Surgical management of oculomotor nerve palsy: a comparison of lateral rectus deactivation combined with either medial rectus resection or medial rectus fixation to the medial palpebral ligament

PURPOSE

To analyze and compare the outcome of two different surgical procedures in patients with complete oculomotor nerve palsy with large-angle exotropia.

METHODS

The medical records of patients with total oculomotor nerve palsy and large-angle exotropia operated on at a single center from January 2006 to June 2020 were reviewed retrospectively. One group underwent lateral rectus deactivation with medial rectus resection (resection group); the other group underwent lateral rectus deactivation with medial rectus fixation to the medial palpebral ligament (fixation group). Surgical outcomes on the first postoperative day and at 6 months postoperatively were analyzed, including alignment and postoperative complications. All statistical analyses were performed using STATA version 14. A P value of <0.05 was considered significant.

RESULTS

A total of 35 patients were included. There was a trend toward greater surgical success in the fixation group (93%) than in the resection group (65%), but these results were not statistically significant. Postoperative exotropic drifts were noted in both the procedures but tended to be more with patients in the resection group. Postoperative complications were noted only in the fixation group.

CONCLUSIONS

Lateral rectus deactivation with medial rectus fixation to the medial palpebral ligament requires more time and greater surgical expertise but appears to better prevent postoperative exotropic drift compared with lateral rectus deactivation combined with medial rectus resection.

Micro and nano plastics in food: A review on the strategies for identification, isolation, and mitigation through photocatalysis, and health risk assessment

Over the past few years, it has become increasingly evident that microplastic pollutant heavily contaminates water sources, posing a potential threat to both human and wildlife. These plastic pollutants do not get degraded efficiently by natural processes and the existing traditional treatment methods are incapable of fully eradicating them. In this regard, degradation of microplastic contaminants through photocatalytic methods has emerged as a powerful technique. Unfortunately, only a limited number of investigations have been reported in the field of photocatalytic degradation of microplastics. This comprehensive assessment focuses on the detailed analysis of the latest cutting edge engineered technologies aimed at efficiently separating, identifying microplastic contaminants present in food samples and degrading them through photocatalysis. Moreover, detailed information on various instrumental techniques that can be adopted to analyze the isolated micro sized plastic particles has been discussed. The assessment and degradation of these micro contaminants through photocatalytic methods is still in juvenile stage and there are lot of rooms to be explored. The need for profound contemplation on methods to degrade them through photocatalytic approaches as well as their possible health risks to humans motivated us to bring out this review.

Seasonal distribution of microplastics in surface waters of the Northern Indian Ocean

Seven expeditions were carried out during pre-monsoon, monsoon and post monsoon in 2018-2019 for marine plastic collection in surface waters of Northern Indian Ocean. PE and PP (83 %) is the dominant type of polymer found in the surface waters. Colored particles account for 67 % of all particles, with fibre/line accounting for 86 %. The average (Mean ± SD) microplastics concentration in the Northern Indian Ocean during pre-monsoon is 15,200 ± 7999 no./km², Monsoon is 18,223 ± 14,725 no./km² and post monsoon is 72,381 ± 77,692 no./km². BoB during pre-monsoon and post monsoon the microplastic concentration remains same except in the northern BoB this change is caused due to weak winds. Microplastics concentration varied both spatially, temporal and heterogeneity in nature. These differences are caused by effect of wind and seasonal reversal of currents. Microplastics collected in the anticyclonic eddy are 129,000 no./km².

