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Methods in Molecular Biology (Clifton,... 2022Tissue processing is the technique by which fixed tissues are made suitable for embedding within a supportive medium such as paraffin, and consists of three sequential...
Tissue processing is the technique by which fixed tissues are made suitable for embedding within a supportive medium such as paraffin, and consists of three sequential steps: dehydration, clearing, and infiltration. In most clinical and research settings, tissue processing is accomplished using an automated tissue processor, with or without microwave-assistance. To ensure high-quality results, processing protocols should be tailored to tissue size and composition by modifying variables such as reagents used and the timing of the various steps. Herein, we provide an overview of tissue processing theory and outline a basic tissue processing method for use with a conventional automated fluid transfer/enclosed processor. The principles described will assist readers in optimizing tissue processing for their own projects.
Topics: Microwaves; Paraffin; Paraffin Embedding; Specimen Handling; Tissue Fixation
PubMed: 34859398
DOI: 10.1007/978-1-0716-1948-3_4 -
International Journal of Biometeorology Aug 2021Data on the efficacy of treatment modalities in De Quervain's tenosynovitis (DQT) is limited. Paraffin therapy is routinely used in treating hand osteoarthritis and... (Randomized Controlled Trial)
Randomized Controlled Trial
Data on the efficacy of treatment modalities in De Quervain's tenosynovitis (DQT) is limited. Paraffin therapy is routinely used in treating hand osteoarthritis and neuropathies. However, there are not enough studies investigating paraffin effectiveness. This study evaluates the effectiveness of paraffin bath therapy on pain, functional status, muscle strength, and quality of life in patients with DQT. This prospective, single-blind, randomized, controlled study enrolled 51 DQT patients. Group 1 (n = 26) received paraffin bath + splint + exercise; Group 2 (n = 25) received splint + exercise therapy. Pain, handgrip strength, thumb palmar pinch strength, functional status, and quality of life were evaluated. Both treatment combinations improved pain, grip strength, palmar pinch strength of the thumb, functional status, and quality of life. The paraffin group provided more effective pain control than the paraffin-free group and was more effective in improving functional status, handgrip strength, and quality of life (p < 0.05). Apparently, adding paraffin therapy to the combination of the splint and therapeutic exercise positively affects the patient's treatment outcomes. For this reason, paraffin therapy should be included in the conservative treatment combinations in DQT.
Topics: De Quervain Disease; Hand Strength; Humans; Paraffin; Prospective Studies; Quality of Life; Single-Blind Method; Tenosynovitis
PubMed: 33675398
DOI: 10.1007/s00484-021-02111-2 -
European Urology Focus Sep 2019Penile paraffinoma is a rare cause of penile mass that can occur following injection of liquid paraffin, performed illicitly for penile augmentation. Over the past 2 yr,... (Review)
Review
Penile paraffinoma is a rare cause of penile mass that can occur following injection of liquid paraffin, performed illicitly for penile augmentation. Over the past 2 yr, we have observed an increasing number of cases presenting with the complications of penile paraffinoma; three patients of central European origin have required inpatient treatment at our institution and posed a significant management dilemma. This mini-review aims to review the literature on the aetiopathogenesis, clinical features, diagnosis, and management of penile paraffinoma. A systematic search of PubMed and Scopus was performed with 10 case series and 26 case reports identified between 1956 and 2017. A total of 124 cases, with a mean age of 36.29 yr, were identified. The majority originated in Korea, and the most common injected material was liquid paraffin (80.6%). Patients presented with pain/swelling, ulceration/fistulae, and penile deformity. The majority required surgical excision of paraffinoma followed by reconstruction with a variety of procedures including split skin grafting, scrotal skin flap reconstruction, and prepuce grafting. Mean duration of follow-up was 15.8 mo. Penile paraffinoma remains a rare presentation; however, it can present management difficulties. We have had an increase in cases, with three patients presenting with complications following injection of paraffin in our unit in the past 2 yr. Definitive management includes surgical excision and reconstruction as required with early involvement of plastic surgeons. There may be a role for conservative management; however, long-term outcomes are unclear. There may be a need for targeted preventative measures through public health agencies in communities where the practice is more prevalent. PATIENT SUMMARY: Penile paraffinoma can occur following injection of liquid paraffin or similar substances, generally used by non-healthcare personnel for the purpose of penile augmentations, and can cause significant pain, ulceration, and penile deformity. Definitive management includes surgical excision with reconstruction as required. Prevention of its use through awareness and education may be required in communities where the practice is more common.
