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1.
The expression of an X-linked defect in the CBA/N strain of mice has been found to result in a number of immune abnormalities. These include low responsiveness to antigens and a greatly reduced ability to respond to many of the common B cell mitogens. An in vitro manifestation of this condition is the virtual inability of CBA/N B cells to form colonies in lipopolysaccharide (LPS)-containing semisolid agar cultures. In this report we show evidence that the colony-forming ability of CBA/N spleen cells can be effectively restored by the bone marrow stromal-derived cell line S17. Spleen cells from 4-5-week-old homozygous CBA/N female mice were grown in double-layer agar cultures containing S17 feeder layers. Control cultures contained the fibroblast-like cell line 95.17 or were treated with medium alone. It was found that at an input cell concentration of 10(4) cells per plate, CBA/N colony formation was increased from a frequency of approximately 1 in 5,000 to 1 in 50 total splenic cells. Studies with purified surface immunoglobulin-positive cells indicate the direct involvement of S17 in this process. The CBA/N colonies formed were dependent on the presence of a mitogen (LPS) and secreted detectable amounts of IgM. Major implications of these findings and the application of this assay system to study the CBA/N defect have been discussed.  相似文献   
2.
Purpose:To analyze the reasons for delay in cataract surgery in patients with advanced cataracts during the COVID-19 pandemic.Methods:This was a prospective, cross-sectional, multicenter questionnaire study which included patients with mature cataract, nuclear sclerotic cataract grade IV, and cataracts with best corrected visual acuity (BCVA) <5/60, during the COVID-19 pandemic from December 2020 to April 2021. Reasons for delay in presentation to the hospital were analyzed.Results:One thousand four hundred seventy two patients were recruited with advanced cataracts. Absence of ophthalmic care nearby (44.2%), lack of awareness regarding elective surgeries (42.6%), lack of public transportation (37%), fear of contracting COVID-19 (23.4%), and waiting for outreach camps (20.4%) were found to be the reasons behind the delay in cataract surgery. 53.7% of the patients had worsening of defective vision and 55.3% of them had difficulty in carrying out activities of family living. 30.8% of the patients faced difficulty in commuting and 8.4% of the patients suffered a fall during this pandemic due to worsening of the visual acuity.Conclusion:The lockdown imposed during the pandemic has created a significant backlog of patients who are progressing to advanced cataracts due to lack of ophthalmic care nearby, lack of awareness regarding elective surgeries, lack of public transportation, and no outreach camps. Proactive measures to deal with this backlog are of utmost need to prevent blindness due to cataract.  相似文献   
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The emergence of smartphone-based imaging devices has been a boon in the field of ophthalmology, especially in obtaining high-quality ocular images. They can be specialized and utilized for imaging-specific regions of the eye. Among the multitude of applications of smartphone-based imaging, one of the upcoming major use is to image the microbiological world. Previous few reports have described attaching magnifying lenses of various types to the smartphone camera and transforming it into a microscope for imaging fungal hyphae and ocular surface parasites. We describe a novel technique of attaching the smartphone-based intraocular lens microscope (IOLSCOPE) to the slit lamp, thereby utilizing the slit lamp joystick for moving the smartphone over the concerned slide specimen to make it steady and obtain images of high resolution. This innovative do-it-yourself novel modification is especially useful in peripheral centers, vision centers, and local clinics for immediate screening and identification of microbial pathogens such as fungi and ocular surface parasites.  相似文献   
5.

Purpose

To report the safety and efficacy of simultaneous bilateral 25-gauge lens-sparing vitrectomy for vascularly active stage 4 retinopathy of prematurity (ROP).

Methods

Retrospective, noncomparative, consecutive case series. Twenty eyes of 10 babies who presented with vascularly active stage 4 ROP in both the eyes underwent simultaneous bilateral 25-gauge lens-sparing vitrectomy. After completing surgery for one eye, the other eye was re-prepped as performed before starting any new case of a different patient and an entire new set of disposable 25-gauge instruments were used. During the post-operative period parents were advised to keep separate eye drops for each eye and to wash their hands in between switching the eyes to put the drops.

