The transition time to gambling disorder: The roles that age, gambling preference and personality traits play

BACKGROUND AND AIMS

Gambling Disorder (GD) is considered a heterogeneous, multidimensional pathology with high personal and social consequences. The transition time (TT) between problematic gaming and pathological gambling, which varies significantly across patients, may predict the disorder's severity. As only limited studies have investigated the factors implicated in the TT, the current study set out to identify its predictors and their relationships with GD severity.

METHODS

Correlation were performed in 725 male GD patients to identify factors associated to TT and GD severity, including: age of onset of gambling behaviors, alcohol/drug use, personality traits and gambling preferences (i.e., strategic, non-strategic, and mixed). Then a regression analysis was performed to identify predictors of TT to GD.

RESULTS

Longer TT correlated with higher GD severity, early age of onset of problematic gambling, substance use and a non-strategic gambling preference. Personality traits including low self-directedness, high novelty seeking, and low cooperativeness were also related with longer TT. The strongest associations with GD severity were substance use, and some of the personality traits (i.e., low self-directedness and cooperativeness, high harm avoidance and self-transcendence). Factors significantly predicting longer transition to GD were older ages, low self-directedness, and non-strategic gambling.

CONCLUSIONS

A clinical profile characterized by a longer TT and more severe GD symptoms pertains to older patients with low self-directedness, and preference for non-strategic gambling. Other relevant factors associated with this profile of patients included early age of onset problematic gambling, substance consumption, high novelty seeking and low cooperativeness.

Morphological quantification of proliferation-to-invasion transition in tumor spheroids

BACKGROUND

Metastasis determines the lethality of cancer. In most clinical cases, patients are able to live with tumor proliferation before metastasis. Thus, the transition from tumor proliferation to metastasis/invasion is essential. However, the mechanism is still unclear and especially, the proliferation-to-metastasis/invasion transition point has not been well defined. Therefore, quantitative characterization of this transition is urgently needed.

METHODS

We have successfully developed a home-built living-cell incubation system combined with an inverted optical microscope, and a systematic, quantitative approach to describing the major characteristic morphological parameters for the identification of the critical transition points for tumor-cell spheroids in a collagen fiber scaffold.

RESULTS

The system focuses on in vitro tumor modeling, e.g. the development of tumor-cell spheroids in a collagen fiber scaffold and the monitoring of cell transition from proliferation to invasion. By applying this approach to multiple tumor spheroid models, such as U87 (glioma tumor), H1299 (lung cancer), and MDA-MB-231 (breast cancer) cells, we have obtained quantitative morphological references to evaluate the proliferation-to-invasion transition time, as well as differentiating the invasion potential of tumor cells upon environmental changes, i.e. drug application.

CONCLUSIONS

Our quantitative approach provides a feasible clarification for the proliferation-to-invasion transition of in vitro tumor models (spheroids). Moreover, the transition time is a useful reference for the invasive potential of tumor cells.

GENERAL SIGNIFICANCE

This quantitative approach is potentially applicable to primary tumor cells, and thus has potential applications in the fields of cancer metastasis investigations and clinical diagnostics.

No more conventional reference electrode: transition time for determining chloride ion concentration

Ion selective electrodes (ISE) are used extensively for the potentiometric determination of ion concentrations in electrolytes. However, the inherent drift in these measurements and the requirement of a stable reference electrode restrict the feasibility of this method for long-term in-situ applications. This work presents a chronopotentiometric approach to minimize drift and avoid the use of a conventional reference electrode for measuring chloride ion concentration. An anodic current pulse is applied to a Ag/AgCl working electrode which initiates a faradaic reaction that depletes the chloride ions near the electrode surface. The rate of change in potential at the Ag/AgCl electrode, due to chloride ion depletion, reaches an inflection point once the chloride ions deplete completely near the electrode surface. The moment of the inflection point, also known as the transition time, is a function of the chloride ion concentration and is described by the Sand equation. It is shown that the square root of the transition time is linearly proportional to the chloride ion concentration. Drift in the response over two weeks is negligible: 59 μM/day when measuring 1 mM of Cl(-) ions using a 10 A m(-2) current pulse. The transition time at a specific ion concentration can be tuned by the applied current pulse, e.g., in a solution containing 5 mM chloride ions, the transition times with current pulses of 10 and 20 A m(-2) are 1.56 and 0.25s, respectively. The moment of inflection determines the response, and thus is independent of the absolute potential of reference electrode. Therefore, any metal wire can act as a pseudo-reference electrode, enabling this approach for long-term and integrated-sensor applications such as measurement inside concrete structures.