Anatomy and histology of the transverse humeral ligament.

The classic literature describes the transverse humeral ligament (THL) as a distinct anatomic structure with a role in biceps tendon stability; however, recent literature suggests that it is not a distinct anatomic structure. The purpose of this study was to evaluate the gross and microscopic anatomy of the THL, including a specific investigation of the histology of this ligament. Thirty frozen, embalmed cadaveric specimens were dissected to determine the gross anatomy of the THL.

IFN-γ signaling to astrocytes protects from autoimmune mediated neurological disability.

Demyelination and axonal degeneration are determinants of progressive neurological disability in patients with multiple sclerosis (MS). Cells resident within the central nervous system (CNS) are active participants in development, progression and subsequent control of autoimmune disease; however, their individual contributions are not well understood. Astrocytes, the most abundant CNS cell type, are highly sensitive to environmental cues and are implicated in both detrimental and protective outcomes during autoimmune demyelination.

Role of differentiation of liver sinusoidal endothelial cells in progression and regression of hepatic fibrosis in rats.

Background & Aims: Capillarization, characterized by loss of differentiation of liver sinusoidal endothelial cells (LSECs), precedes the onset of hepatic fibrosis. We investigated whether restoration of LSEC differentiation would normalize crosstalk with activated hepatic stellate cells (HSC) and thereby promote quiescence of HSC and regression of fibrosis.

Methods: Rat LSECs were cultured with inhibitors and/or agonists and examined by scanning electron microscopy for fenestrae in sieve plates.

Prevention of hepatic fibrosis in a murine model of metabolic syndrome with nonalcoholic steatohepatitis.

The endocannabinoid pathway plays an important role in the regulation of appetite and body weight, hepatic lipid metabolism, and fibrosis. Blockade of the endocannabinoid receptor CB1 with SR141716 promotes weight loss, reduces hepatocyte fatty acid synthesis, and is antifibrotic. D-4F, an apolipoprotein A-1 mimetic with antioxidant properties, is currently in clinical trials for the treatment of atherosclerosis.

Review of meningioma histopathology.

The histological appearance of a meningioma is an important predictor of tumor behavior and is frequently a factor in decisions concerning therapy. The relationship between histological features and prognosis is formalized in grading schemes such as those published by the World Health Organization (WHO), most recently in 2007. Although the latest edition is an improvement over previous grading schemes, the WHO scheme still fails to fully address a variety of important issues regarding the relationship between meningioma histological characteristics and behavior.

Telomerase and markers of cellular proliferation are associated with the progression of cervical intraepithelial neoplasia lesions.

The expression of the catalytic subunit of telomerase protein (human telomerase reverse transcriptase [hTERT]), which is associated with telomerase activity, was evaluated as a potential marker of the high-grade premalignant cervical intraepithelial neoplasia (CIN 2/3) lesions. For comparison, cases of normal cervical squamous mucosa, low-grade CIN1 lesion, and cervical squamous cell carcinoma were included. The hTERT expression was also compared with Ki-67 and topoisomerase II-alpha (TPII-alpha) to determine the proliferative activity of the hTERT-positive dysplastic cells by a quantitative immunohistochemical staining method and was classified as follows: negative, 5% or less; moderate, 6% to 50%; or high, greater than 50% of the positive cells.

Liver X receptor activation decreases the severity of experimental autoimmune encephalomyelitis.

Agonists of liver X receptors (LXR), members of the nuclear hormone receptor superfamily, alter secretion of proinflammatory cytokines, suggesting potential antiinflammatory effects. A synthetic LXR agonist inhibited T-cell proliferation and cytokine release in a dose-dependent manner. Treatment of mice during induction of experimental autoimmune encephalomyelitis reduced clinical symptoms, central nervous system cellular inflammation, and major histocompatibility class II expression on microglia, as well as demyelination.

CNS viral infection diverts homing of antibody-secreting cells from lymphoid organs to the CNS.

Neurotropic coronavirus infection of mice results in acute encephalomyelitis followed by viral persistence. Whereas cellular immunity controls acute infection, humoral immunity regulates central nervous system (CNS) persistence. Maintenance of serum Ab was correlated with tissue distribution of virus-specific Ab-secreting cells (ASC).

Astrocyte expression of a dominant-negative interferon-gamma receptor.

Interferon-gamma (IFN-gamma) is a major proinflammatory cytokine, and binding to its nearly ubiquitous receptor induces a wide variety of biological functions. To explore the role(s) of IFN-gamma signaling in astrocytes, transgenic mice (GFAP/IFN-gammaR1DeltaIC) expressing a dominant-negative IFN-gamma receptor alpha chain under control of the astrocyte-specific glial fibrillary acid protein (GFAP) promoter were generated. Transgenic mice developed normally, had normal astrocyte numbers and distribution, and exhibited no clinically overt phenotype.

The peroxisome proliferator-activated receptor gamma ligand rosiglitazone delays the onset of inflammatory bowel disease in mice with interleukin 10 deficiency.

Aims: To test whether the peroxisome proliferator-activated receptor gamma (PPARgamma) ligand rosiglitazone (Ro) has therapeutic activity in the IL-10(-/-) mouse model of inflammatory bowel disease (IBD), and to identify the cellular targets and molecular mechanisms of Ro action.

Methods: The progression of spontaneous chronic colitis in IL-10(-/-) mice was compared in 5-week-old mice fed a standard diet with or without Ro for 12 weeks. The possible therapeutic effect of Ro was also tested over a 6-week interval in older IL-10(-/-) mice with established IBD.

Mechanisms of central nervous system viral persistence: the critical role of antibody and B cells.

Contributions of humoral and cellular immunity in controlling neurotropic mouse hepatitis virus persistence within the CNS were determined in B cell-deficient J(H)D and syngeneic H-2(d) B cell+ Ab-deficient mice. Virus clearance followed similar kinetics in all mice, confirming initial control of virus replication by cellular immunity. Nevertheless, virus reemerged within the CNS of all Ab-deficient mice.