Recapitulation of the cellular xeroderma pigmentosum-variant phenotypes using short interfering RNA for DNA polymerase H

The lesion-specific DNA polymerase POLH gene is mutated in xeroderma pigmentosum variant (XP-V) patients who exhibit an increased skin cancer incidence from UV exposure. Normal cells in which POLH expression was reduced using short interfering RNAs (siRNAs) were compared with the XP-V cellular phenotype that results from naturally occurring inactivating mutations. Stable clones expressing siRNA had partially reduced POLH protein levels, and intermediate levels of UV sensitivity and S phase checkpoint activation, but similar levels of Mre11 foci as in XP-V cells. Therefore, suppression of POLH expression levels by siRNA recapitulates most of the phenotypes seen in cells from XP-V patients with inactivating mutations in POLH.     

Educating students with TBI: themes and recommendations

Ten educational consultants and researchers, each with extensive experience working with children with traumatic brain injury (TBI) in school settings, identified seven themes related to serving this population in public schools. These themes are discussed under the headings (1) incidence of TBI and prevalence of persistent educational disability, (2) diversity and central tendencies within the population, (3) assessment, (4) intervention and support in school settings, (5) training and support for educators, (6) intervention and support for families, and (7) systems change and flexibility. For each theme, a set of recommendations is provided, forming an educational research and policy agenda for pediatric TBI.     

Factors that influence formation of B cell repertoire

V, D, and J gene segments rearrange at different frequencies in vivo. In my laboratory, we are interested in determining the reasons for this unequal rearrangement of V genes during B cell development, and also in gaining insights into the mechanisms that control recombination. Every V, D, and J gene segment is flanked on its recombining side(s) by a recombination signal sequence (RSS), which is composed of a conserved heptamer and nonamer, separated by a spacer of conserved length. In this article, we summarize data showing that in many cases the RSS can account for differences in recombination frequencies observed in vivo. The approach that we use is to determine the frequency of initial rearrangement of the V genes in vivo. The RSSs of two V genes are then placed into a competition recombination substrate to determine the relative frequency with which the two RSSs recombine. In one example, we have shown that a single base pair polymorphism in the RSS of a Vκ gene may play a major role in susceptibility ot Haemophilus influenzae type b infection.     

脐部给药的多塞平栓研制及应用

目的：研制透皮制剂多塞平栓,考察其治疗各型急、慢性荨麻疹的临床疗效。方法：多塞平以甘油明胶为质,氮酮为促透剂,制成栓剂,经脐部给药,观察５０个病例,与口服多塞平片作对照,观察临床疗效。结果：多塞平栓治疗各型急、慢性荨麻疹,总有效率为９４．０％,经统计学分析,Ｐ〈０．０５,差异具显著性。结论：本品制备工艺可行,疗效确切,用药剂量小,无副作用,具有进一步研究、开发的价值。     

Estimating the acoustic reflex threshold from wideband measures of reflectance, admittance, and power.

OBJECTIVE: A method was developed to estimate the contralateral acoustic reflex threshold using shifts in wideband energy reflectance, admittance magnitude and power. DESIGN: In the first experiment contralateral reflex thresholds for a noise activator were estimated on three adult participants using reflectance, admittance and power measurements at frequencies from 250 to 8000 Hz. The reflex threshold was defined using a magnitude and a correlation technique, both having the property of examining the pattern of the reflex-induced shift across a fairly broad frequency range (250 to 2000 Hz). In the second experiment, the magnitude method was modified to include an F test for the comparison of the magnitude of reflex-induced shifts in reflectance, admittance and power relative to response differences in a no-activator baseline condition. Data from four additional participants then were analyzed across a broader frequency range using a method that combined magnitude and correlation methods of estimating reflex thresholds. RESULTS: Acoustic reflex thresholds were obtained using reflectance, admittance and power-level measures in all subjects in both experiments. Individual reflex threshold estimates were as much as 24 dB lower than with the clinical system, with an average of approximately 14 dB lower for the three participants in the first experiment, and approximately 18 dB lower for the four participants in the second experiment. CONCLUSIONS: Wideband measures of reflectance, admittance and power were successfully used to estimate acoustic reflex thresholds in seven participants. A reflex threshold test was devised based on the magnitude of the response shift in the presence of a contralateral activator, and the similarity of the response shift spectra across frequency between successive activator levels. Across all participants in the study, the new test yielded a more sensitive measure of the acoustic reflex threshold than the clinical method. This finding has both clinical and theoretical implications for the study of the acoustic reflex.     

Safety of low anterior resection in the presence of chronic radiation changes in dogs

Thirty mongrel dogs underwent 4000- or 5000-rad single treatment orthovoltage irradiation to the pelvis according to the nominal standard dose equation. Following a resting period of six months, 21 dogs were randomized to low anterior resection with either stapled or hand-sewn anastomoses. Anastomotic leaks were evaluated on clinical and radiographic grounds. The radiographic leak rate was 81 percent for sutured and 0 percent for stapled anastomoses. The clinical leak rate was 18 percent for sutured and 0 percent for stapled anastomoses. The difference between the 4000- and 5000-rad groups was not significant. The data suggest that late effects of irradiation do not preclude the safe construction of low anterior anastomoses, and that the circular stapling device is superior to hand-sewn techniques. Poster presentation at the Annual Meeting of the American Society of Colon and Rectal Surgeons, San Diego, California, May 5 to 19, 1985.     

N-(6,6-二甲基-2-庚烯-4-炔基)-N-甲基-α-取代-1-(4-取代)萘甲胺类的合成及抗真菌活性

根据氮唑类和烯丙胺类抗真菌化合物的构效关系、作用机理。设计合成了30个N-(6,6-二甲基-2-庚烯-4-炔基)-N-甲基-α-取代-1-(4-取代)萘甲胺类化合物。初步体外抑菌试验结果表明,大多数目标化合物对八种试验菌株都有不同程度的抗真菌活性。化合物Ⅰ_1a的真菌活性大致与克霉唑相当,对白念珠菌的活性明显高于naftifine和terbinafine,但对其它七种菌株的活性均不及naftifine和terbinafine;化合物Ⅲ_1a对八种试验菌株的活性均与terbinafine相当。     

The effect of the 226-Hz probe level on contralateral acoustic stapedius reflex thresholds

PURPOSE: The purpose of this study was to examine the effect of the 226-Hz probe level on the acoustic stapedius reflex threshold. METHOD: Contralateral reflex thresholds for a 1000-Hz pure-tone stimulus were obtained from 40 young adults with normal hearing using an experimental system at four 226-Hz probe levels (70, 75, 80, and 85 dB SPL) with a repeated measures experimental design. RESULTS: A repeated measures analysis of variance revealed that as the probe level increased over this 15-dB range, there was a mean decrease in reflex threshold of 2.5 dB SPL (p < .001), with the largest decrease for an individual participant of 12 dB. CONCLUSION: The results suggest that the level of the 226-Hz probe tone as used in clinical reflex measurements and as specified in the American National Standards Institute (1987) standard is sufficiently high to affect the acoustic reflex by facilitating its activation. The effect is small, on average, but may be of clinical significance for some individuals.