De novo expression of vascular endothelial growth factor in human pancreatic cancer: evidence for an autocrine mitogenic loop.

Background & Aims: The role of vascular endothelial growth factor (VEGF) and its receptors in tumor angiogenesis has been well established. We analyzed the expression pattern and biologic significance of VEGF and its receptors in human pancreatic cancer.

Methods: VEGF, KDR/flk-1, and flt-1 expression were examined by immunohistochemistry, in situ hybridization, reverse-transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and receptor phosphorylation.

Joubert syndrome: monozygotic twins with discordant phenotypes.

We describe three sisters with Joubert syndrome, two of whom are monozygotic twins with highly discordant phenotypes. The twins were born at 34 weeks' gestation with discordant birthweights. Their anatomic, neurologic, and developmental status differs greatly: Twin B is able to walk, run, and is verbal, unlike Twin A who is wheelchair-bound, severely retarded, nonverbal, and autistic.

Cyclin D- and E-dependent kinases and the p57(KIP2) inhibitor: cooperative interactions in vivo.

This study examines in vivo the role and functional interrelationships of components regulating exit from the G1 resting phase into the DNA synthetic (S) phase of the cell cycle. Our approach made use of several key experimental attributes of the developing mouse lens, namely its strong dependence on pRb in maintenance of the postmitotic state, the down-regulation of cyclins D and E and up-regulation of the p57(KIP2) inhibitor in the postmitotic lens fiber cell compartment, and the ability to target transgene expression to this compartment. These attributes provide an ideal in vivo context in which to examine the consequences of forced cyclin expression and/or of loss of p57(KIP2) inhibitor function in a cellular compartment that permits an accurate quantitation of cellular proliferation and apoptosis rates in situ.

Asymptomatic optic disc edema.

Non-arteritic anterior ischemic optic neuropathy (AION-na) classically presents with visual loss, altitudinal visual field defects, and optic nerve swelling. AION-na presumably occurs secondary to an ischemic event. Two patients are described who were at risk for developing AION-na.

Luxury perfusion following anterior ischemic optic neuropathy.

We present five patients who developed luxury perfusion following anterior ischemic optic neuropathy in whom fluorescein angiography was misinterpreted as "capillary hemangioma" or neovascularization of the disc. In each case, the segment of disc hyperemia corresponded to a spared region of visual field. Luxury perfusion represents a reparative autoregulatory reaction to ischemia.

Receptor-independent G protein activation may account for the stimulatory effects of first-generation H1-receptor antagonists in HL-60 cells, basophils, and mast cells.

The first-generation histamine H1-receptor antagonists, chlorpheniramine (CPHE) and diphenhydramine (DPH), may activate histamine release from basophils and mast cells. Because CPHE and DPH are cationic-amphiphilic and because several substances with such physicochemical properties activate heterotrimeric regulatory guanine nucleotide-binding proteins (G-proteins) in a receptor-independent manner, we asked the question of whether or not H1-receptor antagonists could be G-protein activators as well. In dibutyryl cAMP-differentiated HL-60 cells, CPHE and DPH increased cytosolic Ca2+ concentration and azurophilic granule release in pertussis toxin (PTX)-sensitive manners.

Stimulation of histamine H2- (and H1)-receptors activates Ca2+ influx in all-trans-retinoic acid-differentiated HL-60 cells independently of phospholipase C or adenylyl cyclase.

In human neutrophils, histamine H2-receptors mediate activation of adenylyl cyclase (AC) and inhibition of N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-induced superoxide anion (O2-) formation, and in HL-60 promyelocytes, H2-receptors mediate parallel activation of AC, phospholipase C (PLC) and non-selective cation (NSC) channels. As all-trans-retinoic acid (RA) is successfully used in the differentiation therapy of acute promyelocytic leukaemia, we studied signal transduction in RA-differentiated HL-60 cells. Histamine and the H2-receptor agonist, impromidine, induced both rises in cAMP levels and cytosolic Ca2+ ([Ca2+]i).

Cationic-amphiphilic arpromidine-derived guanidines and a histamine trifluoromethyl-toluidide derivative may activate pertussis toxin-sensitive G-proteins by a receptor-independent mechanism.

