Astrocytes express type VIII collagen during the repair process of brain cold injury

We recognized for the first time upregulation of type VIII collagen gene expression during the repair process in the mouse brain cold injury model. Immunohistochemical staining showed that type VIII collagen expression was around the necrotic region, where reactive astrocytes are frequently observed. Cultured astrocytes demonstrated a high expression of type VIII collagen genes. TGF-beta1 enhanced the expression of both alpha1(VIII) and alpha2(VIII) genes by astrocytes in culture. Further, we tested selected biological activities of type VIII collagen, compared with those of type I, IV, and V collagens and fibronectin. Astrocytes adhered to type VIII collagen via receptors requiring metal ions. Astrocyte migration on type VIII collagen was more stimulated than that observed on the other ECM molecules. These data indicate that type VIII collagen plays an important role in glial scar formation during the repair process by astrocytes.     

Endothelial cells enhance adipose mesenchymal stromal cell‐mediated matrix contraction via ALK receptors and reduced follistatin: Potential role of endothelial cells in skin fibrosis

Abnormal cutaneous wound healing can lead to formation of fibrotic hypertrophic scars. Although several clinical risk factors have been described, the cross‐talk between different cell types resulting in hypertrophic scar formation is still poorly understood. The aim of this in vitro study was to investigate whether endothelial cells (EC) may play a role in skin fibrosis, for example, hypertrophic scar formation after full‐thickness skin trauma. Using a collagen/elastin matrix, we developed an in vitro fibrosis model to study the interaction between EC and dermal fibroblasts or adipose tissue‐derived mesenchymal stromal cells (ASC). Tissue equivalents containing dermal fibroblasts and EC displayed a normal phenotype. In contrast, tissue equivalents containing ASC and EC displayed a fibrotic phenotype indicated by contraction of the matrix, higher gene expression of ACTA2, COL1A, COL3A, and less secretion of follistatin. The contraction was in part mediated via the TGF‐β pathway, as both inhibition of the ALK4/5/7 receptors and the addition of recombinant follistatin resulted in decreased matrix contraction (75 ± 11% and 24 ± 8%, respectively). In conclusion, our study shows that EC may play a critical role in fibrotic events, as seen in hypertrophic scars, by stimulating ASC‐mediated matrix contraction via regulation of fibrosis‐related proteins.     

Effects of platelet derived growth factor (PDGF) on fibronectin (FN) production by human skin and scar fibroblasts

The fibroblast-type cell found in hypertrophic scars and keloids demonstrates an elevated fibronectin (FN) production, compared to the same type of cell in normal dermis. We wished to determine if the effects of platelet derived growth factor (PDGF) on FN production in these cell types would be equivalent or different. Cell lines were established from the dermis (reticularis) of hypertrophic scars, keloids, uninvolved normal skin adjacent to the lesions, including an assumed normal skin adjacent to a keloid (AS), and normal skin from a different uninjured patient (DS). Each parent tissue from which the cell lines originated was diagnosed histologically. Each hypertrophic scar, keloid and normal adjacent skin, with one exception, showed typical histologic findings confirming the clinical diagnosis. DS was also normal. AS, although assumed to be normal, in fact, demonstrated portions of nodules from the adjacent keloid. All cell lines were grown under standard conditions with subconfluent cells metabolically labeled for radioimmunoassays measuring FN at passage 3 (8 to 9 weeks in culture) in the absence and presence of PDGF. Significant differences in production of FN/cell and FN/PR/cell between two hypertrophic scars and their matched normal skins and for one keloid and its matched normal skin were observed. However, no significant difference was observed between the other keloid and AS, nor between the other hypertrophic scar and DS. PDGF significantly stimulated FN production in 2 of 4 NS cell lines, and in the AS cell line. By FN/cell values, 2 of 5 cell lines from the lesions were inhibited and one was increased. In terms of FN/PR/cell, 1 of 5 cell lines from the lesions was stimulated and the others showed no differences. The mixed results may be attributable to the likelihood that the cell lines represent mixed populations. This study demonstrates the importance of: 1) histological characterization of all parent tissues from which cell lines are derived, and 2) matching cell lines from lesions with cell lines from uninvolved normal dermis, in the same individual.     

准分子激光表层无痕术治疗近视患者的临床疗效分析

目的:研究准分子激光表层无痕术治疗近视患者的临床疗效。方法:选择2014年6月~2015年11月在我院进行准分子激光表层无痕术治疗的近视患者110例(198眼),根据眼屈光度数分为低(-1.00~-3.00 D)、中(-3~-6 D)、高(≥-6 D)度近视组。应用准分子激光对上皮层、前弹力层和前部基质层采取屈光性的切削,使眼球的表面稍微变平,角膜曲率进而改变。于术后复查眼部症状、上皮愈合情况、裸眼视力、矫正视力和屈光度。结果:仅少数患者于术后有不同程度的异物感,182眼(91.92%)角膜上皮在3天内愈合;术后所有患者的眼部均出现了不同程度的疼痛,但随着时间的增长逐渐好转,术后6 d疼痛感消失;与术前裸眼视力相比,三组在术后1天、1周、2周、1月和3月视力均明显升高,差异有统计学意义(P0.05);高度近视组在术后各时期的视力均明显低于低度近视组(P0.05);随着术后时间的延长,三组术后不同时间残余屈光度≤±1.00 D的百分比均有不同程度的升高,差异无统计学意义(P0.05);高度近视组在术后不同时间残余屈光度≤±1.00 D的百分比均明显低于低度近视组(P0.05);所有患者均无严重并发症发生,在随访期间无一例发生高眼压。结论:准分子激光表层无痕术能做到角膜无创口,有较高的预测性、安全性及有效性,且术后并发症少,有较好的应用前景。     

