Evaluation of 3D tablet-based stereoacuity test ASTEROID in children with normal and abnormal visual acuity.

PURPOSE: To assess the utility of 3D, tablet-based, glasses-free Accurate STEReotest (ASTEROID) in children compared with the Titmus test. METHODS: Children aged 5-13 years were enrolled in a single-center, nonrandomized, observational comparison study and analyzed by age (5-7 vs 8-13 years) and visual acuity (20/25 or better in both eyes vs abnormal). Each participant underwent both the ASTEROID and Titmus stereoacuity tests. Stereoacuity was defined as fine (≤60 arcsec), moderate (61-200 arcsec), coarse (201-1199 arcsec), or very coarse to nil (≥1200 arcsec). Agreement between the tests was assessed using a weighted kappa (κ) statistic based on all four categories. RESULTS: A total of 112 children were included: 28 aged 5-7 with normal visual acuity, 30 aged 5-7 with abnormal visual acuity, 34 aged 8-13 with normal visual acuity, and 20 aged 8-13 with abnormal visual acuity. Mean ASTEROID score was 688 ± 533 arcsec (range, 13-1200 arcsec). Agreement between ASTEROID and Titmus test scores for participants overall was moderate (κ = 0.52). By subgroup, agreement was fair for children 5-7 with abnormal visual acuity (κ = 0.31), moderate for children 5-7 with normal visual acuity (κ = 0.47) and children 8-13 with normal visual acuity (κ = 0.42), and substantial for children 8-13 with abnormal visual acuity (κ = 0.76). Where ASTEROID and Titmus score group varied, ASTEROID score was poorer in 94% (47/50) of cases. CONCLUSIONS: ASTEROID is a digital, tablet-based test that evaluates global stereopsis, does not require glasses, and provides a continuum of scores. Among children, ASTEROID has good agreement with the Titmus test; however, it may be more sensitive at detecting stereovision deficits. Further study is necessary to determine which test is more accurate.

Systemic and ocular outcomes in patients with young-onset type 2 diabetes.

PURPOSE: To analyze the systemic and ocular outcomes in patients with young-onset type 2 diabetes (YO-DM2) based on grade of presenting diabetic retinopathy (DR). METHODS: Retrospective cohort study analysis of empaneled patients with type 2 diabetes <40 years old with retinopathy screening within the Los Angeles Department of Health Services between 01/01/2017-07/01/2021 were included. Patients were stratified based on presenting severity of DR determined on fundus photographs or clinical examination. Patient's systemic co-morbidities and ocular outcomes were then compared across each group. Procedural (e.g. intravitreal injections) and surgical interventions (e.g. pars plana vitrectomy) were documented as performed by the treating physician. RESULTS: 2795 patients were screened from 12,456 patients diagnosed with diabetes younger than age 40 (22.4 %). Of these, 1496 patients were diagnosed with type 2 DM. 1084 (72.4 %) of patients presented without DR, 307 (20.5 %) presented with non-proliferative diabetic retinopathy (NPDR), and 105 (7.0 %) of patients presented with proliferative diabetic retinopathy (PDR). Increasing presenting diabetic retinopathy severity was associated with longer duration of diabetes, greater systemic comorbidities (e.g. diabetic foot disease, neuropathy, chronic kidney or end stage renal disease), worse baseline and final visual acuity, and required more procedural and surgical interventions. CONCLUSIONS: Worse presenting DR severity in patients young-onset type 2 diabetes was associated with greater comorbid systemic and ocular disease with worse visual acuity outcomes. <1 % of patients without diabetic retinopathy or with mild NPDR were likely to progress to PDR. Diabetic kidney disease was an independent risk factor for developing neovascular glaucoma and retinal detachments. Prompt evaluation and intervention in patients with YO-DM2 may help reduce the associated systemic and ocular morbidity.

Nicotinamide for Skin-Cancer Chemoprevention in Transplant Recipients.

