Obstructive Sleep Apnea and Risk of Postoperative Complications after Non-Cardiac Surgery.

Obstructive sleep apnea (OSA), a common sleep disorder, poses significant challenges in perioperative management due to its complexity and multifactorial nature. With a global prevalence of approximately 22.6%, OSA often remains undiagnosed, and increases the risk of cardiac and respiratory postoperative complications. Preoperative screening has become essential in many institutions to identify patients at increased risk, and experts recommend proceeding with surgery in the absence of severe symptoms, albeit with heightened postoperative monitoring. Anesthetic and sedative agents exacerbate upper airway collapsibility and depress central respiratory activity, complicating intraoperative management, especially with neuromuscular blockade use. Additionally, OSA patients are particularly prone to opioid-induced respiratory depression, given their increased sensitivity to opioids and heightened pain perception. Thus, regional anesthesia and multimodal analgesia are strongly advocated to reduce perioperative complication risks. Postoperative care for OSA patients necessitates vigilant monitoring and tailored management strategies, such as supplemental oxygen and Positive Airway Pressure therapy, to minimize cardiorespiratory complications. Health care institutions are increasingly focusing on enhanced monitoring and resource allocation for patient safety. However, the rising prevalence of OSA, heterogeneity in disease severity, and lack of evidence for the efficacy of costly perioperative measures pose challenges. The development of effective screening and monitoring algorithms, alongside reliable risk predictors, is crucial for identifying OSA patients needing extended postoperative care. This review emphasizes a multidimensional approach in managing OSA patients throughout the perioperative period, aiming to optimize patient outcomes and minimize adverse outcomes.

Adherence to Masking Requirement During the COVID-19 Pandemic by Early Elementary School Children.

BACKGROUND: Top public health experts and organizations strongly recommend universal masking for children older than 2 years old during the COVID-19 pandemic, but speculate it may be difficult for young children. This study sought to assess the usage of cloth face masks in grades pre-K-2 and identify associated characteristics and adverse events. It is the first data to assess mask wearing by young children in school. METHODS: This online, prospective, observational, survey in multiple schools within a single school district in a major metropolitan area measured adherence to face covering mandates by students in grades pre-K-2 as measured by percentage of day with appropriate face mask wearing per report via daily teacher surveys for the first 4 weeks of school. RESULTS: The primary outcome was percent of the day that the entire class was wearing their masks appropriately. Of the estimated almost 1000 students and 1048 classroom days reported, the mean percentage of the school day with appropriate mask usage was 76.9%. CONCLUSIONS: For a majority of the day while conducting in-person instruction, children in grades pre-K-2 are able to adhere to mask wearing as a key mitigation strategy for limiting SARS-CoV2 infection spread and possible future use.

QR Code Lecture Activity as a Tool for Increasing Nonmajors Biology Students' Enjoyment of Interaction with Their Local Environment.

The impact of the Internet on education has been recognized for decades, and as technology advances, the ways in which students can access Internet content is ever increasing. Most students have some kind of portable smart device with which they access Internet content without the locational constraints of a desktop computer. This mobility has prompted abundant literature suggesting ways that Quick Response Codes (QR codes), a kind of two dimensional barcode, could be used to advance student learning. However, very few studies have tested the usefulness of QR codes in undergraduate science classes. We report on our development of a campus "scavenger hunt" activity using QR codes. We found that this activity develops application skills of the concepts of native and invasive species and enjoyment of coverage of content relative to traditional lecture in a nonmajors Environmental Science class at a four-year teaching institution.

Folliculotropic Metastatic Melanoma: A Case Report and Review of the Literature.

