Skunk River Review September 1989, vol 1 no 1

https://openspace.dmacc.edu/skunkriver/1004/thumbnail.jp

Inducible Ablation of Melanopsin-Expressing Retinal Ganglion Cells Reveals Their Central Role in Non-Image Forming Visual Responses

Rod/cone photoreceptors of the outer retina and the melanopsin-expressing retinal ganglion cells (mRGCs) of the inner retina mediate non-image forming visual responses including entrainment of the circadian clock to the ambient light, the pupillary light reflex (PLR), and light modulation of activity. Targeted deletion of the melanopsin gene attenuates these adaptive responses with no apparent change in the development and morphology of the mRGCs. Comprehensive identification of mRGCs and knowledge of their specific roles in image-forming and non-image forming photoresponses are currently lacking. We used a Cre-dependent GFP expression strategy in mice to genetically label the mRGCs. This revealed that only a subset of mRGCs express enough immunocytochemically detectable levels of melanopsin. We also used a Cre-inducible diphtheria toxin receptor (iDTR) expression approach to express the DTR in mRGCs. mRGCs develop normally, but can be acutely ablated upon diphtheria toxin administration. The mRGC-ablated mice exhibited normal outer retinal function. However, they completely lacked non-image forming visual responses such as circadian photoentrainment, light modulation of activity, and PLR. These results point to the mRGCs as the site of functional integration of the rod/cone and melanopsin phototransduction pathways and as the primary anatomical site for the divergence of image-forming and non-image forming photoresponses in mammals

The Neuropeptide Allatostatin A Regulates Metabolism and Feeding Decisions in Drosophila

Coordinating metabolism and feeding is important to avoid obesity and metabolic diseases, yet the underlying mechanisms, balancing nutrient intake and metabolic expenditure, are poorly understood. Several mechanisms controlling these processes are conserved in Drosophila, where homeostasis and energy mobilization are regulated by the glucagon-related adipokinetic hormone (AKH) and the Drosophila insulin-like peptides (DILPs). Here, we provide evidence that the Drosophila neuropeptide Allatostatin A (AstA) regulates AKH and DILP signaling. The AstA receptor gene, Dar-2, is expressed in both the insulin and AKH producing cells. Silencing of Dar-2 in these cells results in changes in gene expression and physiology associated with reduced DILP and AKH signaling and animals lacking AstA accumulate high lipid levels. This suggests that AstA is regulating the balance between DILP and AKH, believed to be important for the maintenance of nutrient homeostasis in response to changing ratios of dietary sugar and protein. Furthermore, AstA and Dar-2 are regulated differentially by dietary carbohydrates and protein and AstA-neuronal activity modulates feeding choices between these types of nutrients. Our results suggest that AstA is involved in assigning value to these nutrients to coordinate metabolic and feeding decisions, responses that are important to balance food intake according to metabolic needs

