Responses to moving slits by single units in cat striate cortex

Summary A quantitative study has been made of the responses to moving slit stimuli by single units in the cat striate cortex whose receptive fields lay within 5° of the visual axis. Special attention was given to finding the optimal stimulus parameters including slit width, length, orientation and speed. The analysis was largely based on averaged response vs. time histograms. Using the classification of simple and complex responses types, the units were further subdivided on the basis of the number of modes in the response and on the presence or absence of directional selectivity. Simple unimodal units with directional selectivity (SUDS) had the most specific stimulus requirements and nearly always had zero background activity. Complex units usually had a high level of background activity. SUDS units also showed a preference for horizontally- and vertically ****-orientated stimuli. Whenever the response survived reversal of contrast the directional selectivity remained independent of the change. Optimal stimulus speeds varied widely from unit to unit with a mean at 4°/sec: simple bimodal units and complex units tended to have higher optimal stimulus speeds and responded over a wider range of speeds than did simple unimodal units. While SUDS units with very small receptive fields tended to prefer slowly moving stimuli, in general there was no correlation between receptive field size and optimal stimulus speed.Selby Fellow of the Australian Academy of Sciences.     

Possible role of autoantibodies against nephrin in an experimental model of chronic graft-versus-host disease

Nephrin, a product of the NPHS1 gene, is a component of the slit diaphragms that are found between glomerular foot processes and is a crucial element for glomerular filtration barrier. Recently, nephrin has been focused in a number of studies of proteinuria development including various types of acquired glomerular diseases including minimal change nephrotic syndrome and membranous nephropathy. However, the precise role of nephrin in such acquired glomerular diseases is still unknown. To analyse the role of nephrin further, two kinds of anti-nephrin antibodies were raised in the rabbits and applied to an experimental mouse model of chronic graft-versus-host disease, in which (C57BL/10 x DBA/2) F1 mice developed clinically apparent severe proteinuria with significant glomerular lesions 7 weeks after parental DBA/2 cell transfer. Antibody-sandwich ELISA detected anti-nephrin antibodies during week 2 to week 6, with the peak at week 2 or week 4. Colocalization of nephrin and IgG on week 4, week 6, and week 8 was revealed by confocal microscopic analysis, suggesting that in situ immune complex formation with nephrin in glomerular lesion. Taken together, it seems to be suggested nephrin and its autoantibody have a certain role in the development of glomerular lesion in our model mice.     

眼前节OCT在闭合性眼外伤患者中的应用

目的：比较光谱域光学相干断层扫描(SD-OCT)和裂隙灯生物显微镜对闭合性眼球损伤患者眼前节病变的检测能力。

方法：这是一项观察性横断面研究。2010-01/2015-07,在惠州市中心人民医院连续招募了16名闭合性眼球损伤患者。所有患者均行完整的眼科检查,包括视力评估、非接触眼压测量和裂隙灯生物显微镜检查。采用SD-OCT检查所有损伤眼的前段。两名患者双侧眼外伤,接受双侧SD-OCT检查。记录角膜、虹膜、前房和晶状体的OCT表现,并与裂隙灯生物显微镜检查结果进行比较。

结果：所纳入的18眼均合并前房积血,且前房积血至少占前房容积的三分之一。16眼在裂隙灯生物显微镜和OCT检查中发现角膜水肿和角膜上皮损伤。OCT检查检出Descemet膜脱离(n=7),房角退缩(n=6),晶状体半脱位(n=3)和虹膜根部离断(n=3)。

结论：SD-OCT能鉴别闭式眼球损伤的特征,而在裂隙灯生物显微镜下则看不到这些特征。在闭合性眼球损伤中,SD-OCT可能优于临床检查。     

Fabrication of a Movable Obturator Following Maxillary Reconstruction with Slit‐Shaped Fenestration

