A study of histopathological features of latanoprost-treated irides with or without darkening compared with non-latanoprost-treated irides

Kafka's beautiful eyes: Forensic intelligence utilisation of phenotypic information

Franz Kafka had beautiful eyes. So striking, that many of the famous author's friends and peers commented on them - but quite variously ('dark', 'brown', 'grey' & 'blue'). Eye colour as perceived by an observer is subjective, being influenced by physiological, environmental, and even sociocultural factors. In a policing context, this does not mean that trait information such as eye colour is not valuable (far from it), but that it must be managed carefully. The Australian Federal Police has recently implemented a forensic DNA phenotyping (FDP, aka. physical trait prediction or PTP) capability, utilising massively parallel sequencing DNA technology to predict an individual's eye colour, biogeographical ancestry and sex from a crime scene sample. This information alone is not itself 'intelligence', but can be used to generate intelligence through holistic analyses undertaken within a transdisciplinary, all-source forensic intelligence (FORINT) framework. FORINT outputs posit abductive propositions typically at the activity/offence level, to provide insight and influence decision making. However, the use of predicted traits requires that they are compared to something; all Australian police databases include fields for physical traits, but no uniform standard is applied across all agencies. Moreover, collection is inconsistent and no automated systems are in place to capture such data systematically. Consider the 'Kafka problem': his peers gave multiply divergent descriptions of his eyes. If a Biology unit had predicted the eye colour of an 'unidentified author' using DNA - how would Kafka be confidently nominated as the contributor? We posit three maxims for law enforcement: (1) To expand the operational utility of forensic science in line with police demands, forensic science should operationalise FDP (e.g. operationally to rank a list of persons of interest, focus lines of enquiry in serious & organised crime, or assist with human remains identification). (2) Such advanced biological techniques are best delivered through an all-source FORINT framework, to maximise opportunities and minimise risk. (3) One cannot pursue techno-scientific advancements in isolation; it is also necessary to influence the operational posture for their implementation. In this paper we explore these issues and provide recommendations relating to (a) police practices, (b) image capture systems, and (c) research opportunities. Phenotypic trait prediction has great potential and can be operationalised effectively through a rigorous FORINT framework. However, there is (continual) work to be done to enhance the operational capabilities that are complementary to - but necessary for - effective forensic science contribution to investigations.

In-vivo inhibition of latanoprost induced iridal hyperpigmentation in rabbits- An investigational study

Objectives

To evaluate the inhibitory effects of different concentrations of α-methyl-DL-tyrosine on latanoprost-induced iridal hyperpigmentation in rabbits.

Methods

We investigated 4 groups of rabbits. Both eyes of the pink, red, and blue groups were treated with latanoprost followed by 0.5%, 1%, and 2% α-methyl-DL-tyrosine (inhibitor) in the right eyes respectively and the green group received only inhibitor. We prospectively investigated the irides, estimated quantitatively total melanin contents, and studied any histopathological changes that occurred.

Results

The observers favored hyperpigmentation in the left eyes while in the right eyes they noted a decrease in pigmentation as compared to the baseline. An increase in pigmentation was noted by 93.33% of observers in the left eye of the blue group. A significant difference in the mean melanin contents was noted in the blue group (Right eye = 09.560 μg/g (±0.750), Left eye = 3.730 μg/g (±1.062). There was no evidence of stromal malignant changes, Hemorrhage, mitosis, inflammation, and atypical melanocytes in all specimens. A moderate degree of pigmentation in the left eye of the red group was noted. Mild stromal-free melanin pigment was present in all samples of pink, red and blue groups.

Conclusions

The α-methyl-DL-tyrosine significantly inhibited latanoprost-induced iridal pigmentation without causing any histopathological changes at a 2% dose.

Anterior Segment Optical Coherence Tomography Analysis of Iris Morphometric Changes Induced by Prostaglandin Analogues Treatment in Patients with Primary Open Angle Glaucoma or Ocular Hypertension

Background:

The study aimed to evaluate iris thickness changes in patients with Primary Open Angle Glaucoma (POAG) or Ocular Hypertension (OHT) under treatment with Prostaglandin Analogues (PG).