Independent and combined impact of texture manipulation on oral processing behaviours among faster and slower eaters

Background: Food texture can moderate eating rate and ad libitum energy intake. Many foods are combined with condiments when consumed and the texture and eating properties differ considerably between condiments and carrier foods. Little is known about how combinations of textures impact oral processing or whether these differences are affected by individual eating-styles. Objective: We investigated the impact of texture parameters (unit size, thickness, hardness and lubrication) on oral processing behaviours for carrots and rice-crackers, and tested whether these behaviours differ between 'faster' and 'slower' eaters. Method: Seventy participants (34 males, 26.0 ± 5.4 years, BMI = 21.5 ± 1.7 kg m^-2) consumed 24 weight-matched carrot samples varying in unit size (large/medium/small), thickness (thick/thin), hardness (hard/soft) and lubrication (with/without mayonnaise). In a second step, participants consumed 8 weight-matched cracker samples varying in unit size (large/small), hardness (hard/soft) and lubrication (with/without mayonnaise). Sample consumption was video-recorded for post hoc behavioural annotation to derive specific oral processing behaviours. Participants were divided into 'faster' or 'slower' eater groups using a post hoc median split based on eating rate of raw carrot. Results: Across texture parameters, hardness had the largest influence (p < 0.001) on eating rate for both carrots and crackers. The independent texture differences for carrot ranked from most to least impact on eating rate was hardness > thickness > lubrication > unit size. For crackers, the rank order of eating rate was hardness > lubrication > unit size. Harder carrot samples with decreased unit size and reduced thickness combined had a larger synergistic effect in reducing eating rate (p < 0.001) than manipulation of any single texture parameter alone. Reducing the unit size of crackers while increasing hardness without lubrication combined (p = 0.015) to produce the largest reduction in eating rate. There were no significant differences between fast and slow eaters on their oral processing behaviours across texture manipulations. Conclusions: Combinations of texture manipulations have the largest impact in moderating oral processing behaviours, and this is consistent across 'faster' and 'slower' eaters. Changing food-texture presents an effective strategy to guide reformulation of product sensory properties to better regulate eating rate and energy intake, regardless of an individual's natural eating-style.

The impact of distance cataract surgical wet laboratory training on cataract surgical competency of ophthalmology residents

BACKGROUND

This study assessed the impact of distance cataract surgical wet laboratory training on surgical competency of ophthalmology residents at a tertiary-level ophthalmic training center in Trujillo, Peru.

METHODS

Three five-week distance wet lab courses were administered through Cybersight, Orbis International's telemedicine platform. Weekly lectures and demonstrations addressed specific steps in phacoemulsification surgery. Each lecture had two accompanying wet lab assignments, which residents completed and recorded in their institution's wet lab and uploaded to Cybersight for grading. Competency was assessed through anonymous grading of pre- and post-training surgical simulation videos, masked as to which occurred before and after training, using a standardized competency rubric adapted from the Ophthalmology Surgical Competency Assessment Rubric (OSCAR, scale of 0-32). Day one best-corrected post-operative visual acuity (BVCA) was assessed in the operative eye on the initial consecutive 4-6 surgeries conducted by the residents as per the norms of their residency training. An anonymous post-training satisfaction survey was administered to trainees'.

RESULTS

In total, 21 ophthalmic residents participated in the courses, submitting a total of 210 surgical videos. Trainees' average competency score increased 6.95 points (95%CI [4.28, 9.62], SD = 5.01, p < 0.0001, two sample t-test) from 19.3 (95%CI [17.2, 21.5], SD = 4.04) to 26.3 (95%CI [24.2, 28.3], SD = 3.93). Visual acuity for 92% of post-training resident surgeries (n = 100) was ≥20/60, meeting the World Health Organization's criterion for good quality.

CONCLUSIONS

Structured distance wet lab courses in phacoemulsification resulted in significantly improved cataract surgical skills. This model could be applicable to locations where there are obstacles to traditional in-person training, such as the current COVID-19 pandemic.

Retrospective analysis of visual outcomes in retropupillary iris-suture-fixated rigid intraocular lens in a tertiary eye center in southern India

PURPOSE

To report clinical outcomes of retropupillary iris-suture-fixated rigid intraocular lens (IFIOL) SETTING: Tertiary care ophthalmic hospital DESIGN: Retrospective study METHODS: This study included all eyes undergoing IFIOL with a minimum follow-up of 6 months between April 2017 and January 2019. Patients with preexisting anterior or posterior segment pathologies causing defective vision, uveitis or history of previous intraocular surgeries with exception of cataract surgery were excluded from the study. Data were retrieved from electronic medical records, and we documented demographics, history, position of cataractous lens or IOL, primary/secondary surgery and its complications. Postoperative visual acuity, pupillary response, diplopia, centration of IOL, inflammation were also recorded at the baseline visit and at 1 month, 3 months and 6 months postoperatively.

