Prognostic values of serum lactate-to-bicarbonate ratio and lactate for predicting 28-day in-hospital mortality in children with dengue shock syndrome.

This study aimed to assess the clinical utility of blood lactate-to-bicarbonate (L/B) ratio, as a prognostic factor for 28-day in-hospital mortality in children with dengue shock syndrome (DSS), admitted to the pediatric intensive care unit (PICU). This single-center retrospective study was conducted at a tertiary children hospital in southern Vietnam from 2013 to mid-2022. Prognostic models for DSS mortality were developed, using a predefined set of covariates in the first 24 hours of PICU admission. Area under the curves (AUCs), multivariable logistic and Least Absolute Shrinkage and Selection Operator (LASSO) regressions, bootstrapping and calibration slope were performed. A total of 492 children with DSS and complete clinical and biomarker data were included in the analysis, and 26 (5.3%) patients died. The predictive values for DSS mortality, regarding lactate showing AUC 0.876 (95% CI, 0.807-0.944), and that of L/B ratio 0.867 (95% CI, 0.80-0.934) (P values of both biomarkers < .001). The optimal cutoff point of the L/B ratio was 0.25, while that of lactate was 4.2 mmol/L. The multivariable model showed significant clinical predictors of DSS fatality including severe bleeding, cumulative amount of fluid infused and vasoactive-inotropic score (>30) in the first 24 hours of PICU admission. Combined with the identified clinical predictors, the L/B ratio yielded higher prognostic values (odds ratio [OR] = 8.66, 95% confidence interval [CI], 1.96-38.3; P < .01) than the lactate-based model (OR = 1.35, 95% CI, 1.15-1.58; P < .001). Both the L/B and lactate models showed similarly good performances. Considering that the L/B ratio has a better prognostic value than the lactate model, it may be considered a potential prognostic biomarker in clinical use for predicting 28-day mortality in PICU-admitted children with DSS.

Phylogenetic and Recombination Analysis of Clinical Vitreous Humor-Derived Adenovirus Isolates Reveals Discordance Between Serotype and Phylogeny.

Purpose: To sequence, identify, and perform phylogenetic and recombination analysis on three clinical adenovirus samples taken from the vitreous humor at the Bascom Palmer Eye Institute. Methods: The PacBio Sequel II was used to sequence the genomes of the three clinical adenovirus isolates. To identify the isolates, a full genome-based multiple sequence alignment (MSA) of 722 mastadenoviruses was generated using multiple alignment using fast Fourier transform (MAFFT). MAFFT was also used to generate genome-based human adenovirus B (HAdV-B) MSAs, as well as HAdV-B fiber, hexon, and penton protein-based MSAs. To examine recombination within HAdV-B, RF-Net 2 and Bootscan software programs were used. Results: In the course of classifying three new atypical ocular adenovirus samples, taken from the vitreous humor, we found that all three isolates were HAdV-B species. The three Bascom Palmer HAdV-B genomes were then combined with over 300 HAdV-B genome sequences, including nine ocular HAdV-B genome sequences. Attempts to categorize the penton, hexon, and fiber serotypes using phylogeny of the three Bascom Palmer samples were inconclusive due to incongruence between serotype and phylogeny in the dataset. Recombination analysis using a subset of HAdV-B strains to generate a hybridization network detected recombination between nonhuman primate and human-derived strains, recombination between one HAdV-B strain and the HAdV-E outgroup, and limited recombination between the B1 and B2 clades. Conclusions: The discordance between serotype and phylogeny detected in this study suggests that the current classification system does not accurately describe the natural history and phylogenetic relationships among adenoviruses.

OUTCOMES OF INFECTIOUS PANUVEITIS ASSOCIATED WITH SIMULTANEOUS MULTI-POSITIVE OCULAR FLUID POLYMERASE CHAIN REACTION.

