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Oral mucosal homeostasis is achieved by complex immunologic mechanisms, orchestrating host immunity to adapt to the physiologic functions of the various specialized niches in the oral cavity. Dental implants introduce a novel mucosal niche to the immune system to deal with. Nevertheless, the immune mechanisms engaged toward implants and whether they have broader effects are not well defined. Using a murine model, we found an accumulation of neutrophils and RANKL-expressing T and B lymphocytes in the implant-surrounding mucosa, accompanied by local bone loss. Surprisingly, the presence of implants had an impact on remote periodontal sites, as elevated inflammation and accelerated bone loss were detected in intact distant teeth. This was due to microbial dysbiosis induced by the implants, since antibiotic treatment prevented bone loss around teeth. However, antibiotic treatment failed to prevent the loss of implant-supporting bone, highlighting the distinct mechanisms mediating bone loss at each site. Further analysis revealed that implants induced chronic lymphocyte activation and increased mRNA expression of IFN-α and accumulation of IFN-α-producing plasmacytoid dendritic cells, which we previously reported as bone-destructive immune responses. Collectively, this study demonstrates that implants have a strong and broad impact on oral mucosal homeostasis, inducing periodontal bone loss in a niche-specific manner that is both microbiota dependent and independent. [ABSTRACT FROM AUTHOR]

Laryngeal chondrosarcomas are uncommon, and those that contain a distinct, nonchondroid, high-grade spindle cell sarcoma (the so-called "dedifferentiated" chondrosarcoma or chondrosarcoma with additional malignant mesenchymal component [CAMMC]) are extremely rare. Laryngeal CAMMC merit special attention, as CAMMC in other sites portends a poor prognosis. Eleven patients with laryngeal chondrosarcomas are reported on; 2 of these patients had CAMMC. On follow-up, 3 of the 11 patients had recurrences. The first had recurrence 4 and 11 years after tumor enucleation; that patient died disease free 2 years after salvage total laryngectomy. The second had recurrence 2 years after partial laryngectomy and was lost to follow-up after salvage total laryngectomy. The last patient recurred 13 years after partial laryngectomy and underwent salvage total laryngectomy; that patient was one of the two who developed CAMMC, and he also developed stomal recurrence of the "dedifferentiated" component 3 years after total laryngectomy. The other 8 patients are disease free after partial laryngectomy (6) or total laryngectomy (2) 10 months to 12 years later (mean: 51 months). This includes the 1 other patient with CAMMC, who is disease free 60 months after total laryngectomy. Laryngeal CAMMC has been shown, in at least one of the two patients, to be associated with a poor outcome. Patients with recurrent laryngeal chondrosarcomas do not have a poorer outcome after salvage total laryngectomy. The authors advocate partial laryngectomy if technically feasible. [ABSTRACT FROM AUTHOR]

Background: The rise in prevalence of atopic dermatitis (AD) has been correlated with numerous elements of the exposome, modern-day lifestyle, and familial history. The combined analysis of familial history and other risk elements may allow us to understand the driving factors behind the development of AD., Objective: To develop prediction models to assess the risk of developing AD using a large and diverse cohort (N = 77,525) and easily assessed risk factors., Methods: We analyzed electronic medical record data from Leumit Health System. Documented predictive factors include sex, season of birth, environment (urban/rural), socioeconomic status, household smoking, diagnosed skin conditions, number of siblings, a paternal, maternal, or sibling history of an atopic condition, and antibiotic prescriptions during pregnancy or after birth. Predictive models were trained and validated on the data set., Results: Medium (odds ratio [OR] 2.04, CI 1.92-2.17, P < .001) and high (OR 2.13, CI 1.95-2.34, P < .001) socioeconomic status, a previous diagnosis of contact dermatitis (OR 2.57, CI 2.37-2.78, P < .001), presence of siblings with an AD diagnosis (OR 2.21, CI 2.04-2.40, P < .001), and the percentage of siblings with any atopic condition (OR 2.58, CI 2.09-3.17, P < .001) drove risk for AD in a logistic regression model. A random forest prediction model with a sensitivity of 61% and a specificity of 84% was developed. Generalized mixed models accounting for the random effect of familial relationships boasted an area under the curve of 0.98., Conclusion: Predictive modeling using noninvasive and accessible inputs is a powerful tool to stratify risk for developing AD., (Copyright © 2024 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Pediatric food allergy remains commonplace, despite the advancement in our understanding of risk factors and prevention modalities for the condition. Early allergen introduction, a dietary intervention, has been endorsed by professional societies globally as an effective primary preventive measure, yet awareness among medical professionals and parents is lacking. Alongside food allergen introduction, overall nutrition, such as diet diversity, also plays an important role in allergy prevention. To address both food allergen introduction and overall nutrition, dietitians play a pivotal role in the dissemination and education of current guidelines to caregivers. This review addresses the particular role of the dietitian in food allergy prevention consultations, providing up-to-date information on food allergies, their development and prevalence, risk factors, dietary factors and an overview of the current guidelines in the United States. This has not been addressed in any of the current food allergy or nutrition guidelines.