Results

The mean follow-up was 8.7 months (range 4–17 months). None of the cases developed any signs of infection. The anatomic success rate for stage 4a was 100% (11/11 eyes) and for stage 4b was 8/9 eyes (89%).

Conclusion

These results show that simultaneous bilateral 25-gauge lens-sparing vitrectomy for stage 4 ROP is a safe and effective procedure with a good outcome provided both eyes of the baby are treated as eyes of two different patients.  相似文献   
6.
Aim: To report treatment outcomes of intra- and extraocular retinoblastomas seen at Aravind Eye Hospital, Coimbatore, South India.

Methods: Retrospective case series from January 2006 to December 2011 involving 106 babies. Clinical records were reviewed and data collected on presenting signs, gender, age, family history, ocular findings and treatment outcomes. All eyes were classified using the International Retinoblastoma Classification.

Results: The mean follow up was 35.4 months (range 1–75 months, SD 20.2, median 33 months). The mean age of presentation was 20.8 months (range 5 days to 120 months). There were 68 unilateral and 38 bilateral cases. Globe salvage rates were 100% for group A (11 eyes), B (16 eyes) and C (2 eyes). For group D, eye salvage rate was 29.5% (10/34 eyes). Survival rate of orbital retinoblastoma in our study was 55.5% (5/9 cases) at a mean follow up of 33.6 months. The overall patient survival rate was 89.6% with 11 deaths (10.4%). The commonest cause of death (7/11) was distant metastasis due to refusal to take initial treatment.

Conclusion: Greater improvement in patient survival can be achieved not only by early treatment of intraocular disease but also to convince patients to accept treatments including enucleation in this part of the world.  相似文献   

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Anemia frequently accompanies the diagnosis of acute lymphoblastic leukemia (ALL) in children and is considered to be one of the most common clinical complications of the disease. In addition, a low hemoglobin (Hb) level is often responsible for fatigue and other associated symptoms that cause a decline in the quality of life of these children. Traditionally, a number of contributing factors such as overcrowding of the marrow, coexisting infections, and nutritional deficits have been used to explain this phenomenon. However, recent advances in in vivo modeling and real-time ultrastructural analytical techniques have enabled researchers to examine leukemic bone marrow (BM) microenvironment more closely and helped to build mechanistic models of this process. Importantly, data from these studies show that in the majority of cases, the required stem cell populations and the erythropoietic growth mechanisms remain intact in leukemia. In this report, we aim to review the current state of knowledge regarding the cellular and molecular mechanisms implicated in the altered erythropoiesis at the time of diagnosis of leukemia. We propose that further understanding of the mechanisms of anemia in leukemia may help to manage some of its clinical consequences more effectively as well as to yield key insight into the process of leukemogenesis itself.  相似文献   
10.
We conducted a nested case-control study in a cohort of patients initiating antiretroviral therapy (ART) to identify risk factors and common manifestations of immune reconstitution inflammatory syndrome (IRIS) and to validate the Robertson criteria for IRIS prediction. HIV-infected patients at the Tuberculosis Research Centre clinics, Chennai and Madurai, India, initiating ART between July 2004 and June 2005 were prospectively studied. Of 97 patients (62% men, median age 32 years, median CD4 count 63 cells/μL) included, 34 developed IRIS. IRIS was more common in patients with a prior history of tuberculosis (74% versus 52%, P = 0.04), median time to development was 46 days and the sensitivity and specificity of the Robertson criteria to predict IRIS were 91% and 22%, respectively. In this population, IRIS was a common event, more so among patients with prior tuberculosis, and neither the rate of CD4 increase nor the Robertson criteria were useful in predicting its development.  相似文献   
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