Rewired glycosylation activity promotes scarless regeneration and functional recovery in spiny mice after complete spinal cord transection

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Californian mixed-conifer forests under unmanaged fire regimes in the Sierra San Pedro Mártir, Baja California, Mexico

Aim This study appraises historical fire regimes for Californian mixed‐conifer forests of the Sierra San Pedro Mártir (SSPM). The SSPM represents the last remaining mixed‐conifer forest along the Pacific coast still subject to uncontrolled, periodic ground fire. Location The SSPM is a north–south trending fault bound range, centred on 31°N latitude, 100 km SE of Ensenada, Baja California. Methods We surveyed forests for composition, population structure, and historical dynamics both spatially and temporally over the past 65 years using repeat aerial photographs and ground sampling. Fire perimeter history was reconstructed based on time‐series aerial photographs dating from 1942 to 1991 and interpretable back to 1925. A total of 256 1‐ha sites randomly selected from aerial photographs were examined along a chronosequence for density and cover of canopy trees, density of snags and downed logs, and cover of non‐conifer trees and shrubs. Twenty‐four stands were sampled on‐the‐ground by a point‐centred quarter method which yielded data on tree density, basal area, frequency, importance value, and shrub and herb cover. Results Forests experience moderately intense understory fires that range in size to 6400 ha, as well as numerous smaller, low intensity burns with low cumulative spatial extent. SSPM forests average 25–45% cover and 65–145 trees per ha. Sapling densities were two to three times that of overstory trees. Size‐age distributions of trees ≥ 4 cm dbh indicate multi‐age stands with steady‐state dynamics. Stands are similar to Californian mixed conifer forests prior to the imposition of fire suppression policy. Livestock grazing does not appear to be suppressing conifer regeneration. Main conclusions Our spatially‐based reconstruction shows the open forest structure in SSPM to be a product of infrequent, intense surface fires with fire rotation periods of 52 years, rather than frequent, low intensity fires at intervals of 4–20 years proposed from California fire‐scar dendrochronology (FSD) studies. Ground fires in SSPM were intense enough to kill pole‐size trees and a significant number of overstory trees. We attribute long fire intervals to the gradual build‐up of subcontinuous shrub cover, conifer recruitment and litter accumulation. Differences from photo interpretation and FSD estimates are due to assumptions made with respect to site‐based (point) sampling of fire, and nonfractal fire intensities along fire size frequency distributions. Fire return intervals determined by FSD give undue importance to local burns which collectively use up little fuel, cover little area, and have little demographic impact on forests.     

A portable,remote‐controlled nest‐box trap

Many researchers catch adult birds at nest boxes using a vertical prop that supports a horizontal flap that drops down when an adult enters to feed nestlings. Because the prop is visible, some birds may be too wary to enter nest boxes, or they may dislodge the prop when they lean in; either way, they are not captured. We describe a remote‐controlled nest‐box trap that has the advantages of portability and being invisible to adults delivering food to nestlings. A receiver is installed on the ceiling of a nest box, the receiver is connected to a spring‐loaded flap that is triggered remotely with a transmitter from > 30 m away, and the flap drops down to cover the box entrance. In 2017 and 2018, our remote‐controlled traps did not increase the likelihood of capturing female Tree Swallows (Tachycineta bicolor), but did improve the likelihood of capturing males. We captured 16 male Tree Swallows in 30 attempts (53.3%) using our remote‐controlled trap compared to only 41 captures of males in 139 attempts (29.5%) with prop traps. In addition, whereas prop traps required an average of ~ 50 min to capture adults in successful attempts, our trap required only ~ 25 min. These results suggest that the savings in time for field researchers using our remote‐controlled trap can be substantial, with the added ethical benefit of reducing the amount of time that nestlings are not being fed. Our remote‐controlled trap is also economical to construct, requiring ~ $60 USD for parts and < 3 h to build.     

Outcome of a multimodal therapy of a recurrent adenocarcinoma arising from Caesarean section scar endometriosis—A case report

Background

Endometriosis occurring in surgical scars is a well-described entity. Malignant transformation of endometriosis is a rare event, with most cases belonging to adenocarcinoma. The initial surgical treatment is a method of choice. Due to lack of therapeutic recommendations, adjuvant therapy and recurrence management are a great challenge for oncologists.

Aim

The aim of this paper was to present a long-term survival as the outcome of multimodal therapy in the patient with recurrent adenocarcinoma arising from Caesarean section scar endometriosis.

Case

We present the case of a woman with recurrent adenocarcinoma arising from Caesarean section scar endometriosis. The disease was first diagnosed in September 1997 at age 43. The patient underwent abdominal hysterectomy with tumour excision. Due to a local recurrence after 4 years, tumour excision with abdominal wall repair using a plastic mesh, regional lymphadenectomy, bilateral salpingo-ovariectomy and adjuvant radiotherapy for the pelvic region with local boost were performed; in addition hormontherapy with medroxyprogesterone was started. Because of a recurrent pelvic tumour, chemotherapy, further local palliative radiotherapy and brachytherapy were administered. Subsequently distant metastases in bilateral axillary lymph nodes were diagnosed and palliative radiotherapy was performed. The patient died of morbus neoplasmaticus generalisatus in September 2008. The follow-up period had been 132 months.

Conclusion

This paper is, to our knowledge, the only report in literature that presents a long-term survival as the outcome of multimodal therapy in the patient with this rare diagnosis. Further reports of new cases can help establish optimal treatment guidelines.