Synthesis and bioactivities of 2-oxo-naphtho (1,2-d)thiazolo(3,2-a)pyrimidine derivatives]

Synthesis and Bioactivities of Some Derivatives of Naphthol [1,2-d]thiazolo [3,2-a]pyrimidin-2-one For the investigation of structure-activity relationships, the title compounds 5a-d were synthesized. Together with the intermediate 2 they were tested on rats for their antihypertensive effect, in a mouse screening for CNS responses and on the isolated ileum of the guinea pig for their anticholinergic and antihistaminic activities.     

Mycobacterial infection of the hand: clinical features and functional results

The clinical and laboratory features of twenty-eight patients with mycobacterial infection of hand are presented and discussed. Hand function assessment in fourteen patients showed that the majority had satisfactory results. The possibility of atypical mycobacterial infection is emphasised.     

Echocardiographic diagnosis of an aortic root abscess after Mycobacterium fortuitum prosthetic valve endocarditis

A patient with an aortic root abscess complicating Mycobacterium fortuitum prosthetic endocarditis is described. The correct diagnosis had been made preoperatively by echocardiography and was confirmed subsequently at surgery.     

乳酸中毒和pH对狗肺血管张力和气体交换功能影响的实验研究

急性代谢性酸中毒对狗血管张力和气体交换功能的影响进行了研究。当滴入乳酸或盐酸造成急性代谢性酸中毒（ｐＨ７．００）时，可引起肺血管收缩，肺动脉压力明显升高，血氧饱和度下降，并且乳酸和盐酸引起的酸中毒对肺动脉平均压影响程度相似，提示肺血管收缩和肺动脉压升高的程度与血中ｐＨ值下降关系密切，而与此时血中乳酸水平的高低无关。     

Dexmedetomidine Enhances Analgesic Action of Nitrous Oxide: Mechanisms of Action

Background: Nitrous oxide and dexmedetomidine are thought to mediate analgesia (antinociception in a noncommunicative organism) via [alpha]2B- and [alpha]2A-adrenergic receptor subtypes within the spinal cord, respectively. Nitrous oxide and dexmedetomidine exert diametrically opposite effects on neuronal activity within the locus ceruleus, a pivotal site for modulation of analgesia. Because of these differences, the authors explored whether the two analgesics in combination would provide satisfactory analgesia.

Methods: The analgesic effects of nitrous oxide and dexmedetomidine given both intraperitoneally and intrathecally were evaluated using the tail-flick latency test in rats. For investigation of the interaction, rats were pretreated with dexmedetomidine, either intraperitoneally or intrathecally, immediately before nitrous oxide exposure such that peak antinociceptive effects of each drug coincided. For assessment of the effect on tolerance, dexmedetomidine was administered as tolerance to nitrous oxide developed. Expression of c-Fos was used to assess neuronal activity in the locus ceruleus.

Results: Nitrous oxide and dexmedetomidine increased tail-flick latency with an ED50 (mean +/- SEM) of 55.0 +/- 2.2% atm for nitrous oxide, 27.6 +/- 5.1 for [mu]g/kg intraperitoneal dexmedetomidine, and 2.9 +/- 0.1 [mu]g for intrathecal dexmedetomidine. Combinations of systemically administered dexmedetomidine and nitrous oxide produced an additive analgesic interaction; however, neuraxially administered dexmedetomidine interacted synergistically with nitrous oxide. Tolerance to nitrous oxide was reversed by coadministration of dexmedetomidine. Prazosin, the [alpha]1-/[alpha]2B-adrenoceptor antagonist, attenuated the analgesic effect of nitrous oxide and prevented dexmedetomidine-induced reversal of tolerance to nitrous oxide. Nitrous oxide-induced increase of neuronal activity in the locus ceruleus was reversed by dexmedetomidine.     

Acrylic resins reinforced with woven highly drawn linear polyethylene fibres. 2. Water sorption and clinical trials

The results reported in this paper are part of a continuing study of the reinforcement of acrylic denture base resins with highly drawn linear polyethylene fibres. Water sorption is significantly reduced by incorporation of these fibres, even though the water diffusion processes as such remain broadly unaffected. Clinical trials are encouraging and the reinforced dentures have been well accepted by all the patients.     

Micro-analysis of mineral saturation within enamel during lactic acid demineralization

In this study, the physicochemical factors responsible for caries-like lesion propagation were investigated by means of a micro-analytical system used to study the fluid within a lesion during a simulation of the decay process. Four 500-microns-thick serial sections prepared from a single human molar were mounted between glass plates with only the natural surface of the tooth exposed. Microwells were then drilled into sound and pre-existing carious regions of the section through one of the plates. These microwells were then filled with fluid under mineral oil, and after a week of equilibration, the natural surface of the section was exposed to a lesion-producing fluid. The concentrations of calcium, phosphate, and hydrogen ions of the fluid in the wells were then followed as a function of time as the lesion advanced. The results of this study, in which lactic acid was used to demineralize enamel, were consistent with those previously reported (Vogel et al., 1987a): The solution within the lesion remained saturated during the acid attack. Differences in initial mobilities of the calcium and phosphate and other ions, a result of the permselectivity of the enamel, increased the concentrations within the lesion and permanently changed the ratio of these ions in the lesion solution. Based on these results, we suggest that the ionic permselectivity of tooth enamel can have a profound effect on the transport of mineral from a caries lesion.     

Effect of dietary vitamin E on nitrite-treated rats

The effect of dietary vitamin E on cellular responses to nitrite was studied in rats. One-month-old male Sprague-Dawley rats were fed a basal vitamin E-deficient diet with or without 100 ppm vitamin E and 1000 ppm sodium nitrite (NaNO₂) for 9 weeks. In addition to a high mortality rate, nitrite-fed rats maintained on a vitamin E-deficient diet exhibited a marked increase in liver necrosis, tubular nephrosis and myodegeneration, as well as greater biochemical and hematological alterations when compared to the control animals. No animal mortality or histopathologic lesions in any tissues were observed in rats receiving a vitamin E-supplemented diet with or without nitrite. The results suggest that depletion of vitamin E renders rats more susceptible to the adverse effect of nitrite, and that nitrite administration potentiates deficiency of vitamin E in rats.     

A new screen for anti-inflammatory agents. Estimation of rat serum acute phase alpha2-macroglobulin levels using an electroimmunoassay

Induction of alpha2-macroglobulin acute phase protein in rats by the injection of turpentine revealed strain and sex differences in the amounts of this protein detected in sera by rocket immunoelectrophoresis. Studies in vivo with a wide variety of drugs showed that non-steroidal anti-inflammatory drugs (NSAID) such as aspirin, indomethacin and BW 755C as well as colchicine, clofibrate and clozic, inhibited serum concentrations of the acute phase protein 48 h after turpentine injection. The procedure used offers a new and convenient screen for assessing NSAIDs and the method may be of value as a screen for new clozic-like compounds with anti-rheumatic activity. The possibility that the NSAIDs are inhibiting a humoral factor initiated by the inflammatory stimulus and that the humoral factor is a metabolite of arachidonic acid is discussed.