BACKGROUND: Immunosuppressed organ-transplant recipients have an increased incidence of, and mortality from, skin cancer. Nicotinamide (vitamin B3) enhances the repair of ultraviolet (UV) radiation-induced DNA damage, reduces the cutaneous immunosuppressive effects of UV radiation, and reduces the incidence of keratinocyte cancers (including squamous-cell and basal-cell carcinomas) and actinic keratoses among high-risk immunocompetent patients. Whether oral nicotinamide is useful for skin-cancer chemoprevention in organ-transplant recipients is unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, organ-transplant recipients who had had at least two keratinocyte cancers in the past 5 years to receive 500 mg of nicotinamide or placebo twice daily for 12 months. Participants were examined for skin lesions by dermatologists at 3-month intervals for 12 months. The primary end point was the number of new keratinocyte cancers during the 12-month intervention period. Secondary end points included the numbers of squamous-cell and basal-cell carcinomas during the 12-month intervention period, the number of actinic keratoses until 6 months after randomization, safety, and quality of life. RESULTS: A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group. The trial was stopped early owing to poor recruitment. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group (rate ratio, 1.0; 95% confidence interval, 0.8 to 1.3; P = 0.96). No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed. Adverse events and changes in blood or urine laboratory variables were similar in the two groups. CONCLUSIONS: In this 12-month, placebo-controlled trial, oral nicotinamide therapy did not lead to lower numbers of keratinocyte cancers or actinic keratoses in immunosuppressed solid-organ transplant recipients. (Funded by the National Health and Medical Research Council; ONTRANS Australian New Zealand Clinical Trials Registry number, ACTRN12617000599370.).

Fungal Infection After Descemet Membrane Endothelial Keratoplasty: Incidence and Outcomes.

PURPOSE: The aim of the study was to describe the incidence, presentation, management, and outcomes of fungal infection after Descemet membrane endothelial keratoplasty (DMEK). METHODS: Retrospective case series of culture-proven fungal infections after DMEK reported in the literature, directly by surgeons, and to the Eye Bank Association of America from January 1, 2011, to December 31, 2020. RESULTS: The domestic incidence of fungal infections, fungal keratitis, and fungal endophthalmitis after DMEK from 2011 to 2020 was 3.5, 1.3, and 2.2 per 10,000 cases, respectively, with no significant increasing trend. Thirty-four cases were identified, 14 (41.2%) published and 20 (58.8%) unpublished. Donor tissue fungal cultures were performed in 20 of the 34 (58.8%) cases and were positive in 19 of the 20 (95.0%), all but one Candida species. Recipient fungal cultures were performed in 29 of the 34 (85.3%) cases and were positive in 26 of the 29 (89.7%), all but one Candida species. Infection presented a mean of 33 ± 38 days (median 23, range 2-200, outlier 949) after transplantation: 25 (73.5%) with endophthalmitis and 9 (26.5%) with keratitis. Topical, intrastromal, intracameral, intravitreal, or systemic antifungal therapy was used in all 27 eyes with treatment data. Surgical intervention (DMEK explantation or partial removal, repeat endothelial keratoplasty, penetrating keratoplasty, and/or pars plana vitrectomy) was required in 21 of the 27 (77.8%) eyes. The corrected distance visual acuity at the last follow-up was ≥20/40 in 13 of the 27 (48.1%) eyes and counting fingers or worse in 6 of the 27 (22.2%) eyes. CONCLUSIONS: Fungal infection is a rare but serious complication of DMEK that results in counting fingers or worse corrected distance visual acuity in nearly a quarter of eyes.

Eyelid nystagmus in a child with cardiofaciocutaneous syndrome associated with BRAF mutation.

