Coiled-spring sign of appendiceal intussusception

Appendiceal intussusception has been considered a rare entity that is difficult to diagnose radiographically. However, a characteristic coiled-spring appearance in the cecum with nonfilling of the appendix has been observed on double-contrast barium enema (DCE) examinations in 11 cases of apparent or proved appendiceal intussusception. In two surgically proved cases, the intussusception was precipitated by an appendiceal mucocele and by endometriosis implants in the appendix. In four other cases, the intussusception was transient and the coiled-spring defect in the cecum disappeared with filling of the appendix on the DCE examination (three cases) or on a subsequent barium enema study (one case). The remaining five cases were unproved, although two patients had undergone prior appendectomy and the coiled-spring finding presumably resulted from an intussuscepted appendiceal stump. Only one patient was found to have appendiceal-related symptoms. It appears that appendiceal intussusception often occurs as a transient phenomenon in asymptomatic patients, and that it can be diagnosed on the routine DCE examination by a characteristic coiled-spring defect in the cecum.     

Haemodynamic effects of atenolol, labetalol, pindolol and captopril: a comparison in hypertensive patients with special reference to changes in limb blood flow, heart rate and left ventricular function.

1 To compare the haemodynamic effects of secondary characteristics of beta-adrenoceptor blockers with an angiotensin converting enzyme inhibitor forty patients with previously untreated mild to moderate hypertension were prescribed either atenolol 50-100 mg day-1, labetalol 200-800 mg day-1, pindolol 10-30 mg day-1 or captopril 25-100 mg day-1 and observed for 6 months. 2 Over this period: (a) All four drugs produced similar reductions in blood pressure at rest (P less than or equal to 0.01) and after exercise (P less than or equal to 0.01). (b) All four drugs significantly decreased resting forearm (P less than or equal to 0.01) and calf blood flow (P less than or equal to 0.01). They all also caused a significant reduction in the increased calf blood flow following exercise (P less than or equal to 0.01). (c) No drug produced a change in resting forearm vascular resistance, while resting calf vascular resistance was decreased by captopril and pindolol, unaltered by labetalol and increased by atenolol. Post-exercise calf vascular resistance was increased by atenolol, labetalol and pindolol but unaltered by captopril. (d) Although all four drugs produced a fall in resting heart rate this was significantly greater for atenolol and labetalol (P less than or equal to 0.01). All four treatments however significantly reduced the increase in heart rate following exercise (P less than or equal to 0.01). (e) No drug produced any significant change in resting and post-exercise stroke volume/ejection fraction. 3 It is concluded that despite differing modes of action all four drugs reduce limb blood flow. This primarily appears to be a consequence of reduced perfusion pressure associated with limited autoregulation of skeletal muscle circulation. The reduction in arterial vascular resistance produced by captopril and pindolol is inconsistent and does not appear of major benefit in preserving limb blood flow. The reduction in perfusion with the agents studied may in part be related to a fall in cardiac output associated with decreased heart rate. This suggests that captopril may exert antisympathetic activity when used as an antihypertensive agent.     

The effect of renal artery stenting on hypertension and renal function in patients with atherosclerotic renovascular disease

IntroductionAtheroscleroticrenal arterystenosisisassociatedwithhypertension ,progressivelossofrenalfunctionandrecurrentpulmonaryedema [1 3].Althoughsurgicalrevascularizationhasbeenshowntoimprovebloodpressurecontrol,preserveorstabilizerenalfunction [4 ],andreverseend stagerenalfailure[5 ],itsmorbidityandmortalityrateshavebeenhigherthanthoseofstentrevascularization [6 ].Stentrevascularizationhasbeenshowntobesuperiorto“balloononly”angioplastyandsurgicalrevascularization [7].Thisstudyevaluatesth…     

Further evidence that one of the earliest alterations in colorectal carcinogenesis involves APC.

Colorectal cancer is hypothesized to arise after the accumulation of multiple mutations in critical oncogenes or tumor suppressor genes. The relative timing of each mutation is unknown because the exact number and types of mutations differ between tumors. However, for every mutation except the first, tumor heterogeneity must exist until clonal dominance is reestablished. This principle was applied to mutant APC genes in eight colorectal adenomas. The APC mutations were homogeneously present throughout the adenomas, including those less than 1 cm in size, but absent from the normal polyp stalks. In one adenoma with APC and c-K-ras mutations, both mutations were simultaneously present in only a small discrete portion, suggesting that the c-K-ras mutation was acquired after the APC mutation. These findings suggest that when mutations in APC occur, they are usually one of the first events in colorectal carcinogenesis or provide such a strong selective advantage that intratumor heterogeneity is seldom observed.     

维A酸受体药物的研究回顾及皮肤临床应用的评介

目的：人们对维生素A的认识始于1600年，本旨在探讨其衍生物维A酸（RA）和相应的靶位研究进展。方法；综合近年来国内外献进行分析，介绍研究进展和受体特点，对其临床应用进行评价。结论：维生素A酸类药物进展迅速，治疗范围在不断地拓展，为治疗皮肤疾病展现了良好的前景。     

Effects of norepinephrine on the dog common carotid, coronary and renal arteries: in vitro studies

The effects of norepinephrine were studied on segments of the common carotid, left circumflex and renal arteries of dogs with the endothelium intact and removed. Norepinephrine induced a dose-dependent increase in tension in segments of the renal and carotid artery but did not produce any effect on the coronary artery. Although the absence of endothelium did not affect the magnitude of the norepinephrine-induced vasoconstriction of the renal artery, it elicited a more pronounced response in the carotid artery in which the endothelium was removed. Our data suggest that the vascular response to norepinephrine is dependent upon the specific arterial bed and, secondly, that the endothelium plays a determinant role in the magnitude of the response of the carotid artery.     

