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Objective. Relative biological effectiveness (RBE) differs between radiation qualities. However, an RBE of 1.0 has been established for photons regardless of the wide range of photon energies used clinically, the lack of reproducibility in radiobiological studies, and outdated reference energies used in the experimental literature. Moreover, due to intrinsic radiosensitivity, different cancer types have different responses to radiation. This study aimed to characterize the RBE of clinically relevant high and low photon energies in vitro for three human cancer cell lines: HCT116 (colon), HeLa (cervix), and PC3 (prostate). Approach. Experiments were conducted following dosimetry protocols provided by the American Association of Physicists in Medicine. Cells were irradiated with 6 MV x-rays, an 192 Ir brachytherapy source, 225 kVp and 50 kVp x-rays. Cell survival post-irradiation was assessed using the clonogenic assay. Survival fractions were fitted using the linear quadratic model, and survival curves were generated for RBE calculations. Main results. Cell killing was more efficient with decreasing photon energy. Using 225 kVp x-rays as the reference, the HCT116 RBE SF0.1 for 6 MV x-rays, 192 Ir, and 50 kVp x-rays were 0.89 ± 0.03, 0.95 ± 0.03, and 1.24 ± 0.04; the HeLa RBE SF0.1 were 0.95 ± 0.04, 0.97 ± 0.05, and 1.09 ± 0.03, and the PC3 RBE SF0.1 were 0.84 ± 0.01, 0.84 ± 0.01, and 1.13 ± 0.02, respectively. HeLa and PC3 cells had varying radiosensitivity when irradiated with 225 and 50 kVp x-rays. Significance. This difference supports the notion that RBE may not be 1.0 for all photons through experimental investigations that employed precise dosimetry. It highlights that different cancer types may not have identical responses to the same irradiation quality. Additionally, the RBE of clinically relevant photons was updated to the reference energy of 225 kVp x-rays., (Creative Commons Attribution license.)

We report a case of a 53-year-old HIV-negative patient in San Francisco, California, USA, with no classic mpox prodromal symptoms or skin lesions who experienced fulminant, vision-threatening scleritis, keratitis, and uveitis. Deep sequence analysis identified monkeypox virus RNA in the aqueous humor. We confirmed the virus on the cornea and sclera by PCR.

The 22q11.2 deletion syndrome is a multisystemic disorder characterized by a marked variability of phenotypic features, making the diagnosis challenging for clinicians. The wide spectrum of clinical manifestations includes congenital heart defects-most frequently conotruncal cardiac anomalies-thymic hypoplasia and predominating cellular immune deficiency, laryngeal developmental defects, midline anomalies with cleft palate and velar insufficiency, structural airway defects, facial dysmorphism, parathyroid and thyroid gland hormonal dysfunctions, speech delay, developmental delay, and neurocognitive and psychiatric disorders. Significant progress has been made in understanding the complex molecular genetic etiology of 22q11.2 deletion syndrome underpinning the heterogeneity of clinical manifestations. The deletion is caused by chromosomal rearrangements in meiosis and is mediated by non-allelic homologous recombination events between low copy repeats or segmental duplications in the 22q11.2 region. A range of genetic modifiers and environmental factors, as well as the impact of hemizygosity on the remaining allele, contribute to the intricate genotype-phenotype relationships. This comprehensive review has been aimed at highlighting the molecular genetic background of 22q11.2 deletion syndrome in correlation with a clinical multidisciplinary approach.