PURPOSE: To evaluate features of infectious panuveitis associated with multiple pathogens detected by ocular fluid sampling. METHODS: Single-center, retrospective, consecutive case series of patients with aqueous/vitreous polymerase chain reaction testing with >1 positive result in a single sample from 2001 to 2021. RESULTS: Of 1,588 polymerase chain reaction samples, 28 (1.76%) were positive for two pathogens. Most common pathogens were cytomegalovirus (n = 16, 57.1%) and Epstein-Barr virus (n = 13, 46.4%), followed by varicella zoster virus (n = 8, 28.6%), Toxoplasma gondii (n = 6, 21.4%), herpes simplex virus 2 (n = 6, 21.4%), herpes simplex virus 1 (n = 6, 21.4%), and Toxocara (n = 1, 3.6%). Mean initial and final visual acuity (logarithm of the minimum angle of resolution) were 1.3 ± 0.9 (Snellen ∼20/400) and 1.3 ± 1.1 (Snellen ∼20/400), respectively. Cytomegalovirus-positive eyes (n = 16, 61.5%) had a mean final visual acuity of 0.94 ± 1.1 (Snellen ∼20/175), whereas cytomegalovirus-negative eyes (n = 10, 38%) had a final visual acuity of 1.82 ± 1.0 (Snellen ∼20/1,320) ( P < 0.05). Main clinical features included intraocular inflammation (100%), retinal whitening (84.6%), immunosuppression (65.4%), retinal hemorrhage (38.5%), and retinal detachment (34.6%). CONCLUSION: Cytomegalovirus or Epstein-Barr virus were common unique pathogens identified in multi-PCR-positive samples. Most patients with co-infection were immunosuppressed with a high rate of retinal detachment and poor final visual acuity. Cytomegalovirus-positive eyes had better visual outcomes compared with cytomegalovirus-negative eyes.

Newly detected paediatric melioidosis cases in a single referral children's hospital in Ho Chi Minh City indicate the probable underrecognition of melioidosis in South Vietnam.

BACKGROUND: The epidemiology of melioidosis in Vietnam, a disease caused by the soil bacterium Burkholderia pseudomallei, remains unclear. This study aimed to detect paediatric melioidosis in South Vietnam and describe clinical features and the geographic distribution. METHODS: We introduced a simple laboratory algorithm for detecting B. pseudomallei from clinical samples at Children's Hospital 2 in Ho Chi Minh City in July 2015. A retrospective observational study of children <16 y of age with culture-confirmed melioidosis between July 2015 and August 2019 was undertaken. RESULTS: Thirty-five paediatric cases of melioidosis were detected, with cases originating from 13 of 32 provinces and cities in South Vietnam. The number of paediatric melioidosis cases detected from a certain region correlated with the overall number of inpatients originating from the respective geographic area. Suppurative parotitis (n=15 [42.8%]) was the most common clinical presentation, followed by lung infection (n=10 [28.6%]) and septicaemia (n=7 [20%]). Fourteen (40%) children had disseminated disease, including all cases of lung infection, four cases with central nervous system symptoms and four (11.4%) deaths. CONCLUSIONS: The patients' origin indicates a wide distribution of melioidosis in South Vietnam. It seems probable that cases not only in children, but also in adults, remain grossly undiagnosed. Further awareness raising and laboratory capacity strengthening are needed in this part of the country.

Unexplained Vision Loss Associated With Intraocular Silicone Oil Tamponade in Rhegmatogenous Retinal Detachment Repair.