Hemorrhagic intracranial malignant neoplasms: spin-echo MR imaging

Twelve patients with 15 separate, spontaneously hemorrhagic, intracranial malignant lesions (seven primary gliomas, eight metastatic lesions) were examined with spin-echo magnetic resonance imaging at 1.5 T, and with computed tomography. The signal intensity patterns of these lesions, as seen on both short repetition time (TR)/short echo time (TE) and long-TR/long-TE spin-echo pulse sequences, were compared with the previously described appearance at 1.5 T of non-neoplastic intracerebral hematomas. The images of hemorrhagic intracranial malignancies showed notable signal heterogeneity, often with identifiable nonhemorrhagic tissue corresponding to tumor; diminished, irregular, or absent hemosiderin deposition; delayed hematoma evolution; and pronounced or persistent edema, compared with non-neoplastic hematomas. The demonstration of these characteristics in the appropriate clinical setting may suggest malignancy as the cause of an intracranial hematoma.     

Kinetic analysis of albumin-mediated uptake of warfarin by perfused rat liver

We previously found that the uptake of warfarin in the presence of albumin by perfused rat liver could not be explained simply by the unbound warfarin concentration. The aim of the present study is to develop a kinetic model to account for this albumin-mediated uptake of warfarin. Single circulation indicator dilution studies on warfarin uptake were carried out in the isolated perfused rat liver in the absence and presence of various concentrations of bovine serum albumin (BSA) in the perfusate. A distributed model was fitted to the dilution data and the estimates of the influx, efflux, and sequestration rate constants were obtained. The results showed that the predicted concentration of the unbound warfarin is not high enough to explain the observed uptake rate; the liver cell surface appears to reduce the binding affinity of warfarin for BSA to 1/20 of that observed in vitro. A kinetic model which considers the interaction between albumin and the liver cell surface was fitted to the uptake rates of warfarin over a wide range of BSA concentration. The model gave a dissociation constant of the cell surface for albumin of 160 microM, which is comparable with those reported by others for the hepatic extractions of free fatty acids and rose bengal. Based on this kinetic model, the contributions of the unbound and bound warfarin to its hepatic uptake were estimated, and the bound warfarin was found to contribute most in the physiological albumin concentration range.     

Trends in morbidity and mortality of hepatic resection for malignancy. A matched comparative analysis.

OBJECTIVE: The authors define more clearly the trends in morbidity and mortality after hepatic resection for malignant disease in matched patient groups during two discrete time periods. SUMMARY BACKGROUND DATA: Recent reports have shown improvement in operative morbidity and mortality associated with hepatic resection; however, results often included resections for benign disease and trauma. Furthermore, specific factors contributing to the improvement in operative risks between the last two decades have not been defined. METHODS: A retrospective matched comparative analysis was conducted of patients with primary and metastatic hepatic malignancy resected with curative intent between two periods (1976 to 1980 and 1986 to 1990). Eighty-one patients met our inclusion criteria in the early period; this group was matched with 81 patients from the latter period by the following four parameters: age, gender, type of malignant disease, and extent of resection. Records of these two patient groups were abstracted for clinical presentation, co-morbid factors, operative techniques, and perioperative morbidity and mortality. RESULTS: The authors found a significant decrease in operative morbidity, median perioperative transfusion, and length of hospital stay in the latter period (1986 to 1990). The incidence of postoperative subphrenic abscess and intra-abdominal hemorrhage was significantly lower during this period. Operative mortality rate was similar for both periods, 4.9% and 1.2%, respectively (p > 0.05). CONCLUSION: Hepatic resection for malignant disease currently can be performed with a low morbidity and mortality in the hands of trained and experienced hepatic surgeons; operative risks of hepatic resection should not deter its application in the treatment of primary and metastatic malignant disease of the liver.     

Compressive radial nerve palsy induced by military shooting training: clinical and electrophysiological study.

Ten recruited soldiers developed acute left wrist drop and numbness on the back of the thumb after a three hour military shooting training. Neurological examination disclosed decreased muscle power (0-2/5) of left wrist dorsiflexion, hypalgesia and hypaesthesia on the radial side of the left hand, and diminished brachioradialis reflex. Electrophysiological studies showed prolonged distal latency, reduced amplitude and slowness of left radial nerve motor conduction velocity between the axilla and elbow. Electromyography (EMG) revealed fibrillation potentials at rest, polyphasic motor unit and an incomplete interference pattern at volition over the extensor digitorum communis and brachioradialis. Nine patients recovered completely clinically and electrophysiologically between nine and 12 weeks after the onset of the palsy. Sensation recovered faster than the weakness. One patient failed to recover after three months, possibly because of the longer duration of nerve compression. Longer nerve compression time and sustained, decreased muscle power with signs of active denervation in EMG are indicators of poor prognosis.