Cellulose nanofibrils prepared by gentle drying methods reveal the limits of helium ion microscopy imaging.

TEMPO-oxidized cellulose nanofibrils (TCNFs) have unique properties, which can be utilised in many application fields from printed electronics to packaging. Visual characterisation of TCNFs has been commonly performed using Scanning Electron Microscopy (SEM). However, a novel imaging technique, Helium Ion Microscopy (HIM), offers benefits over SEM, including higher resolution and the possibility of imaging non-conductive samples uncoated. HIM has not been widely utilized so far, and in this study the capability of HIM for imaging of TCNFs was evaluated. Freeze drying and critical point drying (CPD) techniques were applied to preserve the open fibril structure of the gel-like TCNFs. Both drying methods worked well, but CPD performed better resulting in the specific surface area of 386 m2 g-1 when compared to 172 m2 g-1 and 42 m2 g-1 of freeze dried samples frozen in propane and nitrogen, respectively. HIM imaging of TCNFs was successful but high magnification imaging was challenging because the ion beam tended to degrade the TCNFs. The effect of the imaging parameters on the degradation was studied and an ion dose as low as 0.9 ion per nm2 was required to prevent the damage. This study points out the differences between the gentle drying methods of TCNFs and demonstrates beam damage during imaging like none previously reported with HIM. The results can be utilized in future studies of cellulose or other biological materials as there is a growing interest for both the HIM technique and bio-based materials.

Causation in evidence-based medicine: in reply to Kerry et al.

Kerry et al. criticize our discussion of causal knowledge in evidence-based medicine (EBM) and our assessment of the relevance of their dispositionalist ontology for EBM. Three issues need to be addressed in response: (1) problems concerning transfer of causal knowledge across heterogeneous contexts; (2) how predictions about the effects of individual treatments based on population-level evidence from RCTs are fallible; and (3) the relevance of ontological theories like dispositionalism for EBM.

Causal knowledge in evidence-based medicine. In reply to Kerry et al.'s causation and evidence-based practice: an ontological review.

In Causation and evidence-based practice: an ontological review, Kerry et al. argue that evidence-based practice (EBP) should revise its understanding of causation, and take on board a dispositionalist ontology. We point out that the challenges from complexity discussed by Kerry et al., are not properly addressed by their proposed ontology. Rather, the difference making views of causation Kerry et al. criticize, spell out the relevant aspects of causation, and have a range of advantages compared to dispositionalist accounts. We explore some of these here, with a special focus on the role of causal assumptions in inferences from scientific evidence to clinical decisions. A philosophical account should help us explicate the assumptions that go into causal inference in EBM. In doing so, it enables an understanding of the various ways in which these assumptions might fail, and of how they can be justified.

Safety and tolerability of combination acyclovir 5% and hydrocortisone 1% cream in adolescents with recurrent herpes simplex labialis.

A Phase 3, open-label, multicenter study was conducted to assess the safety of the combination of 5% acyclovir and 1% hydrocortisone cream (AHC cream) in the treatment of recurrent herpes simplex labialis (HSL) in immunocompetent adolescents. Eligible subjects were aged 12 to 17 years and had a history of recurrent labial herpes with two or more episodes during the last 12 months. Subjects initiated treatment at the first signs or symptoms of a herpes recurrence-at the earliest prodromal phase and preferably before the presence of papules or vesicles. Subjects applied the cream topically five times per day for 5 days. Adverse events, categorization of recurrence (ulcerative or nonulcerative), and maximum lesion area (maximum area of an ulcerative lesion) were assessed. Of the 134 subjects analyzed for safety, 131 had data for categorization of recurrence at the post-treatment visit 3 ± 1 weeks after the last dose. Seventy-eight subjects (59.5%) had nonulcerative recurrences, and 53 (40.5%) had ulcerative recurrences. All 131 subjects reached the stage of normal skin, with no signs or symptoms, at the follow-up visit. The mean maximum lesion area in the 53 subjects with ulcerative herpes lesion was 39 mm(2). Five subjects reported five adverse events (secondary herpes labialis recurrences, n = 2; infectious rhinitis, n = 1; application site inflammation, n = 1; bronchial asthma, n = 1). All adverse events were of mild to moderate intensity. The results of this study demonstrate that the combination of AHC cream is well tolerated in the treatment of recurrent HSL in adolescents.