Introduction: Darier disease is a rare inherited disease with dominant skin manifestations including keratotic papules and plaques on sebaceous and flexural areas. Secondary infection of skin lesions is common, and Staphylococcus aureus commonly colonizes these lesions. The aim of the study was to characterize the bacterial microbiome of cutaneous Darier lesions compared to normal-looking skin and disease severity., Methods: All patients with a history of Darier followed up at Emek Medical Center were invited to participate in the study. Patients that did not use antibiotics in the past month and signed informed consent had four skin sites sampled with swabs: scalp, chest, axilla, and palm. All samples were analyzed for bacterial microbiome using 16S rDNA sequencing., Results: Two hundred and eighty microbiome samples obtained from lesional and non-lesional skin of the scalp, chest, axilla, and palm of 42 Darier patients were included in the analysis. The most abundant bacterial genera across all skin sites were Propionibacterium, Corynebacterium, Paracoccus, Micrococcus, and Anaerococcus. Scalp and chest lesions featured a distinct microbiome configuration that was mainly driven by an overabundance of Staphylococci species. Patients with more severe disease exhibited microbiome alterations in the chest, axilla, and palm compared with patients with only mild disease, driven by Peptoniphilus and Moryella genera in scalp and palmar lesions, respectively., Conclusion: Staphylococci were significantly associated with Darier lesions and drove Darier-associated dysbiosis. Severity of the disease was associated with two other bacterial genera. Whether these associations also hold a causative role and may serve as a therapeutic target remains to be determined and requires further investigation., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Objective: Epidermolysis bullosa (EB) is a group of rare hereditary skin disorders characterized by the formation of painful blisters, erosions, and ulcers. In addition, the wounds can easily become infected with different pathogens. Therefore, the dynamics in the microbial populations across the various stages of EB can shed light on pathophysiology, the effect of treatment, and the factors involved in its recovery, but they are understudied. We thus sought to characterize the skin microbiome among patients with EB over time., Methods: A prospective study conducted in the pediatric dermatology clinic at Soroka Medical Center, Beer-Sheva, Israel. Children (0-18) with simplex and recessive dystrophic EB were sampled at two different time points: before a therapeutic regimen and 90 days (±14 days) later. Samples were obtained from lesional skin (wound), healthy, non-lesional skin, and seborrheic skin (forehead). Samples were subject to 16S rRNA amplicon sequencing. Analyses performed included comparisons of relative abundance at the phyla and genera taxonomic levels, alpha and beta diversity comparisons, and differential abundance., Results: 32 children with EB were enrolled, for whom 192 skin microbiome samples were obtained. Lesional skin samples harbored significantly less Bacteroidota and Fusobacteriota before the initiation of treatment. Following topical dressing, we observed more Firmicutes and less Proteobacteria in lesional skin samples than healthy and seborrheic skin samples. In addition, Staphylococcus was significantly more abundant in lesional samples than in non-lesional and seborrheic samples following treatment., Conclusions: Our study recaptured the reduced bacterial diversity and increased staphylococcal carriage in EB patients, showing a potential effect of topical dressing either directly on the wound microbiome or indirectly through the contribution towards skin healing. The detection of Firmicutes in general, and S. aureus specifically, commensurate with the application of a wound dressing may warrant the use of additional treatment methods to facilitate wound healing. Future studies in these patients should prospectively correlate the temporal changes in the microbiome associated with various treatment modalities in order to optimize the care of EB patients.

