Localization of beta-andrenoceptors in the anterior segment of the albino rabbit eye using a fluorescent analog of propranolol.

A fluorescent analog of propranolol, 9-amino-acridin-propranolol (9-AAP), was injected into the carotid arteries of albino rabbits in an attempt to localize β-adrenergic receptors (β-adrenoceptors) in the anterior segment of the eye. 9-AAP fluorescence was noted mainly in the ciliary epithelium, but also in the walls of the episcleral vessels. Only mild fluorescence was noted in the iris sphincter region. It is suggested that these findings are compatible with the distribution of β-receptor sites in the anterior segment of the rabbit eye.     

Profound hypothermia protects neurons and astrocytes, and preserves cognitive functions in a Swine model of lethal hemorrhage

BACKGROUND: Lethal injuries can be repaired under asanguineous hypothermic arrest (suspended animation) with excellent survival. This experiment was designed to test the impact of this strategy on neuronal and astroglial damage in a swine model of lethal hemorrhage. Furthermore, our goal was to correlate the histological changes in the brain with neurological outcome, and the levels of circulating brain specific markers. MATERIALS AND METHODS: Uncontrolled hemorrhage was induced in 32 female swine (80-120 lbs) by creating an iliac artery and vein injury, followed 30 min later by laceration of the thoracic aorta. Through a thoracotomy approach, organ preservation fluid was infused into the aorta using a roller pump. Experimental groups included normothermic controls (no cooling, NC), and groups where hypothermia was induced at three different rates: 0.5 degrees C/min (slow, SC), 1 degrees C/min (medium, MC), or 2 degrees C/min (fast, FC). Profound hypothermia (core temperature of 10 degrees C) was maintained for 60 min for repair of vascular injuries, after which the animals were re-warmed (0.5 degrees C/min) and resuscitated on cardiopulmonary bypass (CPB). Circulating levels of neuron specific enolase (NSE) and S-100beta were serially measured as markers of damage to neurons and astrocytes, respectively. Light microscopy and quantitative immunohistochemical techniques were used to evaluate hippocampal CA1 area and caudate putamen for neuronal injury and astrogliosis (astrocyte hyperplasia/hypertrophy). Surviving animals were observed for 6 weeks and neurological status was documented on an objective scale, and cognitive functions were evaluated using a technique based upon the concept of operant conditioning. RESULTS: Normothermic arrest resulted in clinical brain death in all of the animals. None of the surviving hypothermic animals displayed any neurological deficits or cognitive impairment. On histological examination, normothermic animals were found to have ischemic changes in the neurons and astrocytes (hypertrophy). In contrast, all of the hypothermic animals had histologically normal brains. The circulating levels of brain specific proteins did not correlate with the degree of brain damage. The changes in NSE levels were not statistically significant, whereas S-100beta increased in the circulation after CPB, largely independent of the temperature modulation. CONCLUSIONS: Profound hypothermia can preserve viability of neurons and astrocytes during prolonged periods of cerebral hypoxia. This approach is associated with excellent cognitive and neurological outcome following severe shock. Circulating markers of central nervous system injury did not correlate with the actual degree of brain damage in this model.     

Alpha-fetoprotein expression is a potential prognostic marker in hepatocellular carcinoma

AIM: To characterize the alpha-fetoprotein (AFP) positive and negative hepatocellular carcinoma (HCC) samples. METHODS: Thirty-seven paraffin-embedded human HCC samples were analyzed by immunohistochemistry for the following antigens: AFP, β-catenin, p53, CD44, MSH-2, MLH-1, and HNF-4. The tumors were divided into two groups based on the AFP expression. The immunophenotypic data and important clinical parameters were studied between the two groups. RESULTS: Twenty-one of the thirty-seven examined HCCs were AFP positive. Seven with nuclear p53 staining were AFP positive, while seven tumors with nuclear β-catenin staining were AFP negative. CD44 staining and high histological tumor grade were more frequent among the AFP-positive HCCs. The other immunophenotypical and dinical parameters did not show statistically significant difference in their distribution between the AFP positive and negative samples. CONCLUSION: AFP expression in HCC correlates with unfavorable prognostic factors, while nuclear β-catenin positivity is more common among the AFP-negative liver tumors. This observation supports the microarray data on in vivo human tumors.     

