Utilizing Zebrafish Visual Behaviors in Drug Screening for Retinal Degeneration

Zebrafish are a popular vertebrate model in drug discovery. They produce a large number of small and rapidly-developing embryos. These embryos display rich visual-behaviors that can be used to screen drugs for treating retinal degeneration (RD). RD comprises blinding diseases such as Retinitis Pigmentosa, which affects 1 in 4000 people. This disease has no definitive cure, emphasizing an urgency to identify new drugs. In this review, we will discuss advantages, challenges, and research developments in using zebrafish behaviors to screen drugs in vivo. We will specifically discuss a visual-motor response that can potentially expedite discovery of new RD drugs

Detection of microalbuminuria in non-insulin dependent diabetes mellitus (NIDDM) patients without overt proteinuria by a semiquantitative albumin-creatinine urine strips

AbstractMicroalbuminuria is the hallmark of the reversible stage of incipient diabetic nephropathy. A cost- effective and convenient bedside screening test is essential to detect this phase. We used Clinitek 50® which is a semiquantitative strip test to check spot urine sample from 81 patients with albustix one plus or less. The incidence of Clinitek 50® microalbuminuria was 17%, 18.2% and 75% in 47, 22 and 12 patients with albustix negative, trace or one plus respectively. Nineteen and 13 of the 21 Clinitek 50® positive patients were checked for spot urine DCA 2000® and two 12-hour urine collection for immunoassay respectively. Around 60% of these samples fell into the microalbuminuria range and 40% into the overt albuminuria range by either technique. There was no false positive of Clinitek 50®. The lowest range of microalbuminuria detected by Clinitek 50® was 27 μg/minute (38 mg/day). We concluded that Clinitek 50® is a useful screening test as it is nonexpensive, easily operated and has a sensitivity close to the lower range of microalbuminuria

Association between serum uric acid and prostate cancer mortality in androgen deprivation therapy: A population‐based cohort study

Objective This population-based study examined the association between baseline uric acid (UA) and prostate cancer (PCa)-related mortality amongst PCa patients receiving androgen deprivation therapy (ADT). Methods Adults with PCa who received ADT in Hong Kong between December 1999 and March 2021 were identified. Patients with missing baseline UA were excluded. Patients were followed up until September 2021. The outcome was PCa-related mortality. Results Altogether, 4126 patients (median follow-up 3.1[interquartile range 1.4–6.0] years) were included. A J-shaped association was observed between baseline UA level and PCa-related mortality risk, with a direct association in those with mean(0.401 mmol/L) or above-mean baseline UA levels (hazard ratio (HR) per standard deviation-increase 1.35 [95% confidence interval 1.21,1.51], p < 0.001), and an inverse association in those with below-mean baseline UA levels (HR 0.78[0.67,0.92], p = 0.003). The former remained significant on competing risk regression, but not the latter. Conclusions A J-shaped relationship between baseline UA level and PCa-related mortality risk was identified. This study was mainly limited by potential unmeasured and residual confounders. Further validation studies are warranted

Expression profiling of the retina of pde6c, a zebrafish model of retinal degeneration

Retinal degeneration often affects the whole retina even though the disease-causing gene is specifically expressed in the light-sensitive photoreceptors. The molecular basis of the retinal defect can potentially be determined by gene-expression profiling of the whole retina. In this study, we measured the gene-expression profile of retinas microdissected from a zebrafish pde6cw59 (pde6c) mutant. This retinal-degeneration model not only displays cone degeneration caused by a cone-specific mutation, but also other secondary cellular changes starting from 4 days postfertilization (dpf). To capture the underlying molecular changes, we subjected pde6c and wild-type (WT) retinas at 5 dpf/ 120 h postfertilization (hpf) to RNA sequencing (RNA-Seq) on the Illumina HiSeq 2,000 platform. We also validated the RNA-Seq results by Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) of seven phototransduction genes. Our analyses indicate that the RNA-Seq dataset was of high quality, and effectively captured the molecular changes in the whole pde6c retina. This dataset will facilitate the characterization of the molecular defects in the pde6c retina at the initial stage of retinal degeneration