Formyl peptides activate superoxide anion (O2-) formation in human neutrophils and in HL-60 cells via pertussis toxin (PTX)-sensitive guanine nucleotide-binding proteins (G-proteins), and histamine (HA) mediates inhibition of O2- formation via H2-receptors. We have studied the effects of lipophilic arpromidine-derived guanidines, which are potent, full H2-receptor agonists in the guinea pig atrium, on O2- formation and on activation of G-proteins in HL-60 membranes and on purified G-proteins. We have also studied the effects of a HA trifluoromethyl-toluidide derivative (HTMT), a cationic-amphiphilic HA derivative which activates O2- formation in HL-60 cells through a mechanism which is independent of known HA receptor subtypes, on G-protein activation.

Ophthalmologic examination of patients with seasonal affective disorder, before and after bright light therapy.

Purpose: We assessed the potential ocular hazards of bright light therapy for patients with seasonal affective disorder, after both short- and long-term treatment, and identified prospective patients with pre-existing ocular abnormalities.

Methods: Fifty patients with seasonal affective disorder received daily exposure to artificial light in the morning or evening for 30 minutes at an illuminance level of 10,000 lux (irradiant dose, 0.016 J/cm2).

Interleukin-2 receptor beta and CD57 expression in orbital tissues from patients with chronic, stable thyroid-associated ophthalmopathy.

In order to determine whether components of the interleukin-2 receptor (IL-2R) and lymphoid cells are present in extra ocular and periocular tissues from patients with chronic, stable thyroid-associated ophthalmopathy (TAO) we studied 16 specimens of extra ocular muscle and periorbital connective tissue from 14 patients with chronic, stable, TAO using an immunohistochemical assay and a panel of murine monoclonal antibodies reactive with IL-2R alpha and beta components and lymphoid cell surface markers. As controls we studied orbital tissues from 11 patients undergoing surgery for unrelated orbital disorders. All extra ocular muscle specimens from patients with TAO exhibited IL-2R beta expression primarily on the perimysium and endomysium surrounding the ocular muscle fasciculi and fibers of which nine specimens stained intensely.

Fascicular arrangement in partial oculomotor paresis.

We treated two patients with partial oculomotor paresis who had pupillary mydriasis, marked inferior rectus muscle weakness, and medial rectus muscle paresis, which were attributed to an ipsilateral fascicular lesion, demonstrated on neuroimaging studies. These cases support the fascicular proximity of inferior rectus muscle and pupillary fibers and suggest that fascicular medial rectus and inferior rectus muscle fibers are adjacent to each other.

Immunohistochemical evidence for C3bi involvement in Graves ophthalmopathy.

Purpose: To determine by immunohistochemical methods if components of the complement system are present in Graves ophthalmopathy extraocular and periocular tissues compared with non-Graves ophthalmopathy ocular tissues, and, if so, whether a qualitative difference exists.

Methods: Orbital muscle, periorbital muscle, and adipose tissue from 10 Graves ophthalmopathy patients were studied with in situ assays using monoclonal antibodies for C3bi and C5b-9 (the terminal attack complex) complement components. Extraocular muscle, periocular muscle, and adipose tissue from 12 patients treated for unrelated orbital disorders were used as controls.

Embolization of the ophthalmic artery for control of epistaxis: report of two cases.

Embolization of the internal maxillary artery, an accepted method for control of severe or recurrent posterior epistaxis, usually involves the ipsilateral artery, but occasionally the contralateral vessel and the facial arteries as well. Such endovascular treatment may fail if the vascular supply to the bleeding vessels originates in derivative branches of the ophthalmic artery. We report two unusual cases in which embolization of the ophthalmic artery was performed to control epistaxis.

[Pseudotumor cerebri, clinical parameters and therapeutic modalities].

Pseudotumor cerebri is a central nervous disorder with elevated intracranial pressure that is most common among young obese women. It presents with headache, transient visual obscurations and loss of central vision. Papilledema and visual field defects are frequent.

Visual recovery in two patients after intravenous methylprednisolone treatment of central retinal artery occlusion secondary to giant-cell arteritis.

Two patients with central retinal artery occlusions secondary to biopsy-proven giant-cell arteritis lost visual acuity to no light perception but recovered to baseline acuity after treatment with intravenous methylprednisolone at a dose of 15 to 30 mg/kg/day. The potential advantages and theoretical basis of early and aggressive treatment with large-dose intravenous corticosteroids in arteritic central retinal artery occlusion are discussed.