Eyelid nystagmus, thought to reflect midbrain or hindbrain disease, is a rare condition that typically occurs in association with neurologic and neuroophthalmic abnormalities. Cardiofaciocutaneous (CFC) syndrome associated with B-raf protooncogene serine/threonine kinase (BRAF) mutation is a complex syndrome that is associated with neurologic and neuroophthalmologic abnormalities. We report the case of a 4-year-old girl with CFC syndrome with global developmental delay who was referred for evaluation of alternating exotropia, right-sided dissociated vertical deviation, bilateral upgaze nystagmus, and bilateral eyelid fluttering. Neurological work-up revealed bilateral frontocentral sharp waves without seizure activity on electroencephalogram and mild left-sided cerebral volume loss on magnetic resonance imaging. To our knowledge, this is the first reported case of eyelid nystagmus in CFC syndrome. Eyelid nystagmus warrants neurological evaluation, because it is commonly associated with significant neurological abnormalities.

Isolation, Culture, and Genetic Engineering of Mammalian Primary Pigment Epithelial Cells for Non-Viral Gene Therapy.

Age-related macular degeneration (AMD) is the most frequent cause of blindness in patients >60 years, affecting ~30 million people worldwide. AMD is a multifactorial disease influenced by environmental and genetic factors, which lead to functional impairment of the retina due to retinal pigment epithelial (RPE) cell degeneration followed by photoreceptor degradation. An ideal treatment would include the transplantation of healthy RPE cells secreting neuroprotective factors to prevent RPE cell death and photoreceptor degeneration. Due to the functional and genetic similarities and the possibility of a less invasive biopsy, the transplantation of iris pigment epithelial (IPE) cells was proposed as a substitute for the degenerated RPE. Secretion of neuroprotective factors by a low number of subretinally-transplanted cells can be achieved by Sleeping Beauty (SB100X) transposon-mediated transfection with genes coding for the pigment epithelium-derived factor (PEDF) and/or the granulocyte macrophage-colony stimulating factor (GM-CSF). We established the isolation, culture, and SB100X-mediated transfection of RPE and IPE cells from various species including rodents, pigs, and cattle. Globes are explanted and the cornea and lens are removed to access the iris and the retina. Using a custom-made spatula, IPE cells are removed from the isolated iris. To harvest RPE cells, a trypsin incubation may be required, depending on the species. Then, using RPE-customized spatula, cells are suspended in medium. After seeding, cells are monitored twice per week and, after reaching confluence, transfected by electroporation. Gene integration, expression, protein secretion, and function were confirmed by qPCR, WB, ELISA, immunofluorescence, and functional assays. Depending on the species, 30,000-5 million (RPE) and 10,000-1.5 million (IPE) cells can be isolated per eye. Genetically modified cells show significant PEDF/GM-CSF overexpression with the capacity to reduce oxidative stress and offers a flexible system for ex vivo analyses and in vivo studies transferable to humans to develop ocular gene therapy approaches.

Morphological characteristics of early- versus late-onset macular edema in preterm infants.

Macular images of infants with early-onset edema (occurring at or before 33 weeks' postmenstrual age [PMA]) and infants with late-onset edema (at or after 36 weeks' PMA) were compared. At first appearance, early-onset edema has a more severe morphology, with foveal bulging and elongated cystoid spaces than late-onset edema, which presents as small cystoid spaces outside the foveal center. Morphological variations may be an indicator of the underlying cause of edema in preterm infants. The presence of mostly parafoveal small cystoid spaces in the late-onset edema group may be suggestive of an association with neurological injury.

Regression of Cystoid Macular Edema Three Weeks After Laser for Retinopathy of Prematurity.

Cystoid macular edema (CME) has been reported in the neonatal period associated with preterm birth; however, its pathogenesis remains unclear and is likely multifactorial. The authors report the case of a preterm infant imaged using optical coherence tomography (OCT), which revealed severe CME that regressed after laser treatment. Because laser for retinopathy of prematurity aims to reduce vascular endothelial growth factor (VEGF) levels, this case considers the possibility of VEGF-mediated CME pathogenesis. Further, the authors provide additional evidence of the value of OCT for noninvasive visualization of the preterm retina; the modality provides an effective way to evaluate and monitor progression of CME. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:472-475.].

Comparison of chorioretinal layers in rhesus macaques using spectral-domain optical coherence tomography and high-resolution histological sections.

