Excess capital and bank behavior : evidence from Indonesia

The Indonesian banking sector has been restructured since Asian financial crisis and restored to soundness. The capital adequacy ratio (CAR) returned to a sound level; however, the average excess capital has become too high, while credit disbursement has remained low. This paper investigates the determinants of excess capital among Indonesian banks and its effects on credit growth during the 2000s. The results indicate that the determinants of excess capital vary widely depending on bank type. Return on equity (ROE) affects excess capital negatively among domestic banks, and the effect of non-performing loans is mixed, differing for various bank types. Excess capital affects credit growth positively, except among foreign banks.

Transient excess of MYC activity can elicit genomic instability and tumorigenesis

Overexpression of the MYC protooncogene has been implicated in the genesis of diverse human tumors. Tumorigenesis induced by MYC has been attributed to sustained effects on proliferation and differentiation. Here we report that MYC may also contribute to tumorigenesis by destabilizing the cellular genome. A transient excess of MYC activity increased tumorigenicity of Rat1A cells by at least 50-fold. The increase persisted for >30 days after the return of MYC activity to normal levels. The brief surfeit of MYC activity was accompanied by evidence of genomic instability, including karyotypic abnormalities, gene amplification, and hypersensitivity to DNA-damaging agents. MYC also induced genomic destabilization in normal human fibroblasts, although these cells did not become tumorigenic. Stimulation of Rat1A cells with MYC accelerated their passage through G1/S. Moreover, MYC could force normal human fibroblasts to transit G1 and S after treatment with N-(phosphonoacetyl)-l-aspartate (PALA) at concentrations that normally lead to arrest in S phase by checkpoint mechanisms. Instead, the cells subsequently appeared to arrest in G2. We suggest that the accelerated passage through G1 was mutagenic but that the effect of MYC permitted a checkpoint response only after G2 had been reached. Thus, MYC may contribute to tumorigenesis through a dominant mutator effect.

Steroid disorders in children: Congenital adrenal hyperplasia and apparent mineralocorticoid excess

Our research team and laboratories have concentrated on two inherited endocrine disorders, congenital adrenal hyperplasia (CAH) and apparent mineralocorticoid excess, in thier investigations of the pathophysiology of adrenal steroid hormone disorders in children. CAH refers to a family of inherited disorders in which defects occur in one of the enzymatic steps required to synthesize cortisol from cholesterol in the adrenal gland. Because of the impaired cortisol secretion, adrenocorticotropic hormone levels rise due to impairment of a negative feedback system, which results in hyperplasia of the adrenal cortex. The majority of cases is due to 21-hydroxylase deficiency (21-OHD). Owing to the blocked enzymatic step, cortisol precursors accumulate in excess and are converted to potent androgens, which are secreted and cause in utero virilization of the affected female fetus genitalia in the classical form of CAH. A mild form of the 21-OHD, termed nonclassical 21-OHD, is the most common autosomal recessive disorder in humans, and occurs in 1/27 Ashkenazic Jews. Mutations in the CYP21 gene have been identified that cause both classical and nonclassical CAH. Apparent mineralocorticoid excess is a potentially fatal genetic disorder causing severe juvenile hypertension, pre- and postnatal growth failure, and low to undetectable levels of potassium, renin, and aldosterone. It is caused by autosomal recessive mutations in the HSD11B2 gene, which result in a deficiency of 11β-hydroxysteroid dehydrogenase type 2. In 1998, we reported a mild form of this disease, which may represent an important cause of low-renin hypertension.

Excess “read-through” acetylcholinesterase attenuates but the “synaptic” variant intensifies neurodeterioration correlates

Acute stress increases the risk for neurodegeneration, but the molecular signals regulating the shift from transient stress responses to progressive disease are not yet known. The “read-through” variant of acetylcholinesterase (AChE-R) accumulates in the mammalian brain under acute stress. Therefore, markers of neurodeterioration were examined in transgenic mice overexpressing either AChE-R or the “synaptic” AChE variant, AChE-S. Several observations demonstrate that excess AChE-R attenuates, whereas AChE-S intensifies, neurodeterioration. In the somatosensory cortex, AChE-S transgenics, but not AChE-R or control FVB/N mice, displayed a high density of curled neuronal processes indicative of hyperexcitation. In the hippocampus, AChE-S and control mice, but not AChE-R transgenics, presented progressive accumulation of clustered, heat shock protein 70–immunopositive neuronal fragments and displayed a high incidence of reactive astrocytes. Our findings suggest that AChE-R serves as a modulator that may play a role in preventing the shift from transient, acute stress to progressive neurological disease.