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1.
J Med Chem ; 66(5): 3195-3211, 2023 03 09.
Article in English | MEDLINE | ID: mdl-36802610

ABSTRACT

The melanocortin-4 receptor (MC4R) is a centrally expressed, class A GPCR that plays a key role in the regulation of appetite and food intake. Deficiencies in MC4R signaling result in hyperphagia and increased body mass in humans. Antagonism of MC4R signaling has the potential to mitigate decreased appetite and body weight loss in the setting of anorexia or cachexia due to underlying disease. Herein, we report on the identification of a series of orally bioavailable, small-molecule MC4R antagonists using a focused hit identification effort and the optimization of these antagonists to provide clinical candidate 23. Introduction of a spirocyclic conformational constraint allowed for simultaneous optimization of MC4R potency and ADME attributes while avoiding the production of hERG active metabolites observed in early series leads. Compound 23 is a potent and selective MC4R antagonist with robust efficacy in an aged rat model of cachexia and has progressed into clinical trials.


Subject(s)
Appetite , Receptor, Melanocortin, Type 4 , Rats , Humans , Animals , Cachexia/drug therapy , Anorexia/drug therapy , Molecular Conformation
2.
Cutis ; 110(2): 86-87, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36219643

ABSTRACT

Nonmelanoma skin cancer is the most common cancer, typically growing in sun-exposed areas, such as the nose. After complete excision of the tumor, the subsequent scar may exhibit multiple complications that are easily noticeable and cosmetically unsatisfactory. When performing a revision of such a scar, using a single surgical technique may be insufficient; rather, the surgeon may need to carefully plan and utilize several techniques to achieve the best cosmetic outcome. Here, we report a case that demonstrates successful use of surgical defatting and Z-plasty techniques to revise a scar of the nasal dorsum that exhibited pincushioning and webbing.


Subject(s)
Plastic Surgery Procedures , Skin Neoplasms , Cicatrix/etiology , Cicatrix/surgery , Humans , Nose/surgery , Plastic Surgery Procedures/methods , Skin Neoplasms/complications , Skin Neoplasms/surgery
3.
iScience ; 25(9): 104944, 2022 Sep 16.
Article in English | MEDLINE | ID: mdl-36065181

ABSTRACT

BRCA1 maintains genome stability by promoting homologous recombination (HR)-mediated DNA double-strand break (DSB) repair. Mutation of mouse BRCA1-S1152, corresponding to an ATM phosphorylation site in its human counterpart, resulted in increased genomic instability and tumor incidence. In this study, we report that BRCA1-S1152 is part of a feedback loop that sustains ATM activity. BRCA1-S1152A mutation impairs recruitment of the E3 ubiquitin ligase SKP2. This in turn attenuates NBS1-K63 ubiquitination by SKP2 at DSB, impairs sustained ATM activation, and ultimately leads to deficient end resection, the commitment step in the HR repair pathway. Auto-phosphorylation of human ATM at S1981 is known to be important for its kinase activation; we mutated the corresponding amino acid residue in mouse ATM (S1987A) to characterize potential roles of mouse ATM-S1987 in the BRCA1-SKP2-NBS1-ATM feedback loop. Unexpectedly, MEFs carrying the ATM-S1987A knockin mutation maintain damage-induced ATM kinase activation, suggesting a species-specific function of human ATM auto-phosphorylation.

4.
Dermatol Online J ; 28(5)2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36809140

ABSTRACT

We describe an HIV-negative 43-year-old woman presenting with a diffuse ulceronodular eruption and positive serological tests for syphilis consistent with lues maligna. Lues maligna is a severe and rare variant of secondary syphilis characterized by prodromal constitutional symptoms followed by the formation of multiple well-circumscribed nodules with ulceration and crust. This case depicts a particularly rare presentation as lues maligna usually involves HIV-positive men. The clinical presentation of lues maligna can pose a diagnostic challenge, with infections, sarcoidosis, and cutaneous lymphoma as just a few entities in its broad differential diagnosis. However, with a high index of suspicion, clinicians can diagnose and treat this entity earlier and reduce morbidity.


Subject(s)
HIV Infections , Skin Neoplasms , Skin Ulcer , Syphilis, Cutaneous , Syphilis , Male , Female , Humans , Adult , Syphilis/diagnosis , Syphilis, Cutaneous/diagnosis , HIV Infections/complications , Skin Ulcer/pathology , Skin Neoplasms/complications
5.
Mod Pathol ; 35(5): 632-639, 2022 05.
Article in English | MEDLINE | ID: mdl-34802044