Effects of drug serum of anti-fibrosis I herbal compound on calcium in hepatic stellate cell and its molecular mechanism

AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fibrosis and portal hypertension. METHODS: The activated HSC line was plated on small glass cover slips in 24 wells culture dishes at a density of 5×106 /mL, and incubated in RPMI-1640 media for 24 h. After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured with laser scanning confocal microscopy (LSCM). The dynamic changes of intracellular Ca2+, stimulated by carbon tetrachloride, TGF-β1 antibody and the drug serum of anti-fibrosis I herbal compound and under orthogonal design were determined by LSCM. The effect of anti-fibrosis I herbal compound on intracellular Ca2+ was observed before and after the addition of TGF-β1 antibody. RESULTS: The intracellular Ca2+ were significantly different in different dosage of carbon tetrachloride anti-fibrosis I formula drug serum, TGF-β1 antibody and different turn of these substance, but their interval time between CCl4 and TGF-β1 antibody, CCl4 and anti-fibrosis I drug serum had no influence on intracellular Ca2+. The result showed intracellular Ca2+ wasn't significantly different between rat serum without anti-fibrosis I and untreated group. After carbon tetrachloride stimulation, intracellular Ca2+ of activated HSC increased significantly when the dosage of CCl4 from 5 to 15 mmol/L, however, decreased significantly after stimulation by 5-20 μg/mL TGF-β1 antibody or 5-20 mL/L drug serum. Moreover, before and after the addition of TGF-β1 antibody, intracellular Ca2+ was significantly different. These results suggested that the molecular mechanism was independent of blocking TGF-β1 effects. CONCLUSION: Anti-fibrosis I herbal compound may treat hepatic fibrosis and decrease portal hypertension by inhibiting activated HSC contractility through decrease of intracellular Ca2+.     

Role of transforming growth factor-β2 in, and apossible transforming growth factor-β2 gene polymorphism as a marker of, renal dysfunction in essential hypertension: A study in Turkish patients

Background:

Many studies have shown that transforming growth factor(TGF)-β has a major role in renal scarring in many renal diseases and hypertension.

Objectives:

The primary aim of this study was to investigate both the relationship between hypertension and serum and urinary levels of TGF-β₂ (a more sensitive isoform for glomeruli than TGF-β₁), and the effects of combination therapy with perindopril + indapamide on microalbuminuria, which becomes an early indicator of hypertensive benign nephropathy, and serum and urinary TGF-β₂ levels in patients with mild to moderate essential hypertension. In addition, we examined the possible relationship between TGF-β₂ gene polymorphism and essential hypertension.

Methods:

This study was conducted at the Department of Nephrology, Medical Faculty, Gazi University, Ankara, Turkey. Patients aged ≥18 years with newly diagnosed mild to moderate essential hypertension (systolic/diastolic blood pressure [SBP/DBP] >120/>80 mm Hg) who had not previously received antihypertensive treatment were included in the study. Patients with stage I hypertension received perindopril 2 mg + indapamide 0.625 mg (tablet), and patients with stage lI hypertension received perindopril 4 mg + indapamide 1.125 mg (tablet). All study drugs were given OD (morning) PO with food for 6 months. Serum and urinary TGF-β₂ and creatinine levels and serum and urinary albumin levels were measured before and after perindopril + indapamide administration. Amplified DNA fragments of the TGF-β₂ primer region were screened using amplification refractory mutation system polymerase chain reaction analysis, and the number of ACA repeats was confirmed by DNA sequencing. Genetic studies were performed using a commercial TGF-β₂ kit.

Results:

Forty patients were enrolled in the study, and 38 patients (27 women, 11 men; mean [SD] age, 46.3 [6.5] years) completed it. SBP and DBP were significantly decreased from baseline with perindopril/indapamide (both, P < 0.001). Microalbuminuria and urinary TGF-β₂ levels also decreased significantly from baseline (P = 0.04 and P < 0.001, respectively), whereas the serum TGF-β₂ level did not change significantly. Three patients, all of whom were found to have TGF-β₂ gene mutations, had increased urinary TGF-β₂ levels despite good blood pressure control.

Conclusions:

The results of this study in patients with mild to moderate hypertension suggest that, despite good clinical control of blood pressure, the persistence of microalbuminuria and high urinary TGF-β₂ levels might predict renal impairment. When treating these patients, genetic tendencies and possible polymorphisms on the TGF-β₂ locus should be kept in mind.     