Topics: Body Modification, Non-Therapeutic; Foreign Bodies; Humans; Injections; Male; Paraffin; Penile Diseases
PubMed: 30007541
DOI: 10.1016/j.euf.2018.06.013 -
Clinical and Experimental Dermatology Jun 2022Eczema (atopic dermatitis; AD) is a very common itchy skin condition affecting 1 in 5 children and up to 1 in 10 adults worldwide. The skin of eczema sufferers is prone... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Eczema (atopic dermatitis; AD) is a very common itchy skin condition affecting 1 in 5 children and up to 1 in 10 adults worldwide. The skin of eczema sufferers is prone to redness, irritation and dryness because it does not form an effective barrier, i.e. the ability of the skin to stop irritants, allergens and microorganisms getting into the body. Skin barrier dysfunction is a hallmark of AD. The regular and liberal (600 g/week for an adult) use of emollients is recommended for all patients with eczema), even between episodes of itching and redness, to soften and soothe the skin. In England alone, almost 9 million prescriptions for emollient creams were issued in 2018, at a cost of over £50 million. Despite this widespread use, relatively little is known about how commonly prescribed emollient creams affect the skin's barrier, and thus the role of moisturizers in AD development and progression remains unclear. We set out to compare three different types of emollient cream and a no-treatment control.
AIM
To compare the barrier-strengthening properties of a new moisturizer containing urea and glycerol (urea-glycerol cream; UGC), with those of a glycerol-containing moisturizer (glycerol cream; GC), a simple paraffin cream (PC) with no humectant, and a no-treatment control (NTC).
METHODS
This was an observer-blinded prospective Phase 2 within-subject multilateral single-centre randomized controlled trial in adults with AD (Clinical Trials #NCT03901144). The intervention involved 4 weeks of treatment, twice daily, with the three products applied to one of four areas on the forearms the (the fourth area was the untreated control, randomized allocation). Skin properties [dryness, transepidermal water loss (TEWL), hydration and natural moisturizing factor (NMF) levels] were assessed before, during and after treatment to see what happened to the skin's barrier. The primary outcome was skin sensitivity to the irritant sodium lauryl sulfate (SLS) after treatment. We performed tests on the skin before and after treatment to see what happened to the skin's barrier.
RESULTS
In total, 49 patients were randomized, completed treatment and included in the analysis. UGC significantly reduced the response to SLS as indicated by a reduction in TEWL compared with NTC (-9.0 g/m /h; 95% CI -12.56 to -5.49), with PC (-9.0 g/m /h; 95% CI -12.60 to -5.44) and with GC -4.2 g/m /h; 95% CI 7.76 to -0.63). Skin moisturization improved at sites treated with UGC compared with NTC and PC, and this was accompanied by concordant changes in dryness and NMF levels. Subgroup analysis suggested FLG-dependent enhancement of treatment effects.
CONCLUSION
The study showed that not all emollient creams for eczema are equal. The simple paraffin-based emollient, which represents the most widely prescribed type of emollient cream in England, had no effect on the skin's barrier and reduced the skin's NMF. UGC markedly improved the skin's barrier and protected against irritation. GC performed better than PC, but not as well as UGC. UGC strengthened the skin barrier through a mechanism involving increased NMF levels in the skin, and imparted protection from SLS-induced irritation. By helping correct a major pathophysiological process, UGC has the potential to improve the long-term control of AD. The results show that different emollient creams have different effects on our skin, and only certain types have the ability to improve the skin's barrier and protect against irritants that trigger eczema.
