Managing sexually transmitted diseases in adolescents

Control of sexually transmitted diseases (STDs) in adolescents is a primary responsibility of health care providers. Using the tools of history and physical examination, and drawing on the awareness of different stages of adolescent development, health care providers can define at-risk for STDs. This article discusses screening practices, disease control through reporting and preventive counseling, and treatment guidelines for common STD syndromes.     

Fas (CD95/Apo-1)-mediated damage to ventricular myocytes induced by cytotoxic T lymphocytes from perforin-deficient mice: a major role for inositol 1,4,5-trisphosphate

Cytotoxic T lymphocytes (CTLs) that infiltrate the heart are important immune effectors implicated in heart transplant rejection, myocarditis, and other cardiomyopathies. To investigate the mechanism(s) underlying CTL damage to the myocardium through activation of the Fas receptor (Fas/CD95/Apo-1) by the Fas ligand, we explored the interaction between peritoneal exudate CTLs (PELs), derived from perforin gene-knockout (P-/-) mice, and murine ventricular myocytes. Fas expression on isolated ventricular myocytes was demonstrated immunohistochemically. Action potentials, [Ca2+]i transients, and contractions of myocytes conjugated to P-/- PELs or treated with the apoptosis-inducing anti-Fas monoclonal antibody Jo2 were recorded. Action potential characteristics of nonconjugated myocytes and myocytes conjugated with P-/- PELs were, respectively, as follows: Vm, -73.2+/-1.5 and -53.6+/-6.4 mV (mean+/-SEM); action potential amplitude, 117.9+/-3.9 and 74.3+/-21.2 mV; and action potential duration at 80% repolarization, 17+/-6 and 42+/-13 milliseconds (all P<.05). P-/- PELs also induced early and delayed afterdepolarizations as well as arrhythmogenic activity. Diastolic [Ca2+]i increased during the cytocidal interaction with P-/- PELs, from a fluorescence ratio of 0.82+/-0.05 (n=7) to 1.98+/-0.09 (n=13) (P<.05). All of the effects caused by P-/- PELs were reproduced by incubating the myocytes with Jo2. Heparin (50 microg/mL), an antagonist of inositol trisphosphate (IP3)-operated sarcoplasmic reticulum Ca2+ channels, or U-73122 (2 micromol/L), a phospholipase C inhibitor, but not the inactive agonist U-73343, prevented Fas-mediated myocyte dysfunction. Additionally, intracellular application (through the patch pipette) of the active IP3 analogue, inositol 1,4,5-trisphosphate, but not the inactive analogue, inositol 1,3,4-trisphosphate, caused electrophysiological changes resembling those resulting from P-/- PELs and Jo2, suggesting that CTL-induced Fas-based myocyte dysfunction is mediated by IP3. We conclude that a Fas-based perforin-independent mechanism of CTL action can account for the immunopathology seen in the allotransplanted heart, myocarditis, and dilated cardiomyopathy.     

Primary muscle lymphoma: clinical and imaging findings

PURPOSE: To assess the clinical and imaging findings in primary muscle lymphoma. MATERIALS AND METHODS: Seven patients with biopsy-proved primary muscle lymphoma without evidence of systemic disease underwent imaging with plain radiography or computed tomography (CT) and magnetic resonance (MR) imaging. Four underwent bone scintigraphy, and two underwent gallium scintigraphy and fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) before and after therapy. RESULTS: Plain radiographs at initial examination (n = 5) showed no bone abnormalities. Soft-tissue masses and bone marrow involvement showed isoattenuation at CT (n = 3), but at MR imaging (n = 7), all masses demonstrated increased signal intensity on T2-weighted images that involved multiple muscle compartments and typically spanned a long segment of the extremity. Adjacent bone disease was less extensive than muscle disease, and, in most cases, subcutaneous stranding or extension was observed adjacent to the masses. Good size correlation was observed between findings at MR imaging, gallium scintigraphy, and FDG PET. Two patients developed recurrent multifocal muscle lymphoma several years after initial examination. CONCLUSION: The presence of an extensive soft-tissue mass with infiltration of adjacent subcutaneous fat and minimal or no extension into the bone marrow cavity at MR imaging and normal plain radiographic findings may suggest primary muscle lymphoma.     

Breast cancer screening programmes in 22 countries: current policies, administration and guidelines. International Breast Cancer Screening Network (IBSN) and the European Network of Pilot Projects for Breast Cancer Screening

BACKGROUND: Currently there are at least 22 countries worldwide where national, regional or pilot population-based breast cancer screening programmes have been established. A collaborative effort has been undertaken by the International Breast Cancer Screening Network (IBSN), an international voluntary collaborative effort administered from the National Cancer Institute in the US for the purposes of producing international data on the policies, funding and administration, and results of population-based breast cancer screening. METHODS: Two surveys conducted by the IBSN in 1990 and 1995 describe the status of population-based breast cancer screening in countries which had or planned to establish breast cancer screening programmes in their countries. The 1990 survey was sent to ten countries in the IBSN and was completed by nine countries. The 1995 survey was sent to and completed by the 13 countries in the organization at that time and an additional nine countries in the European Network. RESULTS: The programmes vary in how they have been organized and have changed from 1990 to 1995. The most notable change is the increase in the number of countries that have established or plan to establish organized breast cancer screening programmes. A second major change is in guidelines for the lower age limit for mammography screening and the use of the clinical breast examination and breast self-examination as additional detection methods. CONCLUSION: As high quality population-based breast cancer screening programmes are implemented in more countries, they will offer an unprecedented opportunity to assess the level of coverage of the population for initial and repeat screening, evaluation of performance, and, in the longer term, outcome of screening in terms of reduction in the incidence of late-stage disease and in mortality.     

