Therapeutic hypothermia is now well established to improve neurodevelopmental outcomes after hypoxic-ischemic encephalopathy (HIE). Although the overall principles of treatment are now well established, many smaller questions are unclear. The potential impact of reversal of hypothermia therapy and the effect of high temperatures on recovery of the neurovascular unit after therapeutic hypothermia for HIE has received relatively little attention. This article will address the effects of hypoxia-ischemia and rewarming and increased temperatures on the neurovascular unit in preclinical and clinical models.

BACKGROUND: Criteria classifying fever of unknown origin (FUO) patients remains subject to discrepancies. A minimal standardized set of investigative tests serves as the foundation for the qualitative criteria, whereas quantitative incorporates the length of evaluation (7 or 3 days). A systematic review of studies would help physicians anticipate the frequency of illness types that could influence management.
METHODS: Prospective studies published in Medline (PubMed), Embase, Scopus, and Web of Science databases from January 1, 1997, to July 31, 2022, were included. A meta-analysis estimated associated pooled proportions between these criteria and diagnostic outcomes adjusted to the International Classification of Diseases, 10th edition (ICD-10) definitions.
RESULTS: Five qualitative studies corresponded to an increase of 15.3% (95% CI: 2.3-28.3%, p=0.021) in undiagnosed FUO proportions compared to eleven quantitative studies. Quantitative studies had 19.7% (95% CI: 6.0-33.4%, p=0.005) more in adjusted infectious disease proportions than qualitative studies. No significant differences in proportions between FUO defining criteria were noted for adjusted noninfectious inflammatory disorders (p=0.318), oncology (p=0.901), non-inflammatory miscellaneous disorders (p=0.321), diagnostic evaluation process, gross national income (GNI), or World Health Organization (WHO) geographic region.
CONCLUSIONS: Use of either qualitative or quantitative FUO criteria was associated with a statistically significant risk of over- or under-estimating infectious diseases and undiagnosed illnesses when using an ICD-10 adjusted FUO five-category system. Clinicians should anticipate differences depending on which criteria are used. While further research is warranted, qualitative criteria provide the best framework for study comparisons.

BACKGROUND: Fever of unknown origin (FUO) is a diagnostic challenge with highly heterogeneous causes. Its etiology can change according to the studied regions, and the chance of reaching a diagnosis depends on available resources. The aim of this study is to describe the clinical characteristics, etiology and the usefulness of diagnostic aids in cases of FUO managed over 12 years in a Colombian reference center.
METHODS: Single-institution retrospective case series. All cases of FUO between 2006 and 2017 were identified with the help of an electronic medical record search software. Cases of adults with fever for more than three weeks who remained undiagnosed after three days of hospitalization are described.
RESULTS: Of 1,009 cases evaluated, 112 cases met the inclusion criteria (median age 43 years, 66% men). The etiologies identified were infectious (31.2%), inflammatory (20.5%), neoplastic (14.3%), and miscellaneous (2.7%) diseases. 31.2% remained without etiological diagnosis. The most frequent conditions were tuberculosis (17%), Hodgkin\'s lymphoma (7.1%), systemic lupus erythematosus (6.3%), disseminated histoplasmosis, and adult Still\'s disease. Contrast tomography and biopsies were the studies that most frequently supported or confirmed the final diagnosis.
CONCLUSIONS: This series of contemporary Latin American cases suggests that the categories of FUO etiologies are similar to those reported in studies from developed countries, with tuberculosis being the most frequent cause in our setting. Our results highlight the importance of tomography-guided invasive studies in the diagnostic approach to FUO.

UNASSIGNED: Fever of unknown origin (FUO) and inflammation of unknown origin (IUO) are syndromes commonly used as medical diagnoses. Since the existing literature has a mixture of diagnostic approaches, developing consensus-based recommendations would be helpful for clinicians, researchers, and patients.
UNASSIGNED: A modified Delphi process was performed from October 2022 to July 2023, involving 4 rounds of online surveys and 2 live video conferences. The panel comprised international experts recruited based on peer-reviewed published publications and studies.
UNASSIGNED: Among 50 invited experts, 26 (52.0%) agreed to participate. Twenty-three panelists completed round 1 of the survey, 21 completed rounds 2 and 3, 20 completed round 4, and 7 participated in round 5 live video discussions. Of the participants, 18 (78.3%) were academic-based clinicians and researchers, 5 (21.7%) practiced in a community-based hospital, and 6 (26.1%) were female. Consensus was reached on 5 themes: (1) incorporating epidemiologic factors, such as geographic location and travel history; (2) updated criteria for classifying FUO or IUO; (3) initial evaluation approaches; (4) a classification system for diagnoses; and (5) recommendations for judicious limitation of empiric therapies. Experts strongly disagreed with using 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography/computed tomography as part of the diagnostic criteria for FUO. There were mixed opinions about the importance of the temperature measurement site, the 3-week minimum illness criterion, the need for a standard definition of relapsing fevers, and the use of similar evaluation strategies for FUO and IUO.
UNASSIGNED: These Delphi-generated consensus-based recommendations offer potential improvements compared with earlier definitions and a guide for clinical practice and future research.

