Observations on phenomenological changes in Klebsiella Pneumoniae under fluidic stresses.

In the present work, experiments are conducted to understand the consequence of stresses generated by flowing fluid on the bacterial morphology and virulence in microfluidic channels. We consider Klebsiella pneumoniae (KP, a clinical isolate), an ESKAPE pathogen, to be the model bacteria responsible for blood stream infections, bacteremia, including pneumonia, urinary tract infections and more. Four different stress conditions are generated by changing the flow rate and channel geometry subsequently altering the shear rate and stressing time (τ). We observe significant changes in the structural aspects of the stressed bacteria. With an increase in stressing parameters, the viability of the bacterial sample deteriorated. Most importantly, these stressed samples proliferate much more than unstressed samples inside the RAW264.7 murine macrophages. The results shed light on the complex relationship between flow stresses and bacterial virulence. Furthermore, the bacterial samples are challenged with ciprofloxacin to see how they behave under different stress conditions. The observations presented in the present study can be extended to model deadly diseases including bacteremia using organ-on-a-chip technology and to understand bacterial pathogenicity under realistic environments.

Chronic Migraine May Be Associated With Postprandial Hypoglycemia in Adult Men: A Case Series.

Migraine is a common neurological disorder that significantly impacts patients around the world. In the United States, one in six individuals suffers from a migraine disorder. Despite its high prevalence, the etiology of migraine is not well understood. Multiple factors likely contribute to the development of both acute and chronic migraine, making the consensus as to the cause and treatment difficult. Presented here are three case studies involving adult males suffering from chronic migraine. Each subject provided a medical history and underwent physical, psychological, and neurological examinations. In addition, relevant bloodwork and cervical spine X-rays were obtained. Physical examination, laboratory studies, imaging, and psychological metrics were unremarkable with the notable exception of the three-hour oral glucose tolerance tests. All three patients displayed hypoglycemia at three hours. Furthermore, their symptoms markedly improved with the initiation of a ketogenic diet. These data are suggestive of a potential link between postprandial hypoglycemia and chronic migraine. Despite the small sample size, we feel that this report presents possible evidence for a connection between postprandial hypoglycemia and chronic migraine. Furthermore, properly controlled studies of larger sample sizes are required, but we suggest that clinicians consider screening patients for this easily overlooked metabolic disturbance, especially in the absence of other options.

Unilateral inferior altitudinal visual field defect related to COVID-19.

Ocular manifestations of COVID-19 are still being studied. Posterior segment involvement in viral entities is either direct viral involvement or a delayed immune response to the antigen. A 22-year-old woman presented with history of perceiving absolute inferior scotoma in the right eye for 4 days and history of fever and sore throat 10 days ago. Fundus examination revealed disc edema and vessel tortuosity. Humphreys Field Analyzer confirmed inferior field defect and Optical Coherence Tomography showed superior, nasal and inferior retinal nerve fiber layer thickening in the right eye. Patient was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse transcription polymerase chain reaction (RT-PCR) testing. Patient received three doses of injection methylprednisolone over 3 days. There was subjective resolution of scotoma reported 3 weeks posttreatment. We bring forward the first reported case of parainfectious optic neuritis associated with COVID-19.

Immunochromatographic assays for detection of Mycobacterium tuberculosis: what is the perfect time to test?

In this study, we aimed to correlate the analytical performance of SD BIOLINE TB Ag MPT64 Rapid Test kit (MPT64 assay) with the mycobacterial growth unit (GU) reported by the BACTEC MGIT 960 (MGIT 960) instrument. A total of 394 culture isolates reported positive by MGIT 960 were processed daily (until 'day 4') with the MPT64 assay until a positive MPT64 result was obtained and their GU values were noted daily before MPT64 testing. Based on this correlation of MPT64 positivity and corresponding GU values, a GU cut-off was determined. In the validation phase, with the experimentally determined GU cut-off value, 99.1% (576/581) of culture isolates were correctly identified as MTB within 2 days from instrument positivity. All results were available using a single-MPT64 assay strip, making the assay cost-effective. Thus, systematic implementation of the MPT64 assay proved to be cost-effective in a high-throughput laboratory without any delay in patient reporting.