Purpose: To evaluate the visual outcomes with unexplained vision loss during or after silicone oil (SO) tamponade. Methods: This multicenter retrospective case series comprised patients with unexplained vision loss associated with SO tamponade or its removal. Eyes with other clear secondary identifiable causes of vision loss were excluded. Results: Twenty-nine eyes of 28 patients (64% male) were identified. The mean age was 50 ± 13 years (range, 13-78 years). The mean duration of SO tamponade was 148 ± 38 days. Eighteen eyes (62%) developed unexplained vision loss while under SO; 11 (38%) had vision loss after SO removal. The most common optical coherence tomography (OCT) finding was ganglion cell layer (GCL) thinning (55%). Eyes with vision loss after SO removal had a mean logMAR best-corrected visual acuity (BCVA) of 0.6 ± 0.7 (Snellen 20/85) before SO tamponade and 1.2 ± 0.4 (20/340) before SO removal. By the last follow-up after SO removal, the BCVA had improved to 1.1 ± 0.4 (20/235). In eyes with vision loss after SO removal, the BCVA before SO removal was 0.7 ± 0.7 (20/104), which deteriorated to 1.4 ± 0.4 (20/458) 1 month after SO removal. By the last follow-up, the BCVA had improved to 1.0 ± 0.5 (20/219). Conclusions: Unexplained vision loss can occur during SO tamponade or after SO removal. Vision loss was associated with 1000-centistoke and 5000-centistoke oil and occurred in macula-off and macula-on retinal detachments. The duration of tamponade was 3 months or longer in the majority of eyes. Most eyes had GCL thinning on OCT. Gradual visual recovery can occur yet is often incomplete.

Phylogenetic and Genomic Characterization of Whole Genome Sequences of Ocular Herpes Simplex Virus Type 1 Isolates Identifies Possible Virulence Determinants in Humans.

Purpose: There are limited data on the prevalence and genetic diversity of herpes simplex virus type 1 (HSV-1) virulence genes in ocular isolates. Here, we sequenced 36 HSV-1 ocular isolates, collected by the Bascom Palmer Eye Institute, a university-based eye hospital, from three different ocular anatomical sites (conjunctiva, cornea, and eyelid) and carried out a genomic and phylogenetic analyses. Methods: The PacBio Sequel II long read platform was used for genome sequencing. Phylogenetic analysis and genomic analysis were performed to help better understand genetic variability among common virulence genes in ocular herpetic disease. Results: A phylogenetic network generated using the genome sequences of the 36 Bascom Palmer ocular isolates, plus 174 additional strains showed that ocular isolates do not group together phylogenetically. Analysis of the thymidine kinase and DNA polymerase protein sequences from the Bascom Palmer isolates showed multiple novel single nucleotide polymorphisms, but only one, BP-K14 encoded a known thymidine kinase acyclovir resistance mutation. An analysis of the multiple sequence alignment comprising the 51 total ocular isolates versus 159 nonocular strains detected several possible single nucleotide polymorphisms in HSV-1 genes that were found significantly more often in the ocular isolates. These genes included UL6, gM, VP19c, VHS, gC, VP11/12, and gG. Conclusions: There does not seem to be a specific genetic feature of viruses causing ocular infection. The identification of novel and common recurrent polymorphisms may help to understand the drivers of herpetic pathogenicity and specific factors that may influence the virulence of ocular disease.

INTRAOCULAR INFLAMMATION INCIDENCE AFTER INTRAVITREAL BROLUCIZUMAB INJECTION FOR EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

PURPOSE: We evaluated the clinical outcomes of intraocular inflammation (IOI) of eyes with neovascular age-related macular degeneration (AMD) injected with brolucizumab in our tertiary referral center. METHODS: A retrospective case series for which clinical records of all eyes that received intravitreal brolucizumab at Bascom Palmer Eye Institute between December 1, 2019, and April 1, 2021, were reviewed. RESULTS: There were 345 eyes of 278 patients who received 801 brolucizumab injections. IOI was detected in 16 eyes of 13 patients (4.6%). In those patients, baseline Logarithm of Minimu Angle of Resolution (logMAR) best-corrected visual acuity was 0.32 0.2 (20/42), while it was 0.58 0.3 (20/76) at IOI presentation. The mean number of injections among eyes experiencing IOI was 2.4, and the interval between the last brolucizumab injection and IOI presentation was 20 days. There was no known case of retinal vasculitis. Management of IOI included topical steroids in seven eyes (54%), topical and systemic steroids in five eyes (38%), and observation in one eye (8%). Best-corrected visual acuity returned to baseline and inflammation resolved in all eyes by the last follow-up examination. CONCLUSION: Intraocular inflammation after brolucizumab injection for neovascular AMD was not uncommon. Inflammation resolved in all eyes by the last follow-up visit.