Extensive maxillary resection has generally been reconstructed with free skin flaps. Because drooping of the transferred flap causes instability of the obturator prosthesis, maxillary reconstruction often incorporates a slit‐shaped oronasal fenestration. Although obturator prostheses for edentulous patients are stabilized with the help of oronasal slits, those for dentate patients are unstable because of flap mobility, resulting in a harmful lateral force exerted on the abutment teeth, causing dislodging of the denture. This report evaluates the benefits of a movable obturator prosthesis for a 60‐year‐old dentulous patient with maxillary sinus carcinoma. The patient underwent left‐sided total maxillectomy, and the defect was reconstructed with a slit‐shaped fenestration using a rectus abdominis flap. A conventional obturator prosthesis was inserted; however, drooping of the flap caused instability of the obturator, resulting in nasal regurgitation and fracture of the clasp. To solve this problem, we designed an obturator prosthesis with a movable connection consisting of a ball attachment (patrix) in the metal base and a socket (matrix) in the obturator, which acted as a stress breaker against the harmful force exerted by the flap. Application of this movable obturator prosthesis was a useful solution for a compromising situation created by the surgical procedure. No clinical disorders were observed at the 3‐year follow‐up.     

Van Herick法及河南眼科研究所改进法检查前房深度估测房角关闭的准确性研究

目的:研究Van Herick法及河南眼科研究所改进法检查前房深度估测房角关闭的准确性。方法:随机选取2018-06/2019-01于我院门诊就诊的40岁及以上患者52例100眼分别行Van Herick法和河南眼科研究所改进法检查前房深度,筛选出周边前房深度≤1/3 CT且>1/4 CT与周边前房深度≤1/4 CT人群,对Van Herick法与河南研究所改进法前房检查法结果进行一致性检验,再行房角镜检查与暗室下UBM检查分别检查周边房角是否关闭。结果:在Van Herick法估测周边前房深度≤1/3 CT且>1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为39%与43%,在河南眼科研究所改进法估测周边前房深度≤1/3 CT且>1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为46%与42%;在Van Herick法估测周边前房深度≤1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为67%与89%;在河南眼科研究所改进法估测周边前房深度≤1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为70%与100%;对Van Herick法与河南眼科研究所改进法进行一致性检验,在估测周边前房深度≤1/3CT且>1/4 CT时,Kappa值为0.85,一致性较好,在估测周边前房深度≤1/4 CT时,Kappa值为0.83,一致性较好;对房角镜检查结果及UBM检查结果进行一致性检验,在Van Herick法估测周边前房深度≤1/3 CT且>1/4 CT时,Kappa值为0.73,一致性一般,在Van Herick法估测周边前房深度≤1/4 CT时,Kappa值为0.40,一致性一般。对房角镜检查结果及UBM检查结果进行一致性检验,在河南眼科研究所改进法估测周边前房深度≤1/3 CT且>1/4 CT时,Kappa值为0.75,一致性较好,在河南眼科研究所改进法估测周边前房深度≤1/4 CT时,Kappa值为0,一致性较差。结论:Van Herick法及河南眼科研究所改进法前房深度检查在测量人群中房角关闭的具有一定的假阴性率,但准确性较高,仍适合作为估测房角关闭的初步检查方式。     

Extraction and detection of Mycobacterium leprae DNA from ZNCF-stained skin smear slides for better identification of negative skin smears

Identification of Mycobacterium leprae, which causes leprosy, is done by Ziehl Neelsen Carbol Fuchsin (ZNCF) stained slit skin smear microscopy that aids in the diagnosis and quantification of approximate bacterial load carried by the patient. We attempted M. leprae DNA extraction from 46 stained slit skin smear negative slides, using Proteinase K and SDS lysis, followed by ethanol precipitation. M. leprae specific primers (16SrRNA) were used for PCR-based amplification of DNA. We could detect M. leprae DNA in 15 (32.6%) samples. The method can be useful in the diagnosis of apparently slit skin smear negative leprosy cases.     