Nonhuman primates are important preclinical models of retinal diseases because they uniquely possess a macula similar to humans. Ocular imaging technologies such as spectral-domain optical coherence tomography (SD-OCT) allow noninvasive, in vivo measurements of chorioretinal layers with near-histological resolution. However, the boundaries are based on differences in reflectivity, and detailed correlations with histological tissue layers have not been explored in rhesus macaques, which are widely used for biomedical research. Here, we compare the macular anatomy and thickness measurements of chorioretinal layers in rhesus macaque eyes using SD-OCT and high-resolution histological sections. Images were obtained from methylmethacrylate-embedded histological sections of 6 healthy adult rhesus macaques, and compared with SD-OCT images from 6 age-matched animals. Thicknesses of chorioretinal layers were measured across the central 3 mm macular region using custom semi-automated or manual software segmentation, and compared between the two modalities. We found that histological sections provide better distinction between the ganglion cell layer (GCL) and inner plexiform layer (IPL) than SD-OCT imaging. The first hyperreflective band between the external limiting membrane (ELM) and retinal pigment epithelium (RPE) appears wider on SD-OCT than the junction between photoreceptor inner and outer segments seen on histology. SD-OCT poorly distinguishes Henle nerve fibers from the outer nuclear layer (ONL), while histology correctly identifies these fibers as part of the outer plexiform layer (OPL). Overall, the GCL, inner nuclear layer (INL), and OPL are significantly thicker on histology, especially at the fovea; while the ONL, choriocapillaris (CC), and outer choroid (OC) are thicker on SD-OCT. Our results show that both SD-OCT and high-resolution histological sections allow reliable measurements of chorioretinal layers in rhesus macaques, with distinct advantages for different sublayers. These findings demonstrate the effects of tissue processing on chorioretinal anatomy, and provide normative values for chorioretinal thickness measurements on SD-OCT for future studies of disease models in these nonhuman primates.

HANDHELD SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IMAGING THROUGH THE UNDILATED PUPIL IN INFANTS BORN PRETERM OR WITH HYPOXIC INJURY OR HYDROCEPHALUS.

PURPOSE: The authors investigated feasibility of undilated handheld spectral domain optical coherence tomography (SDOCT) retinal imaging in preterm infants and children with neurologic abnormalities. METHODS: Under an institutional review board-approved protocol, the authors attempted handheld SDOCT imaging of the retina, choroid, and optic nerve in infants and young children without pupil dilation. Scans were analyzed for quality and successful capture of foveal, optic nerve, and retinal structural parameters and abnormalities. RESULTS: The authors obtained images through an undilated pupil of 11 infants/children over 28 eye imaging sessions, 27 at the bedside without sedation, and one under anesthesia. Infants had retinopathy of prematurity (n = 8), hypoxic ischemic encephalopathy (n = 2), or obstructive hydrocephalus (n = 1 child). Pupil sizes ranged from 1.0 mm to 3.5 mm. The authors captured fovea and optic nerve scans in 25/28 eye imaging sessions, with scans of adequate quality to discern prespecified foveal and optic nerve morphology, and of the 25 sessions, the choroidal-scleral junction was visible in all but 6 sessions. CONCLUSION: Undilated, handheld SDOCT imaging is a potential alternative method to evaluate the retina and optic nerve in patients with relative contraindication to pharmacological pupil dilation. This approach will enable the study of the eye-brain connection and ocular manifestations of neurologic diseases.

In Vivo Multimodal Imaging of Drusenoid Lesions in Rhesus Macaques.