Early diagnostic indicators of dengue versus other febrile illnesses in Asia and Latin America (IDAMS study): a multicentre, prospective, observational study.

BACKGROUND: Improvements in the early diagnosis of dengue are urgently needed, especially in resource-limited settings where the distinction between dengue and other febrile illnesses is crucial for patient management. METHODS: In this prospective, observational study (IDAMS), we included patients aged 5 years and older with undifferentiated fever at presentation from 26 outpatient facilities in eight countries (Bangladesh, Brazil, Cambodia, El Salvador, Indonesia, Malaysia, Venezuela, and Viet Nam). We used multivariable logistic regression to investigate the association between clinical symptoms and laboratory tests with dengue versus other febrile illnesses between day 2 and day 5 after onset of fever (ie, illness days). We built a set of candidate regression models including clinical and laboratory variables to reflect the need of a comprehensive versus parsimonious approach. We assessed performance of these models via standard measures of diagnostic values. FINDINGS: Between Oct 18, 2011, and Aug 4, 2016, we recruited 7428 patients, of whom 2694 (36%) were diagnosed with laboratory-confirmed dengue and 2495 (34%) with (non-dengue) other febrile illnesses and met inclusion criteria, and were included in the analysis. 2703 (52%) of 5189 included patients were younger than 15 years, 2486 (48%) were aged 15 years or older, 2179 (42%) were female and 3010 (58%) were male. Platelet count, white blood cell count, and the change in these variables from the previous day of illness had a strong association with dengue. Cough and rhinitis had strong associations with other febrile illnesses, whereas bleeding, anorexia, and skin flush were generally associated with dengue. Model performance increased between day 2 and 5 of illness. The comprehensive model (18 clinical and laboratory predictors) had sensitivities of 0·80 to 0·87 and specificities of 0·80 to 0·91, whereas the parsimonious model (eight clinical and laboratory predictors) had sensitivities of 0·80 to 0·88 and specificities of 0·81 to 0·89. A model that includes laboratory markers that are easy to measure (eg, platelet count or white blood cell count) outperformed the models based on clinical variables only. INTERPRETATION: Our results confirm the important role of platelet and white blood cell counts in diagnosing dengue, and the importance of serial measurements over subsequent days. We successfully quantified the performance of clinical and laboratory markers covering the early period of dengue. Resulting algorithms performed better than published schemes for distinction of dengue from other febrile illnesses, and take into account the dynamic changes over time. Our results provide crucial information needed for the update of guidelines, including the Integrated Management of Childhood Illness handbook. FUNDING: EU's Seventh Framework Programme. TRANSLATIONS: For the Bangla, Bahasa Indonesia, Portuguese, Khmer, Spanish and Vietnamese translations of the abstract see Supplementary Materials section.

Haptic Erosion Following Sutureless Scleral-fixated Intraocular Lens Placement.

PURPOSE: To describe the clinical features and visual outcomes of eyes with conjunctival haptic erosion after sutureless intrascleral (SIS) fixated intraocular lens (IOL) placement. DESIGN: Retrospective case series. SUBJECTS: Patients experiencing haptic erosion after SIS fixation between January 1, 2013, and March 1, 2022. METHODS: A multicenter, multisurgeon, retrospective review. MAIN OUTCOME MEASURES: Clinical features, visual outcomes, and treatment options following haptic erosions after SIS fixation. RESULTS: Nineteen eyes with haptic erosion were identified. The mean age at initial SIS fixation was 64 ± 12 years (range, 38-81 years). There were 5 (26%) eyes with a history of conjunctiva involving ocular surgery, including scleral buckle surgery and tube shunt surgery. Trocar-assisted fixation was performed in 15 (79%) eyes, whereas needle fixation was used in 4 (21%) eyes. Eighteen (95%) sets of haptics were flanged with a low temperature cautery. Seventeen (90%) sets of haptics were externalized superiorly and inferiorly, and 2 (10%) sets of haptics were externalized nasally and temporally. Haptics were covered by conjunctiva in 14 (74%) eyes and by scleral flap in 5 (26%) eyes. All patients experienced a single haptic erosion, of which 8 (43%) were located superiorly, 9 (47%) inferiorly, and 2 (10%) temporally. The mean interval between the initial SIS fixation and haptic erosion was 278 ± 437 days. After correction of the erosion, 18 (95%) eyes had a stable IOL at the last follow-up, with no recurrence of haptic erosion. In this series, there were no cases of endophthalmitis. CONCLUSIONS: Haptic erosion is a notable complication after SIS fixated IOL surgery but may be repaired with favorable visual outcomes. Careful evaluation of the conjunctiva should be considered before the surgery. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Morning glory disc anomaly associated with moyamoya disease and pituitary stalk duplication.