RESULTS

One hundred and ten eyes of 110 patients that underwent IFIOL were evaluated. Twenty-two patients (20%) underwent primary IFIOL, whereas 67 (60.9%) patients had secondary IFIOL. In 18 patients (16.36%), IFIOL was done to reposition decentered/dislocated IOLs. At the final follow-up, there was a significant improvement in corrected distance visual acuity (CDVA) with 87 patients (79.09%) achieving CDVA of 6/12 or better. IFIOL was stable and centered in 101 eyes (91.81%). Two patients (1.81%) had intraoperative complications. Postoperative iritis was seen in 7 patients (6.36%), and 4 patients (3.63%) had rise in IOP.

CONCLUSION

This is a safe, reliable, reproducible technique for aphakia rehabilitation and decentered IOL stabilization with good clinical outcome, especially in a limited resource setting.

A novel peptide pool with broad infectious antigen and MHC coverage for use as a positive stimulation control or as a means to elicit general T-cell responsiveness

T-cell activation assays such as Elispot or Intracellular Cytokine Staining (ICS) require appropriate positive stimulation controls. Compared with conventional assay controls based on polyclonal stimulation (e.g. PHA/Ionomycin), peptide pools have the advantage of providing a more physiological, TCR-mediated signal. A frequently used positive control is the so-called ‘CEF’ pool, containing 23 selected class-I-MHC-presented T-cell-stimulating peptides from CMV, EBV, and Influenza A. As a result of frequent and widespread exposure, most if not all individuals have T-cells specific for at least one of these agents. However, the ‘CEF pool’ only covers the most frequent HLA alleles in European-Caucasoids but not other ethnic groups where its usefulness is limited. We, therefore, designed an extended pool referred to as ‘CEFX pool’ with significantly improved coverage of both infectious agents and HLA-alleles (176 peptides), which also contains numerous CD4 T-cell-stimulating peptides. This novel pool provides a much stronger and more universal positive control than the ‘CEF’ pool and was successfully tested in various assay formats including Elispot, ICS, and ELISA of stimulated T-cell supernatants. For specific questions, sub-pools for CD4 or CD8 T-cell stimulation or not containing CMV-derived peptides are available. Because of its broad antigen coverage we are currently exploring the novel pool’s potential for measuring/monitoring general T-cell responsiveness in clinical situations such as immunodeficiency, immunosuppression, or immunosenescence.

Antemortem dental records versus individual identification

Background

Forensic odontology plays a pivotal role in the identification of victims in mass disasters utilizing "preserved dental records" or "ante-mortem records" available with the general dental practitioners. Identification of a deceased individual by comparing antemortem and postmortem records is more reliable and easier as compared to other methods. However, in India, the practice of maintaining dental case record requires additional emphasis.

Aim

The aim of the present study is to assess the knowledge, attitude, and practices of dental practitioners in South India regarding awareness and importance of maintaining patient's dental records.

Settings and Design

A descriptive questionnaire study was conducted among the alumni of the dental institution over a period of 3 months. The alumni who passed out from 2000 to 2015 were included in the study.

Materials and Methods

A structured questionnaire containing 24 questions regarding the knowledge, attitude, and practice of maintaining clinical case records was prepared and validated. Data were collected from 543 dental practitioners from various parts of South India who were the alumni of the dental institution.

Statistical Analysis

The data were summarized and analyzed using the statistical software Statistical Package for the Social Sciences. The descriptive analysis was done in percentages, and the results were tabulated.

Results

Overall, 58.39% of dentists were found to be maintaining records promptly, and 84.6% dentists have knowledge about forensic odontology, but only 8.4% of dentists have helped the government agencies during mass disasters.