Type-specific detection of high-risk human papillomavirus (HPV) in self-sampled cervicovaginal cells applied to FTA elute cartridge.

BACKGROUND: Most procedures for self-sampling of cervical cells are based on liquid-based media for transportation and storage. An alternative is to use a solid support, such as dry filter paper media. OBJECTIVES: To evaluate if self-sampling of cervicovaginal fluid using a cytobrush (Viba-brush; Rovers Medical Devices B.V., Oss, The Netherlands) and a solid support such as the Whatman Indicating FTA Elute cartridge (GE Healthcare, United Kingdom) can be used for reliable typing of human papillomavirus (HPV), as compared to cervical samples obtained by a physician using a cytobrush and the indicating FTA Elute Micro card and biopsy analysis. STUDY DESIGN: A total of 50 women with a previous high-risk (HR) HPV positive test were invited to perform self-sampling using the Viba-brush and the FTA cartridge and thereafter a physician obtained a cervical sample using the cytobrush and a FTA card, together with a cervical biopsy for histology and HPV typing. Detection of HR-HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59 was performed using three multiplex real-time polymerase chain reaction (PCR) assays. RESULT: All samples contained sufficient amounts of genomic DNA and the self-samples yielded on average 3.5 times more DNA than those obtained by the physician. All women that were positive for HR-HPV in the biopsy sample also typed positive both by self-sampling and physician-obtained sampling. For women with a histological diagnosis of cervical intraepithelial neoplasia grades 2-3 (CIN 2-3) all three HPV samples showed 100% concordance. A higher number of women were HPV positive by self-sampling than by physician-obtained sampling or by biopsy analysis. CONCLUSION: The Viba-brush and the FTA cartridge are suitable for self-sampling of vaginal cells and subsequent HR-HPV typing.

Novel administration technique for large-particle stabilized hyaluronic acid-based gel of nonanimal origin in facial tissue augmentation.

The use of large-particle stabilized hyaluronic acid-based gel of nonanimal origin (NASHA™) for facial aesthetic procedures is widespread and increasing. A panel of experts with extensive clinical experience with NASHA based gel recently attended an advisory board meeting to develop guidelines for its use in volumetric tissue augmentation.Discussions included details of the blunt-cannula injection technique currently recommended for administration of large-particle NASHA-based gel. With the aim of optimizing patient comfort and control over administration of NASHA-based gel, the panel members explored an alternative,sharp-needle technique. In this article we describe the new technique in detail, together with practical recommendations and precautions. The technique has several advantages over blunt-cannula injection: improved patient comfort, lack of need for a skin incision, increased precision regarding the implant position, and improved control of injection volume. However, the sharp-needle technique requires a high level of skill and a good knowledge of facial anatomy.

Use of FTA card for dry collection, transportation and storage of cervical cell specimen to detect high-risk HPV.

BACKGROUND: The FTA elute micro card, which enable the collection, transport, and archiving of DNA could be an attractive alternative to a liquid based collection system for detection of human papillomavirus (HPV). OBJECTIVES: To develop a method based on the FTA elute micro card for dry collection of cervical epithelial cell samples, suitable for subsequent PCR-based HPV testing. STUDY DESIGN: The method was evaluated by a comparison of the DNA collected by cytobrush and the regular FTA elute micro card from 50 cervical cell samples. The method was then used to estimate the DNA amount in 1040 samples applied to the indicating FTA elute micro card. RESULT: The agreement in HPV positivity between the cytobrush and FTA samples (94%) was excellent (kappa=0.88, 95% CI 0.748-1). All the 1040 samples on the indicating FTA card had sufficient amounts of genomic DNA (>10 copies of a single copy gene) to be suitable for HPV typing. In 53 of the 1040 women the day in the menstrual cycle was noted, and the copy number during follicular phase day 9-13 was found to be statistically significantly lower than for the other three stages in the menstrual cycle (day 4-8, 14, >14) and during menopause. CONCLUSION: The indicating FTA elute micro card represents a suitable medium for collection of cervical cell samples, although follow-up studies are needed to verify the detection of low frequency HPV types.