Background: The Learning Early About Peanut Allergy or LEAP trial found that the early introduction of peanuts in the diet of infants at risk for peanut allergies prevents peanut allergy. The effect of maternal consumption of peanuts on subsequent peanut sensitization or peanut allergy in the LEAP trial has not been studied to date., Objective: To determine whether maternal consumption of peanut protein while breastfeeding protects against peanut-allergic outcomes in the absence of peanut consumption in infants., Methods: We performed an analysis of the data from the peanut avoidance arm of the LEAP study to discern the effects of maternal consumption of peanuts while pregnant and breastfeeding on an infant's peanut-allergic outcomes., Results: Of the 303 infants in the avoidance group, 31 mothers consumed more than 5 g of peanut per week, 69 consumed less than 5 g of peanut per week and 181 did not consume peanut while breastfeeding. Peanut sensitization (P = .03) and peanut allergy (P = .07) occurred less frequently in infants whose mothers consumed a moderate amount of peanuts while breastfeeding when compared with those who either did not consume peanuts while breastfeeding or those who consumed a large amount of peanuts when breastfeeding. Ethnicity (odds ratio [OR], 0.47; P = .046, 95% confidence interval [CI], 0.22-0.99), baseline peanut skin prick test stratum (OR, 4.87; P < .001, 95% CI, 2.13-11.12), no maternal peanut consumption while breastfeeding (OR, 3.25; P = .008, 95% CI, 1.36-7.77), and baseline SCORing Atopic Dermatitis greater than 40 (OR, 2.78; P = .007, 95% CI, 1.32-5.85) were all significant contributors to peanut sensitization or allergy at 60 months of age., Conclusion: Moderate consumption (<5 grams per week) of peanuts while breastfeeding provides a significant protective effect against peanut sensitization and a noticeable but not statistically significant protective effect against peanut allergy later on in life in high-risk infants in the context of delayed peanut introduction., (Copyright © 2023 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

The bacterial community that colonizes the human face imparts physiochemical and physiological effects on the facial skin. These skin-microbe interactions impact dermatological, cosmetic and skincare applications due to the centrality of the human face in daily interactions. However, fine-scale characterization of the human face skin microbiome is lacking. Using 16S rRNA sequencing and 3D cartography, this study plotted and characterized the facial skin microbiome in high- definition, based on 1,649 samples from 12 individuals. Analysis yielded a number of novel insights, including that of the relative uniformity of skin microbiome composition within skin sites, site localization of certain microbes, and the interpersonal variability of the skin microbiome. The results show that high-resolution topographical mapping of the skin microbiome is a powerful tool for studying the human skin microbiome. Despite a decade of skin microbiome research, there is still much to be discovered.

