Phototoxicity of the tetracyclines: photosensitized emission of singlet delta dioxygen

The spectroscopic observation of 1268-nm emission of singlet oxygen photosensitized by tetracyclines in oxygenated solutions at room temperature is reported. In the series demeclocycline, tetracycline, and minocycline, the efficiency of singlet oxygen generation is found to parallel the clinical observation of relative frequency of phototoxicity of these antibiotics, suggesting singlet oxygen generation as the origin of their phototoxicity.

Effect of naloxone on the respiratory responses to hypoxia in chronic obstructive pulmonary disease

Ventilatory and airway occlusion pressure responses to hypoxia were measured in 7 subjects with chronic obstructive pulmonary disease (COPD). Paired responses were obtained after the administration of saline or naloxone and, on separate days, in 5 of the 7 subjects, after 2 saline injections. Naloxone increased (p less than 0.05) the mean inspiratory flow and the ventilatory and airway occlusion pressure responses to hypoxia when compared with the saline responses. Resting ventilation and tidal volume also increased, but not significantly. Involvement of endogenously generated opioid substances in the control of breathing of patients with COPD is further suggested by this study.

Myeloperoxidase singlet molecular oxygen generation detected by direct infrared electronic emission

Myeloperoxidase in micromolar concentrations reacting with half-millimolar stock solution H2O2 in acetate buffer containing KBr and in 50% D2O (pH + pD = 4.5) at 298 K is shown to generate singlet delta molecular oxygen efficiently. The near infrared electronic emission of singlet oxygen at 1268 nm is detected directly by novel ultrasensitive IR spectrophotometer equipment. The quantum efficiency of singlet oxygen generation by the MPO X Br- X H2O2 reaction is shown to be comparable with that of the standard chemical reaction OCl- X H2O2 at identical peroxide concentrations.

L-ascorbic acid quenching of singlet delta molecular oxygen in aqueous media: generalized antioxidant property of vitamin C

L-ascorbic acid quenches singlet (1 delta g) molecular oxygen in aqueous media (pH 6.8 for [1H]H2O and pD 7.2 for [2H]D2O) as measured directly by monitoring (0,0) 1 delta g leads to 3 sigma-g emission at 1.28 micron. Singlet oxygen was generated at room temperature in the solutions via photosensitization of sodium chrysene sulfonate; this sulfonated polycyclic hydrocarbon was synthesized to provide a water soluble chromophore inert to usual dye-ascorbate photobleaching. A marked isotope effect is found; kHQ2O is 3.3 times faster than kDQ2O, suggesting ascorbic acid is chemically quenching singlet oxygen.

Nonoperative management of bladder rupture from external trauma

Nonoperative (catheter) management was used in 18 patients with extraperitoneal rupture of the bladder with limited extravasation of dye found by retrograde cystogram. Complications occurred in 4 of the 18 patients. A review of the literature shows a 20 to 25-per cent complication rate with nonoperative management of bladder rupture. However, with a small extraperitoneal rupture with limited extravasation, especially in a female, the nonoperative (catheter) management will give a satisfactory result.

Sleep REM latency in hyperkinetic boys

This study compared the sleep-cycle characteristics of 16 hyperkinetic boys with those of 12 normal boys. The results indicated no differences between the two groups, with one exception: a subset of the hyperkinetic children had markedly short REM latencies.

Neonatal perirenal urinary extravasation with posterior urethral valves

Renal dysplasia and atrophy are associated with congenital urinary tract obstruction, such as posterior urethral valves, and are thought to result from the increased pressure in the developing obstructed urinary system. This increased pressure is likely to be alleviated by perirenal urinary extravasation and urinary ascites. Whether this relief of pressure in the obstructed developing kidney results in a lessened degree of renal abnormality is likely to depend on the time during the period of gestation when the urinary leak occurs and the degree of renal dysplasia and atrophy at the time of the urinary leak.

A comparison of the therapeutic and cardiovascular effects of a single nightly dose of Prothiaden (dothiepin, dosulepin) and Lentizol (sustained-release amitriptyline) in depressed elderly patients

This was a single-blind 4-week parallel group comparative trial in fifty depressed patients. Twenty-five patients received 50 mg of Lentizol, a sustained-release form of amitriptyline, and twenty-five received 75 mg of Prothiaden. Both groups took their drugs as a single night-time dose. Patient response was measured on a symptom check-list which was completed by the doctor and a self-rating depression scale. Tolerance was assessed by recording volunteered and observed side-effects and also by taking the pulse, blood pressure and an electrocardiogram before treatment and after 2 and 4 weeks. A statistically better response was seen with Prothiaden at each follow-up assessment (1, 2 and 4 weeks) compared to Lentizol as measured by both the symptom check-list and the self-rating scale. Less side-effects was also seen with Prothiaden. Minor changes were seen in the ECG records of two patients on Prothiaden and three on Lentizol. These changes were not associated with any clinical change in the patients' cardiovascular state. No consistent changes of any clinical significance were seen in the pulse and blood pressure recordings.

Fibrinolytic degradation products in the urine of carcinoma of the prostate patients

A study of the levels of urinary fibrinolytic degradation products was undertaken in patients with different stages of carcinoma of the prostate trying to detect latent fibrinolysis. No differences between the control group and patients with carcinoma were found. The search for a rapid screening diagnostic test for latent intravascular coagulation should be pursued in order to prevent possible bleeding complications in these patients.