Efficacy of HPV DNA testing with cytology triage and/or repeat HPV DNA testing in primary cervical cancer screening.

BACKGROUND: Primary cervical screening with both human papillomavirus (HPV) DNA testing and cytological examination of cervical cells with a Pap test (cytology) has been evaluated in randomized clinical trials. Because the vast majority of women with positive cytology are also HPV DNA positive, screening strategies that use HPV DNA testing as the primary screening test may be more effective. METHODS: We used the database from the intervention arm (n = 6,257 women) of a population-based randomized trial of double screening with cytology and HPV DNA testing to evaluate the efficacy of 11 possible cervical screening strategies that are based on HPV DNA testing alone, cytology alone, and HPV DNA testing combined with cytology among women aged 32-38 years. The main outcome measures were sensitivity for detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) within 6 months of enrollment or at colposcopy for women with a persistent type-specific HPV infection and the number of screening tests and positive predictive value (PPV) for each screening strategy. All statistical tests were two-sided. RESULTS: Compared with screening by cytology alone, double testing with cytology and for type-specific HPV persistence resulted in a 35% (95% confidence interval [CI] = 15% to 60%) increase in sensitivity to detect CIN3+, without a statistically significant reduction in the PPV (relative PPV = 0.76, 95% CI = 0.52 to 1.10), but with more than twice as many screening tests needed. Several strategies that incorporated screening for high-risk HPV subtypes were explored, but they resulted in reduced PPV compared with cytology. Compared with cytology, primary screening with HPV DNA testing followed by cytological triage and repeat HPV DNA testing of HPV DNA-positive women with normal cytology increased the CIN3+ sensitivity by 30% (95% CI = 9% to 54%), maintained a high PPV (relative PPV = 0.87, 95% CI = 0.60 to 1.26), and resulted in a mere 12% increase in the number of screening tests (from 6,257 to 7,019 tests). CONCLUSIONS: Primary HPV DNA-based screening with cytology triage and repeat HPV DNA testing of cytology-negative women appears to be the most feasible cervical screening strategy.

Human papillomavirus and Papanicolaou tests to screen for cervical cancer.

BACKGROUND: Screening for cervical cancer based on testing for human papillomavirus (HPV) increases the sensitivity of detection of high-grade (grade 2 or 3) cervical intraepithelial neoplasia, but whether this gain represents overdiagnosis or protection against future high-grade cervical epithelial neoplasia or cervical cancer is unknown. METHODS: In a population-based screening program in Sweden, 12,527 women 32 to 38 years of age were randomly assigned at a 1:1 ratio to have an HPV test plus a Papanicolaou (Pap) test (intervention group) or a Pap test alone (control group). Women with a positive HPV test and a normal Pap test result were offered a second HPV test at least 1 year later, and those who were found to be persistently infected with the same high-risk type of HPV were then offered colposcopy with cervical biopsy. A similar number of double-blinded Pap smears and colposcopies with biopsy were performed in randomly selected women in the control group. Comprehensive registry data were used to follow the women for a mean of 4.1 years. The relative rates of grade 2 or 3 cervical intraepithelial neoplasia or cancer detected at enrollment and at subsequent screening examinations were calculated. RESULTS: At enrollment, the proportion of women in the intervention group who were found to have lesions of grade 2 or 3 cervical intraepithelial neoplasia or cancer was 51% greater (95% confidence interval [CI], 13 to 102) than the proportion of women in the control group who were found to have such lesions. At subsequent screening examinations, the proportion of women in the intervention group who were found to have grade 2 or 3 lesions or cancer was 42% less (95% CI, 4 to 64) and the proportion with grade 3 lesions or cancer was 47% less (95% CI, 2 to 71) than the proportions of control women who were found to have such lesions. Women with persistent HPV infection remained at high risk for grade 2 or 3 lesions or cancer after referral for colposcopy. CONCLUSIONS: The addition of an HPV test to the Pap test to screen women in their mid-30s for cervical cancer reduces the incidence of grade 2 or 3 cervical intraepithelial neoplasia or cancer detected by subsequent screening examinations. (ClinicalTrials.gov number, NCT00479375 [ClinicalTrials.gov].).