Purpose: We report a case of a 10-year-old with Moring glory disc anomaly (MGDA) associated with Moyamoya disease and pituitary stalk duplication. Observations: A 10-year-old Asian child presented with decreased vision in the right eye and bilateral nystagmus. Both dilated fundus exam and magnetic resonance imaging (MRI) of the orbit confirmed MGDA of the right eye. MRI of the brain demonstrated duplication of the pituitary stalk. Magnetic resonance angiography (MRA) of the brain revealed bilateral severe narrowing (greater on the right side) of the distal supraclinoid internal carotid arteries with bilateral reconstitution at the carotid terminus and prominent collaterals, suggestive of Moyamoya disease. Conclusions: Patients with MGDA should undergo neuroimaging due to the associated central nervous system (CNS) anomalies.

Surgical Outcomes of Acute Retinal Necrosis-Related Retinal Detachment in Polymerase Chain Reaction-Positive Patients: A Single-Center Experience.

PURPOSE: To evaluate the clinical features, operative techniques, and surgical outcomes of patients who underwent surgery for acute retinal necrosis (ARN)-related retinal detachment (RD). DESIGN: Retrospective, longitudinal, consecutive case series. PARTICIPANTS: Patients with polymerase chain reaction-positive ARN presenting from 2011 to 2021 who underwent vitreoretinal surgery for ARN-related RD at our institution. METHODS: Univariate, multivariate, and survival analyses were used to determine predictors of anatomic and functional outcomes. MAIN OUTCOME MEASURES: Single-surgery anatomic success rate, recurrent RD, and visual acuity (VA) at 1 year. RESULTS: Thirty-four eyes of 34 patients (32.4% women, mean age, 45.1 ± 20.4 years) were included for analysis with a median follow-up of 2.5 years (interquartile range [IQR], 0.8-5.5 years). Presenting VA was 1.1 ± 0.8 logarithm of the minimum angle of resolution (LogMAR) (Snellen ∼20/250). The median time from presentation to RD surgery was 1.7 months (IQR, 0.8-4.1 months), and the mean preoperative VA was 1.6 ± 0.8 LogMAR (Snellen ∼20/800). Small-gauge pars plana vitrectomy (PPV) with or without a scleral buckle (SB) was performed for all eyes with an overall single-surgery success rate of 63.6%, with no statistically significant differences in visual/anatomic outcomes between PPV and PPV/SB cases. Silicone oil was used for tamponade in 33 (97.1%) cases and was removed in 10 (30.3%) with good anatomic and final functional outcomes (Snellen âˆ¼20/80). Independent predictors of recurrent RD included the female sex (hazard ratio, 8.38; 95% confidence interval, 2.03-34.68; P < 0.01) and zone 1 retinitis involvement at presentation (hazard ratio, 10.95; 95% confidence interval, 2.12-56.48; P < 0.01). The mean VA at 1 year (VA1year) and at the final follow-up both had a Snellen equivalent of 20/640 (P > 0.05 for both compared with preoperative VA, respectively). Eyes that achieved single-surgery success had VA1year of 20/200 versus hand movements in those with single-surgery failure (P < 0.01). On multivariate linear regression, younger age (P = 0.04) and better presenting VA (P < 0.01) were both associated with better VA1year. CONCLUSIONS: Moderate single-surgery anatomic success can be achieved with modern vitreoretinal surgical techniques for ARN-related RD, although visual outcomes remain poor. Further studies investigating interventions for increasing single-surgery success rates, for the inflammatory complications of ARN, and for preventing ARN-related RD are needed.

