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1.
The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively.  相似文献   
2.
This study examined the influence of metamemory (i.e., self-report of memory ability and skills), in combination with other factors, on quality of life for people with multiple sclerosis (MS). Participants (482 persons with MS) completed instruments to measure functional limitations, depressive symptoms, metamemory, and perceived quality of life. Participants reported greater satisfaction with their memory performance but less frequent use of memory aids and strategies compared with 115 older adults on whom the instrument was originally tested. Components of metamemory were significantly related to neurological disability, duration of disease, depressive symptoms, age, and quality of life. Depressive symptoms had a higher impact than other variables in the final regression model on quality-of-life prediction.  相似文献   
3.
The implantation of ventriculo-peritoneal (VP) shunting systems is the most commonly performed neurological procedure in children with hydrocephalus. Although the overall complication risk is low, the cumulative risk of shunt failure is high and unfortunately results in a high prevalence of revision surgeries. In this study, we explored the concept that some pediatric patients may develop an immune response to either the proteins attached to the silicone implant surface or to the biomaterial itself, and that this reaction may contribute to VP shunt failure in some individuals. The data displays that the sterile shunt malfunction group had a higher rate of protein deposition and increased levels of autoantibodies to the extracted surface proteins as compared to individuals with functioning shunting systems. The precise nature of the shunt-bound proteins that serve as antigens in this experiment have not yet been determined. The data also indicated that some individuals develop antibodies to polymeric substances that cross-react with partially polymerized acrylamide. The detection of significant amounts of shunt-bound protein, antibody responses to these proteins and to polymeric substances suggest that an immunological response to these proteins may play a role in the mechanism behind sterile shunt malfunctions.  相似文献   
4.
Chromatin assembly and DNA replication are temporally coupled, and DNA replication in the absence of histone synthesis causes inviability. Here we demonstrate that chromatin assembly factor Asf1 also affects DNA replication. In budding yeast cells lacking Asf1, the amounts of several DNA replication proteins, including replication factor C (RFC), proliferating cell nuclear antigen (PCNA), and DNA polymerase epsilon (Pol epsilon), are reduced at stalled replication forks. In contrast, DNA polymerase alpha (Pol alpha) accumulates to higher than normal levels at stalled forks in asf1Delta cells. Using purified, recombinant proteins, we demonstrate that RFC directly binds Asf1 and can recruit Asf1 to DNA molecules in vitro. We conclude that histone chaperone protein Asf1 maintains a subset of replication elongation factors at stalled replication forks and directly interacts with the replication machinery.  相似文献   
5.
Summary In order to study the long-term immunogenicity of interferon-2c (Berofor) in cancer patients, serum was collected starting in 1983 from study patients with various proliferative diseases who received interferon-2c at different doses, according to different schedules, and via different routes. A total of 1992 samples were tested for the presence of anti-interferon-2c antibodies. Due to long-term interferon-2c treatment, 346 patients were eligible for induction of neutralizing anti-interferon antibodies over a treatment period of 252 months. Most patients were treated for longer than 6 months. Of the 346 patients, three patients (0.87%) exhibited measurable titers of neutralizing antibodies following therapy with interferon-2c. One hundred and sixty-three patients suffered from non-Hodgkin lymphomas, leukemias, and preleukemias. One patient with chronic myeloid leukemia experienced antibody induction under therapy. The other 183 patients had solid tumors. Two of them reacted with antibody production. All titers were very low (1:12, 1:8, and 1:64). Compared with figures reported for other interferon- preparations, the propensity of interferon-2c to induce neutralizing antibodies seems to be very low. This property might be related to arginines occurring as critical residues in positions 23 and 34 of the interferon-2c molecule.Abbreviations ANB antiviral neutralization bioassay - CE competitive sandwich ELISA - EBI Ernst Boehringer Institut - IFN interferon  相似文献   
6.
Expression of CD44 splice variants in human skin and epidermal tumours   总被引:4,自引:0,他引:4  
Splice variants of the adhesion molecule CD44 (CD44v) are important in the lymphatic spread of rat carcinoma cells. In several human tumours expression of CD44v correlates with tumour progression. However, little is known about the physiological functions of distinct variant exons. Here we report on the immunohistological evaluation of CD44 expression in normal human skin and epidermal tumours which do not metastasise, or do so vary rarely. Frozen tissues were stained with a panel of monoclonal antibodies, recognizing epitopes of the CD44 standard isoform, as well as of variant exons v5, v6, v7, v7–v8 and v10. Stratum basale and spinosum as well as the root shaft of hairs reacted strongly with the whole panel of anti-CD44 antibodies. Stratum corneum, acinar cells of sebaceous and eccrine sweat glands stained with anti-CD44v5, anti-CD44v6 and anti-CD44v7, but not with anti-CD44v10, the latter recognizing the epithelial isoform (CD44v8–v10) of CD44. Ductal cells of glands and apocrine glands did not express CD44v. Compared with its expression in normal human skin, CD44v expression was reduced in basal cell carcinoma and squamous cell carcinoma of the skin. This was particularly true of CD44v10. The expression of CD44v in normal skin and dermal appendages indicates that not all combinations of variant exons are involved in tumour progression. Since the epithelial isoform is particularly downregulated in basal cell carcinoma and squamous cell carcinoma of the skin, it is unlikely that exons v8–v10 play a role in tumour progression. Rather, they may be of functional importance in maintenance of the epidermal structure.  相似文献   
7.