Folliculotropic metastasis of cutaneous melanoma is rare, with only 5 published case reports in the English language literature since it was first described in 2009. We report a 41-year-old man with a primary cutaneous melanoma of the right upper preauricular region with metastatic spread to the parotid gland and pulmonary lymph nodes. Excision of the primary lesion was performed and immunotherapy was initiated. Sixteen months later, the patient presented with 2 new lesions of the left forehead and left neck. Histopathological examination was consistent with folliculotropic dermal deposits of metastatic melanoma. Deeper sectioning into the blocks revealed only sparse perifollicular pigment deposition and rare dermal melanocytes-a potential diagnostic pitfall had this been seen in the initial sections. This case represents the sixth and youngest patient to date with folliculotropic metastatic melanoma. This entity often presents in patients with advanced disease, including increased Breslow thickness and/or multiple metastases to lymph nodes, internal organs, or both. The folliculotropic metastases tend to be small and are often multiple. The precise relationship between folliculotropic primary melanoma and folliculotropic metastasis is unclear. In one reported case and in our patient, the primary tumor was noted to have a "folliculocentric" pattern. Because of the latter finding, the differential diagnosis includes multiple primary folliculotropic melanomas. Thus, clinical correlation and knowledge concerning the evolution of disease in the patient are critical. This case highlights a rare and unusual pattern of metastatic melanoma and potential problems in differential diagnosis.

Fontana-Masson stain in fungal infections.

BACKGROUND: Fontana-Masson (FM) staining is a histopathology technique used to identify dematiaceous fungi. The result often guides initial species identification and antifungal treatment; however, there is evidence that nondematiaceous fungi might react with this stain. Few studies in the current literature address this issue. OBJECTIVE: Our aim was to classify the FM staining patterns of common fungal pathogens for use by pathologists attempting to accurately identify fungi on histopathologic examination. METHODS: In total, 132 cases of culture proven mycoses were identified. We stained tissue with 2 different FM protocols and recorded the intensity and distribution of results. RESULTS: There was variability in staining, and many nondematiaceous fungi showed positivity, including Zygomycetes, Aspergillus, and Fusarium spp. LIMITATIONS: The study was limited by the number of cases. Of 132 cases identified, 112 cases had adequate tissue left after sectioning deeper into the block. CONCLUSION: Nondematiaceous fungi frequently stained positive with FM. The course of treatment should not be based on the result of this stain alone. Histopathology should be examined in multiple tissue sections, and therapy should be determined on the basis of clinical context and culture results.

Investigation of a cluster of Clostridium difficile infections in a pediatric oncology setting.

BACKGROUND: We investigated an increase in Clostridium difficile infection (CDI) among pediatric oncology patients. METHODS: CDI cases were defined as first C difficile positive stool tests between December 1, 2010, and September 6, 2012, in pediatric oncology patients receiving inpatient or outpatient care at a single hospital. A case-control study was performed to identify CDI risk factors, infection prevention and antimicrobial prescribing practices were assessed, and environmental sampling was conducted. Available isolates were strain-typed by pulsed-field gel electrophoresis. RESULTS: An increase in hospital-onset CDI cases was observed from June-August 2012. Independent risk factors for CDI included hospitalization in the bone marrow transplant ward and exposure to computerized tomography scanning or cefepime in the prior 12 weeks. Cefepime use increased beginning in late 2011, reflecting a practice change for patients with neutropenic fever. There were 13 distinct strain types among 22 available isolates. Hospital-onset CDI rates decreased to near-baseline levels with enhanced infection prevention measures, including environmental cleaning and prolonged contact isolation. CONCLUSION: C difficile strain diversity associated with a cluster of CDI among pediatric oncology patients suggests a need for greater understanding of modes and sources of transmission and strategies to reduce patient susceptibility to CDI. Further research is needed on the risk of CDI with cefepime and its use as primary empirical treatment for neutropenic fever.

High colonization rate and prolonged shedding of Clostridium difficile in pediatric oncology patients.

Surveillance testing for Clostridium difficile among pediatric oncology patients identified stool colonization in 29% of patients without gastrointestinal symptoms and in 55% of patients with prior C. difficile infection (CDI). A high prevalence of C. difficile colonization and diarrhea complicates the diagnosis of CDI in this population.

Immunohistochemical markers in fibrohistiocytic lesions: factor XIIIa, CD34, S-100 and p75.