Nonhuman primates are the only mammals to possess a true macula similar to humans, and spontaneously develop drusenoid lesions which are hallmarks of age-related macular degeneration (AMD). Prior studies demonstrated similarities between human and nonhuman primate drusen based on clinical appearance and histopathology. Here, we employed fundus photography, spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF), and infrared reflectance (IR) to characterize drusenoid lesions in aged rhesus macaques. Of 65 animals evaluated, we identified lesions in 20 animals (30.7%). Using the Age-Related Eye Disease Study 2 (AREDS2) grading system and multimodal imaging, we identified two distinct drusen phenotypes - 1) soft drusen that are larger and appear as hyperreflective deposits between the retinal pigment epithelium (RPE) and Bruch's membrane on SD-OCT, and 2) hard, punctate lesions that are smaller and undetectable on SD-OCT. Both exhibit variable FAF intensities and are poorly visualized on IR. Eyes with drusen exhibited a slightly thicker RPE compared with control eyes (+3.4 µm, P=0.012). Genetic polymorphisms associated with drusenoid lesions in rhesus monkeys in ARMS2 and HTRA1 were similar in frequency between the two phenotypes. These results refine our understanding of drusen development, and provide insight into the absence of advanced AMD in nonhuman primates.

Genomic Disruption of VEGF-A Expression in Human Retinal Pigment Epithelial Cells Using CRISPR-Cas9 Endonuclease.

PURPOSE: To employ type II clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 endonuclease to suppress ocular angiogenesis by genomic disruption of VEGF-A in human RPE cells. METHODS: CRISPR sequences targeting exon 1 of human VEGF-A were computationally identified based on predicted Cas9 on- and off-target probabilities. Single guide RNA (gRNA) cassettes with these target sequences were cloned into lentiviral vectors encoding the Streptococcuspyogenes Cas9 endonuclease (SpCas9) gene. The lentiviral vectors were used to infect ARPE-19 cells, a human RPE cell line. Frequency of insertion or deletion (indel) mutations was assessed by T7 endonuclease 1 mismatch detection assay; mRNA levels were assessed with quantitative real-time PCR; and VEGF-A protein levels were determined by ELISA. In vitro angiogenesis was measured using an endothelial cell tube formation assay. RESULTS: Five gRNAs targeting VEGF-A were selected based on the highest predicted on-target probabilities, lowest off-target probabilities, or combined average of both scores. Lentiviral delivery of the top-scoring gRNAs with SpCas9 resulted in indel formation in the VEGF-A gene at frequencies up to 37.0% ± 4.0% with corresponding decreases in secreted VEGF-A protein up to 41.2% ± 7.4% (P < 0.001), and reduction of endothelial tube formation up to 39.4% ± 9.8% (P = 0.02). No significant indel formation in the top three putative off-target sites tested was detected. CONCLUSIONS: The CRISPR-Cas9 endonuclease system may reduce VEGF-A secretion from human RPE cells and suppress angiogenesis, supporting the possibility of employing gene editing for antiangiogenesis therapy in ocular diseases.

The source of haemorrhage in traumatic basal subarachnoid haemorrhage.

Traumatic basal subarachnoid haemorrhage (TBSH) following trauma to the head, face or neck is well-established as a cause of death; however it remains a heavily disputed topic as the site of vascular injury is difficult to identify. Whilst many regions within the vasculature of the head and neck have been proposed as more susceptible to rupture, the vertebral artery remains the focal point of many investigations. We present a retrospective case review of TBSH in our forensic centre at Forensic and Scientific Services in Brisbane, Australia, from 2003 to 2011. Thirteen cases of TBSH were found, one case excluded due to vasculopathy. All decedents were male, the majority of which were involved in an altercation receiving blows to the head, face, or neck and were unconscious at the scene. All victims were under the influence of alcohol, drugs, or a combination thereof. External examination revealed injuries to the head, face, and neck in all cases. Various combinations of further examination techniques were used during the post-mortem examination including brain and/or cervical spine retention, CT imaging, and angiography. Vascular injury was identified in eight of the twelve cases, all of which occurred intracranially, with seven involving the vertebral artery. Histology was most reliable in identifying the rupture site and angiography failed to reveal a rupture site. The added benefits of histology over angiography are the ability to identify the microscopic architecture of the tear and to diagnose vasculopathy that may have rendered the individual more susceptible to TBSH.

Lower limb linear morphoea in a pregnant woman with known Graves' disease and cytomegalovirus immunoglobulin M positivity.

