Patient satisfaction with the Veteran's Administration teledermatology service.

BACKGROUND: Teledermatology is comparable to face-to-face visits in providing accurate diagnoses and effective treatments. However, there are limited data regarding patient satisfaction with teledermatology models that more directly convey provider recommendations to patients. OBJECTIVE: To assess patient satisfaction with the teledermatology service at the Atlanta Veterans Affairs Medical Center (AVAMC). METHODS: A cross-sectional, phone-based questionnaire study of 175 AVAMC teledermatology patients was performed to investigate patient satisfaction. In phase 1 (n = 100), we compared the teleconsultative and telemedicine models. In phase 2 (n = 75), we compared patients who received 1 of 3 possible consult outcomes: reassurance, appointment for biopsy, or appointment for face-to-face evaluation. RESULTS: There were no statistically significant differences in satisfaction between patients who were seen with the telemedicine and teleconsultative models. Patients who received appointments for face-to-face evaluation or biopsy were more satisfied than patients who received reassurance only. Both phases were remarkable for high patient satisfaction among all cohorts. LIMITATIONS: This study was performed at a single Veterans Affairs medical center and is vulnerable to both nonresponse bias and recall bias. CONCLUSION: Overall, patients are satisfied with teledermatology services at the AVAMC. Strong partnership with referring primary care providers and clear delineation of responsibilities is vital to the teledermatology process.

Phospholipid Ether Linkages Significantly Modulate the Membrane Affinity of the Antimicrobial Peptide Novicidin.

The biological activity of antimicrobial peptides is believed to be closely linked to their ability to perturb bacterial membranes. This makes it important to understand the basis of their membrane-binding properties. Here, we present a biophysical analysis of the interactions of the antimicrobial peptide Novicidin (Nc) with ether- and ester-linked C14 phospholipid vesicles below and above the lipid phase transition temperature (t p). These interactions are strongly dependent on whether the lipids contain ether or ester linkages. Nc is in random coil state in solution but undergoes a large increase in α-helicity in ether vesicles, and to a much smaller extent in ester vesicles, around the t p. This structure is lost at higher temperatures. Steady-state fluorescence and stopped-flow kinetics using fluorophore-labeled Nc reveal that Nc binds more strongly to ether vesicles than to ester vesicles below the t p, while there is no significant difference above the t p. This may reflect ether lipid interdigitation in the gel phase. Isothermal titration calorimetry reveals that partitioning of Nc into both lipids is exothermic and thus enthalpy driven. The higher enthalpy associated with binding to ether lipid may be linked to Nc's higher propensity to form α-helical structure in this lipid. The large effect of the ether-ester interchange reveals that membrane-AMP interactions can be strongly modulated by charge-neutral head group changes.

Novicidin's membrane permeabilizing activity is driven by membrane partitioning but not by helicity: a biophysical study of the impact of lipid charge and cholesterol.

We have investigated the interactions between the antimicrobial peptide Novicidin (Nc) and vesicles containing the phospholipid DOPC, with various amounts of DOPG and cholesterol using circular dichroism spectroscopy, calcein release, equilibrium dialysis and isothermal titration calorimetry. Nc adopts a random coil structure in the absence of lipids and in the presence of vesicles containing 100% DOPC. Lipids with 25-40% DOPG induce the highest level of helicity in Nc; higher DOPG levels lead to lower helicity levels and an altered tertiary arrangement of the peptide. However, the ability of Nc to permeabilize vesicles correlates not with helicity but rather with its overall membrane affinity, which is enthalpically favorable but opposed by entropy. Permeabilization declines with increasing mole percentage PG. Changes in helicity correlate with changes in enthalpy, reflecting the enthalpy of helix formation, but not with affinity. There is also a large favorable enthalpic interaction between Nc and lipids in the absence of negative charge and structural changes. Cholesterol slightly reduces membrane permeabilization but has little effect on Nc affinity and secondary structure, and probably protects the membrane by inducing the liquid ordered state. We conclude that helicity is not a prerequisite for activity, and charge-charge interactions are not the only major driving force for AMP interactions with membranes. Our data are compatible with a model in which a superficial binding mode with a large membrane surface binding area per peptide is more efficient than a more intimate embedding within the membrane environment.

Soft interactions at nanoparticles alter protein function and conformation in a size dependent manner.