ABSTRACT

Small B-cell lymphoid neoplasms (SBCLNs) are a heterogeneous group of diseases characterized by malignant clonal proliferation of mature B-cells. However, the classification of SBCLNs remains a challenge, especially in cases where histopathological analysis is unavailable or those with atypical laboratory findings or equivocal pathologic data. In this study, gene expression profiling of 1039 samples from 27 gene expression omnibus (GEO) datasets was first investigated to select highly and differentially expressed genes among SBCLNs. Samples from 57 SBCLN cases and 102 nonmalignant control samples were used to train a classifier using the NanoString platform. The classifier was built by employing a cascade binary classification method based on the random forest algorithm with 35 refined gene signatures. Cases were successively classified as chronic lymphocytic leukemia/small lymphocytic lymphoma, conventional mantle cell lymphoma, follicular lymphoma, leukemic non-nodal mantle cell lymphoma, marginal zone lymphoma, lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia, and other undetermined. The classifier algorithm was then validated using an independent cohort of 197 patients with SBCLNs. Under the distribution of our validation cohort, the overall sensitivity and specificity of proposed algorithm model were >95%, respectively, for all the cases with tumor cell content greater than 0.72. Combined with additional genetic aberrations including IGH-BCL2 translocation, MYD88 L265P mutation, and BRAF V600E mutation, the optimal sensitivity and specificity were respectively found at 0.88 and 0.98. In conclusion, the established algorithm demonstrated to be an effective and valuable ancillary diagnostic approach for the sub-classification and pathologic investigation of SBCLN in daily practice.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Lymphoma, B-Cell, Marginal Zone , Lymphoma, Mantle-Cell , Waldenstrom Macroglobulinemia , Adult , B-Lymphocytes/pathology , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Lymphoma, B-Cell, Marginal Zone/genetics , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/genetics , Lymphoma, Mantle-Cell/pathology , Myeloid Differentiation Factor 88/genetics , Waldenstrom Macroglobulinemia/diagnosis , Waldenstrom Macroglobulinemia/genetics , Waldenstrom Macroglobulinemia/pathology
6.
PLoS One ; 14(11): e0223485, 2019.
Article in English | MEDLINE | ID: mdl-31682616

ABSTRACT

BACKGROUND: "Horizontal strokes should be level and vertical strokes should be straight" is a common guideline in the teaching of Chinese handwriting. Measuring deviations in level horizontal and straight vertical strokes in students' Chinese handwriting is usually assessed manually. However, this task is time-consuming and may have inconsistent outcomes when judged by different people. In this paper, we aim to formulate a method to automatically evaluate the tilt and slant degrees of students' Chinese handwriting using digital handwriting tablets. Furthermore, we analyze the relationship between the tilt and slant features of students' Chinese handwriting and other demographic and handwriting features. METHODS: Five hundred and ninety-one primary school students from grades 1 to 6 were recruited in Hong Kong. Before the assessment, a grid paper was attached to a digital handwriting tablet. The participants were then asked to copy 90 Chinese characters from a template to the grid paper. Their handwriting processes were recorded as two-dimensional points and then analyzed. The tilt and slant of the students' handwriting were calculated based on the inclination level of their horizontal and vertical strokes. Linear regressions between slant/tilt degree of the manuscripts and other handwriting features were performed. The students' demographic information was also explored. RESULTS: Slant was found to be significantly correlated to Gender (p < 0.001) and tilt×standard deviation of pen pressure (p < 0.001). Tilt was found to be significantly correlated to ground time (p < 0.001), slant (p < 0.001) and slant×special education need (p = 0.021). CONCLUSIONS: Our results demonstrate the relationship between slant, tilt and Chinese handwriting performance in primary school children. Slant and tilt can be adopted as an indicator in students' special education need diagnosis, as tilt level in the students' Chinese handwriting was related to ground time and slant× special education need, while slant is related to tilt×standard deviation of pen pressure and female students. These findings may also inspire ways to increase special education need students' writing speed.


Subject(s)
Motor Skills/physiology , Psychomotor Performance/physiology , Asian People , Child , Computers , Female , Handwriting , Hong Kong , Humans , Male , Schools , Students
7.
Neuron ; 102(3): 653-667.e6, 2019 05 08.
Article in English | MEDLINE | ID: mdl-30879785

ABSTRACT

SIM1-expressing paraventricular hypothalamus (PVH) neurons are key regulators of energy balance. Within the PVHSIM1 population, melanocortin-4 receptor-expressing (PVHMC4R) neurons are known to regulate satiety and bodyweight, yet they account for only half of PVHSIM1 neuron-mediated regulation. Here we report that PVH prodynorphin-expressing (PVHPDYN) neurons, which notably lack MC4Rs, function independently and additively with PVHMC4R neurons to account for the totality of PVHSIM1 neuron-mediated satiety. Moreover, PVHPDYN neurons are necessary for prevention of obesity in an independent but equipotent manner to PVHMC4R neurons. While PVHPDYN and PVHMC4R neurons both project to the parabrachial complex (PB), they synaptically engage distinct efferent nodes, the pre-locus coeruleus (pLC), and central lateral parabrachial nucleus (cLPBN), respectively. PB-projecting PVHPDYN neurons, like PVHMC4R neurons, receive input from interoceptive ARCAgRP neurons, respond to caloric state, and are sufficient and necessary to control food intake. This expands the CNS satiety circuitry to include two non-overlapping PVH to hindbrain circuits.