BACKGROUND: The distinction between dermatofibroma (DF), dermatofibrosarcoma protuberans (DFSP), and other benign and malignant cutaneous spindle cell lesions frequently requires immunohistochemical staining. CD34 and factor XIIIa are the most commonly used immunostains; however, they may exhibit aberrant expression and introduce the potential for misdiagnosis. There is some data supporting that p75 and S100A6 may be additional helpful immunohistochemical markers. METHODS: We undertook a large case series examining the use of CD34 and factor XIIIa as well as p75 and S100A6 in DF, cellular DF, DFSP, indeterminate fibrohistiocytic lesion, and scar. RESULTS: As expected, CD34 stained DFSP, although it was usually negative in DF. Factor XIIIa was generally positive in DF and negative in DFSP. There were exceptions in both cases of DF and DFSP. S100A6 was routinely negative in all entities studied. P75 was negative in all cases except DFSP, approximately half of which showed weak and/or patchy positivity. CONCLUSIONS: We conclude that to date, CD34 and factor XIIIa remain the most reliable immunohistochemical markers for DF and DFSP.

Multicentric reticulohistiocytosis: a unique case with pulmonary fibrosis.

BACKGROUND: Multicentric reticulohistiocytosis (MRH) is a rare disease of uncertain etiology that most commonly presents as a papulonodular cutaneous eruption accompanied by erosive polyarthritis. Although MRH is considered a systemic disorder in that it targets skin and joints, involvement of thoracic and visceral organs is uncommon. OBSERVATIONS: A woman presented with diffuse cutaneous nodules, and skin biopsy findings revealed classic features of MRH. However, she also manifested severe pulmonary symptoms. A lung biopsy specimen showed prominent histiocytic infiltrates exhibiting the same characteristic morphologic features as those seen in her skin. Furthermore, the lung biopsy findings were significant for a pattern of usual interstitial pneumonia accompanied by notable lymphoid aggregates, a pattern of interstitial lung disease typical of systemic autoimmune and inflammatory conditions. CONCLUSIONS: These findings are notable because a histiocytic pulmonary infiltrate suggestive of direct pulmonary involvement by MRH is a rare event. In addition, presentation of MRH in the setting of usual interstitial pneumonia is unique. These observations document a new clinical and histopathologic presentation of MRH that is significant for expanding the idea of MRH as a systemic disease while supporting the notion that MRH is promoted by an inflammatory milieu.

Neurological altitude decompression sickness among U-2 pilots: 2002-2009.

INTRODUCTION: Compared to the previous 47 yr, U-2 pilots reported an increased number of altitude decompression sickness (DCS) incidents with central nervous system (CNS) manifestations during 2002-2009. Due to increasing incident severity during military operations, the U.S. Air Force initiated an investigation to prevent future mishaps. METHODS: We retrospectively examined all neurological DCS cases observed among U-2 pilots during 2002-2009. Urgency to prevent further pilot losses limited this study to using existing, often incomplete data sources. RESULTS: During 2002-2009, 16 confirmed incidents of CNS DCS occurred with 13 pilots, plus 4 possible incidents with 4 pilots. Significantly, 12 of 16 confirmed incidents occurred at 1 operating location, including 4 of 5 life-threatening cases. This series of cases were of a type and severity rarely found in flight operations and correlated temporally with increased sortie frequency/duration associated with combat operations. Multiple investigations confirmed no defects in aircraft, support equipment, or oxygen supplies. Nor were significant trends observed with age, habitus, environmental exposure, medication use, or cardiac defects. In 11 cases, symptom recognition occurred well after the 4-h point where clinical experience indicated risk should stabilize. Symptoms also recurred days later and responded to repeat hyperbaric oxygen therapy in three of four cases. Finally, neuropsychiatric symptoms persisted in six pilots for years and may represent permanent injury. CONCLUSIONS: An increase in U-2 CNS DCS cases probably resulted from more cockpit activity combined with longer, more frequent high-altitude exposures. Adjustments in preoxygenation, cabin altitude, exercise at altitude, and frequency of flights may reduce incidence.

Prophylactic correction of the international normalized ratio in neurosurgery: a brief review of a brief literature.

