Effects of D-4F on vasodilation, oxidative stress, angiostatin, myocardial inflammation, and angiogenic potential in tight-skin mice

Systemic sclerosis (scleroderma, SSc) is an autoimmune, connective tissue disorder that is characterized by impaired vascular function, increased oxidative stress, inflammation of internal organs, and impaired angiogenesis. Tight skin mice (Tsk−/+) have a defect in fibrillin-1, resulting in replication of many of the myocardial and vascular features seen in humans with SSc. D-4F is an apolipoprotein A-I (apoA-I) mimetic that improves vascular function in diverse diseases such as hypercholesterolemia, influenza, and sickle cell disease. Tsk−/+ mice were treated with either phosphate-buffered saline (PBS) or D-4F (1 mg·kg−1·day−1 for 6–8 wk). Acetylcholine and flow-induced vasodilation were examined in facialis arteries. Proinflammatory HDL (p-HDL) in murine and human plasma samples was determined by the cell-free assay. Angiostatin levels in murine and human plasma samples were determined by Western blot analysis. Hearts were examined for changes in angiostatin and autoantibodies against oxidized phosphotidylcholine (ox-PC). Angiogenic potential in thin sections of murine hearts was assessed by an in vitro vascular endothelial growth factor (VEGF)-induced endothelial cell (EC) tube formation assay. D-4F improved endothelium-, endothelial nitric oxide synthase-dependent, and flow-mediated vasodilation in Tsk−/+ mice. Tsk−/+ mice had higher plasma p-HDL and angiostatin levels than C57BL/6 mice, as did SSc patients compared with healthy control subjects. Tsk−/+ mice also had higher triglycerides than C57BL/6 mice. D-4F reduced p-HDL, angiostatin, and triglycerides in the plasma of Tsk−/+ mice. Tsk−/+ hearts contained notably higher levels of angiostatin and autoantibodies against ox-PC than those of control hearts. D-4F ablated angiostatin in Tsk−/+ hearts and reduced autoantibodies against ox-PC by >50% when compared with hearts from untreated Tsk−/+ mice. Angiogenic potential in Tsk−/+ hearts was increased only when the Tsk−/+ mice were treated with D-4F (1 mg·kg−1·day−1, 6–8 wk), and cultured sections of hearts from the D-4F-treated Tsk−/+ micewere incubated with D-4F (10 μg/ml, 5–7 days). Failure to treat the thin sections of hearts and Tsk−/+ mice with D-4F resulted in loss of VEGF-induced EC tube formation. D-4F improves vascular function, decreases myocardial inflammation, and restores angiogenic potential in the hearts of Tsk−/+ mice. As SSc patients have increased plasma p-HDL and angiostatin levels similar to the Tsk−/+ mice, D-4F may be effective at treating vascular complications in patients with SSc.

Adolescent urinary tract infections

Urinary symptoms in adolescents are common, particularly in females. Urinary tract infections (UTIs) cause many of these symptoms. For uncomplicated UTIs, both lower and upper tract, therapy is straightforward. Commonly used antibiotics are trimethoprim/sulfamethoxazole (TMP/SMX), cefixime, and ciprofloxacin (off-label use) for 3 days for lower tract infections and 10ñ14 days for upper tract infections. Adolescent UTIs are markers for sexual activity, just as UTIs in younger children are often markers for anatomic defects, e.g., congenital abnormalities. Adolescents with upper and lower UTIs often have concurrent sexual activity or a complication of that activity. Issues among adolescents with UTIs are more similar to those of young adults than to those of younger children. It is as important to counsel adolescents about sexual activity and its consequences as it is to treat the UTIs. All adolescents with UTIs should be queried for sexual activity; evidence of sexually transmitted diseases (STDs) should be sought; and counseling for STDs and responsible sexual activity is recommended. Complicated UTIs include those in patients who have grown into adolescence after a childhood of infections or who have anatomic abnormalities, recurrent infections, reflux and reflux nephropathy, spina bifida and neurogenic bladder, transplanted kidneys, diabetes, and urolithiasis. These patients require individualized medical programs, unique for their condition, history, and microbiology.

Effects of multiple-dose maternal ethanol infusion on fetal cardiovascular and brain activity in lambs

Ethanol (2 gm/kg of maternal body weight administered in four equal doses of 0.5 gm/kg over 5 hours) was infused intravenously into nine chronically prepared pregnant ewes between 124 and 137 days' gestation. The data demonstrated a dose-response relationship between fetal arterial ethanol concentrations and the incidence of fetal breathing movements. Suppression of normal fetal electrocortical activity occurred at a low ethanol concentration and returned to control values at a time of very high arterial ethanol concentrations. This experimental model of a binge drinking episode further supports the hypothesis that ethanol suppresses fetal breathing movements by a direct central mechanism rather than indirectly by alteration of electrocortical activity.