We report a case of linear morphoea in a 21-year-old woman with known Graves' disease who was also cytomegalovirus (CMV) IgM-positive and in her early first trimester of pregnancy. The histopathology showed hyalinisation of the dermis with perivascular superficial and deep lymphocytic infiltrates extending into the septae of the subcutis and impinging on adjacent lobules; there was also fibrosis of the subcutis. Magnetic resonance imaging showed T2 high intensity of the subcutaneous tissue and intermuscular planes of the thigh and leg. It is well known that morphoea can follow pregnancy and thyroid disease and that CMV is postulated to contribute in some patients. This case highlights a combination of risk factors for this disease that have not been reported collectively in the literature to our knowledge.

Post-mortem sperm retrieval in Australasia.

Post-mortem Sperm Retrieval (PMSR) is seldom requested in Australasia. The retrieval of sperm is permitted only by prior written consent or by order of the court. Sperm should be retrieved within 24 h following death; however, collection within 36 h may still be successful. The clinical response to such a request must be mindful of complex ethical and legal considerations. Clear, accessible and consistent law in this area would benefit medical, legal and societal stakeholders.

Antibiotics prior to embryo transfer in ART.

BACKGROUND: Embryo transfer (ET) involves the placement of one or more embryos into the uterine cavity, usually by passing a catheter through the cervical os. ET is the final step in an assisted reproductive technology (ART) cycle, where a woman has undergone controlled ovarian stimulation, egg retrieval and in vitro fertilisation of her eggs. Despite the transfer of high quality embryos, many ETs do not result in a pregnancy. There are many factors which may affect the success of ET, including the presence of upper genital tract microbial colonisation. The administration of antibiotics prior to ET has been suggested as an intervention to reduce levels of microbial colonisation and hence improve pregnancy rates. OBJECTIVES: To evaluate the effectiveness and safety of antibiotic administration prior to ET during ART cycles. SEARCH METHODS: We searched the Menstrual Disorders and Subfertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), The Cochrane Library, MEDLINE, Ovid MEDLINE® In-Process & Other Non-Indexed Citations, Ovid MEDLINE® Daily and Ovid MEDLINE® (from inception to February 2011), Ovid EMBASE (January 2010 to February 2011), Ovid PsycINFO, CINAHL, LILACS, trial registers for ongoing and registered trials, citation indexes, ClinicalStudyResults, PubMed, OpenSIGLE database and for for herbal and complimentary therapy protocols and reviews. SELECTION CRITERIA: Only randomised controlled trials were included. DATA COLLECTION AND ANALYSIS: The titles and abstracts of articles identified by the search were screened by one review author for eligibility. Two review authors then independently examined the full text articles for suitability for inclusion in the review. Data were extracted independently by two review authors. MAIN RESULTS: We identified four potential studies, of which three were excluded.The included trial reported clinical pregnancy rates but not live births. There was no evidence of a difference in clinical pregnancy rate between those receiving an amoxycillin and clavulanic acid antibiotic combination (64/178: 36%) and those not (61/172: 35.5%) (OR1.02, 95% CI 0.66 to 1.58). Genital tract colonisation was significantly reduced in women receiving this antibiotic regimen (OR 0.59, 95% CI 0.37 to 0.95). AUTHORS' CONCLUSIONS: This review suggests that the administration of amoxycillin and clavulanic acid prior to embryo transfer reduced upper genital tract microbial contamination but did not alter clinical pregnancy rates. The effect of this intervention on live birth is unknown. There are no data from randomised controlled trials to support or refute other antibiotic regimens in this setting.Future research is warranted to assess the efficacy of alternative antibiotic regimens. Researchers should assess live birth as the primary outcome and address quantitative microbial colonization as a secondary outcome.

Are they safe in there? - patient safety and trainees in the practice.