Objectives:

Primary outcome measures were iris thickness at the region of Dilator Muscle Region (DMR) and Sphincter Muscle Region (SMR). DMR/SMR ratio was also evaluated. The secondary outcome was the correlation between PG treatment length and iris parameters.

Methods:

The charts of patients with POAG or OHT who underwent Visante OCT were retrospectively selected. The patients were divided in a group using PG for at least 6 months and a group using hypotensive drops not including PG or alpha-adrenergic agonists. A third group included healthy subjects.

Result:

98 subjects were selected. Patients with POAG or OHT using PG eyedrops showed a significant iris thickness reduction at DMR compared to healthy subjects and to patients using hypotensive eyedrops not containing PG. Significantly higher SMR thickness values were found in PG group compared to both control groups. DMR/SMR ratio significantly reduced in PG group. No correlation was found between PG treatment length and iris parameters.

Conclusion:

The present data indicate that PG treatment induced DMR thickness reduction and an increase in SMR thickness. These changes were not related to the duration of PG exposure.

Pharmacology of topical prostaglandin F2 α analogs and their place in the treatment of glaucoma in small animals

A distinguishing feature of the most common types of glaucoma is an increased intra-ocular pressure (IOP), which has a damaging effect on optic nerve axons, leading to the progressive loss of retinal ganglion cells. Therefore, IOP-lowering medications are the mainstay of glaucoma therapy. Topical prostaglandin F2 α analogs (PGAs) are a relatively new class of ocular hypotensive drugs, which have made a huge impact on the treatment of glaucoma in dogs. This study summarizes the current state of knowledge on the mechanism of action of these agents and their effect on IOP in dogs and cats. It also discusses potential harmful side effects of PGAs and presents contemporary opinions about their role and place in the medical management of glaucoma in small animals.

Long-term efficacy of latanoprost in primary congenital glaucoma

PURPOSE

To investigate the success (glaucoma control) of latanoprost therapy of primary congenital glaucoma (PCG) and factors affecting the long-term outcome.

METHODS

Patients with PCG treated with latanoprost were re-examined. At study visit and from clinical charts, we evaluated: intraocular pressure, length of glaucoma control with latanoprost, need of further medication or glaucoma surgery, systemic and topical side effects. Multivariate analysis was used to test factors related to the final outcome of the treatment.

RESULTS

Eighty-one eyes of 44 patients with PCG, and 42 eyes of 29 patients with previous glaucoma surgery, had received latanoprost therapy. In the first group, a success (glaucoma control by latanoprost therapy) was found in 24 eyes (29.6%), whereas 57 eyes (70.4%) had received surgery (45 eyes (55.6%) in the first year); among the eyes with previous surgery, a success was found in 12 eyes (28.6%), 13 eyes (31%) required an additional therapy, and 17 eyes (40.5%) had received further glaucoma surgery. No patient discontinued the treatment because of side effects. Factors related to the failure of the latanoprost treatment were: the high score of severity of glaucoma (P=0.014) and low age at PCG presentation (P=0.042).

CONCLUSIONS

Long-term treatment with latanoprost is effective in about 30% of the eyes; factors related to failure were severe glaucomatous alterations, and young age at PCG presentation.

Drug-induced hperpigemntation: a systematic review

BACKGROUND

Acquired hyperpigmentation of the skin is sometimes interpreted as an adverse effect of drugs. Systematic studies are rare in the literature; predominantly case reports have been published. The present review provides evaluates the evidence for a causal relation.

METHODS

The reports on a relationship between hyperpigmentation and drugs from 1970 until June 2012 found in MEDLINE and EMBASE were rated according to the SIGN grading system for clinical studies. In this system, the grade of evidence of each report is rated. The highest grade of evidence for each drug is cited.

RESULTS

306 publications were included. They were predominantly case reports; only a small number of case series was available. Only very few case-control-studies and randomized controlled trials (RCT) were found. For the majority of drugs, there was a low level of evidence for a causal relationship in drug-induced hyperpigmentation. A causal relationship is likely only for prostaglandins, minocycline, phenothiazine, nicotine, and antimalarial drugs.

CONCLUSIONS

There is little evidence for drug-induced hyperpigmentation. A causal relationship appears liklely only for a limited number of drugs.