a primarily clinic-based Parent–Child Interaction Therapy (PCIT) model to a virtual service model (i.e., I-PCIT) in an academic and community-based program in Miami, Florida. First, we describe the virtual service training model our program developed and its implementation with 17 therapists (M_Age?=?32.35, 88.2% female, 47.1% Hispanic) to enable our clinic to shift from providing virtual services to a small portion of the families served (29.1%) to all of the families served. Second, we examine the effect of I-PCIT on child and caregiver outcomes during the 2-month stay-at-home period between March 16, 2020, and May 16, 2020, in 86 families (M_ChildAge?=?4.75, 71% Hispanic). Due to the rapid nature of the current study, all active participants were transferred to virtual services, and therefore there was no comparison or control group, and outcomes represent the most recently available scores and not treatment completion. Results reveal that I-PCIT reduced child externalizing and internalizing problems and caregiver stress, and increased parenting skills and child compliance with medium to large effects even in the midst of the COVID-19 pandemic. Finally, the study examined components of our virtual service training model associated with the greatest improvements in child and caregiver outcomes. Preliminary findings revealed that locally and collaboratively developed strategies (e.g., online communities of practice, training videos and guides) had the strongest association with child and caregiver outcomes. Implications for virtual service delivery, implementation, and practice in the midst of the COVID-19 pandemic are discussed.

     

Correction to: Health Literacy Within a Diverse Community-Based Cohort: The Multi-Ethnic Study of Atherosclerosis

Journal of Immigrant and Minority Health - The original version of this article unfortunately contained a typo in co-author name.