Objective: To review the virology, immunology, epidemiology, clinical manifestations, and treatment of the following 3 major zoonotic coronavirus epidemics: severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19)., Data Sources: Published literature obtained through PubMed database searches and reports from national and international public health agencies., Study Selections: Studies relevant to the basic science, epidemiology, clinical characteristics, and treatment of SARS, MERS, and COVID-19, with a focus on patients with asthma, allergy, and primary immunodeficiency., Results: Although SARS and MERS each caused less than a thousand deaths, COVID-19 has caused a worldwide pandemic with nearly 1 million deaths. Diagnosing COVID-19 relies on nucleic acid amplification tests, and infection has broad clinical manifestations that can affect almost every organ system. Asthma and atopy do not seem to predispose patients to COVID-19 infection, but their effects on COVID-19 clinical outcomes remain mixed and inconclusive. It is recommended that effective therapies, including inhaled corticosteroids and biologic therapy, be continued to maintain disease control. There are no reports of COVID-19 among patients with primary innate and T-cell deficiencies. The presentation of COVID-19 among patients with primary antibody deficiencies is variable, with some experiencing mild clinical courses, whereas others experiencing a fatal disease. The landscape of treatment for COVID-19 is rapidly evolving, with both antivirals and immunomodulators demonstrating efficacy., Conclusion: Further data are needed to better understand the role of asthma, allergy, and primary immunodeficiency on COVID-19 infection and outcomes., (Copyright © 2021. Published by Elsevier Inc.)

Purpose of Review: Modern advances in oncologic and end-organ therapies have led to an increase in immunocompromised patients and a corresponding rise in acute invasive fungal sinusitis (AIFS). Here, we present a comprehensive medical and surgical approach to the diagnosis and management of immunocompromised cancer and transplant patients with AIFS., Recent Findings: Aspergillus and Mucorales are the most common fungi to cause AIFS, though atypical fungal pathogens have been implicated particularly among patients on azole prophylaxis. Symptoms present in the majority of AIFS cases include fever, nasal congestion, and facial swelling. Nasal endoscopy and radiology are adjuncts to clinical exam with the gold standard diagnostic test still being histopathology, though molecular testing such as panfungal PCR is playing a larger role. The treatment of AIFS requires surgery, antifungal therapy, and reversal of immunosuppression. We recommend initiation of liposomal amphotericin B as an empiric therapy for AIFS, transitioned to targeted therapy when/if a fungal pathogen is identified. Goals of surgery include diagnostic sampling and debridement of necrotic tissue. Equally, if not more important, is reversal of underlying immune suppression. Immune-stimulating therapies hold promise for reducing mortality, but require additional study. Despite improvements in medical and surgical management of AIFS, mortality continues to approach 50%. Early diagnosis of this disease entity followed by aggressive surgical and medical management are important, including reversal of the underlying immunosuppression.

Importance: Pyoderma gangrenosum and necrotizing Sweet syndrome are diagnostically challenging variants of neutrophilic dermatosis that can clinically mimic the cutaneous and systemic features of necrotizing fasciitis. Improved characterization of these rare variants is needed, as improper diagnosis may lead to inappropriate or delayed treatment and the potential for morbidity., Objective: To determine the characteristics of necrotizing neutrophilic dermatosis to improve diagnostic accuracy and distinguish from infection., Design, Setting, and Participants: A case series of patients with necrotizing neutrophilic dermatosis treated at 3 academic hospitals (University of California San Francisco, Oregon Health and Science University, and University of Minnesota) from January 1, 2015, to December 31, 2017, was performed along with a literature review of related articles published between January 1, 1980, and December 31, 2017. Data were obtained from medical records as well as Medline and Embase databases. All patients had signs resembling necrotizing infection and had a final diagnosis of pyoderma gangrenosum with systemic features or necrotizing Sweet syndrome. Patients were excluded if a diagnosis other than neutrophilic dermatosis was made, if key clinical information was missing, and if reported in a non-English language., Main Outcomes and Measures: Description of key characteristics of necrotizing neutrophilic dermatosis., Results: Overall, 54 patients with necrotizing neutrophilic dermatosis were included, of which 40 had pyoderma gangrenosum with systemic features and 14 had necrotizing Sweet syndrome. Of the 54 patients, 29 (54%) were male and 25 (46%) were female, with a mean (SD) age of 51 (19) years. Skin lesions commonly occurred on the lower (19 [35%]) and upper (13 [24%]) extremities and developed after a surgical procedure (22 [41%]) or skin trauma (10 [19%]). Shock was reported in 14 patients (26%), and leukemoid reaction was seen in 15 patients (28%). Of the patients with necrotizing neutrophilic dermatosis, 51 (94%) were initially misdiagnosed as necrotizing fasciitis and subsequently received inappropriate treatment. Debridement was performed in 42 patients (78%), with a mean (SD) of 2 (2 [range, 1-12]) debridements per patient. Four amputations (7%) were performed. Forty-nine patients (91%) received antibiotics when necrotizing neutrophilic dermatosis was misdiagnosed as an infection, and 50 patients (93%) received systemic corticosteroids; all patients responded to immunosuppressants., Conclusions and Relevance: A complex spectrum of clinical findings of pyoderma gangrenosum and Sweet syndrome with prominent systemic inflammation exists that defines a new subset of neutrophilic dermatoses, termed necrotizing neutrophilic dermatoses; recognizing the difference between this variant and severe infection may prevent unnecessary surgical procedures and prolonged disease morbidity associated with a misdiagnosis and may expedite appropriate medical management.

