The newer unconventional indications of permanent pacemakers

In recent years, the indications for permanent pacemakers have expanded. The interest has focussed on hypertrophic cardiomyopathy, dilated cardiomyopathy and a new entity called hypertensive hypertrophy with cavity obliteration (HHCO). Pacemaker therapy is establishing itself for the prevention of atrial fibrillation. Pacing for neurocardiogenic syncope with newer pacing mode has encouraging datas. Pacemaker for long QT syndrome, after cardiac transplant and for haemodynamic improvement in occasional cases of first degree atrio-ventricular block is getting attention. The AHA and ACC guidelines updated in 1998 for implantation of cardiac pacemakers, now include several of these newer indications.     

Responses of lateral hypothalamic glucose-sensitive and glucose-insensitive neurons to chemical stimuli in behaving rhesus monkeys.

1. Extracellular single neuron activity was recorded in the lateral hypothalamic area (LHA) of awake, behaving monkeys, with particular regard to the feeding-related functional characteristics of glucose-sensitive (GS) versus glucose-insensitive (GIS) neurons. Firing rate changes were recorded by means of carbon fiber, multibarreled glass microelectrodes during 1) microelectrophoretic application of various chemicals, 2) gustatory and olfactory stimulation, and 3) a high fixed-ratio schedule (FR) bar press feeding task. 2. In 336 neurons examined, 91 (27%) were suppressed by electrophoretically administered glucose, and so they were designated as GS cells. The 245 neurons (73%) in which the firing rates did not change during glucose applications were pronounced GIS. The 179 GS and GIS cells tested exhibited different responses to the catecholamines (CAs), noradrenaline (NA) and dopamine (DA), both of which are intimately involved in the control of feeding. More GS neurons responded to NA than did GIS cells; the predominant effect of both CAs on GS neurons was inhibition. 3. The taste responsiveness of 111 LHA neurons was examined. Fifty-seven cells (52%) showed responses to gustatory stimulation. Of 50 GS neurons tested, 33 (66%) exhibited firing rate changes to tastes. On the contrary, only 24 (39%) of the 61 GIS neurons examined responded to gustatory stimuli. Activity changes of GS neurons commonly occurred to two or more tastants, in distinction to the relative gustatory specificity shown by GIS cells. 4. Two hundred fifty-six (84%) of the 303 neurons tested responded during one or more phases of the bar press feeding task. Most activity changes occurred during the bar press (BP) and reward (RW) periods, however numerous phasic responses to cue light (CL) and cue tone (CT) were also observed. A higher proportion of the GS neurons showed task-related activity changes than did the GIS cells (77, 95% and 179, 81%, respectively). GS neurons responded more during the BP phase and to the food reward; GIS cells were more responsive during the CL that enabled acquisition and the CT that signaled reward. Thus GS neurons were responsive during the acquisition and consumption of reward, whereas GIS cells responded to external cues signaling both of these events. The gustatory neurons displayed specific task-related activity changes only in the CL (GIS cells) and BP phases (GS neurons), that is, in phases most intimately involved in sensory-motor integration. 5. Two-thirds of the 30 GS neurons tested were responsive to both gustatory and olfactory stimulation as opposed to only one-third of GIS cells.(ABSTRACT TRUNCATED AT 400 WORDS)     

Metastatic embryonal rhabdomyosarcoma of the breast: A case report and literature review

Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.     

Is the IV obstructed or infiltrated? A simple clinical test

Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.     

Success in Surgical Intervention for Morbid Obesity: Is Weight Loss Enough?

Varieties of gastric surgery have increasingly been used in the management of morbid obesity. Generally, however, research and commentary in this area have related to surgical technique, with weight loss or morbidity being regarded as the most important dependent measures. In the context of the publication of several papers relating to the effects of surgery in the long-term, we believe that it is timely for surgeons to examine their criteria for success. In this paper, we argue that weight loss is inadequate as a primary criterion for success in this context, and that the value of the intervention should be measured against a multidimensional concept of success.     

A combination of amoxicillin and clavulanic acid in the treatment of pyoderma in children

The efficacy and safety of amoxicillin plus clavulanic acid was compared with that of amoxicillin, erythromycin and co-trimoxazole in an open label, randomized trial in 50 children in each group (total 200) with mild to severe pyodermas. Majority (47%) had impetigo. Fifty (25%) children had mild pyoderma, 56 (28%) had moderate and 94 (47%) children had severe pyoderma. Pure growth of S aureus was isolated in 130 (65%) children, S pyogenes in 42 (21%) and both organisms in 28 (14%) children. In mild to moderate pyoderma either of the drug tried was equally effective. In severe pyoderma, 24 of twenty five (96%) children receiving amoxicillin plus clavulanic acid, 18 of twenty (90%) children in amoxicillin group, 20 of twenty four (83.3%) children in erythromycin group and 13 of twenty five (52%) children in co-trimoxazole group showed clinical cure of therapy. Amoxicillin combined with clavulanic acid was well tolerated in children and there was no significant side effect except mild diarrhoea in two cases (4%) which was well controlled by taking the drug with meals.     