Topics: Adult; Child; Dermatitis, Atopic; Eczema; Emollients; Glycerol; Humans; Irritants; Paraffin; Prospective Studies; Pruritus; Skin Cream; Urea; Water Loss, Insensible
PubMed: 35167133
DOI: 10.1111/ced.15141 -
JAMA Oncology Aug 2023Xerostomia is a major toxic effect associated with intensity-modulated radiotherapy (IMRT) for oropharyngeal cancers.
Weekly Adaptive Radiotherapy vs Standard Intensity-Modulated Radiotherapy for Improving Salivary Function in Patients With Head and Neck Cancer: A Phase 3 Randomized Clinical Trial.
IMPORTANCE
Xerostomia is a major toxic effect associated with intensity-modulated radiotherapy (IMRT) for oropharyngeal cancers.
OBJECTIVE
To assess whether adaptive radiotherapy (ART) improves salivary function compared with IMRT in patients with head and neck cancer.
DESIGN, SETTING, AND PARTICIPANTS
This phase 3 randomized clinical trial was conducted in 11 French centers. Patients aged 18 to 75 years with stage III-IVB squamous cell oropharyngeal cancer treated with chemoradiotherapy were enrolled between July 5, 2013, and October 1, 2018. Data were analyzed from November 2021 to May 2022.
INTERVENTIONS
The patients were randomly assigned (1:1) to receive standard IMRT (without replanning) or ART (systematic weekly replanning).
MAIN OUTCOMES AND MEASURES
The primary end point was the frequency of xerostomia, measured by stimulating salivary flow with paraffin. Secondary end points included salivary gland excretory function measured using technetium-99m pertechnetate scintigraphy, patient-reported outcomes (Eisbruch xerostomia-specific questionnaire and the MD Anderson Symptom Inventory for Head and Neck Cancer questionnaire), early and late toxic effects, disease control, and overall and cancer-specific survival.
RESULTS
A total of 132 patients were randomized, and after 1 exclusion in the ART arm, 131 were analyzed: 66 in the ART arm (mean [SD] age at inclusion, 60 [8] years; 57 [86.4%] male) and 65 in the standard IMRT arm (mean [SD] age at inclusion, 60 [8] years; 57 [87.7%] male). The median follow-up was 26.4 months (IQR, 1.2-31.3 months). The mean (SD) salivary flow (paraffin) at 12 months was 630 (450) mg/min in the ART arm and 584 (464) mg/min in the standard arm (P = .64). The mean (SD) excretory function of the parotid gland at 12 months, measured by scintigraphy, improved in the ART arm (48% [17%]) compared with the standard arm (41% [17%]) (P = .02). The 2-year-overall survival was 76.9% (95% CI, 64.7%-85.4%) in both arms.
CONCLUSIONS AND RELEVANCE
This randomized clinical trial did not demonstrate a benefit of ART in decreasing xerostomia compared with standard IMRT. No significant differences were found in secondary end points except for parotid gland excretory function, as assessed by scintigraphy, or in survival rates.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT01874587.
Topics: Humans; Male; Female; Radiotherapy, Intensity-Modulated; Paraffin; Head and Neck Neoplasms; Xerostomia; Parotid Gland; Oropharyngeal Neoplasms
PubMed: 37261806
DOI: 10.1001/jamaoncol.2023.1352 -
Revista Internacional de Andrologia 2021A fifty-year-old healthy, Portuguese male, with prior history of paraffin injections into the penis 30 years ago, was referred for urological consultation because of a...
A fifty-year-old healthy, Portuguese male, with prior history of paraffin injections into the penis 30 years ago, was referred for urological consultation because of a large, hardened ulcerated mass on the base of the penis causing deformity and pain. The patient underwent a biopsy that showed a benign granulomatous lesion, and then excision of the mass and penile plasty with a scrotum flap in the same surgical time. Histology confirmed the diagnosis of paraffinoma. Three months after surgery, the patient is satisfied with the functional (urinary function and erectile function) and aesthetic results. Penile paraffinoma is a rare disease (most common in Asia and Eastern Europe) and results from an inflammatory response to the subcutaneous injection of paraffin, Vaseline or other mineral oils. Treatment is usually surgery.
Topics: Granuloma; Humans; Injections, Subcutaneous; Male; Middle Aged; Paraffin; Penile Diseases; Penis; Plastic Surgery Procedures; Skin Ulcer; Surgical Flaps; Treatment Outcome
PubMed: 32778451
DOI: 10.1016/j.androl.2020.01.006 -
Pediatric Dermatology 2023Moisturizers are first-line therapy for treatment of atopic dermatitis (AD). Although there are multiple types of moisturizers available, head-to-head trials between... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Moisturizers are first-line therapy for treatment of atopic dermatitis (AD). Although there are multiple types of moisturizers available, head-to-head trials between different moisturizers are limited.
OBJECTIVE
To evaluate if a paraffin-based moisturizer is as effective as ceramide-based moisturizer in children with AD.
MATERIALS AND METHODS
In this double-blind, randomized comparative trial of pediatric patients with mild to moderate AD, subjects applied either a paraffin-based or ceramide-based moisturizer twice daily. Clinical disease activity using SCOring Atopic Dermatitis (SCORAD), quality of life using Children/Infants Dermatology Life Quality Index (CDLQI/IDLQI), and transepidermal water loss (TEWL) were measured at baseline and at follow-up at 1, 3, and 6 months.
RESULTS
Fifty-three patients were recruited (27 ceramide group and 26 paraffin group) with a mean age of 8.2 years and mean disease duration of 60 months. The mean change in SCORAD at 3 months in the ceramide-based and paraffin-based moisturizer groups was 22.1 and 21.4, respectively (p = .37). The change in CDLQI/IDLQI, TEWL over forearm and back, amount and days of topical corticosteroid required, median time to remission and disease-free days at 3 months were similar in both groups. As the 95% confidence interval (CI) of mean change in SCORAD at 3 months in both groups (0.78, 95% CI: -7.21 to 7.52) was not within the predefined margin of equivalence (-4 to +4), the conclusion of equivalence could not be proven.
CONCLUSION
Both the paraffin-based and ceramide-based moisturizers were comparable in improving the disease activity in children with mild to moderate AD.
Topics: Infant; Child; Humans; Dermatitis, Atopic; Emollients; Paraffin; Ceramides; Quality of Life; Treatment Outcome; Double-Blind Method; Severity of Illness Index
PubMed: 37269189
DOI: 10.1111/pde.15355 -
Environmental Science & Technology Aug 2023Chlorinated paraffins (CPs) are ubiquitous in the environment due to their large-scale usage, persistence, and long-range atmospheric transport. The oceans are a... (Review)
Review
Chlorinated paraffins (CPs) are ubiquitous in the environment due to their large-scale usage, persistence, and long-range atmospheric transport. The oceans are a critical environment where CPs transformation occurs. However, the broad impacts of CPs on the marine environment remain unclear. This review describes the sources, occurrence and transport pathways, environmental processes, and ecological effects of CPs in the marine environment. CPs are distributed in the global marine environment by riverine input, ocean currents, and long-range atmospheric transport from industrial areas. Environmental processes, such as the deposition of particle-bound compounds, leaching of plastics, and microbial degradation of CPs, are the critical drivers for regulating CPs' fate in water columns or sediment. Bioaccumulation and trophic transfer of CPs in marine food webs may threaten marine ecosystem functions. To elucidate the biogeochemical processes and environmental impacts of CPs in marine environments, future work should clarify the burden and transformation process of CPs and reveal their ecological effects. The results would help readers clarify the current research status and future research directions of CPs in the marine environment and provide the scientific basis and theoretical foundations for the government to assess marine ecological risks of CPs and to make policies for pollution prevention and control.
Topics: Ecosystem; Paraffin; Hydrocarbons, Chlorinated; Environmental Pollution; Food Chain; Environmental Monitoring; China
PubMed: 37503949
DOI: 10.1021/acs.est.3c02316 -
Environmental Science & Technology Nov 2023Polychlorinated dibenzo--dioxins and dibenzofurans (PCDD/Fs) and short-chain chlorinated paraffins (SCCPs) can be formed during the production of chlorinated paraffins...
Polychlorinated dibenzo--dioxins and dibenzofurans (PCDD/Fs) and short-chain chlorinated paraffins (SCCPs) can be formed during the production of chlorinated paraffins (CPs). Detection and accurate quantification of PCDD/Fs in CPs are challenging because of their matrix complexity. Therefore, the occurrence and formation mechanisms of PCDD/Fs from CPs have not been studied extensively in the past. In this study, 15 commercial samples including solid and liquid CPs were collected in 2022 from China. The average ΣSCCP concentrations detected in the solid and liquid CPs were 158 and 137 mg/g, respectively. The average International Toxic Equivalent (I-TEQ) values of 2,3,7,8-PCDD/F in solid and liquid CPs were 15.8 pg I-TEQ/g and 15.0 pg I-TEQ/g, respectively. The solid and liquid CPs had different predominant congener groups for SCCPs and PCDD/Fs. Possible formation routes for the generation of PCDD/Fs were analyzed by screening precursors in paraffin and laboratory-scale thermochemical experiments of CPs. The transformation between 2,3,7,8-PCDD/Fs and non-2,3,7,8-PCDD/Fs was recognized by calculating the successive chlorination preference. The first reported occurrence of PCDD/Fs in CP commercial products indicated that exposure to CPs and downstream products might be an assignable source of PCDD/F emission, which is of great significance to further explore the control factors of PCDD/Fs in the whole life cycle of CPs.
Topics: Polychlorinated Dibenzodioxins; Paraffin; Dibenzofurans; Dibenzofurans, Polychlorinated; Benzofurans; Mineral Oil; China; Environmental Monitoring; Dioxins
PubMed: 37905521
DOI: 10.1021/acs.est.3c06378 -
The Journal of Physical Chemistry. B Feb 2022Paraffin wax deposition has long been a vexing problem in industry. Especially, in offshore oil production, paraffin wax deposits and clogs pipes and containers because...
Paraffin wax deposition has long been a vexing problem in industry. Especially, in offshore oil production, paraffin wax deposits and clogs pipes and containers because of low temperature, causing severe economic loss. It has been known that the crystallization of n-alkanes mainly causes the deposition of paraffin wax, which is necessary to understand the mechanism of the crystallization behavior of paraffin wax. We solve the challenge of describing the crystallization behavior of the alkane mixture system and evaluate the contributions of every carbon atom to crystallization based on the occupied volume, structure entropy, and order parameter. These results demonstrate that the middle atoms are the main contributor to crystallization, and the end atoms of n-alkanes are unfavorable for the crystallization of n-alkanes, showing that increasing the number of end atoms, for example, adding branched alkanes, will hinder the crystallization of paraffin wax. Furthermore, perhydrosqualene is chosen to study the inhibition of crystallization by adding branched alkanes. As there are different properties between the end and the middle atoms, based on the principle of dissolution with similar properties, a small number of branched alkanes will promote crystallization. Also, an inhibitory effect of the end atoms is observed when the proportion of branched alkanes increases to a certain percentage. Our simulation work describes the crystallization behavior of paraffin wax in detail, providing theoretical assistance for preventing and controlling paraffin deposition.
Topics: Alkanes; Carbon; Crystallization; Paraffin; Waxes
PubMed: 35077173
DOI: 10.1021/acs.jpcb.1c10000