Publications by authors named "Lubetzki J"

Two decades after its introduction, optogenetics - a biological technique to control the activity of neurons or other cell types with light - remains a cutting edge and promising tool to study biological processes. Its increasing usage in research varies widely from causally exploring biological mechanisms and neural computations, to neurostimulation and sensory restauration. To stimulate neurons in the brain, a variety of approaches have been developed to generate precise spatiotemporal light patterns.

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Remote and precisely controlled activation of the brain is a fundamental challenge in the development of brain-machine interfaces for neurological treatments. Low-frequency ultrasound stimulation can be used to modulate neuronal activity deep in the brain, especially after expressing ultrasound-sensitive proteins. But so far, no study has described an ultrasound-mediated activation strategy whose spatiotemporal resolution and acoustic intensity are compatible with the mandatory needs of brain-machine interfaces, particularly for visual restoration.

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Relationships between glycaemic control, hypertension, and development of microangiopathy have been well documented in Type 1 (insulin-dependent) but not in Type 2 (non-insulin-dependent) diabetes mellitus. Therefore, we have investigated these relationships in a cohort of 64 Type 2 patients free of retinopathy (by angiofluorography), who were regularly followed until development of retinopathy or for at least 7 years as outpatients. Glycaemic control was assessed by 1 to 4 HbA1 determinations per year.

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In addition to their initially recognized antiviral activity, interferons are known to have a number of effects on the immune system. The role of alpha-interferon (alpha-IFN) has been evaluated in 8 studies, including 573 patients, aimed at determining the prevalence, clinical course and predictive factors of autoimmune dysthyroidism in patients treated with alpha-IFN. Two major categories of patients were treated with alpha-IFN: those with cancer and those with chronic viral hepatitis.

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Objective: Animal studies suggest that hyperlipidemia may play a direct role in glomerular damage. In patients with non-insulin-dependent diabetes mellitus (NIDDM), dyslipidemia occurs early in the course of nephropathy and may be involved in the progression of renal disease.

Cases: We report on two young NIDDM patients with marked hyperlipidemia and proteinuria, in whom renal biopsy demonstrated nondiabetic glomerulopathy.

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Among high density lipoprotein particles, LpAI particles which contain apolipoprotein A1 alone, appear to be involved in cholesterol transport from peripheral tissues to the liver. The aim of this cross-sectional study was to examine serum LpAI particle concentrations in Type 1 and Type 2 diabetic patients with renal lesions of differing grades, in comparison with normal controls and with nondiabetic patients presenting with chronic renal failure. LpAI concentrations and LpAI-to-apo A1 ratios were increased in Type 1 diabetic patients with normal albumin excretion.

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We investigated the potential pituitary origin of gonadal insufficiency in hemochromatosis. Gonadotropin secretion was studied in seven patients with hemochromatosis and hypogonadism, before and after chronic pulsatile GnRH therapy. Pulsatile LH secretion was studied before (sampling every 10 min for 6 h) and after 15-30 days of chronic pulsatile GnRH therapy (10-12 micrograms per pulse).

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We report on eight patients with diabetic thoracoabdominal neuropathy in whom careful evaluation of peripheral and autonomic nervous system function was performed. All patients had non insulin-dependent diabetes mellitus of 10.5 +/- 6.

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Hypertriglyceridemia is the most frequent modification of lipid metabolism observed in acromegaly. The somatostatin analog, octreotide (Sandostatin), widely used in the treatment of acromegaly, is able to produce a decrease in levels of growth hormone (GH), insulin, and Insulin-like Growth Factor 1 (IGF1). We have attempted to evaluate the influence of this treatment on the lipid status of acromegalic patients.

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Objective: To examine the distribution of Lp(a) plasma levels in patients with IDDM and NIDDM, and in nondiabetic and IDDM patients with chronic renal failure.

Research Design And Methods: Cross-sectional study of Lp(a) plasma levels in a population of diabetic patients with stable metabolic control, with simultaneous determination of plasma lipids, fasting plasma glucose, and HbA1. Thirty-six patients with IDDM, 90 with NIDDM, and 41 with chronic renal failure (20 IDDM, 21 nondiabetic) were compared with 78 control subjects.

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This study was designed to evaluate the involvement of airways innervation during diabetic autonomic neuropathy. Bronchial response to methacholine was assessed by inhalation of serially doubling doses in 22 insulin-dependent diabetes mellitus (IDDM) patients and 11 nondiabetic control subjects selected for their nonsmoking habits. Cardiovascular autonomic control was studied by four standardized tests, i.

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Bromocriptine is currently and successfully used for the treatment of pituitary prolactinomas. However, bromocriptine appears unable to normalize plasma prolactin levels in about 10% and to reduce tumour size in one-third of cases. The lack of normalization of plasma prolactin levels in spite of a daily dose of bromocriptine equal to or higher than 15 mg suggests a bromocriptine resistance.

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Objective: To determine the cardiovascular effects of the somatostatin analog octreotide in patients with acromegaly.

Design: Prospective nonrandomized study.

Setting: Referral-based endocrinology clinic.

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Pyoderma gangrenosum is a rare chronic and recurrent skin disease characterized by progressing lesions from papulopustules to large necrotic sterile ulcers. Its definite etiology remains unknown. In a 40-year-old woman with typical pyoderma gangrenosum an intrasellar mass with suprasellar extension was diagnosed and removed by transsphenoidal surgery.

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Total glycosylated hemoglobin (HbA1) and fructosamine were evaluated as screening tools for detection of glucose-tolerance abnormalities in 144 asymptomatic subjects undergoing a 75-g oral glucose tolerance test. Subjects were classified according to World Health Organization criteria as having normal (n = 78), impaired (n = 40), or diabetic (n = 26) glucose tolerance. We found good specificity for HbA1 and fructosamine (100 and 97%, respectively) but low sensitivity (15 and 19%, respectively).

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We studied papillary muscle mechanics and energetics, myosin phenotype, and ATPase activities in left ventricles from rats bearing a growth hormone (GH)--secreting tumor. 18 wk after tumor induction, animals exhibited a dramatic increase in body weight (+101% vs. controls) but no change in the ventricular weight/body weight ratio.

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Fasting and postprandial (or post-glucose load) plasma glucose, total HbA1 and fructosamine (F) were simultaneously assessed in 371 diabetic patients (125 insulin dependent and 246 non-insulin dependent) and in 122 nondiabetic subjects, (98 with normal glucose tolerance and 24 with impaired glucose tolerance). Fructosamine yielded nearly similar information as HbA1 about glycemic control, since similar relationships were observed between plasma glucose values and HbA1 or fructosamine levels in the different groups. A longitudinal study performed during a three-month follow-up in 74 diabetic patients and extended to six months in 19 of them, without any modification of treatment, indicated that reproducibility of HbA1 and fructosamine was nearly the same with a slight advantage for HbA1.

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In acromegaly the plasma volume is chronically elevated and it returns to normal when the disease is successfully treated. To define the role of ANF in such a chronic disorder of extracellular fluid volume homeostasis the plasma level was assayed in 37 acromegalic patients with active or inactive (successfully treated) disease. Five patients were studied before and after therapy.

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The production of thymulin by the thymic epithelium is under complex control involving the endocrine system. Experimental models have suggested that prolactin (PRL) and growth hormone (GH) participate in this regulation but this has not been documented in humans. Using a bioassay we measured circulating thymulin levels in patients with hyperprolactinemia (n = 21), acromegaly (n = 15), or both (n = 6).

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