Weak protein-nanoparticle (NP) interactions are studied in a low binding regime as a model for the soft protein corona around nanoparticles in complex biological fluids. Noncovalent, reversible interactions between Subtilisin Carlsberg (SC) and silica NPs shows significant alteration in conformation and enzymatic activity in a NP-size dependent manner. Very weak interactions between SC and silica NPs were revealed by centrifugation-based separations and further supported by small-angle X-ray scattering, while bovine serum albumin was used as a strongly interacting reference. Secondary and tertiary structure changes of SC were studied via circular dichroism and correlated to enzymatic activity where the enzyme kinetics showed a critical role for nanoparticle size.

Does left ventricular diastolic function deteriorate earlier than left ventricular systolic function in anthracycline cardiotoxicity?

Cardiotoxicity is the most important complication in patients receiving anthracycline chemotherapy. We studied the left ventricular diastolic function (LVDF) and systolic function (LVSF) in these patients and assessed whether LVDF deteriorates earlier than LVSF. We prospectively studied 58 patients (mean age 48.02 ± 13.87; 32 female, 26 male) on anthracycline treatment, before chemotherapy (S0) and after cumulative doses of 139 ± 12 mg/m(2) (S1) and 308 ± 14 mg/m(2) (S2). The LVSF was computed in terms of left ventricular ejection fraction (LVEF) from equilibrium radionuclide angiography (ERNA). The peak ejection rate (PER), peak filling rate (PFR), time to peak ejection rate (TPER), time to peak filling rate (TPFR), 1/3rd filling fraction and ratio of PFR and PER were calculated from ERNA and were also standardized using 150 baseline ERNA studies. Statistical analysis was done by repeated measures analysis of variance (ANOVA). We found significant decrease in LVEF (P<0.001) and PER (P<0.001) between the S1 and S2 studies and PFR (P<0.007) between the S0 and S1 studies. In conclusion in patients receiving anthracycline treatment, LVDF deteriorates earlier than left ventricular systolic function (LVSF).

Risk of Skin Cancers in Older Persons Living With HIV: A Systematic Review.

Skin cancers-including basal cell carcinoma, squamous cell carcinoma, and melanoma-impose high incidence and morbidity in older persons. As life expectancy continues to increase in persons living with HIV (PLWH), this population may face an increased risk of non-AIDS-defining malignancies, such as skin cancers. We conducted a systematic review on skin cancer risks in PLWH, ages 50 years or older, as compared with age-matched, HIV-uninfected persons. Four studies met criteria and were included. No statistically significant associations were demonstrated between HIV infection and skin cancers in older persons. For those with a history of basal or squamous cell carcinoma, HIV infection was associated with higher risks of subsequent squamous cell carcinoma. Future studies are needed to elucidate and reduce morbidity of primary and multiple skin cancers to promote successful aging in PLWH.

Disseminated tuberculosis masquerading as metastatic breast carcinoma on PET-CT.

PET has an established role in the management of breast cancer. However, F-18 FDG uptake sometimes has been associated with benign disease leading to false positive results. We present a case of a 37-year-old woman who presented with a 3-month history of a left breast lump and palpable left axillary lymph nodes. Whole-body PET-CT scan demonstrated multiple focal areas of intense FDG uptake in the left breast and multiple axillary, cervical, and mediastinal lymph nodes. PET-CT findings mimicked metastatic breast cancer, which was subsequently confirmed as disseminated tuberculosis by mammotome-guided biopsy of the breast lesion and fine needle aspiration biopsy of lymph nodes.

Hepatobiliary scintigraphy in detecting lesser sac bile leak in postcholecystectomy patients: the need to recognize as a separate entity.

Cholecystectomy is one of the most commonly performed abdominal surgeries in which bile duct injury and bile leaks are the most important complications. Imaging plays an important role in the prompt diagnosis and management of bile leaks. The more common sites of bile leak are the gallbladder bed, subhepatic, in a bilioma, right paracolic gutter, or diffusely in the peritoneal cavity. Bile leak into the lesser sac (LS) is uncommon but is a special entity posing difficult problems in management. We have described in this study the clinical presentation, imaging findings, and management of 6 patients with biliary leakage into the LS postcholecystectomy. The clinical presentation of this condition was varied, ranging from patients with asymptomatic or with vague complaints resulting in difficulties in clinical suspicion or symptomatic but minimal enough not to be detected by ultrasonogram. Hepatobiliary scintigraphy played an important role in the diagnosis and management, and all patients required definitive therapeutic drainage procedures. Any persistent focal radiotracer activity in the anatomy of the LS, increasing with time and not diffusing into the general peritoneal cavity is diagnostic of bile leak into the LS.