Maternal supplementation with cobalt sources,folic acid,and rumen-protected methionine and its effects on molecular and functional correlates of the immune system in neonatal Holstein calves

Calves born to multiparous Holstein cows fed during the last 30 d of pregnancy 2 different cobalt sources [cobalt glucoheptonate (CoPro) or cobalt pectin (CoPectin)], folic acid (FOA), and rumen-protected methionine (RPM) were used to study neonatal immune responses after ex vivo lipopolysaccharide (LPS) challenge. Groups were (n = 12 calves/group) CoPro, FOA+CoPro, FOA+CoPectin, and FOA+CoPectin+RPM. Calves were weighed at birth and blood collected at birth (before colostrum), 21 d of age, and 42 d of age (at weaning). Growth performance was recorded once a week during the first 6 wk of age. Energy metabolism, inflammation, and antioxidant status were assessed at birth through various plasma biomarkers. Whole blood was challenged with 3 µg/mL of LPS or used for phagocytosis and oxidative burst assays. Target genes evaluated by real-time quantitative PCR in whole blood samples were associated with immune response, antioxidant function, and 1-carbon metabolism. The response in mRNA abundance in LPS challenged versus nonchallenged samples was assessed via Δ = LPS challenged ? LPS nonchallenged samples. Phagocytosis capacity and oxidative burst activity were measured in neutrophils and monocytes, with data reported as ratio (percentage) of CD14 to CH138A-positive cells. Data including all time points were subjected to ANOVA using PROC MIXED in SAS 9.4 (SAS Institute Inc.), with Treatment, Sex, Age, and Treatment × Age as fixed effects. A 1-way ANOVA was used to determine differences at birth, with Treatment and Sex as fixed effects. Calf birth body weight and other growth parameters did not differ between groups. At birth, plasma haptoglobin concentration was lower in FOA+CoPro compared with CoPro calves. We detected no effect for other plasma biomarkers or immune function due to maternal treatments at birth. Compared with CoPro, in response to LPS challenge, whole blood from FOA+CoPectin and FOA+CoPectin+RPM calves had greater mRNA abundance of intercellular adhesion molecule 1 (ICAM1). No effect for other genes was detectable. Regardless of maternal treatments, sex-specific responses were observed due to greater plasma concentrations of haptoglobin, paraoxonase, total reactive oxygen metabolites, nitrite, and β-carotene in female versus male calves at birth. In contrast, whole blood from male calves had greater mRNA abundance of IRAK1, CADM1, and ITGAM in response to LPS challenge at birth. The longitudinal analysis of d 0, 21, and 42 data revealed greater bactericidal permeability-increasing protein (BPI) mRNA abundance in whole blood from FOA+CoPectin versus FOA+CoPro calves, coupled with greater abundance in FOA+CoPro compared with CoPro calves. Regardless of maternal treatments, most genes related to cytokines and cytokine receptors (IL1B, IL10, TNF, IRAK1, CXCR1), toll-like receptor pathway (TLR4, NFKB1), adhesion and migration (ICAM1, ITGAM), antimicrobial function (MPO), and antioxidant function (GPX1) were downregulated over time. Phagocytosis capacity and oxidative burst activity in both neutrophils and monocytes did not differ due to maternal treatment. Regardless of maternal treatments, we observed an increase in the percentage of neutrophils capable of phagocytosis and oxidative burst activity over time. Overall, these preliminary assessments suggested that maternal supplementation with FOA and Co combined with RPM had effects on a few plasma biomarkers of inflammation at birth and molecular responses associated with inflammatory mechanisms during the neonatal period.     

The Radiolytic Isomerization of Stilbene in Solid Systems

The γ-ray induced trans → cis isomerization of stilbene was investigated in solutions in the frozen organic solvents benzene, toluene, naphthalene, dibenzyl, and cyclohexane, and compared with fluid solutions in the same solvents, at appropriate temperatures. In dilute (up to 10^?3M) solutions in benzene isomerization takes place in the frozen system at a higher rate than in the corresponding fluid system, with the ratio between these rates increasing with decreasing stilbene concentration. These results indicate that energy transfer in frozen benzene, and to stilbene embedded in it, takes place by a more efficient mechanism than the diffusional one operative in fluid solutions. It is suggested that singlet or triplet excitons are responsible for energy transfer within the microcrystals of the frozen benzene, and to stilbene molecules situated in specific (possibly surface) sites. At stilbene concentrations in the range 5 × 10^?5 to 10^?1M G(trans → cis) in the frozen solutions is approximately constant (? 0.7), corresponding to G(excited stilbene) ? 1.4. This result is compatible with a mechanism involving efficient “harvesting” of all triplet benzene molecules in the solid under these conditions. Dilute solutions in toluene behave in a similar way, but no radiolytic isomerization takes place in solutions in solid naphthalene or dibenzyl, and also not in solid trans stilbene.     

Ultrasonic evaluation of the vitreous and retina

Ultrasonic evaluation of the vitreous body augments and complements visual and clinical assessment in any condition in which some form of media opacity exists, eg, cornea, lens, hemorrhage, or subretinal mass. The appearance of the eye in hypotony, the presence of foreign material, the pattern of hemorrhage, and the presence of a detached retina or choroid are all identifiable and their diagnosis may be of critical importance to patient management. Patterns of diabetic retinopathy and ocular tumors are usually characteristic using conventional 10 MHz ultrasound. The use of Very High Frequency (VHF or UBM) ultrasound can identify ciliary body detachment or other retroiridal pathology, such as tumors and cysts.