BACKGROUND: Due to the projected increase of medical graduates and general practice registrars, a rapid increase in new trainers and practices is required. The resulting mix of relatively inexperienced trainers and trainees makes the examination of the important question of patient safety even more pertinent. OBJECTIVE: To describe practical techniques that look beyond the door of the closed consulting room to detect unconscious incompetence in trainees. DISCUSSION: Trainees can both be conscious of their incompetence and ask for help, or unconscious of their incompetence. Many articles have been written on teaching trainees who ask for help, but it is the trainee who does not ask for help who may be at most risk of serious problems, and therefore compromise patient safety. Formative assessment and feedback should be used to empower trainees as self-regulated learners. There are seven principles of good feedback practice that help develop self-regulation. This article provides practical teaching tips for supervisors in general practice.

Osmoregulatory defect in adult mice associated with deficient prenatal expression of six2.

Suboptimal kidney development resulting from a genetic deficit in nephron number can have lifelong consequences that may lead to cardiorenal complications upon exposure to secondary insults in later life. To determine whether the inherited reduced renal reserve compromises the ability to handle osmotic stress in the adult animal, we challenged the heterozygous 3H1 Brachyrrhine (Br/+) mouse, which displays heritable renal hypoplasia associated with reduced embryonic six2 expression, to a solution of 2% NaCl for 5 days or to fluid restriction for 48 h. Blood chemistry, fluid intake, and physiological parameters, including renal measurements, were determined. Systemic hypertonicity by prolonged salt loading led to significant increases in plasma osmolality and plasma Na(+), along with polydipsia and polyuria, with a significant urine-concentrating defect that was resistant to DDAVP treatment in the adult Br/+ mouse compared with wild-type littermates. The Br/+ mouse also developed a significant increase in blood urea nitrogen at baseline that was further elevated when 2% NaCl was given. Fluid restriction for 48 h further enhanced plasma osmolality and plasma Na(+) responses, although the Br/+ mouse was evidently able to produce a small amount of concentrated urine at this time. Hypothalamic c-Fos expression was appropriately activated in the Br/+ mouse in response to both osmotic challenges, indicating an intact central neuroendocrine pathway that was not affected by the lack of congenital six2 expression. Collectively, our results demonstrate impaired osmoregulatory mechanisms consistent with chronic renal failure in the Br/+ mouse and indicate that six2 haploinsufficiency has a direct effect on postnatal fluid and electrolyte handling associated with fluid imbalance.

Miscarriage karyotype and its relationship with maternal body mass index, age, and mode of conception.

This study investigated the association between miscarriage karyotype and body mass index, maternal age, and mode of conception. Miscarriages after IVF and/or intracytoplasmic sperm injection were less frequently aneuploid; advanced maternal age was associated with an increase in aneuploid products of conception; overweight and obese women aged <35 years were less likely to have aneuploid miscarriages than women in a healthy weight range, suggesting alternate mechanisms for miscarriage in this population.

Tessellation analysis of glomerular spatial arrangement in mice with heritable renal hypoplasia.

Renal hypoplasia results from an insufficient kidney volume caused, in part, by a deficient number of glomeruli. The purpose of this study was to apply tessellation analysis to determine whether glomerular point patterns differed between adult normal (WT) and mutant (Br) mice with heritable renal hypoplasia and to delineate a spatial distribution accounting for the observed patterns. Kidneys from adult WT and Br mice were collected, processed with routine light histology and representative transverse sections were photographed. Cortical area and perimeter were calculated from traced tissue contours and glomeruli were identified and digitized. Voronoi tessellations were constructed and average parameters for Voronoi polygon number, area, perimeter and edge counts as well as spatial metrics comprising nearest neighbor and centroidal distances were calculated and compared. Point distributions were simulated by randomizing glomerular coordinates from each section and plotting the new points utilizing uniform random, Gaussian random, or isotropic functions. Average nearest neighbor distances were generated for each specimen and ranked with respect to corresponding values generated from 1,000 iterations for each simulated set. Results showed that WT and Br were significantly different for each parameter suggesting that WT kidneys possessed more glomeruli, but these were less clustered compared to Br. Simulations suggested that WT and Br demonstrated similar, but not identical, underlying glomerular spatial distributions. Defective gene expression in Br is important for determining glomerular number and the defective pattern likely results from a heterochronic disturbance consisting of a truncated growth trajectory during embryonic kidney development.