Early sequelae of gunshot wounds to the spine: radiologic diagnosis

During a 6-month period, 11 consecutive patients who had delayed neurologic deterioration after sustaining a gunshot wound to the spine were prospectively evaluated clinically, radiologically, and surgically. The patients had dysesthetic burning pain in an anesthetic area, hyperhidrosis, flexor spasm, and additional motor deficit above the level of cord injury 2-22 weeks after injury. Radiologic evaluation consisted of plain radiography of the spine and metrizamide myelography followed by computed tomography. A syringomyelic cavity was found in seven patients, an arachnoid cyst in three, and osteomyelitis in one. Seven of these patients also had cord atrophy. Postoperatively, dysesthetic pain was relieved in all the patients. There was no recurrence during a 2-year follow-up. These results emphasize the need for immediate radiologic investigation in patients with gunshot wounds of the spine who have further deterioration superimposed on their initial deficit.     

Lack of correlation between maximum early follicular phase serum follicle stimulating hormone concentrations and menstrual cycle characteristics in women under the age of 35 years

The gradual increase in follicle stimulating hormone (FSH) concentrations in women approaching menopause results from the depletion of the ovarian follicular pool, a process referred to as 'ovarian ageing'. This study investigates whether variable endogenous FSH concentrations, as have been observed in normo-ovulatory young women, are related to menstrual cycle characteristics, including predictors of ovarian ageing. Serum concentrations of immunoreactive FSH, oestradiol, and inhibin-A and inhibin-B were measured, and follicular growth was assessed by transvaginal ultrasound throughout the follicular phase in 39 healthy volunteers (20-35 years) with regular menstrual cycles. Median serum FSH concentration on cycle day 3 was 5.1 IU/l (range 3.6-11.2), and median maximum follicular phase FSH was 6.2 IU/l (range 4.3-11.2), observed on cycle day 6 (range 2-15). Maximum FSH concentrations were not correlated with age or cycle length, nor with maximum inhibin-B. The number of small (<10 mm) antral follicles on cycle day 3 was 11 (range 4-21) and was not correlated with age, nor with maximum FSH. Inhibin-A remained low until a significant rise on cycle day 9 (range 3-12), which was significantly correlated with the late follicular rise in oestradiol (r = 0.56, P = 0.01). These observations indicate a lack of correlation between maximum follicular phase serum FSH concentrations and parameters of ovarian ageing in women under the age of 35 years. In addition, FSH concentrations assessed on cycle day 3 represent an underestimation of maximum early follicular phase FSH. Distinct individual differences in intra-ovarian modification of FSH action, resulting in differences in the FSH threshold for stimulation of ovarian function, may be operative.      

Near-UV/blue light-induced fluorescence in the human lens: potential interference with visual function

Irradiation of the ocular lens of numerous species by near-UV or short-visible wavelengths induces a blue-green fluorescence, which can be a source of intraocular veiling glare. Wavelengths longer than the approximately 365-nm lens absorption peak induce progressively weaker but also progressively more red-shifted fluorescence emission. The more red-shifted emission has a higher luminous efficiency and, in fact, earlier studies in this laboratory have demonstrated that the lens fluorescence in the nonhuman primate yields an approximately constant luminous efficiency when excited by equal radiant exposures over the wavelength range from 350 to 430 nm. Now, with the recent development and projected widespread use of "blue" diode lasers, a further study extending the measurements of the induced fluorescence efficiency and of the consequent veiling glare to the human lens seemed timely. The current study quantifies the fluorescence intensity induced in the human lens, both in terms of radiance and luminance, as a function of exciting light intensity, excitation wavelength, and subject age. The spatial distribution of the emitted fluorescence is also examined. These data are shown to imply that exposure to near-UV/blue wavelength sources at "safe" exposure levels (according to existing laser safety standards) can induce a veiling glare intense enough to degrade visual performance, and that the fluorescence intensity and consequent glare disruption show little dependence on subject age.     

Analysis of queries sent to PubMed at the point of care: Observation of search behaviour in a medical teaching hospital

Background

A dengue fever outbreak occured in French Guiana in 2006. The objectives were to study the value of a syndromic surveillance system set up within the armed forces, compared to the traditional clinical surveillance system during this outbreak, to highlight issues involved in comparing military and civilian surveillance systems and to discuss the interest of syndromic surveillance for public health response.

Methods

Military syndromic surveillance allows the surveillance of suspected dengue fever cases among the 3,000 armed forces personnel. Within the same population, clinical surveillance uses several definition criteria for dengue fever cases, depending on the epidemiological situation. Civilian laboratory surveillance allows the surveillance of biologically confirmed cases, within the 200,000 inhabitants.