Since the emergence of the COVID-19 pandemic, there has been an increasing body of research focused on the effects that measures like stay-at-home orders and social distancing are having on other aspects of health, including mental health and sexual health. Currently, there are limited extant data on the effects of the pandemic on sexual and gender minorities. Between April 15, 2020, and May 15, 2020, we invited participants in an ongoing U.S. national cohort study (Together 5000) to complete a cross-sectional online survey about the pandemic, and its effects on mental and sexual health and well-being (n?=?3991). Nearly all (97.7%) were living in an area where they were told they should only leave their homes for essentials. Most (70.1%) reported reducing their number of sex partners as a result of the pandemic. Among the 789 participants prescribed HIV pre-exposure prophylaxis (PrEP), 29.9% said they stopped taking their PrEP entirely, and 14.2% started selectively skipping doses. For those who had been taking PrEP, discontinuing PrEP was associated with having no new sex partners (β?=?0.90, 95% CI 0.40–1.40). Among the 152 HIV-positive participants, 30.9% said they were unable to maintain an HIV-related medical appointment because of the pandemic and 13.8% said they had been unable to retrieve HIV medications. Additionally, 35.3% of participants were experiencing moderate to severe anxiety because of the pandemic and 36.7% reported symptoms of depression. In a multivariable logistic regression, reporting a new sex partner in the prior 30 days was significantly associated with being aged 30 or older (vs. not, AOR?=?1.21), being Black (AOR?=?1.79) or Latinx (AOR?=?1.40, vs. white), and being unsure if they had been in close contact with someone diagnosed with COVID-19 (AOR?=?1.32, vs. no contact). It was unassociated with COVID-19-induced anxiety, depression, or knowing someone hospitalized with COVID-19. The pandemic has caused disruptions in sexual behavior (partner reduction) as well as difficulties navigating PrEP and HIV care continua. Findings will guide more comprehensive public health responses to optimize HIV prevention and treatment in the era of COVID-19.

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8.
BACKGROUND: Although cataract surgery is highly developed today, there are still problems such as secondary cataract. In polishing the posterior capsule lens, epithelial cells often remain, causing secondary cataracts. Additionally, there are the problems of tissue heating and endothelial cell loss during phacoemulsification by ultrasound. This could be another field for improvement of cataract surgery by using the waterjet. METHODS: After removing the cornea of freshly enucleated porcine bulbs, we used the water jet from 4 to 12 bar. The hit angel on the capsule varied between 45 degrees and 90 degrees. RESULTS: Rupture of the posterior capsule occurred at a mean of 8.5 bar using the jet at 45 degrees and a mean of 8.6 bar using the jet at 90 degrees. CONCLUSION: The waterjet pressure should not be over 4 bar during polishing of the posterior capsule.  相似文献   
9.
Zusammenfassung Anhand der anamnestischen Daten von 50 Patienten mit chronischer posttraumatischer Osteomyelitis wird eine Punktebewertung zur Beurteilung des Schweregrades der Erkrankung entwickelt, die neben der Gesamtdauer der Erkrankung den prozentualen Anteil der stationären Behandlung sowie die Anzahl der chirurgischen Eingriffe berücksichtigt. Zur Objektivierung des klinischen Verlaufes wird eine zweite Skala (München-Murnau-Skala) vorgestellt, welche die äußeren Wundverhältnisse, die röntgenologischen Befunde sowie die Blutkörperchensenkungsgeschwindigkeit erfaßt. Anhand einer Autovaccinetherapie bei 18 Patienten wird die Objektivierung des Therapieerfolges mit Hilfe dieser Skala gezeigt.
Scoring system for evaluation of severity and progress of chronic posttraumatic osteomyelitis
Summary From the anamnestic data of 50 patients suffering from chronic posttraumatic osteomyelitis a severity scoring system was developed, based on the duration of the disease, the time of hospitalization and the number of surgical interventions. The clinical course of 18 patients, undergoing an auto-vaccination treatment, was registered by another scoring system (Munich-Murnau-Scale) regarding wound morphology, bone radiology and erythrocyte sedimentation rate.
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10.
PURPOSE: As the number of pediatric cancer survivors increases, so does the number of survivors previously exposed to anthracyclines as part of their cancer therapy. Because screening is costly, some have suggested that health-related quality of life (HRQL) measures might be useful in focusing screening tests on those patients with cases most likely to display positive findings. This study reports on the predictive ability of HRQL measures to detect patients with abnormalities on serial cardiac testing. METHODS: Using 127 patients from the ACE-Inhibitor after Anthracycline (AAA) Trial, this study compared serial measures of the Short Form-36 (SF-36; for ages > 13 years) and Child Health Questionnaire-Child Form 87 (CHQ-CF87; for ages < or = 13 years) to serial cardiac performance tests including echocardiographic shortening fraction, left ventricular end systolic wall stress (LVESWS), LVESWS-index, and maximal cardiac index (MCI; a measure of cardiac output at peak exercise). RESULTS: Generally, there was no clinically or statistically significant correlation between any HRQL measure and any cardiac function measure except between MCI and vitality and physical functioning. For each of these measures, the correlation between MCI was statistically significant (P < .006), but each HRQL subscale could explain no more than 7% of the variation in MCI. HRQL measures were not predictive of any other cardiac function measure. CONCLUSION: HRQL measures should not be used in isolation as a screen for cardiac function abnormalities in patients exposed to anthracylines who already have a mild degree of ventricular dysfunction. Patient history appears to be no substitute for cardiac testing in this cohort.  相似文献   
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