Conclusion

This study reveals that the need of the hour is to change the attitude and to cultivate interest among practicing dentists regarding dental record maintenance which can tremendously help in the deceased individual identification process.

Characterization of human immunodeficiency virus Gag-specific gamma interferon-expressing cells following protective mucosal immunization with alphavirus replicon particles

A safe, replication-defective viral vector that can induce mucosal and systemic immune responses and confer protection against many infectious pathogens, such as human immunodeficiency virus type 1 (HIV-1), may be an ideal vaccine platform. Accordingly, we have generated and tested alphavirus replicon particles encoding HIV-1 Gag from Sindbis virus (SIN-Gag) and Venezuelan equine encephalitis virus (VEE-Gag), as well as chimeras between the two (VEE/SIN-Gag). Following intramuscular (i.m.), intranasal (i.n.), or intravaginal (IVAG) immunization with VEE/SIN-Gag and an IVAG challenge with vaccinia virus encoding HIV Gag (VV-Gag), a larger number of Gag-specific CD8+ intracellular gamma interferon-expressing cells (iIFNEC) were detected in iliac lymph nodes (ILN), which drain the vaginal/uterine mucosa (VUM), than were observed after immunizations with SIN-Gag. Moreover, a single i.n. or IVAG immunization with VEE/SIN-Gag induced a larger number of cells expressing HIV Gag in ILN, and immunizations with VEE/SIN-Gag through any route induced better protective responses than immunizations with SIN-Gag. In VUM, a larger percentage of iIFNEC expressed alpha4beta7 or alpha(Ebeta)7 integrin than expressed CD62L integrin. However, in spleens (SP), a larger percentage of iIFNEC expressed alpha4beta7 or CD62L than expressed alpha(Ebeta)7. Moreover, a larger percentage of iIFNEC expressed the chemokine receptor CCR5 in VUM and ILN than in SP. These results demonstrate a better induction of cellular and protective responses following immunizations with VEE/SIN-Gag than that following immunizations with SIN-Gag and also indicate a differential expression of homing and chemokine receptors on iIFNEC in mucosal effector and inductive sites versus systemic lymphoid tissues.

Synthesis of IL-13 by human B lymphocytes: Regulation and role in IgE production

BACKGROUND

Our laboratory has demonstrated previously that human tonsillar B lymphocytes express IL-13 mRNA OBJECTIVE: We sought to investigate IL-13 production by human B cells and the association between B cell-derived IL-13 and IgE secretion.

METHODS

Human B lymphocytes were isolated from tonsils and purified by means of rosetting with sheep RBCs or positive or negative selection with magnetic beads. They were stimulated with anti-CD40 antibodies with or without recombinant IL-4. Total mRNA was extracted, and IL-13 mRNA was measured by means of standard RT-PCR or by means of real-time PCR with commercially available primers. B cells were cultured with or without IL-13 neutralizing antibodies, and C epsilon transcripts and supernatant IgE levels were measured.

RESULTS

IL-13 mRNA was detected in human B lymphocytes stimulated with anti-CD40 antibodies and IL-4 or IL-2 but not in unstimulated B cells. Real-time PCR demonstrated a 10- to 15-fold increase in IL-13 mRNA, maximizing at 36 hours. IL-13 protein was detected from B lymphocytes on day 3 and accumulated through day 7. The synthesis of IL-13 required both CD40 and IL-4 stimulation. The presence of IL-13 was confirmed by means of intracellular staining of cultured B lymphocytes and antigen-stimulated nasal biopsy specimens from atopic individuals. Addition of IL-13 neutralizing antibodies to purified B-cell cultures inhibited IgE production by up to 80% and diminished IgE (C epsilon) transcripts by 50%.

CONCLUSION

Human B lymphocytes express IL-13 mRNA after ligation of CD40 and the addition of cytokines. Human B lymphocytes produce significant IL-13, and neutralization of IL-13 impairs IgE synthesis. IL-13 might be an important autocrine growth factor for IgE-producing B lymphocytes.