Restylane SubQ, a non-animal stabilized hyaluronic acid gel for soft tissue augmentation of the mid- and lower face.

For people requiring large volumes to shape facial contours, add volume to a sunken midface, or correct asymmetry, the options today are limited. Fat injections for adding volume, solid implants for cheeks and chin enhancement, face lift and injectable permanent or semi-permanent products are some of the alternatives used. With the trend towards less invasive and nonpermanent alternatives to plastic surgery, the use of injectable filler materials for facial rejuvenation and correction of soft-tissue defects is becoming increasingly popular. These materials provide volume expansion within the dermis, thereby smoothing out overlying facial wrinkles and enhancing facial contours. Ease of application, minimal procedural discomfort, and rapid patient recovery make injectable fillers well suited for outpatient use. Ideally, a filler material should be biocompatible, nontoxic, nonimmunogenic, and nonmigratory. Several biomaterials have been developed, such as bovine collagen, autologous and allogeneic human collagen, autologous fat, fibroblasts, and hyaluronic acid. However, although they are largely biocompatible, reabsorption and lack of sustained cosmetic effect are major drawbacks. Non-animal stabilized hyaluronic acid (NASHA) offers a longer-lasting aesthetic effect than bovine collagen or avian hyaluronic acid in facial soft-tissue augmentation, and a potentially lower risk of inflammatory reactions. Restylane SubQ is a new NASHA product indicated for deep subcutaneous or supraperiostal injection to replace volume loss in facial adipose tissues and create more defined facial contours.

HIV-related lipodystrophy and facial lipoatrophy: the role of Restylane SubQ in reversing facial wasting.

HIV-associated lipodystrophy syndrome affects approximately 50% of HIV-positive patients, particularly those receiving antiretroviral therapy based on nucleoside reverse transcriptase inhibitors and protease inhibitors. Growing evidence suggests that certain antiretroviral drugs may precipitate or exacerbate lipoatrophy and associated metabolic abnormalities, and this is an important consideration when selecting appropriate treatment regimens. However, because of problems of cross-resistance among antiretroviral drug classes and other treatment-related toxicities, it is likely that, at some stage, the HIV-infected patient will have to take drugs that confer a risk of development of lipodystrophy syndrome. Combination therapy for HIV, known as highly active antiretroviral therapy (HAART), has dramatically altered the prognosis for the HIV-infected individual. With optimal use of HAART, which includes regular monitoring of viral load, viral resistance, and compliance with medication, HIV infection has changed from being a fatal disease to a lifelong infection. However, HAART-related lipodystrophy syndrome, and especially facial lipoatrophy, is of great concern for patients and physicians involved in HIV care. For the patient, facial lipoatrophy is a major stigma that affects self-esteem and social interaction, and in some cases, it is a cause of noncompliance with HAART. Accordingly, many treatment-experienced HIV patients are requesting, and being treated with, various dermal fillers for cosmetic correction of facial lipoatrophy. Prior to the introduction of HAART, when life expectancy for the HIV-infected individual was severely limited, permanent fillers were widely used for this purpose. Because these products remain in situ indefinitely and the facial soft tissues change over time, the permanent fillers are no longer a satisfactory treatment option. Now that HIV infection has been transformed into a chronic but not necessarily life-threatening disease, there is an urgent need for a safe, biodegradable, and biocompatible alternative dermal filler for treating HIV-associated facial lipoatrophy.

Colposcopic and histopathologic evaluation of women participating in population-based screening for human papillomavirus deoxyribonucleic acid persistence.