Idiopathic Vitreomacular Traction Managed with Initial Observation: Clinical Course and Outcomes.

OBJECTIVE: To review the clinical course and outcomes of patients with idiopathic vitreomacular traction (VMT) managed initially by observation. DESIGN: Retrospective chart review including patients with idiopathic VMT based on clinical symptoms and findings on OCT between January 1, 2015, and February 15, 2021. SUBJECTS: The study included 436 eyes of 317 patients with a mean age of 72.2 years ± 8.9 at initial visit and mean follow-up time of 34 months ± 19.2. METHODS: Vitreomacular traction severity grade was ascribed to each patient using previously published grading criteria. Grade 1 denoted incomplete cortical vitreous separation with attachment at the fovea and visible distortion of the foveal surface. Grade 2 included intraretinal cysts or clefts along with grade 1 findings. Grade 3 included subfoveal fluid along with grade 2 traits. MAIN OUTCOME MEASURES: The rate of spontaneous release, grade at baseline compared with grade at final follow-up, and outcomes of interventions, if performed. RESULTS: At baseline, mean best corrected visual acuity (BCVA) was 20/40. Baseline OCT demonstrated grade 1 VMT in 212 eyes (48.6%), grade 2 VMT in 172 eyes (39.4%), and grade 3 VMT in 52 eyes (11.9%). Among eyes that were initially grade 1, 25.0% had spontaneous release of VMT (median, 290.0 days; mean, 404.5 days ± 323.9), 50.9% remained stable, and 10.4% worsened. Among eyes that were initially grade 2, 14.5% had spontaneous release of VMT (median, 570.0 days; mean, 692.9 days ± 477.5), 55.2% remained stable, 4.7% improved, and 2.3% worsened. Among eyes that were initially grade 3, 5.8% had spontaneous release of VMT (median, 790.0 days; mean, 839.3 days ± 246.7), 28.8% remained stable, and 5.8% improved. Of the 436 eyes, macular hole development occurred in 42 eyes (9.6%). Pars plana vitrectomy was performed in 94 of 436 eyes (21.6%) with mean BCVA before pars plana vitrectomy of 20/78 and final follow-up BCVA of 20/55. CONCLUSION: This study demonstrates the generally stable clinical course of VMT when managed initially by observation. Stable VMT grade was the most frequent outcome, and eyes with grade 1 VMT were more likely to undergo spontaneous release than eyes with grade 2 or 3.

Fibulin-3 knockout mice demonstrate corneal dysfunction but maintain normal retinal integrity.

Fibulin-3 (F3) is an extracellular matrix glycoprotein found in basement membranes across the body. An autosomal dominant R345W mutation in F3 causes a macular dystrophy resembling dry age-related macular degeneration (AMD), whereas genetic removal of wild-type (WT) F3 protects mice from sub-retinal pigment epithelium (RPE) deposit formation. These observations suggest that F3 is a protein which can regulate pathogenic sub-RPE deposit formation in the eye. Yet the precise role of WT F3 within the eye is still largely unknown. We found that F3 is expressed throughout the mouse eye (cornea, trabecular meshwork (TM) ring, neural retina, RPE/choroid, and optic nerve). We next performed a thorough structural and functional characterization of each of these tissues in WT and homozygous (F3-/-) knockout mice. The corneal stroma in F3-/- mice progressively thins beginning at 2 months, and the development of corneal opacity and vascularization starts at 9 months, which worsens with age. However, in all other tissues (TM, neural retina, RPE, and optic nerve), gross structural anatomy and functionality were similar across WT and F3-/- mice when evaluated using SD-OCT, histological analyses, electron microscopy, scotopic electroretinogram, optokinetic response, and axonal anterograde transport. The lack of noticeable retinal abnormalities in F3-/- mice was confirmed in a human patient with biallelic loss-of-function mutations in F3. These data suggest that (i) F3 is important for maintaining the structural integrity of the cornea, (ii) absence of F3 does not affect the structure or function of any other ocular tissue in which it is expressed, and (iii) targeted silencing of F3 in the retina and/or RPE will likely be well-tolerated, serving as a safe therapeutic strategy for reducing sub-RPE deposit formation in disease. KEY MESSAGES: • Fibulins are expressed throughout the body at varying levels. • Fibulin-3 has a tissue-specific pattern of expression within the eye. • Lack of fibulin-3 leads to structural deformities in the cornea. • The retina and RPE remain structurally and functionally healthy in the absence of fibulin-3 in both mice and humans.