Energy transfer from PO excited states to alkali metal atoms in the phosphorus chemiluminescence flame

Phosphorus chemiluminescence under ambient conditions of a phosphorus oxidation flame is found to offer an efficient electronic energy transferring system to alkali metal atoms. The lowest resonance lines, (2)P(3 / 2),(1/2)-->(2)S((1/2)), of potassium and sodium are excited by energy transfer when an argon stream at 80 degrees C carrying potassium or sodium atoms intersects a phosphorus vapor stream, either at the flame or in the postflame region. The lowest electronically excited metastable (4)II(i) state of PO or the (PO[unk]PO)(*) excimer is considered to be the probable energy donor. The (PO[unk]PO)(*) excimer results from the interaction of the (4)II(i) state of one PO molecule with the ground (2)II(r) state of another. Metastability of the donor state is strongly indicated by the observation of intense sensitized alkali atom fluorescence in the postflame region.

Sacral agenesis: an analysis of 11 cases and review of the literature

Sacral agenesis is an uncommon condition associated with familial diabetes mellitus and complicated pregnancy. The condition is characterized by gluteal skin dimpling, loss of gluteal fold, myelomeningocele, sacral lipoma, as well as numerous orthopedic, anorectal and other widespread anomalies. The motor nerve deficit, for example poor anal sphincter tone, is more pronounced than the sensory nerve deficit, for example perianal anesthesia. Diagnosis is made by anteroposterior and lateral spinal x-rays. All of our patients had bladder or external sphincter dysfunction, while 91 per cent had vesicoureteral reflux. Early diagnosis and conservative management with intermittent catheterization and uropharmacological agents are now advocated.

Reversible upper tract dilatation with ileal conduit stomal ulceration or encrustation

Six pediatric patients with progressive upper tract dilatation were noted to have stomal encrustation and ulceration. In all cases, the upper tract dilatation subsided with effective conservative treatment of the stomal lesion thus obviating surgical revision of the stoma.

Primary carcinoma in situ of the ureter and renal pelvis

Primary carcinoma in situ of the ureter or renal pelvis is rare. We describe 3 patients, each of whom had a different mode of presentation. When malignant cells in the urine from the upper urinary tract are associated with urographic evidence of an appropriate lesion, aggressive surgical therapy is indicated. In the absence of such a urographic abnormality patients with positive cytologic examinations should be followed closely because the exfoliated cells usually are from poorly differentiated neoplasms.

Reevaluation of vest technique of vesicourethral reconstruction in radical retropubic prostatectomy

Vesicourethral reconstruction after radical retropubic prostatectomy was done by the Vest technique in 36 patients and by direct vesicourethral anastomosis in 100 patients. Complications resulting from the two methods of vesicourethral reconstruction were similar. Incontinence after radical retropublic prostatectomy appears not to be related to the method of vesicourethral reconstruction but occurs because of damage during surgery or postoperative scarring of the distal sphincteric mechanism.

Winter sports-related urologic trauma

There is no characteristic pattern of ski-related urologic injuries except those associated with major blunt abdominal trauma. Isolated urologic injuries and injuries of the lower urinary tract are relatively uncommon.

Immunological donor pretreatment in combination with pulsatile preservation in cadaveric renal transplantation

The extended experience on the efficacy of pretreating the cadaveric renal allograft donor by means of large doses of cyclophosphamide and methylprednisolone (group A, 36 kidneys) was compared with the experience regarding untreated renal allografts (group B, 32 kidneys). Kidneys in both groups were perfused by pulsatile means using cryoprecipitated plasma. There was a significant difference in allograft survival (72% in group A versus 36% in group B at 3 years by actuarial means). Also, large doses of cyclophosphamide and methylprednisolone as pretreatment did not cause any detrimental effect to the allograft kidney when used in combination with cryoprecipitated plasma and pulsatile perfusion.

Effect of thoracentesis on arterial oxygen tension

The acute effects of thoracentesis on arterial oxygenation were observed in 19 studies on 17 patients. Arterial blood samples were obtained prior to, immediately after, and 1 h after thoracentesis. Unpredictable changes in the arterial oxygen tension, ranging from -22 to +19 mm Hg were found immediately following thoracentesis. It was concluded that significant hypoxemia may result from thoracentesis due to aberration of ventilation-perfusion relationships. It is further suggested that oxygen therapy be routinely administered during and immediately after the procedure.

The role of air pollution and weather changes in childhood asthma

Eighty asthmatic children were studied for two years. Daily records of various parameters of asthma were correlated with levels of different air pollutants and such climatological factors as bad weather conditions and temperature changes. High levels of ozone and carbon monoxide significantly correlated with the number, duration and the severity of asthmatic attacks. However, all the factors combined played only a minor role in the complex etiology of asthma, accounting for only 5 percent to 15 percent of the total variance.

Deconditioning of exercise-induced asthma

The majority of asthmatic children develop a significant degree of bronchospasm after a moderate amount of exercise. Etiology of this phenomenon has remained unknown. Pulmonary function tests, measurements of blood gases, and immunological assessments have been essentially normal. This study was designed to investigate the role of conditioning process in the development of exercise-induced bronchospasm (EIB). Fifty asthmatic children, between the ages of 8 and 15, were subjected to a standardized test of exercise. Thirty-six of the children who developed EIB were divided into an experimental and a control group. The experimental procedure was designed as a classical extinction procedure in which the conditioned stimulus (exercise) was presented without the occurrence of conditioned response of EIB. Only the experimental group received isoproterenol inhalation before the exercise to prevent the occurrence of EIB, while the control groups received plain air in a similar manner. The experimental group showed a significant improvement after the extinction procedure. A 6 month follow-up indicated that the majority of the children in the experimental group maintained the gains that were acquired during the experimental procedure.