OBJECTIVE: Evaluation of colposcopic and histopathological findings in women screened for cervical human papillomavirus deoxyribonucleic acid persistence. STUDY DESIGN: A total of 12 527 women, aged 32 to 38 years old, attending the population-based cervical cancer screening program in Sweden were randomized 1:1 to mock testing or human papillomavirus deoxyribonucleic acid testing by general primer 5+/6+ polymerase chain reaction and subsequent typing. Human papillomavirus deoxyribonucleic acid-positive women with a normal Papanicolaou smear (n=341) and an equal number from the control group were human papillomavirus tested on average 19 months later. One hundred nineteen women with type-specific human papillomavirus persistence and 111 controls were referred to colposcopy, and 84.8% attended. RESULTS: Histopathology from colposcopically directed biopsies confirmed cervical intraepithelial neoplasia grade 2 or 3 in 28 of 100 of the women with human papillomavirus deoxyribonucleic acid persistence and in 2 of 95 among controls. CONCLUSION: Among women with normal Papanicolaou smear attending population-based screening, the positive predictive value of human papillomavirus deoxyribonucleic acid persistence for detection of biopsy-confirmed cervical intraepithelial neoplasia 2 or 3 was 29%.

Reduced loss of hand bone density with prednisolone in early rheumatoid arthritis: results from a randomized placebo-controlled trial.

BACKGROUND: Bone damage in rheumatoid arthritis presents as osteoporosis and joint erosions. Prednisolone has been shown to reduce the rate of hand joint destruction as seen on radiography but has not been shown to reduce the rate of hand bone loss. METHODS: In a double-blind study comparing oral prednisolone (7.5 mg/d for 2 years) with placebo, hand bone density assessed with digital x-ray radiogrammetry was examined in 95 patients with rheumatoid arthritis with disease duration of less than 2 years. RESULTS: The mean loss of hand bone density was less in prednisolone-treated patients compared with placebo-treated patients at the 1-year follow-up (-0.011 vs -0.022 g/cm(2)) (P = .005) and at the 2-year follow-up (-0.026 vs -0.039 g/cm(2)) (P = .03). The mean percentage group difference in loss of hand bone density was 2.8% (P = .004) at the 1-year follow-up and 3.5% (P = .01) at the 2-year follow-up. In the first year, C-reactive protein, a marker of inflammation, was strongly correlated with hand bone loss in placebo-treated patients but not in prednisolone-treated patients, suggesting that prednisolone breaks the link between bone loss and inflammation. CONCLUSIONS: To our knowledge, this is the first double-blind randomized study to show that disease-related loss of hand bone density in rheumatoid arthritis can be decelerated by prednisolone. This finding suggests that the deleterious effect of prednisolone on bone may be counteracted by its anti-inflammatory effect.

Chlamydia trachomatis infection and persistence of human papillomavirus.

Human papillomavirus (HPV) persistence is the major cause of cervical cancer, but most HPV infections will not persist and risk factors for HPV persistence are not well known. Chlamydia (C.) trachomatis infection seems to also be associated with cervical cancer. We investigated whether C. trachomatis infection is a risk factor for HPV persistence. In a cohort of 12,527 women participating in a population-based HPV screening trial in Sweden, 6,418 women completed testing for HPV DNA by general primer PCR and typing by reverse dot blot hybridization. On average 19 months later, 303 women that had been HPV-positive and had normal cytology at enrollment completed a new HPV test. Environmental exposures were assessed by an 87-item questionnaire. Previous sexually transmitted infections were also investigated by serology. At follow-up, 44% of the women were positive for the same type of HPV DNA as at enrollment. Persistence correlated with length of follow-up (p < 0.01) and condom use seemed to protect against HPV persistence (p < 0.05). The most significant risk factor for persistent presence of HPV DNA was self-reported history of previous C. trachomatis infection (relative risk in multivariate model = 2.09; 95% confidence interval = 1.05-4.18). We conclude that persistence of oncogenic HPV infections is more likely among women with a previous C. trachomatis infection.

Duplex real-time polymerase chain reaction assay for detection and quantification of herpes simplex virus type 1 and herpes simplex virus type 2 in genital and cutaneous lesions.