Results

It was shown that syndromic surveillance detected the dengue fever outbreak several weeks before clinical surveillance, allowing quick and effective enhancement of vector control within the armed forces. Syndromic surveillance was also found to have detected the outbreak before civilian laboratory surveillance.

Conclusion

Military syndromic surveillance allowed an early warning for this outbreak to be issued, enabling a quicker public health response by the armed forces. Civilian surveillance system has since introduced syndromic surveillance as part of its surveillance strategy. This should enable quicker public health responses in the future.     

阿司匹林锌的研制(Ⅰ)

研究阿司匹林锌的化学合成方法。方法：以阿司匹林和硫酸锌为原料,经两步反应合成阿司匹林锌。结果得到的样品经ＩＲ、ＮＭＲ、ＭＳ等波谱分析及元素分析、热分析证明该化合物为阿司匹林锌。总收率为８０％。结论该合成方法收率稳定,合成周期短,合成路线完全可行。     

甲基莲心碱对豚鼠心房生理特性及异丙肾上腺素和Ca~(2+)量—效反应的影响

甲基莲心碱1～100μmol/L浓度依赖性地抑制豚鼠左心房收缩性,延长功能性不应期,降低兴奋性;30μmol/L甲基莲心碱能明显提高肾上腺素诱发左心房自律性的阈浓度。对异丙肾上腺素量—效反应的影响,不同于β-受体阻滞剂普萘洛尔,表现为非竞争性拮抗作用,对Ca~(2+)量—效反应的影响,与抗钙剂维拉帕米类似,呈竞争性和非竞争性双重拮抗作用。     

Comparison of violet versus red laser exposures on visual search performance in humans

Previous research suggests that the visual impairment of a violet laser is not highly localized on the retina, because the lens absorbs most short-wavelength visible light and partly retransmits it as a diffuse fluorescence at approximately 500 nm. The present study investigated whether a 405 nm violet diode laser more greatly impairs visual search performance in humans than does a 670 nm red diode laser, depending on target eccentricity. Participants had to locate a square among 15 diamonds spread throughout a visual search display while being exposed to a violet or red laser beam that was either continuous or flickering and presented either on-axis or 33 degrees off-axis. Whereas the continuous on-axis violet and red lasers had comparable effects on search performance when the target was located near the center of the beam, the violet laser disrupted processing of eccentric targets more than did the red laser. The search decrements were reduced for both lasers when the beams were flickered or presented off-axis. Both the bluish appearance and greater spatial spread of effect of the violet laser suggest that the unique impairment caused by a violet laser beam derives from its induced lens fluorescence.     

Seminal plasma alpha-glucosidase activity and male infertility

Measurement of alpha-glucosidase (alpha-GLUC) activity by means of a simple colorimetric test using a commercial kit (EpiScreen; FertiPro, Lotenhulle, Belgium) yielded results that were strongly correlated with the values obtained for the neutral iso-enzyme measured by a fluorimetric reference method (r=0.85, P=0.003, n=13). The former method was characterized by a low intra- and inter-coefficient of variation (6.6 and 4.3% respectively). Vasectomized men with azoospermia (n=27) had a significantly lower alpha-GLUC activity in semen than vasectomized men with residual spermatozoa present (n=11, P < 0.01) and men with azoospermia of primary testicular origin (n=33, P < 0.01). Receiver operating curve (ROC) analysis showed alpha-GLUC measurement to be reasonably accurate in differentiation between cases with obstructive versus testicular azoospermia at criterion value 13.5 U/l (sensitivity=82%, specificity= 70%). In cases with spermatozoa present, alpha-GLUC activity and output per ejaculate were positively correlated with sperm concentration (r=0.53 and 0.38, n=472), linear velocity (r=0.35 and 0.30, n=224), curvilinear velocity (r=0.32 and r=0.29, n=224), semen adenosine triphosphate (r=0.35 and 0.26, n=64), the concentration of 5alpha-dihydrotestosterone (r=0.31 and 0.29, n=74), and gamma-glutamyltransferase activity (r=0.62 and 0.32, n=275) in seminal plasma. The activity of alpha-GLUC was inversely correlated with ROS generation after 12-myristate, 13-acetate phorbol ester stimulation (r=-0.27, n=104), and both alpha-GLUC activity and total output were inversely correlated with the concentration of peroxidase- positive white blood cells among samples with > or =1x10(6)/ml of these cells (r=-0.30 and -0.19, n=165). It is concluded that simple photometric measurement of alpha-GLUC activity in seminal plasma reflects the functional state of the epididymis and may be helpful for the differential diagnosis of certain cases with azoospermia.