Background: The evolutionary relationships between plants and their microbiomes are of high importance to the survival of plants in general and even more in extreme conditions. Changes in the plant's microbiome can affect plant development, growth, fitness, and health. Along the arid Arava, southern Israel, acacia trees ( Acacia raddiana and Acacia tortilis ) are considered keystone species. In this study, we investigated the ecological effects of plant species, microclimate, phenology, and seasonality on the epiphytic and endophytic microbiome of acacia trees. One hundred thirty-nine leaf samples were collected throughout the sampling year and were assessed using 16S rDNA gene amplified with five different primers (targeting different gene regions) and sequenced (150 bp paired-end) on an Illumina MiSeq sequencing platform. Results: Epiphytic bacterial diversity indices (Shannon-Wiener, Chao1, Simpson, and observed number of operational taxonomic units) were found to be nearly double compared to endophyte counterparts. Epiphyte and endophyte communities were significantly different from each other in terms of the composition of the microbial associations. Interestingly, the epiphytic bacterial diversity was similar in the two acacia species, but the canopy sides and sample months exhibited different diversity, whereas the endophytic bacterial communities were different in the two acacia species but similar throughout the year. Abiotic factors, such as air temperature and precipitation, were shown to significantly affect both epiphyte and endophytes communities. Bacterial community compositions showed that Firmicutes dominate A. raddiana , and Proteobacteria dominate A. tortilis ; these bacterial communities consisted of only a small number of bacterial families, mainly Bacillaceae and Comamonadaceae in the endophyte for A. raddiana and A. tortilis , respectively, and Geodematophilaceae and Micrococcaceae for epiphyte bacterial communities, respectively. Interestingly, ~60% of the obtained bacterial classifications were unclassified below family level (i.e., "new"). Conclusions: These results shed light on the unique desert phyllosphere microbiome highlighting the importance of multiple genotypic and abiotic factors in shaping the epiphytic and endophytic microbial communities. This study also shows that only a few bacterial families dominate both epiphyte and endophyte communities, highlighting the importance of climate change (precipitation, air temperature, and humidity) in affecting arid land ecosystems where acacia trees are considered keystone species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Al Ashhab, Meshner, Alexander-Shani, Dimerets, Brandwein, Bar-Lavan and Winters.)

Dead Sea climatotherapy (DSC) is a well-established therapeutic modality for the treatment of several diseases, including atopic dermatitis. Skin microbiome studies have shown that skin microbiome diversity is anticorrelated with both atopic dermatitis severity and concurrent Staphylococcus aureus overgrowth. This study aimed to determine whether DSC induces skin microbiome changes concurrent with clinical improvements in atopic dermatitis. We sampled 35 atopic dermatitis patients and ten healthy controls on both the antecubital and popliteal fossa. High-resolution microbial community profiling was attained by sequencing multiple regions of the 16S rRNA gene. Dysbiosis was observed in both lesional and nonlesional sites, which was partially attenuated following treatment. Severe AD skin underwent the most significant community shifts, and Staphylococcus epidermidis, Streptococcus mitis and Micrococcus luteus relative abundance were significantly affected by Dead Sea climatotherapy. Our study highlights the temporal shifts of the AD skin microbiome induced by Dead Sea climatotherapy and offers potential explanations for the success of climatotherapy on a variety of skin diseases, including AD., (© 2019 American Society for Photobiology.)

Bacterial commensal colonization of human skin is vital for the training and maintenance of the skin's innate and adaptive immune functions. In addition to its physical barrier against pathogen colonization, the skin expresses a variety of antimicrobial peptides (AMPs) which are expressed constitutively and induced in response to pathogenic microbial stimuli. These AMPs are differentially effective against a suite of microbial skin colonizers, including both bacterial and fungal residents of the skin. We review the breadth of microorganism-induced cutaneous AMP expression studies and their complementary findings on the efficacy of skin AMPs against different bacterial and fungal species. We suggest further directions for skin AMP research based on emerging skin microbiome knowledge in an effort to advance our understanding of the nuanced host-microbe balance on human skin. Such advances should enable the scientific community to bridge the gap between descriptive disease-state AMP studies and experimental single-species in vitro studies, thereby enabling research endeavors that more closely mimic the natural skin environs.

Laryngeal/hypopharyngeal liposarcomas are very rare, fewer than 40 cases have been reported. These tumors are polypoid, with a male predisposition, and usually cause hoarseness and difficulty breathing. Their clinical course is characterized by multiple local recurrences. No distant metastasis has been reported, and dedifferentiation is extremely rare. In sum, the prognosis of these tumors is excellent; the 5-year survival rate is essentially 100 %. Pathologic diagnosis of these well-differentiated liposarcomas can be challenging. Many of them were initially diagnosed as benign lipoma, fibrovascular polyp, or "inflammatory polyp". The correct diagnosis is usually made after multiple recurrences. On the other hand, the literature bears out that these incorrect diagnoses do not impact disease-specific survival. Here, we report three patients with laryngeal/hypopharyngeal well-differentiated liposarcomas; this is the first documentation of MDM2 amplification in liposarcomas at this site.

