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Polymeric PPDs that reduce the pour point of crude oil are one of the most important chemicals utilized in the petroleum industry, especially when transporting waxy oil. The regulation of the structure of such polymers with different hydrophobic-hydrophilic balance makes it possible to select an effective PPD to improve the low-temperature properties of crude oil. On this basis, the current work presents a series of syntheses of copolymers based on α-olefins and maleic anhydride and their modification by the amidation reaction with primary amines: butylamine, hexylamine, hexadecylamine, octadecylamine, and benzylamine. The structure of the copolymers was determined through FTIR spectroscopy and 1H and 13C NMR spectroscopy. The molecular weight of the copolymers was identified by the method of light scattering. The study of the effect of modified copolymers on rheological behavior and lowering the pour point was performed for waxy crude oil from the Akshabulak field (Kazakhstan). Rheological tests have shown that the synthesized copolymers improve the fluidity of oil and reduce the values ​of the yield stress of oil. Optical micrograph showed that the modified copolymers form fine crystals of paraffins and exhibit dispersing properties. [ABSTRACT FROM AUTHOR]

Peripartum depression (PPD) is a common mental health complication of pregnancy and increases risk for maternal mortality and poorer outcomes for children. Despite its importance, screening rates vary across organizations and care team members. The goal of the current study was to explore the perspectives from care team members in both behavioral health and acute care settings about how they screen and refer pregnant and post pregnant women for PPD, what training around PPD is currently offered by their organization, and if they could benefit from additional PPD training. Data were collected from an online self-report survey of care team members from behavioral health and acute care settings in the US. Questions focused on (1) when/if the care teams had a screening protocol for PPD, (2) beliefs about the efficacy of their organization's PPD screening, identification, and referral process, and (3) if their organization currently offered or needed training around the topic of PPD. A total of 794 care team members in behavioral health and acute care responded to the survey between December 2021 and May 2022. Nearly, all (96.7%) reported having a specific protocol for screening for PPD when they know a patient is pregnant; however, only 69.6% of respondents routinely screen regardless of symptoms being reported by the patient. While 93.3% of the sample believed their organization does a good job screening for and identifying PPD, gaps in the referral processes were described, especially in acute settings. 95.3% of the sample reported their organization currently gives training in screening, identifying, or treating PPD or in the process for establishing outpatient referrals for PPD care for care team members who have direct contact with pregnant patients; however, 96.5% also reported their organization would benefit from additional training in one or more of these areas. High rates of self-reported PPD screening and training indicate that care team members in both behavioral health and acute care are aware of the importance of maternal mental health issues. However, other research indicates that high rates of screening may not lead to improved outcomes, and there are still high rates of maternal suicide and suicidal ideation in the US. It is possible that high self-reported screening rates may indicate a false sense of security such that care team members feel the issue is addressed while problems remain. Alternatively, many respondents felt their organizations would benefit from further training, perhaps indicating an awareness of this gap. Care team members in behavioral health and acute care settings should increase collaboration to ensure high rates of screening lead to improved maternal mental health care. [ABSTRACT FROM AUTHOR]

Para-Phenylenediamine (PPD) is a commonly used dye intermediate in permanent hair dye formulations, and exposure to PPD has been associated with allergic contact dermatitis at certain doses. Determine the concentration of PPD in a survey of self-application permanent hair dye products, and perform a quantitative risk assessment to determine the risk of skin sensitization induction following application of these products. Consumer exposure levels (CELs) to PPD following application of hair dye products were estimated using the maximum amount of hair dye that can adhere to the surface area of the scalp, the measured concentration of PPD in the hair dye product, a retention factor, the dermal absorption of PPD, and the surface area of the scalp. CELs were calculated for various exposure scenarios, and were stratified by hair dye shade. All estimated CELs did not exceed the acceptable exposure level. Specifically, margins of safety ranged from 2.3 to 1534 for black dyes, 2.9 to 5031 for brown dyes, and 26 to 5031 for blonde dyes. Findings suggest that use of the evaluated permanent hair dyes, under the evaluated exposure scenarios, would not be expected to induce skin sensitization due to PPD exposure at concentrations ≤0.67%. [ABSTRACT FROM AUTHOR]