Prophylactic fresh-frozen plasma (FFP) transfusion is often undertaken in hemodynamically stable patients with a minimally elevated international normalized ratio (INR) prior to invasive procedures, despite little evidence in support of this practice. The authors review the current literature in an attempt to clarify best clinical practice with regard to this issue. Although the activated partial thromboplastin time and prothrombin time-INR are useful laboratory tests to measure specific clotting factors in the coagulation cascade, in the absence of active bleeding or a preexisting coagulopathy, their utility as predictors of overall bleeding risk is limited. Several studies have shown an imperfect correlation between mild elevations in the INR and subsequent bleeding tendency. Furthermore, FFP transfusion is not always sufficient to achieve normal INR values in patients who have mild elevations (< 2) to begin with. Finally, there are risks associated with FFP transfusion, including potential transfusion-associated [disease] exposures as well as the time delay imposed by laboratory testing and transfusion administration prior to initiation of procedures. The authors propose that the current concept of a "normal" INR value warrants redefinition to make it a more meaningful clinical tool. Based on their review of the literature, the authors suggest that in a hemodynamically stable patient population there is a range of mildly prolonged INR values for which FFP transfusion is not beneficial, and is potentially harmful.

Cutaneous metastatic cholangiocarcinoma: a report of three cases and review of the literature.

Cutaneous metastasis from cholangiocarcinoma is an extremely rare event. Herein, we present three cases with review of the literature. Case 1 is that of a young female with scalp metastasis. Cases 2 and 3 involve cutaneous metastasis to the sites of prior biliary drains, one occurring in a young female with a history of multiple biliary surgeries and one in a male with a history of sclerosing cholangitis. Review of the literature shows that the presentation of cutaneous metastases from cholangiocarcinoma can vary in terms of anatomic location and clinical features. The pathological and immunohistochemical profile of metastatic cholangiocarcinoma can be non-specific, and accurate diagnosis relies in part on clinical correlation. In summary, metastatic disease should always be included in the differential diagnosis of cutaneous lesions in patients with known malignancy.

A direct interaction between the RAG2 C terminus and the core histones is required for efficient V(D)J recombination.

V(D)J recombination is a tightly controlled process of somatic recombination whose regulation is mediated in part by chromatin structure. Here, we report that RAG2 binds directly to the core histone proteins. The interaction with histones is observed in developing lymphocytes and within the RAG1/RAG2 recombinase complex in a manner that is dependent on the RAG2 C terminus. Amino acids within the plant homeo domain (PHD)-like domain as well as a conserved acidic stretch of the RAG2 C terminus that is considered to be a linker region are important for this interaction. Point mutations that disrupt the RAG2-histone association inhibit the efficiency of the V(D)J recombination reaction at the endogenous immunoglobulin locus, with the most dramatic effect in the V to DJ(H) rearrangement.

The direct recruitment of BLNK to immunoglobulin alpha couples the B-cell antigen receptor to distal signaling pathways.

Following B-cell antigen receptor (BCR) ligation, the cytoplasmic domains of immunoglobulin alpha (Ig alpha) and Ig beta recruit Syk to initiate signaling cascades. The coupling of Syk to several distal substrates requires linker protein BLNK. However, the mechanism by which BLNK is recruited to the BCR is unknown. Using chimeric receptors with wild-type and mutant Ig alpha cytoplasmic tails we show that the non-immunoreceptor tyrosine-based activation motif (ITAM) tyrosines, Y176 and Y204, are required to activate BLNK-dependent pathways. Subsequent analysis demonstrated that BLNK bound directly to phospho-Y204 and that fusing BLNK to mutated Ig alpha reconstituted downstream signaling events. Moreover, ligation of the endogenous BCR induced Y204 phosphorylation and BLNK recruitment. These data demonstrate that the non-ITAM tyrosines of Ig alpha couple Syk activation to BLNK-dependent pathways.

Role of budesonide inhalation suspension in children with asthma.

OBJECTIVE: To evaluate the role of budesonide inhalation suspension (BIS) in the treatment of children with asthma. DATA SOURCES: Literature identified through Medline (1966-November 2000) and references obtained from selected articles. Search terms included budesonide and asthma. DATA SYNTHESIS: Asthma is a chronic inflammatory disease that affects approximately 4.8 million children in the US. By reducing inflammation, corticosteroids decrease symptoms and improve lung function. As the first nebulized corticosteroid, BIS offers an important treatment option for children with persistent asthma. CONCLUSIONS: BIS is effective in reducing symptoms and improving lung function in children with asthma. It should be used in children ages 1-8 years with moderate to severe persistent asthma who are unable to effectively use a metered-dose inhaler with or without a spacer or a dry-powder inhaler.