The human skin microbiome plays an important role in both health and disease. Microbial biofilms are a well-characterized mode of surface-associated growth, which present community-like behaviors. Additionally, biofilms are a critical element in certain skin diseases. We review how the perception of the resident skin microbiota has evolved from the early linkages of certain microbes to disease states, to a more comprehensive and intricate understanding brought on by biofilm and microbiome revelations. Rapidly expanding arsenals of experimental methods are opening new horizons in the study of human-microbe and microbe-microbe interactions. Microbial community profiling has largely remained a separate discipline from that of biofilm research, yet the introduction of metatranscriptomics, metabolomics, and the ability to distinguish between dormant and active members of a community have all paved the road toward a convergent cognizance of the encounter between these two microbial disciplines.

Various surfaces associated with the storage and packing of food are known to harbor distinct bacterial pathogens. Conspicuously absent among the plethora of studies implicating food packaging materials and machinery is the study of corrugated cardboard packaging, the worldwide medium for transporting fresh produce. In this study, we observed the microbial communities of three different store-bought fruits and vegetables, along with their analog cardboard packaging using high throughput sequencing technology. We further developed an anti-biofilm polymer meant to coat corrugated cardboard surfaces and mediate bacterial biofilm growth on said surfaces. Integration of a novel thiazolidinedione derivative into the acrylic emulsion polymers was assessed using Energy Dispersive X-ray Spectrometry (EDS) analysis and surface topography was visualized and quantified on corrugated cardboard surfaces. Biofilm growth was measured using q-PCR targeting the gene encoding 16s rRNA. Additionally, architectural structure of the biofilm was observed using SEM. The uniform integration of the thiazolidinedione derivative TZD-6 was confirmed, and it was determined via q-PCR to reduce biofilm growth by ~80% on tested surfaces. A novel and effective method for reducing microbial load and preventing contamination on food packaging is thereby proposed.

Background: Clear cell odontogenic carcinoma (CCOC), which has been described within the past 2 decades, is a rare odontogenic tumor that tends to occur in the mandible of older adults, with a predilection for women. It is potentially aggressive and capable of multiple local recurrences and locoregional and distant metastases., Objectives: To report the clinicopathologic findings and follow-up of a case of CCOC and to review the literature., Design: Case report and literature review., Main Outcome Measurements: Findings from histologic analysis, immunohistochemistry, and electron microscopy., Results: An 81-year-old woman experienced 3 locoregional recurrences within 21 months of initial therapy. She is presently disease free, 4.5 years after initial resection, having received multiple resections and adjuvant radiotherapy., Conclusions: The diagnosis of CCOC must be considered in the differential diagnosis of jaw tumors with a clear cell component. For these tumors, resection with negative margins is the treatment of choice because more conservative surgery (eg, curettage) inevitably results in recurrence and/or metastasis. Adjuvant radiotherapy is a rational option for tumors that have eroded cortex.

Plexiform fibrohistiocytic tumor (PFT) is a low-grade, superficial, soft tissue neoplasm with a limited but significant ability to metastasize. This type of tumor only rarely presents in the skin of the head and neck. Clinicians first encountering young patients with facial neoplasia, such as a PFT, might be unaware of its exact oncologic potential and instead be primarily concerned with the cosmetic outcome. We treated a 17-year-old boy with a PFT on his cheek who was initially treated only by shave biopsy. The tumor subsequently recurred and metastasized to the cervical lymph nodes 3 years after the initial biopsy. Therefore, appropriate initial therapy for PFT requires complete excision with negative resection margins.