EFEKTIVITAS PENGAWASAN UNIT KERJA ANTI FRAUD PADA BANK MUAMALAT INDONESIA

Perkembangan perbankan syari‟ah di Indonesia demikian pesat yang ditandai dengan berdirinya Bank Muamalat Indonesia. Perkembangan ini berimplikasi pada besarnya tantangan perbankan syari‟ah di Indonesia terutama dalam mempertahankan identitasnya sebagai perusahaan yang bergerak berlandaskan prinsip-prinsip syari‟ah. Sejak berdirinya perbankan syariah,berbagai kontroversi muncul dari masyarakat, masalah yang paling banyak disorot adalah pelekatan label syariah pada institusi keuangan Islam yang masih dianggap belum layak. Keraguan masyarakat tersebut seolah terjawab dengan munculnya kasus yang cukup menggemparkan yakni kasus fraud (tindak kecurangan) yang terjadi di lembaga syariah. Bank Muamalat Indonesia merupakan bank syari‟ah pertama yang muncul dengan gagasan bank murni syari‟ah. Akan tetapi, bank Muamalat Indonesia juga tak luput dari kasus fraud yang dilakukan oleh karyawan bank tersebut. Berdasarkan Laporan Tahunan BMI menyebutkan bahwa telah terjadi peningkatan kasus fraud dari tahun sebelumnya yang berjumlah 18 kasus menjadi 82 kasus pada tahun 2016. Padahal perusahaan yang menggunakan identitas syariah seharusnya dapat lebih meminimalisir bahkan meniadakan resiko terjadinya kasus fraud dengan adanya internal control perusahaan. Dari latar belakang tersebut, peneliti berusaha mendalami peran pengawasan Unit Kerja Anti Fraud dalam fraud preventive pada Bank Muamalat Indonesia. Penelitian ini merupakan penelitin pustaka yang bersifat deskriptif analisis dengan pendekatan kualitatif. Adapun sumber bahan hukum primer yang dipakai yaitu berdasarkan Laporan Tahunan Bank Muamalat Indonesia Tahun 2016. Sedangkan sumber bahan hukum sekunder berupa buku-buku, jurnal,karya ilmiah, artikel, terkait dengan strategi anti fraud perbankan syariah. Dari hasil penelitian dikemukakan bahwa peningkatan kasus fraud yang terjadi pada Bank Muamalat Indonesia disebabkan kurang efektifnya pengawasan Unit Kerja Anti Fraud. Hal ini dikarenakan kegiatan yang dilakukan selama tahun 2016 belum menujukkan adanya usaha preventif terhadap kasus fraud. Sedangkan pencegahan merupakan pilar penting dalam keefektivan sebuah pengawasan. Tujuan perusahaan dalam mencegah fraud dapat tercapai, jika fungsi pengawasan dilakukan sebelum terjadinya penyimpangan-penyimpangan sehingga lebih bersifat mencegah (prefentive control). Oleh karena itu, keefektivan pengawasan Unit Kerja Anti Fraud diharapkan dapat meminimalisir tindak kecurangan demi mewujudkan perusahaan yang patuh terhadap ketentuan syariah sesuai dengan identitas perusahaan. vii Usaha pencegahan terjadinya kasus pada Bank Muamalat Indonesia diharapkan dapat menjadi bukti terlaksananya tatakelola perusahaan (Good Corporate Governance) pada Bank Syari‟ah dengan baik. Hal ini berdasarkan dalam dalam perbankan syariah dikenal adanya prinsip-prinsip syariah yang mendukung bagi terlaksananya prinsip GCG yakni keharusan bagi subjek hukum termasuk bank untuk menerapkan prinsip kejujuran (shiddiq), edukasi kepada masyarakat (tabligh), kepercayaan (amanah), dan pengelolaan secara profesional (fathanah)

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

A network centered on ventral premotor cortex exerts both facilitatory and inhibitory control over primary motor cortex during action reprogramming.

Ventral premotor cortex (PMv) is widely accepted to exert an important influence over primary motor cortex (M1) when hand movements are made. Although study of these interactions has typically focused on their excitatory nature, given its strong connections with both ventral and opercular frontal regions, one feature of the influence of PMv over M1 may be inhibitory. Paired-pulse transcranial magnetic stimulation (ppTMS) was used to examine functional interactions between human PMv and M1 during the selection and reprogramming of a naturalistic goal-directed action. One of two cylinders was illuminated on each trial. It was then grasped and picked up. On some trials, however, subjects had to reprogram the action as the illuminated cylinder was switched off and the other illuminated simultaneously with reach initiation. At a neurophysiological level, the PMv paired-pulse effect (PPE) on M1 corticospinal activity was facilitatory after the initial target presentation and during movement initiation. When reprogramming was required, however, the PPE became strongly inhibitory. This context-dependent change from facilitation to inhibition occurred within 75 ms of the change of target. Behaviorally, PMv-M1 ppTMS disrupted reprogramming. Diffusion-weighted magnetic resonance image scans were taken of each subject. Intersubject differences in the facilitation-inhibition contrast of PMv-M1 interactions were correlated with fractional anisotropy of white-matter in ventral prefrontal, premotor, and intraparietal brain areas. These results suggest that a network of brain areas centered on PMv inhibits M1 corticospinal activity associated with undesired movements when action plans change

Short-latency influence of medial frontal cortex on primary motor cortex during action selection under conflict.

Medial frontal cortex (MFC) is crucial when actions have to be inhibited, reprogrammed, or selected under conflict, but the precise mechanism by which it operates is unclear. Importantly, how and when the MFC influences the primary motor cortex (M1) during action selection is unknown. Using paired-pulse transcranial magnetic stimulation, we investigated functional connectivity between the presupplementary motor area (pre-SMA) part of MFC and M1. We found that functional connectivity increased in a manner dependent on cognitive context: pre-SMA facilitated the motor evoked-potential elicited by M1 stimulation only during action reprogramming, but not when otherwise identical actions were made in the absence of conflict. The effect was anatomically specific to pre-SMA; it was not seen when adjacent brain regions were stimulated. We discuss implications for the anatomical pathways mediating the observed effects