Maintenance of long-term immunological memory by low avidity IgM-secreting cells in bone marrow after mucosal immunizations with cholera toxin adjuvant

To understand the mechanisms involved in maintaining long-term immunological memory following mucosal immunizations, we determined the quality of serum hapten-specific immunoglobulins (Ig) and localized Ig-secreting cells (SC) of various isotypes in acute, persistent/resting memory and effector memory phases following oral versus intra-muscular (IM) immunizations. In the acute phase, both oral and IM immunizations induced high avidity Ig. However, in the persistent/resting memory phase, oral immunizations induced low avidity Ig while IM immunizations induced high avidity Ig. Following oral immunizations, in the persistent/resting memory phase, hapten-specific IgM titers in serum and IgM-SC in bone marrow (BM) dominated the immune response, suggesting an important role for IgM in the maintenance of memory.

Effect of a bcl-2 transgene on production and localization of precursor B cells in mouse bone marrow

Many B cell precursors die while differentiating in mouse bone marrow. To ascertain the mechanisms involved in this process, populations of B lineage cells and their tissue localization were analyzed in bone marrow of transgenic mice overexpressing the apoptosis inhibitor, Bcl-2. Immunofluorescence labeling and mitotic arrest were used to quantitate the number and proliferative activity of mu- pro-B cells (terminal deoxynucleotidyl transferase [TdT]+B220-, TdT+B220+, and TdT-B220+); pre-B cells (cmu+); and B cells (smu+). Mature B cells (IgM+IgD+) were increased 16- to 20-fold. In addition, immature B lymphocytes (IgM+IgD-/low), representing newly formed cells, were increased three- to sixfold, whereas pre-B cells and late pro-B cells were increased 30 to 60% in production rate. Earlier pro-B cells expressing TdT were unaffected. In spleen, both mature and immature B cells were greatly increased, but cells of precursor phenotype were few and TdT+ cells were absent. The in vivo location of B cells was examined by autoradiography using light and electron microscopy after intravenous injection of 125I-labeled antibodies. B lineage cells (B220+) were increased throughout bone marrow, often within dilated venous sinusoids, particularly in subosteal regions. Many intravascular and perisinusoidal cells were IgDhigh mature B lymphocytes. In contrast, many other IgM+ and IgDlow immature B lymphocytes clustered extravascularly around the central venous sinus. Plasma cells with distended endoplasmic reticulum were numerous. These findings provide evidence that, in addition to expanding the recirculating pool of B cells entering bone marrow from the blood stream, high levels of Bcl-2 can inhibit some of the apoptosis occurring during B cell differentiation, thereby expanding populations of B lymphopoietic precursor cells within the bone marrow parenchyma.

Apoptosis and macrophage-mediated cell deletion in the regulation of B lymphopoiesis in mouse bone marrow

Studies of cell population dynamics and microenvironmental organization of B lymphopoiesis in the bone marrow of normal mice and in various genetically modified states have shown that cell loss, involving processes of apoptosis and macrophage-mediated cell deletion, is a prominent feature of the primary genesis of B lymphocytes. Balanced against the influence of proliferative stimulants, the programmed death of precursor B cells provides a quantitative control, determining the magnitude of the final output of functional B lymphocytes to the peripheral immune system. The cell loss mechanisms can be readily set in motion by external or systemic influences, making the B-cell output particularly vulnerable to suppression by ionizing irradiation, stress or other systemic mediators. In addition, however, cell loss exerts an important quality control in the formation of the primary B-cell repertoire. The combination of apoptosis and macrophage-mediated deletion, acting at successive stages of B-cell differentiation, efficiently eliminates many precursors having non-productive Ig gene rearrangements, cell cycle dysregulations, and certain autoreactive Ig specificities. Outstanding areas of further work abound. Important questions concern the nature of mechanisms which underlie the processes of B-cell apoptosis and macrophage deletion in bone marrow, the microenvironmental signals involved in B-cell life or death decisions and genetic factors which may override these B-cell culling mechanisms. The answers will be relevant to problems of autoimmune disease, humoral immunodeficiency and B-cell neoplasia.