Context: Primary salivary clear cell tumors comprise an uncommonly encountered subgroup of salivary neoplasia. We hypothesize that clear cell carcinoma does not represent a "monomorphic" variant of epithelial-myoepithelial carcinoma, but is distinct in terms of histogenesis and tumor biology., Objectives: To compare the clinicopathologic features of 20 cases of salivary primary clear cell tumors, including 12 clear cell carcinomas (CCCs), 7 epithelial-myoepithelial carcinomas (EMECs), and 1 clear cell myoepithelial carcinoma (CCMEC); to investigate their interrelationship with regard to myoepithelial differentiation; and to offer a diagnostic approach for distinguishing between these entities., Design: Retrospective and prospective identification and review of patients diagnosed with primary salivary clear cell neoplasia and review of the English language literature., Setting: Three academic tertiary-care hospitals., Patients: We identified 12 patients with CCC, 7 with EMEC, and 1 with CCMEC. Patients included 11 men and 9 women, aged 30 to 88 years (median 72.5 years)., Main Outcome Measures: Immunohistochemical reactivity for S100, muscle-specific actin, and calponin; ultrastructural examination when feasible; review of patient charts; and telephone interviews to establish clinical outcome., Results: Clear cell carcinoma has a predilection for intraoral sites, whereas EMEC has a predilection for the parotid. All 3 of the tumor types studied have a propensity for locoregional recurrence, which can manifest decades after initial surgery. There were no mortalities among patients with CCC, even after pulmonary metastasis in 2 patients, confirming the indolent nature of this group of clear cell tumors. A meta-analysis of reported cases of CCC, EMEC, and CCMEC confirmed that EMEC and CCMEC have a much greater propensity for locoregional recurrence than CCC, despite the predilection of both for a more surgically accessible site (parotid). We found no definitive evidence of myoepithelial differentiation in CCC, indicating that it is probably morphogenetically distinct from EMEC and CCMEC, both tumors with diagnostically requisite myoepithelial differentiation., Conclusions: The initial treatment of choice for CCC, CCMEC, and EMEC is surgical resection with negative margins. Locoregional recurrence should be treated aggressively, as it is still consistent with long disease-free intervals. The lack of myoepithelial differentiation in CCC is consistent with the concept that this tumor is histomorphogenically distinct from EMEC and that it is not merely a monomorphic variant.

Background: Few sinonasal malignancies can manifest, histologically, as clear cell neoplasia. The most likely such tumor to be encountered is metastatic renal cell carcinoma. Primary sinonasal tumors that can appear as clear cell malignancies include squamous cell carcinoma and mucoepidermoid carcinoma. Primary salivary clear cell carcinoma occurs almost exclusively in the oral cavity and has not been described in the nasal cavity., Objective: To report a unique sinonasal clear cell malignancy that mimicked metastatic renal carcinoma., Study Design: Case report., Outcome Measurements: Radiography, histology, histochemistry, immunohistochemistry, and electron microscopy., Results: Histologically, the tumor was identical to renal cell carcinoma. No evidence of renal malignancy was found by abdominal computed tomographic scan or gadolinium-enhanced magnetic resonance imaging. Histochemistry confirmed the presence of tumor glycogen but no mucin. Immunohistochemistry confirmed strong expression of low- and high-molecular-weight keratin and S100, and no vimentin expression. Electron microscopy showed tumor myofibroblastic differentiation and cytoplasmic glycogen, neutral lipid vacuoles, and cholesterol., Conclusions: There was no clinical evidence of renal cell carcinoma. The immunohistochemical and ultrastructural findings were inconsistent with the diagnosis of renal cell carcinoma and showed features also inconsistent with the diagnosis of primary salivary clear cell carcinoma. We therefore conclude that this tumor represents a new and distinct entity, notable in its presentation as a "counterfeit renal cell carcinoma."

Background: The incidental discovery of thyroid lesions in lymph nodes during a lymph node dissection performed for a separate primary head and neck tumor is an unusual clinical entity. Its discovery has led to controversy regarding its significance and management., Methods: We identified five patients over the years 1991-1999 with this finding. All five patients were subsequently treated with a total thyroidectomy and a level VI lymph node dissection., Results: Pathological examination revealed three papillary carcinomas and level VI lymph node metastases in the two patients who had carcinoma in their thyroid glands. All five patients are presently free of their primary and thyroid disease on follow-up examinations., Conclusions: These patients should be addressed with additional work-up and surgery if metastatic thyroid cancer is documented in the lymph node. We offer a diagnostic algorithm that may aid in further work-up and treatment in these unusual cases., (Copyright 2001 John Wiley & Sons, Inc. Head Neck 23: 885-891, 2001.)