Yield components of dryland maize (Zea mays L.) planted in a double skip-row versus solid pattern were compared at three plant densities in four trials. Ear and kernel characteristics were determined. No row-pattern by-population interaction occurred. Increased yield was because of increased kernel weight, size, and number, whereas decreased yield from skipping rows was due to shorter ears. Increasing plant density reduced ear length and kernel number. Double skip-row planting increased yield by promoting kernel size and weight in semi-arid environments. Skipping two rows and increasing plant density affected yield components that should be considered in making planting decisions. [ABSTRACT FROM AUTHOR]

The selectivity of glutamate microdisc biosensors coated with poly(o-phenylenediamine) (PPD) as the interference-rejecting layer against ascorbic acid was observed to be very low. Enhancement in the selectivity was noticed when the electropolymerization potential for the polymerization of the o-phenylenediamine monomer was decreased from 0.65 V to 0.40 V vs. Ag/AgCl. The selectivity coefficient increased from -34.93±3.75% (n = 5) to 53.05 ± 4.33% (n = 3). Decreasing the polymerization potential decreases the rate of formation of the polymer and improves the compactness of the polymer layer formed, thereby increasing the selectivity of the electrodes. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are the most powerful antigen presenting cells, capable of inducing T-dependent immune responses even in naive T cells. DCs are of special interest as cellular adjuvants for immunity induction in clinical settings and several methods for their generation and maturation are recently under investigation. The present study was set out to define the effects of PPD (Purified Protein Derivative), a mycobacterial extract used in the tuberculin skin test, on in vitro differentiation and maturation of human monocyte derived dendritic cells. Immature DCs were prepared from the peripheral blood monocytes of healthy volunteers by culturing in a medium supplemented with granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). The resultant cells were then stimulated with PPD extract and their properties such as cell morphology and the expression of key surface molecules were compared with tumor necrosis factor-α (TNF-α) stimulated immature DCs. Our results suggest that mycobacterial purified extract is as potent as TNF-α, a well-established DC stimulator, in induction of maturation in human monocyte derived DCs. We also ruled out the contribution of lipopolysaccharide (LPS) and beta-glucan contamination in maturation effect of PPD preparations. So, PPD as an examined safe material for in vivo consumption could be used to stimulate DC maturation in DC based immunotherapy protocols. [ABSTRACT FROM AUTHOR]

The QuantiFERON-TB Gold (QFT-G) is a new FDA approved test for diagnosing Mycobacterium tuberculosis infection. This test detects the release of interferon-gamma (IFNγ) in whole blood from sensitized persons when it is incubated with mixtures of synthetic peptides representing 2 proteins present in M. tuberculosis: early secretory antigenic target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10). These antigens have greater specificity than tests using purified protein derivative (PPD) as the tuberculosis antigen. The CDC recommends that QFT-G may be used in all circumstances in which the TB skin test is currently used, including contact investigations, evaluation of recent immigrants, and sequential-testing surveillance programs for infection control (e.g., those for health-care workers). Advantages of the QFT-G include: no false-positive reactions from previous BCG vaccination; no cross-reactivity with non-tuberculous mycobacterium infections; and, better detection of active tuberculosis. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) continues to be a leading infectious cause of death worldwide, and it remains a serious public health problem in developing countries. To determine the prevalence of tuberculosis infection among garment workers, the authors conducted a retrospective prevalence survey of employees working in garment factories in Qatar from January 2000 to June 2003. A mass screening of garment factory workers was carried out by chest X-ray and Mantoux skin test at the Rumailah Hospital, Hamad Medical Corporation. The authors considered those workers with a purified protein derivative (tuberculin) reaction of &nvge; 15 mm to be infected with TB, or to have a latent TB infection. Workers with active TB diseases were confirmed by histopathological and mycobacteriological examinations. The authors studied a total of 2,774 garment factory workers, and they found 43% of them to be infected (reaction &nvge; 15 mm). The mean age of the infected subjects was significantly higher than that of the noninfected subjects (p < .001); 53% of the infected subjects were between 30 and 40 years of age. Indians and Pakistanis made up the most frequent nationalities among the infected subjects (50.0%), followed by Nepalis (44.1%). The prevalence rate of tuberculosis infection in garment workers was high. Overcrowding in factories and residential facilities increases the risk of TB transmission. [ABSTRACT FROM AUTHOR]