SHELL MICROSTRUCTURE OF GASTROPODS FROM LAKE TANGANYIKA, AFRICA: ADAPTATION, CONVERGENT EVOLUTION, AND ESCALATION.

Gastropod shells from Lake Tanganyika, with their heavy calcification, coarse noded ribbing, spines, apertural lip thickening and repair scars, resemble marine shells more closely than they resemble other lacustrine shells. This convergence between Tanganyikan and marine gastropod shells, however, is not just superficial. Scanning electron microscope (SEM) studies reveal that the Tanganyikan shells are primarily layers of crossed-lamellar crystal architecture (that is, needle-like aragonite crystals arranged into laths that are packed into sheets such that the aragonite needles of adjacent laths are never parallel). The number of crossed-lamellar layers can vary from one to four between different Tanganyikan gastropod species. In species with two or more crossed-lamellar layers, the orientation of the lamellae is offset by approximately 90° between the different layers. The number of crossed-lamellar layers in the shell wall is positively correlated with shell strength and with predation resistance. Three and four crossed-lamellar layers in the shell wall evolved several times independently within the endemic thiarid gastropod radiation in Lake Tanganyika. Repeated origins of three and four crossed-lamellar layers suggest that they may be specific adaptations by Tanganyikan gastropods to strengthen their shells as a defense against shell-crushing predators.

MORPHOLOGY AND BEHAVIOR OF CRABS AND GASTROPODS FROM LAKE TANGANYIKA, AFRICA: IMPLICATIONS FOR LACUSTRINE PREDATOR-PREY COEVOLUTION.

The shells of most lacustrine gastropods are typically small, weakly calcified, and modestly ornamented to unornamented. Similarly, most lacustrine crabs are usually small detritivores with weak chelae. A number of invertebrate taxa in Lake Tanganyika, however, deviate from these generalities. This study explores a predator-prey coevolution model as an explanation for the large, heavily calcified, and ornate gastropods and the robust, durophagous crabs of Lake Tanganyika. The endemic thiarid and viviparid gastropods from Lake Tanganyika have significantly thicker shells and higher frequencies of terminal apertural lip thickening than closely related cosmopolitan taxa from outside the lake. Tanganyikan gastropods also display considerably higher incidence of shell repair, following nonlethal shell damage, than cosmopolitan taxa of the same families. There is a strong positive correlation between gastropod apertural lip thickness and shell repair frequency among all the gastropod species analyzed. The endemic Tanganyikan potamonautid crab Platytelphusa armata (a molluscivore) possesses larger, more robust crushing chelae than other African potamonautid or potamonid crabs. In contrast with the cosmopolitan African crabs, the Tanganyikan crabs display molariform, rather than serrate dentition on their crushing chelipeds. In shell-crushing experiments, the Tanganyikan gastropod shells were an order of magnitude stronger than typical lacustrine gastropod shells, many well within the range of tropical marine gastropod shell strengths. Predation experiments with the endemic gastropods Spekia, Neothauma, Lavigeria spp., Paramelania spp. and the crab Platytelphusa armata showed that increased size, apertural lip thickness or shell sculpture reduced the successful predation rate of P. armata. Crabs with large chelae have a greater ratio of successful: unsuccessful attacks than crabs with small chelae. Among cases of successful predation, crabs with large chelae employed predation methods that required less time and energy (such as crushing the shell in the cheliped) than the methods employed by crabs with small chelae (such as peeling the shell from the aperture or the spire). The morphological, shell-crushing, and aquarium experiment data, considered in concert, provide strong support for the idea that the endemic gastropods and crabs of Lake Tanganyika have coevolved over the past 7 million years.

Diet and diabetes.

Present evidence suggests that the most important nutritional factor bearing on the risk of development of diabetes mellitus is an excessive caloric intake. Other evidence suggests that both dietary prevention of diabetes and mitigation of hyperglycemia by dietary means can prevent morbidity and mortality from the microvascular lesions of diabetes. Diet also has potential for reducing the extent of atherosclerotic lesions associated with the disease.