BACKGROUND: A sensitive and specific method for detecting herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) is important for diagnosing genital and cutaneous infections. GOAL: The goal of this study was to compare quantitative real-time polymerase chain reaction (qPCR) with virus culture for diagnosis of genital and cutaneous HSV-1 and HSV-2. STUDY DESIGN: A duplex qPCR system for quantification of DNA from HSV-1 and HSV-2 was developed. Duplicate swabs for PCR and virus culture were collected from 89 patients attending our sexually transmitted infection and dermatology clinic. RESULTS: The duplex qPCR had a linear measure interval of 10-10 copies/mL. The detection limit was between 1 and 5 copies per reaction. qPCR detected HSV in 57 (64%) specimens and virus was isolated in 45 (50%) cases. First-episode infections showed higher viral quantities with a median value of 4.2 x 10 copies per reaction compared with recurrent infections with 1.0 x 10 (P = 0.0002). HSV-1 was more likely to be the cause of first-episode genital infections (72%), and HSV-2 of recurrent and atypical genital manifestations (73%). CONCLUSION: Real-time PCR is a sensitive method for diagnosing genital herpes, and the duplex format is convenient for typing. The method increased the detection rate by 27% compared with virus culture.

Cytologic screening and human papilloma virus test in women undergoing artificial fertilization.

BACKGROUND: Infertile women in Sweden are offered in vitro fertilization (IVF) within the frame of the social security system. The present investigation was undertaken to evaluate the prevalence of genital human papilloma virus (HPV) infection in relation to the results of cytologic screening and to the infertility in these women. MATERIAL AND METHODS: Two hundred and fourteen women, mean age 32 years (range 20-40), admitted to the Center for Reproduction at Uppsala University Hospital for investigation of infertility and IVF were studied. Human papilloma virus tests were performed by a sensitive polymerase chain reaction-based technique in cervical smears obtained at a medical examination or during oocyte retrieval. Cytologic screening results were obtained from medical records or at the time of investigation. The infertile women were compared with 197 healthy female controls. RESULTS: Infertility resulted from female factors in 47% and male factors in 29% of the cases, and remained unexplained in 24%. Seven percent of the infertile women were HPV-positive compared with 9.1% of the controls. Only genital and oncogenic HPV types were identified. Human papilloma virus type 16 was most prevalent, and examination of the HPV 16 E6 gene showed that this prototype predominated over variants. No correlation was found between HPV infection and cause of infertility. Abnormal cytology was observed in 2.3% of the infertile women and 4.1% of the controls. CONCLUSIONS: Human papilloma virus infections might appear somewhat less frequently in infertile women admitted for IVF than in a control population. In both groups HPV infection was more common than cytologic abnormalities, possibly indicating that present HPV tests are more sensitive in detecting HPV infections than cytologic screening.

Population-based type-specific prevalence of high-risk human papillomavirus infection in middle-aged Swedish women.

Human papillomavirus (HPV) DNA testing can be used to identify women at risk of the development of cervical cancer. The cost-effectiveness of HPV screening is dependent on the type-specific HPV prevalence in the general population. The present study describes the prevalence and spectrum of high-risk HPV types found in a large real-life population-based HPV screening trial undertaken entirely within the cervical screening program offered to middle-aged Swedish women. Cervical brush samples from 6,123 women aged 32-38 years were analyzed using a general HPV primer (GP5+/6+) polymerase chain reaction-enzyme immunoassay (PCR-EIA) combined with reverse dot-blot hybridization for confirmation and HPV typing by a single assay. In this study, 6.8% (95% CI 6.2-7.5) (417/6,123) were confirmed as high-risk HPV positive. Infections with 13 different high-risk HPV types were detected, of which HPV 16 was the most prevalent type (2.1%; 128/6,123), followed by HPV 31 (1.1%; 67/6,123). Any one of the HPV types 18, 33, 35, 39, 45, 51, 52, 56, 58, 59, or 66 was detected in 3.6% (223/6,123) of the women. Infection with two, three, and five types simultaneously was identified in 32, 5, and 1 women, respectively. The combination of PCR-EIA as a screening test and reverse dot-blot hybridization as a confirmatory test, was found to be readily applicable to a real-life population-based cervical screening. The type-specific HPV prevalence found support in previous modeling studies suggesting that HPV screening may be a favorable cervical screening strategy.