Subtype determination of soma-dendritic α2-autoreceptors in slices of rat locus coeruleus

The aim of the study was to subclassify the soma-dendritic α₂-autoreceptors in the locus coeruleus (LC) of the rat by means of antagonists. To this end, the frequency of spontaneous action potentials was recorded extracellularly from single LC neurones in brain slices. The neurones fired spontaneously at an average rate of 1 Hz. The selective α₂-adrenoceptor agonist 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) and noradrenaline decreased the action potential discharge with IC₅₀ values of 5 and 510 nM, respectively. The concentration-inhibition curves of UK 14,304 and noradrenaline were shifted to the right by phentolamine (0.15 μM) and rauwolscine (0.15 μM) but not by prazosin (1 μM). Apparent K _d values of phentolamine were 17 nM (against UK 14,304) and 20 nM (against noradrenaline). Apparent K _d values of rauwolscine were 47 nM (against UK 14,304) and 70 nM (against noradrenaline). (+)-Oxaprotiline (1 μM) suppressed the firing of the neurones within 10 to 33 min. In the continued presence of oxaprotiline, phentolamine and rauwolscine restored firing with EC₅₀ values of 120 and 250 nM, respectively. Prazosin (1 μM) again was ineffective. All three antagonist affinity estimates – against UK 14,304, exogenous noradrenaline and endogenous noradrenaline (that accumulates in the extracellular space in the presence of oxaprotiline) – yield an affinity order phentolamine > rauwolscine >> prazosin, prazosin being ineffective even at a concentration of 1 μM. These findings identify the soma-dendritic α₂-autoreceptors of the LC as the rat variant of the α_2A/D-adrenoceptor, i.e. α_2D. Not only presynaptic but also soma-dendritic α₂-autoreceptors may at least predominantly be α_2A/D throughout the nervous system. Received: 3 March 1997 / Accepted: 21 April 1997     

Severely comminuted distal radial fracture as an unsolved problem: complications associated with external fixation and pins and plaster techniques

Seventy-six patients with severely comminuted distal radial fractures were treated at two institutions, of which the overwhelming majority were Frykman class VIII. Fifteen fractures were open. Thirty patients were seen at the University Hospital; 17 had pins and plaster and 13 had external fixation. Forty-six patients were seen at Kaiser Hospital; all had pins and plaster treatment. The complication rate for those with pins and plaster at the University Hospital was 53%; the complication for external fixation rate was 62%. The affiliated-hospital complication rate was 52%. All patients with ipsilateral forearm shaft and carpal fractures developed a nonunion of the carpal fracture. Few patients maintained anatomic reduction, and many had significant intra-articular malalignment. External fixation with threaded half pins did not obviate pin problems in our series. These methods may help manage severely comminuted distal radial fractures, but complications should be anticipated and alternative treatment considered, especially when ipsilateral carpal or forearm shaft fractures are present.     

Acute carpal tunnel syndrome caused by pigmented villonodular synovitis of the wrist

An 89-year-old woman developed an acute carpal tunnel syndrome secondary to hemarthrosis associated with pigmented villonodular synovitis of the wrist. Pigmented villonodular synovitis is rare in a patient of this age and is an unusual cause of carpal tunnel syndrome.     

Comminuted intraarticular fractures of the distal radius

The comminuted intraarticular fracture of the distal radius requires early, accurate reduction of the articular surfaces and sustained restoration of anatomic position. The most commonly employed methods are pins and plaster, external fixation, percutaneous pinning, and open reduction and internal fixation. There are pitfalls, advantages, and disadvantages inherent in each method. Careful preoperative analysis of individual patients and fractures determines the therapeutic options.     

Developments in treatment of primary irresectable rectal cancer

Abstract The treatment options for primary irresectable rectal cancers are discussed. Assessment of tumour stage is the first step for an appropriate choice of treatment. Following a diagnosis of rectal cancer, a vast array of diagnostic procedures is available to determine its stage, and thereby its best treatment options. From the many (new) diagnostic options the merits and drawbacks are discussed. If a diagnosis of irresectability is made, further treatment options should include radiotherapy in most cases, some aspects of timing and application, i.e. intra-operative treatment are discussed. Chemotherapy options are manifold, the results are discussed and some new options are explored.     

Comminuted distal radius fractures.

Comminuted displaced fractures of the distal end of the radius pose a significant treatment challenge. The goal of treatment is to restore functional, painless motion of the wrist and fingers. Although satisfactory results correlate to a large extent with obtaining and maintaining normal anatomy, excessive distraction and a flexed wrist position with external fixation cause more harm than good, even if the anatomy is restored.     

髁突形态与覆深度关系的研究

目的　探讨髁突形态与不同覆深度的关系。方法　选择正常者、开畸形患者、覆正常的错畸形患者和深覆畸形患者各 5 0人 ,均为 18至 2 6岁成人。应用曲面断层片研究左右两侧的髁突形态 ,分别测量并计算上部髁突高度 /升支高度比 (UCH/RH)和髁突高度 /宽度比 (TCH/CW )。将髁突形态分为四种类型 :直立型 (类A) ,前倾型 (类B) ,后倾型 (类C)和尖型 (类D)。结果　开组的上部髁突高度相对升支高度明显小于其他各组 (P <0 0 0 1)。正常组的髁突形态比较粗壮 ,高度宽度比明显小于其他各组 (P <0 0 0 1)。类A和类B属于正常髁突形态 ,占正常组的 99%。类C和类D属于异常髁突形态 ,且在开组中的比例明显高于正常覆组或深覆组。另外 ,只有开组中显示上部髁突高度两侧不对称 (P <0 0 5 )。结论　开组髁突形态与其他各组相比明显不同。     

F-19 MR imaging of glucose metabolism in the rabbit

Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging.     

A nationwide evaluation of multiple congenital abnormalities in Hungary

A population-based study of 7,049 index patients with multiple congenital abnormalities (MCA) born in Hungary during 1973-1982 was organized by the Hungarian Center for Congenital Anomaly Control. All clinically recognized syndromes and associations which were submitted (2,049) were accepted without any further follow-up. New or supplementary information was requested in the case of unspecified MCA (320). A copy of detailed necropsy records was requested from pathologists in lethal cases (2,022). Following these steps, apparent but not true instances of MCA were excluded (399), and an attempt was made to assign as many of the remainder as possible in 17 well-delineated MCA entities (900). The living index patients with severe MCA were referred where possible to the regional centers for evaluation (864). One hundred and seventy entities were identified, and seven cases were excluded as not representing MCA. In the so-called 3,393 unidentified cases for which no diagnosis was possible, the component abnormalities were tabulated according to their number. The final count was 6,643 cases with MCA, which is equivalent to a birth prevalence of 4.0 per 1,000 total births, and to 10% of recorded cases with congenital anomalies. As a result of this program the proportion of recognized syndromes and associations among children with MCA increased from 29% to 47%. The accuracy of diagnoses has improved, e.g., the occurrence of unspecified cases decreased from 4.5% to 2%. As a result of this study, the number of chromosomal (1,700), Mendelian (557), and teratogenic (104) syndromes and associations (758) was considerably greater than the initial notifications indicated.