Simultaneous Control of Endogenous and User-Defined Genetic Pathways Using Unique ecDHFR Pharmacological Chaperones.

Destabilizing domains (DDs), such as a mutated form of Escherichia coli dihydrofolate reductase (ecDHFR), confer instability and promote protein degradation. However, when combined with small-molecule stabilizers (e.g., the antibiotic trimethoprim), DDs allow positive regulation of fusion protein abundance. Using a combinatorial screening approach, we identified and validated 17 unique 2,4-diaminopyrimidine/triazine-based ecDHFR DD stabilizers, at least 15 of which were ineffective antibiotics against E. coli and S. aureus. Identified stabilizers functioned in vivo to control an ecDHFR DD-firefly luciferase in the mouse eye and/or the liver. Next, stabilizers were leveraged to perform synergistic dual functions in vitro (HeLa cell death sensitization) and in vivo (repression of ocular inflammation) by stabilizing a user-defined ecDHFR DD while also controlling endogenous signaling pathways. Thus, these newly identified pharmacological chaperones allow for simultaneous control of compound-specific endogenous and user-defined genetic pathways, the combination of which may provide synergistic effects in complex biological scenarios.

Delivery of Antisense Oligonucleotides to the Cornea.

Antisense oligonucleotides (ASOs) are synthetic nucleic acids that recognize complementary RNA sequences inside cells and modulate gene expression. In this study, we explore the feasibility of ASO delivery to the cornea. We used quantitative polymerase chain reaction to test the efficacy of a benchmark ASO targeting a noncoding nuclear RNA, Metastasis-Associated Lung Adenocarcinoma Transcript 1 (MALAT1), in a human corneal endothelial cell line, ex vivo human corneas, and in vivo in mice. In vivo delivery was via intravitreal or intracameral injections as well as topical administration. The anti-MALAT1 ASO significantly reduced expression of MALAT1 in a corneal endothelial cell line. We achieved a dose-dependent reduction of target gene expression in endothelial tissue from ex vivo human donor corneas. In vivo mouse experiments confirmed MALAT1 reduction in whole corneal tissue via intravitreal and intracameral routes, 82% and 71% knockdown, respectively (P < 0.001). Effects persisted up to at least 21 days, 32% (P < 0.05) and 43% (P < 0.05) knockdown, respectively. We developed protocols for the isolation and analysis of mouse corneal endothelium and observed reduction in MALAT1 expression upon both intravitreal and intracameral administrations, 64% (P < 0.05) and 63% (P < 0.05) knockdown, respectively. These data open the possibility of using ASOs to treat corneal disease.

Non-antibiotic Small-Molecule Regulation of DHFR-Based Destabilizing Domains In Vivo.

The E. coli dihydrofolate reductase (DHFR) destabilizing domain (DD), which shows promise as a biologic tool and potential gene therapy approach, can be utilized to achieve spatial and temporal control of protein abundance in vivo simply by administration of its stabilizing ligand, the routinely prescribed antibiotic trimethoprim (TMP). However, chronic TMP use drives development of antibiotic resistance (increasing likelihood of subsequent infections) and disrupts the gut microbiota (linked to autoimmune and neurodegenerative diseases), tempering translational excitement of this approach in model systems and for treating human diseases. Herein, we identified a TMP-based, non-antibiotic small molecule, termed 14a (MCC8529), and tested its ability to control multiple DHFR-based reporters and signaling proteins. We found that 14a is non-toxic and can effectively stabilize DHFR DDs expressed in mammalian cells. Furthermore, 14a crosses the blood-retinal barrier and stabilizes DHFR DDs expressed in the mouse eye with kinetics comparable to that of TMP (≤6 h). Surprisingly, 14a stabilized a DHFR DD in the liver significantly better than TMP did, while having no effect on the mouse gut microbiota. Our results suggest that alternative small-molecule DHFR DD stabilizers (such as 14a) may be ideal substitutes for TMP in instances when conditional, non-antibiotic control of protein abundance is desired in the eye and beyond.