Cerebral oxidative metabolism in fetal sheep with multiple-dose ethanol infusion

Cerebral oxidative metabolism and cotylendonary blood flow were measured in 10 unanesthetized fetal sheep (127 to 132 days' gestation) during a control period, after the first, third, and fourth infusions of four doses of 0.5 gm of ethanol per kilogram of maternal body weight infused into the ewe during 5 hours, and 24 hours after ethanol infusion. Preductal arterial and sagittal vein blood samples were analyzed for oxygen content, blood gases, pH, and ethanol. Cerebral and cotylendonary blood flow were measured with a radioactive microsphere technique. Fetal blood gases and pH changed little with the ethanol infusions, although PaO2 and oxygen content decreased 24 hours after ethanol infusion. Cotylendonary blood flow, which was decreased after the third and fourth ethanol infusions, did not account for these delayed hypoxemic changes. Similarly, cerebral oxidative metabolism was decreased when measured after each of the ethanol infusions, with no dose response or tolerance evident. This noted fall in fetal cerebral oxidative metabolism appears to be a direct depressant effect that was maximal at rather low fetal ethanol levels, which, if prolonged, might well affect cerebral growth and development. Recovery of cerebral metabolic function appeared complete by 24 hours. However, relative fetal hypoxemia was evident at this time, the mechanism of which remains to be determined.

Effects of maternal ethanol infusion on fetal cardiovascular and brain activity in lambs

Ethanol (1 gm/kg of maternal body weight administered over 1 hour) was infused intravenously into 11 chronically prepared pregnant ewes between 128 to 137 days' gestation. Fetal breathing movements were suppressed for 9 hours following ethanol administration, and both high- and low-voltage fetal electrocortical activity were suppressed for 3 hours and replaced by intermediate-voltage electrocortical activity. Fetal blood gases and pH were not altered. These data support the hypothesis that ethanol suppresses fetal breathing movements by a direct central mechanism rather than indirectly by alteration of electrocortical activity.

Maternal glucose injections do not alter the suppression of fetal breathing following maternal ethanol ingestion

In order to determine whether intravenous injections of glucose could reverse the effects of maternal ingestion of ethanol (0.25 gm/kg), glucose (25 gm intravenously) or an equal volume of saline solution was administered to eight pregnant women at 37 to 40 weeks' gestation after ingestion of ethanol. Fetal breathing movements were abolished within 30 minutes after ingestion of ethanol and were not increased by maternal intravenous injections of glucose. Maternal heart rate was increased by ethanol. The disposition of ethanol in maternal blood was not altered by injection of glucose, and fetal gross body movements were not influenced by maternal ingestion of ethanol or by injections of glucose after ethanol.

The anaemic inpatient. A survey of current hospital practice

The haemoglobin levels of all patients in a large teaching hospital (except those receiving cytotoxic chemotherapy or radiotherapy) were examined over a three-week period. One hundred and eleven patients with haemoglobin levels below 100 g/L were found, and the approach to this problem by the clinicians was scrutinized. In most patients, there was a good and obvious explanation for the anaemia; in just under 50%, however, the causes were often mixed or less obvious. Frequently the anaemia was not investigated when, perhaps, it should have been and, when treated, it was often treated inappropriately. Excessive, inappropriate and indiscriminate use of oral iron therapy was a prominent finding.

Effect of maternal ethanol ingestion on fetal breathing movements, gross body movements, and heart rate at 37 to 40 weeks' gestational age

The effect of maternal ingestion of ethanol (0.25 gm/kg) on fetal breathing movements, gross fetal body movements, and fetal heart rate was studied in 11 healthy pregnant women at 37 to 40 weeks' gestation. Fetal breathing movements were almost abolished within 30 minutes of the alcoholic drink and remained significantly decreased for 3 hours. The incidence of gross fetal body movements before or after ethanol was not different from that on the control day, and the fetal heart rate was not changed after maternal ingestion of ethanol.

Regional release of [3H]dopamine from rat brain in vitro: effects of opioids on release induced by potassium, nicotine, and L-glutamic acid

Previous studies have suggested that the release of dopamine (DA) in the rat brain may be sensitive to modulation by opioid agents, including the endogenous opioid peptides (enkephalins and endorphins). The present study examined the effects of morphine and the enkephalin analogue D-Ala2-Met5-enkephalinamide (DALA) on the release of radiolabeled DA from superfused slices of rat brain regions. The release of preloaded [3H]DA was evoked from slices of the caudate-putamen (CP) by application of potassium (K+), nicotine (NIC), or L-glutamic acid (L-GLU). The release of [3H]DA from slices of the nucleus accumbens (NA), olfactory tubercle (OT), and substantia nigra (SN) was evoked by L-GLU. Both K+ and NIC evoked a concentration-related release of [3H]DA from CP slices. K+-induced release was only partially dependent on calcium (Ca2+), while NIC-evoked release was completely Ca2+ independent. Neither morphine nor DALA influenced the release of [3H]DA evoked by K+ or NIC. L-GLU produced a concentration-dependent release of [3H]DA from slices of CP, NA, OT, and SN. In all four brain regions, this release was (a) Ca2+-dependent, (b) strongly inhibited by low concentrations of magnesium (Mg2+), (c) greater than the release evoked by D-GLU, (d) attenuated by the putative L-GLU receptor antagonist glutamic acid diethylester (GDEE), and (e) insensitive to tetrodotoxin (TTX) except in the SN. Morphine produced a significant inhibition of L-GLU-evoked [3H]DA release from all four regions. Naloxone, which by itself had no significant effect on the L-GLU-evoked release of [3H]DA, blocked the inhibitory effect of morphine on this release in the CP but not in the other regions. Levorphanol and dextrorphan were equipotent in reducing the glutamate-stimulated release of [3H]DA from CP slices. DALA had no effect on L-GLU-induced release in any of the brain regions examined. The results indicate that L-GLU provokes regional release of DA by acting at a Mg2+-sensitive glutamate receptor. This release is selectively modified by morphine through a mechanism which is insensitive to naloxone.