Dynamic changes in glypican-1 expression in dorsal root ganglion neurons after peripheral and central axonal injury

Glypican-1, a glycosyl phosphatidyl inositol (GPI)-anchored heparan sulphate proteoglycan expressed in the developing and mature cells of the central nervous system, acts as a coreceptor for diverse ligands, including slit axonal guidance proteins, fibroblast growth factors and laminin. We have examined its expression in primary sensory dorsal root ganglion (DRG) neurons and spinal cord after axonal injury. In noninjured rats, glypican-1 mRNA and protein are constitutively expressed at low levels in lumbar DRGs. Sciatic nerve transection results in a two-fold increase in mRNA and protein expression. High glypican-1 expression persists until the injured axons reinnervate their peripheral targets, as in the case of a crushed nerve. Injury to the central axons of DRG neurons by either a dorsal column injury or a dorsal root transection also up-regulates glypican-1, a feature that differs from most DRG axonal injury-induced genes, whose regulation changes only after peripheral and not central axonal injury. After axonal injury, the cellular localization of glypican-1 changes from a nuclear pattern restricted to neurons in noninjured DRGs, to the cytoplasm and membrane of injured neurons, as well as neighbouring non-neuronal cells. Sciatic nerve transection also leads to an accumulation of glypican-1 in the proximal nerve segment of injured axons. Glypican-1 is coexpressed with robo 2 and its up-regulation after axonal injury may contribute to an altered sensitivity to axonal growth or guidance cues.     

Causes and consequences of proteinuria: the kidney filtration barrier and progressive renal failure

The past few years have witnessed a major breakthrough in the understanding of the molecular mechanisms and ultrastructural changes behind the development of proteinuria. The discovery of several proteins in the glomerular podocyte and slit diaphragm, where mutations lead to disease, has revealed the importance of this cell with its diaphragm as the major filtration barrier as opposed to the glomerular basement membrane (GBM) previously ascribed this function. Furthermore, accumulating clinical as well as experimental evidence points to the harmful effects of proteinuria, irrespective of the original damage. The purpose of this review is to shed light on what we know today about the two sides of this 'coin', the causes and the consequences of proteinuria.     

进口眼科裂隙灯电路原理分析与维修

德国CARI ZEISS（蔡司）公司生产的SL115型裂隙灯是使用较为普遍的眼科设备。这篇文章根据电路图详细分析了裂隙灯的工作原理，根据故障现象准确的查出故障原因所在，对同类设备的维修具有一定的指导意义。     

Evaluation of a district-wide screening programme for diabetic retinopathy utilizing trained optometrists using slit-lamp and Volk lenses.

BACKGROUND: Debate exists about the optimum way to screen for diabetic retinopathy. Cameras produce a permanent record, but offer patients less choice about when and where to be screened. Optometrists offer flexibility but sensitivity and specificity of schemes have varied considerably, perhaps because of variability in screening methodology and that there is frequently no quality assurance programme. AIMS: To audit our district-wide (population 340000) screening programme for diabetic retinopathy against national targets: sensitivity > 80%, specificity > 95% and referral to review < 3 months. METHODS: Trained optometrists performed slit-lamp examination with Volk lenses (78 dioptre) with standardized reporting. Audit was by ophthalmologist with slit-lamp and Volk lenses through dilated pupils. RESULTS: We examined 872 eyes of 439 patients; 64% were normal, 29% background diabetic retinopathy, 7% sight-threatening eye disease (STED). Sixty-three percent of patients were seen within 6 months of the original screen. Of these, sensitivity for any retinopathy was 72%, specificity 77%, positive predictive value (PPV) 53%, negative predictive value (NPV) 88%. For STED, in this group, sensitivity was 87% and specificity 91%, PPV 30%, NPV 99%. Median interval referral to ophthalmological review was 11.5 weeks with 73% reviewed in under the 13-week target. Of those referred 25% received laser therapy. Eleven patients found to have referable eye disease at their initial screen were not referred to an ophthalmologist by their GP. CONCLUSIONS: We conclude that effective district-wide screening for diabetic retinopathy by optometrists using slit-lamp and Volk lenses is possible; however, only 36% of identified people with diabetes in the district were screened over a 4-year period.