Patients with chronic renal failure are at increased risk for tuberculosis (TB). Centers for Disease Control and Prevention (CDC) have recommended annual skin testing for TB, with tuberculin-purified protein derivative (PPD), in patients with chronic renal failure. Uremia alters the macrophage function, which can lead to anergy for skin tests. The aim of this prospective study was to determine the prevalence of positive tuberculin skin test (TST) and the booster effect of TST in hemodialysis patients living in a relatively underdeveloped portion of the country. Material and Methods. Patients were recruited from Van (Yuzuncu Yil University Hospital, Yuksek Ihtisas Hospital) and the Mus State Hospital). At the time of this study, a total of 143 patients were under hemodialysis treatment in these hemodialysis centers, and among them, 124 were included in the study. Informed consent was obtained before inclusion in the study. A positive PPD was an induration of >10 mm in response to five tuberculin units of PPD (RT23-Tween 80), at 72 h. TST-negative patients received a booster TST 10 days later, ~ 10 cm away from the previous intracutaneous injection. The test dose could not be increased due to unavailability of this kind of preparation. The test was performed and interpreted in the same way. Skin testing was performed in June and December 2003. Patients with known active TB are not included in the study. Testing was not done in hospitalized patients to rule out effects of other disease states. Results. Mean age of the patients was 45.3 ± 16 (range 13–82) years. All patients were on HD treatment twice ( n : 14) or three times ( n : 110) weekly. Duration of dialysis before TST was 30 ± 17 (12–84) months. With the first test ( n : 14), 11.3% of the patients showed a positive reaction; the second test added ( n : 15) 12.1% more TST-positive patients, reaching a total of ( n : 29) 23.4% of the patients with a positive TST. The mean induration of the positive TST was 16 ± 4 mm in the first test and 15 ± 3 mm in the second. Five (17.2%) of the patients with positive PPD and two of the patients (2.1%) with negative PPD results subsequently developed active TB within 12 months. Conclusion. We found a significant booster effect in our hemodialysis patients using TST-2. Repeat PPD test with the same dosage could detect positive patients more than twofold higher. Among positive PPD patients, TB incidence is considerably high. [ABSTRACT FROM AUTHOR]

This article describes how to identify allergic contact dermatitis resulting from hair dye, and outlines interventions and prevention principles for those who wish to continue dyeing their hair despite being allergic. Hair dye chemicals thought to be the most frequent sensitizers are discussed with instructions for health care providers on how to counsel patients about techniques to minimize exposure to allergenic substances. This framework should allow many patients to continue dyeing their hair without experiencing adverse side effects. [ABSTRACT FROM AUTHOR]

Background: p-Phenylenediamine (PPD) is an important hair dye allergen, but there remains a reasonable suspicion that other hair dye chemicals may also be responsible for a proportion of the clinical burden of hair dye allergy. Objective: To assess to what extent presently assessed additional patch test agents contribute to the diagnosis of non-PPD hair dye allergy. Methods: A retrospective analysis was conducted of patch test results with hair dye allergens, focusing on the extent to which patients who were positive for allergic reactions to other hair dye allergens also had a concomitant positive reaction to PPD. Results: For the hair dye allergens other than p-toluenediamine (PTD), reactions in the absence of a concomitant positive reaction to PPD were very rare. Positive reactors to PTD were also positive for reactions to PPD in 5 of every 6 cases. Pyrogallol positives often occurred in the absence of a PPD positive, but were never judged to be of clinical relevance. Conclusions: Hair dye chemicals other than PPD may be of importance, but the presently tested materials, with the possible exception of PTD, are normally positive only when a PPD-positive reaction is also present, suggesting that their use in patch testing in hair dye allergy is likely to be of limited value. [ABSTRACT FROM AUTHOR]