A Treatment-Decision Score for HIV-Infected Children With Suspected Tuberculosis.

BACKGROUND: Diagnosis of tuberculosis should be improved in children infected with HIV to reduce mortality. We developed prediction scores to guide antituberculosis treatment decision in HIV-infected children with suspected tuberculosis. METHODS: HIV-infected children with suspected tuberculosis enrolled in Burkina Faso, Cambodia, Cameroon, and Vietnam (ANRS 12229 PAANTHER 01 Study), underwent clinical assessment, chest radiography, Quantiferon Gold In-Tube (QFT), abdominal ultrasonography, and sample collection for microbiology, including Xpert MTB/RIF (Xpert). We developed 4 tuberculosis diagnostic models using logistic regression: (1) all predictors included, (2) QFT excluded, (3) ultrasonography excluded, and (4) QFT and ultrasonography excluded. We internally validated the models using resampling. We built a score on the basis of the model with the best area under the receiver operating characteristic curve and parsimony. RESULTS: A total of 438 children were enrolled in the study; 251 (57.3%) had tuberculosis, including 55 (12.6%) with culture- or Xpert-confirmed tuberculosis. The final 4 models included Xpert, fever lasting >2 weeks, unremitting cough, hemoptysis and weight loss in the past 4 weeks, contact with a patient with smear-positive tuberculosis, tachycardia, miliary tuberculosis, alveolar opacities, and lymph nodes on the chest radiograph, together with abdominal lymph nodes on the ultrasound and QFT results. The areas under the receiver operating characteristic curves were 0.866, 0.861, 0.850, and 0.846, for models 1, 2, 3, and 4, respectively. The score developed on model 2 had a sensitivity of 88.6% and a specificity of 61.2% for a tuberculosis diagnosis. CONCLUSIONS: Our score had a good diagnostic performance. Used in an algorithm, it should enable prompt treatment decision in children with suspected tuberculosis and a high mortality risk, thus contributing to significant public health benefits.

Branching of hydraulic cracks enabling permeability of gas or oil shale with closed natural fractures.

While hydraulic fracturing technology, aka fracking (or fraccing, frac), has become highly developed and astonishingly successful, a consistent formulation of the associated fracture mechanics that would not conflict with some observations is still unavailable. It is attempted here. Classical fracture mechanics, as well as current commercial software, predict vertical cracks to propagate without branching from the perforations of the horizontal well casing, which are typically spaced at 10 m or more. However, to explain the gas production rate at the wellhead, the crack spacing would have to be only about 0.1 m, which would increase the overall gas permeability of shale mass about 10,000×. This permeability increase has generally been attributed to a preexisting system of orthogonal natural cracks, whose spacing is about 0.1 m. However, their average age is about 100 million years, and a recent analysis indicated that these cracks must have been completely closed by secondary creep of shale in less than a million years. Here it is considered that the tectonic events that produced the natural cracks in shale must have also created weak layers with nanocracking or microcracking damage. It is numerically demonstrated that seepage forces and a greatly enhanced permeability along the weak layers, with a greatly increased transverse Biot coefficient, must cause the fracking to engender lateral branching and the opening of hydraulic cracks along the weak layers, even if these cracks are initially almost closed. A finite element crack band model, based on a recently developed anisotropic spherocylindrical microplane constitutive law, demonstrates these findings [Rahimi-Aghdam S, et al. (2018) arXiv:1212.11023].