The effect of intracerebroventricularly administered dibutyryl adenosine 3',5'-cyclic monophosphate on cerebrospinal fluid and serum dopamine-beta-hydroxylase in rabbits

Intracerebrospinal injected or infused dibutyryl adenosine 3′,5′-cyclic monophosphate provoked (a) an initial small decrease of cerebrospinal fluid dopamine-β-hydroxylase activity which lasted for 2 hours, followed by a significant rise of a 4–6 hours duration, together with a rise in total cerebrospinal fluid protein concentration, (b) a significant increase in serum dopamine-β-hydroxylase activity. Pretreatment of rabbits with two intracisternal injections of 6-hydroxydopamine completely abolished the dibutyryl adenosine 3′,5′-cyclic monophosphate induced release of dopamine-β-hydroxylase in the cerebrospinal fluid but only partially the release of dopamine-β-hydroxylase in the serum.     

Beta-adrenergic regulation of Sertoli cell adenylyl cyclase: desensitization by homologous hormone

Incubation of Sertoli cell-enriched cultures with D,L-isoproterenol caused a time- and concentration-dependent, homologous desensitization of isoproterenol-responsive adenyl cyclase, whereas the response to FSH was unaffected. Half-maximal desensitization was achieved within 1 h of preincubation, after which a more gradual loss of response was observed. Preincubation of Sertoli cells for 24 h with increasing concentrations of D,L-isoproterenol demonstrated that the concentration required to obtain half-maximal densensitization was approximately 10-fold lower than the Km for activation of adenylyl cyclase. The function of the guanine nucleotide regulatory component (N-component) of the adenylyl cyclase complex in hormonally desensitized Sertoli cells, as evaluated by activation of adenylyl cyclase by GTP, GMPP(NH)P, fluoride and Mg2+, was not affected by the hormone pretreatment. Preincubation of Sertoli cells with a high concentration of dbcAMP (10(-3) M) for 24 h was associated with a 45% reduction in adenylyl cyclase activation by both FSH and isoproterenol. Also in this case fluoride- and GTP-stimulated adenylyl cyclase activities were normal. However, the effects of dibutyryl cyclic AMP occurred much more slowly than agonist-induced desensitization, indicating that cAMP may not be the primary mediator of homologous desensitization of Sertoli cell adenylyl cyclase by isoproterenol.     

Regional changes in the activities of aminergic biosynthetic enzymes in the brains of hypertensive rats.

The activities of monoamine biosynthetic enzymes were measured in brain regions of several hypertensive rat models at various ages. The types of hypertensive rats were the spontaneously hypertensive rat (SHR) and a stroke-prone substrain of the SHR as well as DOCA-salt and renal hypertensive rats. The genetically hypertensive rats had significantly elevated blood pressures as compared to the Wistar-Kyoto control rat after 5 weeks of age. During the early development of hypertension in the SHR, the activities of tyrosine hydroxylase in the hypothalamus and corpus striatum and of dopamine-beta-hydroxylase in the hypothalamus and pons-medulla were significantly higher than in the control rats. Tryptophan-hydroxylase was also elevated in the hypothalamus in SHR. From 3 to 8 weeks of age there appeared to be a significant correlation between hypothalamic dopamine-beta-hydroxylase activity and blood pressure in the hypertensive rats. In contrast, the activities of tyrosine hydroxylase and dopamine-beta-hydroxylase were slightly decreased in the DOCA-salt and renal hypertensive rats. It is suggested that noradrenergic or adrenergic neurons in the hypothalamus may participate in the initiation of elevated blood pressure in the genetic, but not in the DOCA-salt or renal hypertensive rats.     

β-内酰胺族抗菌素的研究——Ⅲ.7-脒硫乙酰胺基头孢菌素酸亚砜衍生物的立体定向合成

为寻找更有效的新头孢菌素衍生物,本文报道了具脒硫基侧链的头孢菌素酸(R)和(S)型亚砜的立体定向合成。(S)-型亚砜衍生物II-(S)系将化合物V直接用过酸氧化,再与各种取代硫脲缩合而得。若将7-ACA转化为Schiff碱再行氧化则可立体定向地合成(R)-型亚砜Ⅶ,继而水解,酰化得Ⅸ。最后与各种取代硫脲缩合可得(R)-亚砜衍生物Ⅱ-(R)。所得各中间体及产物的立体化学均经₁H核磁共振予以证实。