Twenty years ago, the term "hospitalist" was coined at the University of California-San Francisco (San Francisco, CA), heralding a new specialty focused on the care of inpatients. There are now more than 50,000 hospitalists practicing in the United States. At many academic medical centers, hospitalists are largely replacing subspecialists as attendings on the inpatient medicine wards. At University of California-San Francisco, this has been accompanied by declining percentages of residency graduates who enter subspecialty training in internal medicine. The decline in subspecialty medicine interest can be attributed to many factors, including differences in compensation, decreased subspecialist exposure, and a changing research funding landscape. Although there has not been systematic documentation of this trend in pulmonary and critical care medicine, we have noted previously pulmonary and critical care-bound trainees switching to hospital medicine instead. With our broad, multiorgan system perspective, pulmonary and critical care faculty should embrace teaching general medicine. Residency programs have instituted creative solutions to encourage more internal medicine residents to pursue careers in subspecialty medicine. Some solutions include creating rotations that promote more contact with subspecialists and physician-scientists, creating clinician-educator tracks within fellowship programs, and appointing subspecialists to internal medicine residency leadership positions. We need more rigorous research to track the trends and implications of the generalist-specialist balance of inpatient ward teams on resident career choices, and learn what interventions affect those choices.

Interleukin-12 (IL-12) is a heterodimeric cytokine composed of p35 and p40 subunits and is required for induction of T helper 1 (Th1) responses. Knowledge of how the IL-12 gene is regulated will permit an understanding of susceptibility and resistance to pathogenic microbes and to autoiummune diseases. In this report, we provide the gene structures, nucleotide sequences and chromosomal assignment for the p35 and p40 subunits of mouse IL-12. The p35 and p40 subunit genes are distributed over 8 kb and 14 kb, and map to chromosomes 3 and 11, respectively. The p35 subunit gene consists of eight exons, including a 5'-noncoding exon that was defined by sequence comparison of genomic DNA with the 5'ends of novel cDNA molecules. Transcription of p35 mRNA can start from the first exon but can also initiate further downstream. Potential transcription regulatory elements, AP1, AP2, AP3, NF-kB and GATA recognition sequences, are located within 523 bp upstream of the p35 gene; however, no TATA box was identified. The p40 subunit gene consists of eight exons. A TATA box is located 30 bp upstream from the transcription start site, and AP1, AP3, GATA, and Pu.1 recognition sequences are located within 690 bp upstream of the p40 gene. An AGTTTCTACTTT sequence, which acts as an interferon-gamma response element in the promoter of the major histocompatibility complex class I gene, was also found upstream of the p40 gene.

A general strategy is described for the de novo design of proteins. In this strategy the sequence locations of hydrophobic and hydrophilic residues were specified explicitly, but the precise identities of the side chains were not constrained and varied extensively. This strategy was tested by constructing a large collection of synthetic genes whose protein products were designed to fold into four-helix bundle proteins. Each gene encoded a different amino acid sequence, but all sequences shared the same pattern of polar and nonpolar residues. Characterization of the expressed proteins indicated that most of the designed sequences folded into compact alpha-helical structures. Thus, a simple binary code of polar and nonpolar residues arranged in the appropriate order can drive polypeptide chains to collapse into globular alpha-helical folds.