Clinical profile and response to steroids in post-fever retinitis: a nine-year experience from a referral institute in the rural hinterland of Central India

Purpose

To describe the demographics, clinical features, and treatment outcomes with systemic steroids in eyes presenting with post-fever retinitis (PFR) from Central India.

Methods

Single-center, retrospective analysis of 147 eyes of 98 PFR cases between 2011 and 2019.

Results

Mean age of the study cohort was 33.46?±?12.76 years, with 72 males and 26 females. The mean interval between the onset of fever and the diminution of vision was 21.10?±?13.54 days (range 0–60 days). The number of PFR cases increased over the nine years with 89 cases (90.1%) presenting during winters. Unilateral involvement was seen in 49 cases, while 49 had bilateral involvement. Clinical characteristics included: multifocal retinitis (n?=?122; 61.2%), hemorrhages (n?=?132; 89.8%), disc edema (n?=?57; 38.8%), anterior chamber reaction (n?=?28; 19%), and vitritis (n?=?103; 70.1%). Treatment included intravenous followed by oral steroids in 70 patients and oral steroids exclusively in 23; five patients denied treatment. The visual acuity improved from 1.09?±?0.52 LogMAR to 0.29?±?0.42 LogMAR (p?<?0.05).

Conclusion

There has been an increase in the prevalence of PFR cases over the last decade with clustering during the winters. Multifocal retinitis, retinal hemorrhages, and vitritis were the most common clinical findings in our series. The retinitis resolved with improvement in vision following steroid therapy in all eyes.

     

Electrochromic Os-based metallo-supramolecular polymers: electronic state tracking by in situ XAFS,IR, and impedance spectroscopies

In this study, the electronic states of Os-based metallo-supramolecular polymers (poly(OsL)²⁺) during electrochromism were tracked by in situ X-ray absorption fine structure (XAFS), infrared (IR), and impedance spectroscopies. The XAFS spectra suggested electronic charge migration in the polymer, and the in situ spectra revealed reversible changes caused by electrochemical redox reactions. The IR spectra of the polymers showed an IVCT band, and we also confirmed the reversible changes by applying a voltage to the redox cell. During the impedance measurements, we found a drastic decrease in the charge transfer resistance (R_CT) of the polymer films near the electrochemical redox potential.

In this study, the electronic states of Os-based metallo-supramolecular polymers (poly(OsL)²⁺) during electrochromism were tracked by in situ X-ray absorption fine structure (XAFS), infrared (IR), and impedance spectroscopies.     

(iii) Biomechanics of the knee and TKR

The principal aim of a total knee replacement (TKR) is to restore painless movements of the knee joint. Osteoarthritis, along with other pathologies that damage the articular surface of the knee, results in painful limitation of knee movement and alteration of shape and alignment of the joint. Restoration of the functional anatomy of the knee, including alignment, soft tissue balancing and restoration of the joint line, are integral to improving function. Factors that ensure long-term survival of the replaced knee have to be addressed while performing this procedure. Biomechanics of the knee and its restoration are key to improving both function and survival of a total knee replacement. Screw home movement in terminal extension and femoral roll back in flexion are unique to the knee joint. The patella improves extensor function by increasing its lever arm. Implant designs available include femoral components of fixed or multiple radii, high flexion knee replacements, posterior cruciate retaining or substituting designs and fixed or mobile tibial inserts. Computer navigation has been used to achieve accurate bone alignment and soft tissue balancing. Further research on these advances is essential to define their role in improving the results of TKR.     

Human monoclonal antibody AVP-21D9 to protective antigen reduces dissemination of the Bacillus anthracis Ames strain from the lungs in a rabbit model

Dutch-belted and New Zealand White rabbits were passively immunized with AVP-21D9, a human monoclonal antibody to protective antigen (PA), at the time of Bacillus anthracis spore challenge using either nasal instillation or aerosol challenge techniques. AVP-21D9 (10 mg/kg) completely protected both rabbit strains against lethal infection with Bacillus anthracis Ames spores, regardless of the inoculation method. Further, all but one of the passively immunized animals (23/24) were completely resistant to rechallenge with spores by either respiratory challenge method at 5 weeks after primary challenge. Analysis of the sera at 5 weeks after primary challenge showed that residual human anti-PA levels decreased by 85 to 95%, but low titers of rabbit-specific anti-PA titers were also measured. Both sources of anti-PA could have contributed to protection from rechallenge. In a subsequent study, bacteriological and histopathology analyses revealed that B. anthracis disseminated to the bloodstream in some na?ve animals as early as 24 h postchallenge and increased in frequency with time. AVP-21D9 significantly reduced the dissemination of the bacteria to the bloodstream and to various organs following infection. Examination of tissue sections from infected control animals, stained with hematoxylin-eosin and the Gram stain, showed edema and/or hemorrhage in the lungs and the presence of bacteria in mediastinal lymph nodes, with necrosis and inflammation. Tissue sections from infected rabbits dosed with AVP-21D9 appeared comparable to corresponding tissues from uninfected animals despite lethal challenge with B. anthracis Ames spores. Concomitant treatment with AVP-21D9 at the time of challenge conferred complete protection in the rabbit inhalation anthrax model. Early treatment increased the efficacy progressively and in a dose-dependent manner. Thus, AVP-21D9 could offer an adjunct or alternative clinical treatment regimen against inhalation anthrax.     

Temporal complexity and heterogeneity of single-neuron activity in premotor and motor cortex

The relationship between neural activity in motor cortex and movement is highly debated. Although many studies have examined the spatial tuning (e.g., for direction) of cortical responses, less attention has been paid to the temporal properties of individual neuron responses. We developed a novel task, employing two instructed speeds, that allows meaningful averaging of neural responses across reaches with nearly identical velocity profiles. Doing so preserves fine temporal structure and reveals considerable complexity and heterogeneity of response patterns in primary motor and premotor cortex. Tuning for direction was prominent, but the preferred direction was frequently inconstant with respect to time, instructed-speed, and/or reach distance. Response patterns were often temporally complex and multiphasic, and varied with direction and instructed speed in idiosyncratic ways. A wide variety of patterns was observed, and it was not uncommon for a neuron to exhibit a pattern shared by no other neuron in our dataset. Response patterns of individual neurons rarely, if ever, matched those of individual muscles. Indeed, the set of recorded responses spanned a much higher dimensional space than would be expected for a model in which neural responses relate to a moderate number of factors-dynamic, kinematic, or otherwise. Complex responses may provide a basis-set representing many parameters. Alternately, it may be necessary to discard the notion that responses exist to "represent" movement parameters. It has been argued that complex and heterogeneous responses are expected of a recurrent network that produces temporally patterned outputs, and the present results would seem to support this view.