多途径丝裂原激活的蛋白激酶介导一氧化氮引起的肝癌细胞凋亡

目的研究非离子型的diazeniumdiolate类一氧化氮供体引起肝癌细胞凋亡的分子机制.方法利用免疫印迹、免疫沉淀、凝胶阻滞实验研究一氧化氮供体处理Hep3B肝癌细胞后,丝裂原激活的蛋白激酶、AP-1的激活以及和Hep3B肝癌细胞凋亡的关系.结果一氧化氮可引起细胞外信号调节蛋白激酶、c-jun N末端激酶和p38激酶的激活,特别是细胞外信号调节的蛋白激酶的持续激活,其中细胞外信号调节的蛋白激酶和c-jun N末端激酶的特异的阻断剂U0126和JNK抑制剂Ⅱ可阻断AP-1的激活和Hep3B细胞的凋亡,而p38激酶的阻断剂SB203580不能阻断AP-1的激活和Hep3B肝癌细胞的凋亡.结论一氧化氮通过激活细胞外信号调节蛋白激酶、c-jun N末端激酶,进而激活AP-1而引起Hep3B肝癌细胞的凋亡.     

Clinical and biochemical features of sporadic and hereditary phaeochromocytomas: an analysis of 41 cases investigated in a single endocrine centre.

The aims of this study were to estimate the prevalence of phaeochromocytomas among adrenal tumours and to analyse the clinical and biochemical features of sporadic and hereditary tumours. Our series of 609 adrenal tumours evaluated between January 1995 and July 2003 was reviewed. Catecholamine content in phaeochromocytoma tissues was also determined and correlated with clinical behaviour and biochemical parameters of patients. Forty-one (6.7%) of the 609 patients had phaeochromocytomas, of which 28 were sporadic (25 benign and three malignant) and 13 (all benign) were associated with hereditary diseases (multiple endocrine neoplasia type 2A in seven cases from four unrelated families carrying mutations of the RET gene, von Hippel-Lindau disease in two unrelated cases with mutations of the VHL gene, and type 1 neurofibromatosis in four unrelated cases). Bilateral tumours were found in three patients with hereditary syndromes and in one sporadic case. Tumour diameter was slightly but not significantly greater in patients with hereditary than in those with sporadic tumours. Systolic but not diastolic blood pressure was significantly higher in patients with sporadic compared with those with hereditary tumours, but comparison of other clinical data and biochemical parameters indicated an absence of significant differences in the mean age, presenting symptoms, heart rate, or fasting serum glucose levels. Tissue catecholamine content measured in 8 sporadic and 5 hereditary phaeochromocytomas was highly variable and it failed to show significant differences between hereditary and sporadic tumours. These results indicate a high proportion of hereditary diseases among patients with phaeochromocytomas. Genetic and clinical testing for hereditary diseases may be of great help to offer an appropriate treatment, follow-up and family screening for these patients.     

Treatment of Cervical Incompetence by Transabdominal Cervicoisthmic Cerclage

Summary: Cervical incompetence is a condition traditionally treated by cervical cerclage which in most cases is inserted via the transvaginal route. However the insertion of a transabdominal cervicoisthmic suture is indicated in those patients with recurrent mid-trimester losses due to an incompetent cervix where it is not technically possible to insert a transvaginal suture. Between 1987 and 1996, 12 women at the Royal Women's Hospital, Melbourne were treated with transabdominal cervicoisthmic cerclage (TCC). Eight patients had cerclage in the nonpregnant state, and 4 were pregnant at the time. The completed pregnancies thus far have resulted in 10 surviving infants, a successful pregnancy rate of 69.2%. This compares favourably with a corrected preTCC successful pregnancy rate of only 13%. There were minimal intraoperative complications in our series. Bleeding, chorioamnionitis and premature rupture of the membranes have been reported elsewhere and occurred in 2 of our patients. Our results and a review of the literature confirms that TCC has an important role in carefully-selected patients.     

Frontal sinus surgery 2004: update of clinical anatomy and surgical techniques

Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery.