The Discovery of ( S)-1-(6-(3-((4-(1-(Cyclopropanecarbonyl)piperidin-4-yl)-2-methylphenyl)amino)-2,3-dihydro-1 H-inden-4-yl)pyridin-2-yl)-5-methyl-1 H-pyrazole-4-carboxylic Acid, a Soluble Guanylate Cyclase Activator Specifically Designed for Topical Ocular Delivery as a Therapy for Glaucoma

Soluble guanylate cyclase (sGC), the endogenous receptor for nitric oxide (NO), has been implicated in several diseases associated with oxidative stress. In a pathological oxidative environment, the heme group of sGC can be oxidized becoming unresponsive to NO leading to a loss in the ability to catalyze the production of cGMP. Recently a dysfunctional sGC/NO/cGMP pathway has been implicated in contributing to elevated intraocular pressure associated with glaucoma. Herein we describe the discovery of molecules specifically designed for topical ocular administration, which can activate oxidized sGC restoring the ability to catalyze the production of cGMP. These efforts culminated in the identification of compound (+)-23, which robustly lowers intraocular pressure in a cynomolgus model of elevated intraocular pressure over 24 h after a single topical ocular drop and has been selected for clinical evaluation.

[Atypical presentation of a carcinoid syndrome]

A 76-year-old woman presenting with right heart failure is reported. The investigation showed an ileal carcinoid tumour with multiple metastases and tricuspid regurgitation caused by a cardiac carcinoid lesion. Echocardiographic study and histopathological examination revealed typical characteristics of carcinoid heart disease. Nevertheless, except for the cardiac symptomatology, the patient did not show any other clinical manifestation of the carcinoid syndrome. Isolated right heart failure as the first sign of a carcinoid syndrome is rare; only two other cases have been described in the literature.

Clindamycin/primaquine versus trimethoprim-sulfamethoxazole as primary therapy for Pneumocystis carinii pneumonia in AIDS: a randomized, double-blind pilot trial

The aim of this double-blind pilot trial was to compare clindamycin/primaquine with trimethoprim-sulfamethoxazole (TMP-SMZ) as primary treatment for AIDS-related Pneumocystis carinii pneumonia (PCP). The focus was on toxicity and tolerability since comparisons of efficacy were limited by the small sample size. Sixty-five individuals with a first episode of possible PCP were randomly assigned to receive clindamycin/primaquine (34 patients) or TMP-SMZ (31 patients). PCP was subsequently proven microbiologically in 27 and 22 of the patients in these respective groups. Half of the participants had an arterial partial oxygen pressure at enrollment of < or = torr. The incidence and severity of adverse reactions were lower--but not significantly lower (P = .07 and .08, respectively)--with clindamycin/primaquine. The markers of severity improved in a similar manner regardless of which regimen was administered. No significant differences were documented in outcome, duration of survival, length of the PCP-free interval, or rate of relapse. The results of this pilot study show a trend toward less toxicity with clindamycin/primaquine than with TMP-SMZ. This result must be confirmed by larger-scale clinical trials, which are also needed to better compare the efficacy of the two regimens.

[Sudden death in leukemic patients treated with doxorubicin]

Cardiotoxicity of the anthracycline antineoplastic drugs is well known, especially the chronic effects, manifested mainly as congestive heart failure. Fewer reports have been published about the acute cardiotoxicity of these medications, and risk factors associated with their use. Two cases of malignant arrhythmias leading to sudden death associated with severe hypokalemia are reported. These cases suggest a synergistic effect between anthracyclines and electrolyte disorders resulting in the acute cardiotoxicity of these drugs. The administration of these antineoplastic drugs should include regular and systematic control of serum electrolytes and correction of hypokalemia during treatment.

PET imaging of cortical S2 serotonin receptors after stroke: lateralized changes and relationship to depression

Patients with right-hemisphere strokes (N = 9) more than 1 year after injury had greater cortical binding of (3-N-[11C]methyl)spiperone than a similar group of patients with left-hemisphere strokes (N = 8) or normal control subjects (N = 17). The higher S2 serotonin receptor binding occurred in uninjured regions of the right parietal and temporal cortex. The ratio of binding in the ipsilateral to contralateral cortex showed a significant negative correlation with severity of depression scores in the left temporal cortex. These findings suggest that the biochemical response of the brain may be different depending on which hemisphere is injured and that some depressions may be a consequence of the failure to upregulate serotonin receptors after stroke.

Mitotic activity of airway epithelium after short exposure to tobacco smoke and the effect of the anti-inflammatory agent phenylmethyloxadiazole

Mitotic activity of extra- and intra-pulmonary airway epithelium has been studied in male rats exposed to tobacco smoke for 1, 2, 3, 7 or 14 days, with and without addition of the anti-inflammatory agent phenylmethyloxadiazole (PMO) to the tobacco. In both control and exposed animals the mitotic index is greater in extrapulmonary regions than intrapulmonary ones. A single exposure to tobacco smoke significantly increases mitotic activity in both airway regions. This initial level of mitotic response is not maintained but is rapidly restored by 1 day free from tobacco exposure: the second peak is as high as the first. Exposure to tobacco + PMO modifies timing and amplitude of the mitotic response. The effect of PMO is somewhat paradoxical since the first peak occurs later, i.e. after 2 days of exposure, but the increase is almost twice that seen after tobacco alone. The timing of the second peak is the same as after tobacco alone, but its amplitude is only half. In each experimental group the mitogenic effect is exerted on an intact epithelium. In animals exposed to tobacco alone, or tobacco + PMO, in extrapulmonary airways mitoses are located mainly in the basal region of the epithelium, whereas in intrapulmonary airways they are located mainly at the mid or superficial level.

Lidocaine plasma concentrations during and after endoscopic procedures

Plasma lidocaine concentrations were intermittently measured in 8 upper gastrointestinal endoscopy and 12 bronchoscopy patients. The highest individual concentration was 0.98 microgram/ml in the upper gastrointestinal endoscopy patients and 3.79 microgram/ml in the bronchoscopy patients. Highest concentrations were reached at 15 minutes in the gastrointestinal endoscopy patients and at 30 or 60 minutes in the bronchoscopy patients. Thus, since lidocaine does not produce toxic effects at concentrations inferior to 6 microgram/ml, doses of this topical anaesthetic up to 16 mg/kg can be safely given during endoscopic procedures to patients with normal hepatic and cardiovascular functions. However, patients with liver metastases should be considered at high risk even if their liver function tests are normal. Patients at high risk of developing lidocaine toxicity should receive lower doses and be closely watched for at least 60 minutes after the end of the procedure.

The effect of isoprenaline and pilocarpine on mitotic index and goblet cell number in rat respiratory epithelium

The effect of both isoprenaline (IPN) and pilocarpine (PCP) on mitotic activity and goblet cell number has been studied at 5 levels of the bronchial tree in male and female animals. While both drugs increased mitotic index and goblet cell number at most of the airway levels studied, differences in their effect were detected. After both drugs, nuclei in division were more often superficial within the epithelium than basal but IPN caused a greater increase in mitotic index than PCP. IPN increased goblet cell number at all levels, PCP only in the trachea and larger intrapulmonary airways. The types of goblet cell increased by IPN were particularly those containing acid glycoprotein, whereas PCP increased all types of goblet cell, that is, both those containing neutral and acid glycoprotein. After the drugs, the concentration of cells per unit length of airway epithelium was higher than normal. This is the first study demonstrating the effect of these two drugs on both goblet cell number and cell division. While the two drugs differ in their pharmacological action, the result of their stimulation of airway epithelium is similar. The way in which each effect is produced is discussed.

Goblet cell glycoprotein and tracheal gland hypertrophy in rat airways: the effect of tobacco smoke with or without the anti-inflammatory agent phenylmethyloxadiazole

A quantitative analysis has been made of tracheal gland size and of histochemical changes occurring in goblet cells of the respiratory epithelium, in rats exposed either to tobacco smoke alone or to tobacco smoke with phenylmethyloxadiazole (PMO).

Exposure to tobacco smoke alone causes an increase in goblet cell number with a shift from the production of neutral to acid glycoprotein, mainly sialidase resistant sialomucin but some sialidase sensitive sialomucin and sulphomucin. Acid glycoprotein, and each of its types, appears first at the cell apex. The addition of PMO to the tobacco protects against the increase in goblet cell number but gives no protection against the shift from neutral to acid glycoprotein and causes a larger secretory mass within the goblet cell.

In the tracheal gland exposure to smoke from either tobacco alone or tobacco with PMO causes a significant increase in cell size and acinar diameter and a lesser increase in lumen diameter. There is also an increase in the thickness of the gland and its depth. Each of these gland changes is more pronounced in those animals receiving PMO with the tobacco.

Protection of rat bronchial epithelium against tobacco smoke

Addition to tobacco of phenylmethyloxadiazole (PMO) protects rats against some of the adverse effects of exposure to cigarette smoke. Two groups of 15 rats were exposed to 25 cigarettes a day for 24 days; the group whose cigarette included PMO showed less immediate distress after exposure, a smaller tracheal goblet cell count, less thickening of the tracheal epithelium, and less cells in mitosis than those exposed to ordinary tobacco.