BACKGROUND: The pea leafminer, Liriomyza huidobrensis, is one of the most important insect pests on vegetables and ornamentals. The survival and egg-laying behavior of leafminers are markedly affected by the environment temperature. However, the mechanisms underlying the relationship between egg-laying and temperature are still largely unknown.
RESULTS: Here, we find that leafminers have evolved an adaptive strategy to overcome the stress from high or low temperature by regulating oviposition-punching plasticity. We further show that this oviposition-punching plasticity is mediated by the expression of pyx in the ovipositor when subjected to disadvantageous temperature. Specifically, down-regulation of pyx expression in leafminers under low temperature stress led to a significant decrease in the swing numbers of ovipositor and puncture area of the egg spot, and consequently the lower amount of egg-laying compared to leafminers at ambient temperature. Conversely, activation of pyx expression under high temperature stress increased the swing numbers and puncture area, still resulting in a reduction of egg-laying amount.
CONCLUSIONS: Thereby, leafminers are able to coordinate pyx channel expression level and accordingly depress the oviposition. Our study uncovers a molecular mechanism underlying the adaptive strategy in insects that can avoid disadvantageous temperature for reproducing offspring. © 2024 Society of Chemical Industry.

Pyrexia of unknown origin (PUO) is a prolonged fever lasting several weeks without an identifiable cause despite extensive medical evaluation. Many a time, its cause remains largely unknown even after collecting a detailed medical history, conducting comprehensive physical assessments, and performing various standard laboratory tests and imaging procedures. This case series presents two cases of pyrexia of unknown origin. The first case includes a unique and uncommon presentation of non-Hodgkin\'s lymphoma. In the second case, the patient\'s fever remained unexplained after various investigations and treatments. The two documented cases of PUO presented in this report aim to contribute to the understanding of its diverse etiology and diagnostic challenges. By highlighting unique presentations and diagnostic dilemmas, the cases aim to promote awareness and facilitate timely recognition and appropriate management of PUO.

Fever of unknown origin (FUO) is a clinical conundrum for patients and clinicians alike, and imaging studies are often performed as part of the diagnostic workup of these patients. Recently, the Society of Nuclear Medicine and Molecular Imaging convened and approved a guideline on the use of nuclear medicine tools for FUO. The guidelines support the use of 2-18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in adults and children with FUO. 18F-FDG PET/CT allows detection and localization of foci of hypermetabolic lesions with high sensitivity because of the 18F-FDG uptake in glycolytically active cells that may represent inflammation, infection, or neoplasia. Clinicians should consider and insurers should cover 18F-FDG PET/CT when evaluating patients with FUO, particularly when other clinical clues and preliminary studies are unrevealing.

Connectomics research has made it more feasible to explore how neural circuits can generate multiple outputs. Female sexual drive provides a good model for understanding reversible, long-term functional changes in motivational circuits. After emerging, female flies avoid male courtship, but they become sexually receptive over 2 d. Mating causes females to reject further mating for several days. Here, we report that pC1 neurons, which process male courtship and regulate copulation behavior, exhibit increased CREB (cAMP response element binding protein) activity during sexual maturation and decreased CREB activity after mating. This increased CREB activity requires the neuropeptide Dh44 (Diuretic hormone 44) and its receptors. A subset of the pC1 neurons secretes Dh44, which stimulates CREB activity and increases expression of the TRP channel Pyrexia (Pyx) in more pC1 neurons. This, in turn, increases pC1 excitability and sexual drive. Mating suppresses pyx expression and pC1 excitability. Dh44 is orthologous to the conserved corticotrophin-releasing hormone family, suggesting similar roles in other species.

Antipyretics are one of the most frequently used agents in medicine. Numerous pharmacological agents, such as acetaminophen, non-steroidal anti-inflammatory agents (NSAIDs), salicylates, and selective cyclooxygenase 2 (COX-2) inhibitors, and nonpharmacological treatment modalities, such as tepid sponging and cooling blankets, are available for temperature reduction. There is a scarcity of definitive clinical guidelines on the choice of various agents in noncritically ill febrile patients. Our review examined the various modalities available for antipyresis and compared their safety and efficacy. The rationale for the choice of a particular pharmacological agent and route of administration were scrutinized. Our review also envisaged the perceived beneficial effects of antipyretics against the harmful side effects, including the evaluation of morbidity or mortality advantage conferred by antipyretics. The various toxicities associated with these agents were also highlighted.

Bone marrow examination (BME) is a useful tool in the diagnosis of haematological and non-haematological diseases. It plays an important role in early diagnosis of the underlying cause of pyrexia of unknown origin (PUO) and can influence the management of patients. Bone marrow aspiration (BMA) plays a very important role in establishing a definitive diagnosis in cases of PUO. The aim of this study was to review the indications and usefulness of bone marrow aspirates sent for microbiological evaluation as a diagnostic tool with histopathological correlation.
A prospective study was conducted from 1 January 2017 to 30 September 2019 in the Department of Microbiology and Pathology on the bone marrow aspirates of patients of all groups.
A total of 148 bone marrow aspirates were included. The cases were categorized as classical PUO (n = 81/148, 54.7%), nosocomial PUO (n = 4 /148, 2.7%), neutropenic PUO (n = 18/148, 12.1%), and immunocompromised PUO (n = 45/148, 30.4%), among which were systemic lupus erythematosus cases n = 8/45 (22.2%), human immunodeficiency virus positive cases n = 10/45 (17.7%), and renal transplant cases n = 27/45 (60%). A total of 28 BMAs were positive for microorganisms, out of which bacterial pathogens were n = 12 (42.8%), mycobacterial n = 12, 42.8%, fungal (n = 3, 10.7 %), and viruses (n = 1, 3.5%).
This study helped in highlighting the role of bone marrow examination as an important diagnostic method in the diagnosis of infectious diseases.