Subject(s)
Feeding Behavior/physiology , Neurons/cytology , Obesity/physiopathology , Paraventricular Hypothalamic Nucleus/cytology , Satiety Response/physiology , Agouti-Related Protein/metabolism , Animals , Arcuate Nucleus of Hypothalamus/cytology , Arcuate Nucleus of Hypothalamus/metabolism , Arcuate Nucleus of Hypothalamus/physiology , Basic Helix-Loop-Helix Transcription Factors/metabolism , Energy Metabolism , Enkephalins/metabolism , Locus Coeruleus/cytology , Locus Coeruleus/metabolism , Locus Coeruleus/physiology , Mice , Neurons/metabolism , Neurons/physiology , Parabrachial Nucleus/cytology , Parabrachial Nucleus/metabolism , Parabrachial Nucleus/physiology , Paraventricular Hypothalamic Nucleus/metabolism , Paraventricular Hypothalamic Nucleus/physiology , Protein Precursors/metabolism , Receptor, Melanocortin, Type 4/metabolism , Repressor Proteins/metabolism
8.
Neuron ; 96(1): 190-206.e7, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28957668

ABSTRACT

Sodium deficiency increases angiotensin II (ATII) and aldosterone, which synergistically stimulate sodium retention and consumption. Recently, ATII-responsive neurons in the subfornical organ (SFO) and aldosterone-sensitive neurons in the nucleus of the solitary tract (NTSHSD2 neurons) were shown to drive sodium appetite. Here we investigate the basis for NTSHSD2 neuron activation, identify the circuit by which NTSHSD2 neurons drive appetite, and uncover an interaction between the NTSHSD2 circuit and ATII signaling. NTSHSD2 neurons respond to sodium deficiency with spontaneous pacemaker-like activity-the consequence of "cardiac" HCN and Nav1.5 channels. Remarkably, NTSHSD2 neurons are necessary for sodium appetite, and with concurrent ATII signaling their activity is sufficient to produce rapid consumption. Importantly, NTSHSD2 neurons stimulate appetite via projections to the vlBNST, which is also the effector site for ATII-responsive SFO neurons. The interaction between angiotensin signaling and NTSHSD2 neurons provides a neuronal context for the long-standing "synergy hypothesis" of sodium appetite regulation.


Subject(s)
Aldosterone/physiology , Angiotensin II/physiology , Biological Clocks/physiology , Neurons/physiology , Signal Transduction , Sodium/physiology , Solitary Nucleus/physiology , Animals , Eating/physiology , Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels/physiology , Male , Mice , Mice, Transgenic , NAV1.5 Voltage-Gated Sodium Channel/physiology , Neural Pathways/physiology , Septal Nuclei/physiology , Sodium/deficiency
9.
Nat Neurosci ; 19(12): 1628-1635, 2016 12.
Article in English | MEDLINE | ID: mdl-27643429

ABSTRACT

Agouti-related peptide (AgRP) neurons of the arcuate nucleus of the hypothalamus (ARC) promote homeostatic feeding at times of caloric insufficiency, yet they are rapidly suppressed by food-related sensory cues before ingestion. Here we identify a highly selective inhibitory afferent to AgRP neurons that serves as a neural determinant of this rapid modulation. Specifically, GABAergic projections arising from the ventral compartment of the dorsomedial nucleus of the hypothalamus (vDMH) contribute to the preconsummatory modulation of ARCAgRP neurons. In a manner reciprocal to ARCAgRP neurons, ARC-projecting leptin receptor-expressing GABAergic vDMH neurons exhibit rapid activation upon availability of food that additionally reflects the relative value of the food. Thus, leptin receptor-expressing GABAergic vDMH neurons form part of the sensory network that relays real-time information about the nature and availability of food to dynamically modulate ARCAgRP neuron activity and feeding behavior.


Subject(s)
Agouti-Related Protein/metabolism , Arcuate Nucleus of Hypothalamus/metabolism , GABAergic Neurons/metabolism , Animals , Feeding Behavior , Mice , Neuropeptide Y/metabolism , Receptors, Leptin/metabolism , Sensation/physiology
10.
Nat Protoc ; 6(9): 1453-70, 2011 Sep 01.
Article in English | MEDLINE | ID: mdl-21886108

ABSTRACT

Brain stimulation methods are indispensable to the study of brain function. They have also proven effective for treating some neurological disorders. Historically used for medical imaging, ultrasound (US) has recently been shown to be capable of noninvasively stimulating brain activity. Here we provide a general protocol for the stimulation of intact mouse brain circuits using transcranial US, and, using a traditional mouse model of epilepsy, we describe how to use transcranial US to disrupt electrographic seizure activity. The advantages of US for brain stimulation are that it does not necessitate surgery or genetic alteration, but it confers spatial resolutions superior to other noninvasive methods such as transcranial magnetic stimulation. With a basic working knowledge of electrophysiology, and after an initial setup, ultrasonic neuromodulation (UNMOD) can be implemented in less than 1 h. Using the general protocol that we describe, UNMOD can be readily adapted to support a broad range of studies on brain circuit function and dysfunction.


Subject(s)
Brain Mapping/methods , Ultrasonography, Doppler, Transcranial/methods , Animals , Brain/physiology , Electrophysiology , Female , Male , Mice , Mice, Inbred C57BL
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