Repeated intracerebral microinjections: efficacy in studying brain functions

Injection of chemicals into the brain has been considered as an important technique to study various functions of the brain. In these studies, as a rule, only one bilateral injection is given in one animal. This study was undertaken to evaluate the quality of the body temperature data obtained after first and second injections of methoxamine and artificial cerebrospinal fluid into the medial preoptic area. Though there was quantitative decrease in the effects produced after the second injection of the drug, there was no significant change in the effects produced by the second injections of artificial cerebrospinal fluid, which was used as a vehicle. Results of this study support the earlier recommendation to perform only one injection in any of the brain sites for evaluating the effect of any drug. But the vehicle can be administered as a second injection, without compromising on the quality of data.     

Darier's disease following radiotherapy for carcinoma of cervix

Darier-White disease is due to a defect in the ATP2A2 gene encoding the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA2b). We report a case of carcinoma cervix in whom Darier's disease manifested after the initiation of radiation therapy. Conventional cytogenetics on peripheral blood revealed non-clonal constitutional autosomal and X chromosome abnormalities suggesting radiation induced gene toxicity. Occurrence of Darier's disease in our case could be due to treatment induced sustained differentiation in the Darier's affected skin by an unknown mechanism. Late onset or sporadic Darier's disease is the other possibility.     

Sleep-related penile erections do not occur in rats during carbachol-induced rapid eye movement sleep

This study was undertaken to find out whether sleep-related penile erections occur in the carbachol-induced rapid eye movement sleep model in rats. Bulbospongiosus EMG, as a measure of penile erection, was recorded along with EEG, EMG, and EOG during normal sleep-wakefulness. These parameters were again recorded after injection of carbachol into the pontine tegmentum. Carbachol-induced rapid eye movement sleep was not accompanied by penile erections.     

Use of chlorophyll fluorescence in metal-stress research: a case study with the green microalga Scenedesmus

Metal toxicity on the photosystem II (PS II) photochemistry of the green microalga Scenedesmus obliquus was investigated in vivo using a pulse-amplitude-modulated fluorometer. The results demonstrated that the test metals (copper, chromium, nickel, cadmium, and zinc) inhibited PS II photochemistry substantially, which was clearly evident for F0, Fv/Fm, qN, and qP following 12h of metal exposure, whereas Fm, Fv/2, and F0/Fv depicted significant alteration after only 1h of treatment. Thus, metals are not only found to affect the initial and maximal fluorescence, maximum quantum yield, photochemical and nonphotochemical quenching, and plastoquionone pool but the water-splitting apparatus was also significantly altered under metal stress. Among all these fluorescence characteristics, the F0/Fv registered the highest sensitivity to all the five test metals, thus indicating that the water-splitting apparatus of the oxidizing side of PS II is the primary site of action of toxic metals. This study therefore, concludes that F0/Fv ratio can be used as a powerful tool in metal-stress research.     

A prospective randomised controlled trial of capnography vs. bronchoscopy for Blue Rhino percutaneous tracheostomy

A crucial step for successful percutaneous tracheostomy is the introduction of the needle and guide wire into the trachea. Capnography has recently been proposed as one way to confirm tracheal needle placement. In this randomised controlled study, we used capnography in 26 patients and bronchoscopy in 29 patients to confirm needle placement for percutaneous tracheostomy using Blue Rhino kit. The operating times and the incidence of peri-operative complications were similar for both groups. Capnography proved to be as effective as bronchoscopy in confirming correct needle placement.     

Urinary morbidity after 125I brachytherapy of the prostate

OBJECTIVE: To assess urinary morbidity within the first 6 months after transperineal prostate brachytherapy (TPBT) with 125I for localized prostate adenocarcinoma. PATIENTS AND METHODS: Between September 2000 and July 2001, 50 consecutive patients with favourable early-stage prostate cancer were treated with TPBT. Clinical and objective investigations, including uroflowmetry and postvoid residual urine measurements, were evaluated for short-term urinary morbidity; predictive factors were also sought. RESULTS: Thirty-eight (76%) patients developed urinary disorders, but severe urinary complications were exceptional. The International Prostate Symptom Score (IPSS) changed significantly during the first and third month after implantation and then improved during the sixth month. Concomitantly, the maximum and the average urinary flow rate deteriorated significantly. The variations in postvoid residual were less significant. An initial IPSS of > 8 and previous alpha-blocker treatment were identified as significant predictive factors of urinary morbidity, as were the TPBT dose received by 90% of the target volume and by 30% of the urethra, and the volume of prostate receiving 144 Gy. CONCLUSION: Urinary morbidity after TPBT is frequent but rarely exceptionally severe; patients must therefore be given full information. Patients with a higher initial IPSS or having had previous alpha-blocker treatment, with their associated dosimetric factors, are at greater risk of these urinary morbidity.     

Disorders of the lymph circulation: their relevance to anaesthesia and intensive care

The lymphatic system is known to perform three major functionsin the body: drainage of excess interstitial fluid and proteinsback to the systemic circulation; regulation of immune responsesby both cellular and humoral mechanisms; and absorption of lipidsfrom the intestine. Lymphatic disorders are seen following malignancy,congenital malformations, thoracic and abdominal surgery, trauma,and infectious diseases. They can occasionally cause mortality,and frequently morbidity and cosmetic disfiguration. Many lymphaticdisorders are encountered in the operating theatre and criticalcare settings. Disorders of the lymphatic circulation relevantto anaesthesia and intensive care medicine are discussed inthis review. Br J Anaesth 2003; 91: 265–72