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21.
Stong  RC; Uckun  F; Youle  RJ; Kersey  JH; Vallera  DA 《Blood》1985,66(3):627-635
The monoclonal antibodies (MoAb) T101, G3.7, 35.1, and TA-1 were conjugated to intact ricin using a thioether linkage. These MoAb detect, respectively, the CD5[gp67], CD7[p41], CD2[p50], and [gp95, 170] determinants that are found in the vast majority of cases of T cell acute lymphocytic leukemia (T-ALL). The resulting immunotoxins (ITs) and an equimolar mixture of these ITs were evaluated as potential purgative reagents for autologous transplantation in T-ALL. Leukemic cell lines were used to compare the kinetics of protein synthesis inactivation mediated by each IT. The cells were treated with IT in the presence of lactose in order to block the native binding of ricin. The observed rates of protein synthesis inactivation correlated with target antigen expression detected by fluorescence-activated cell sorter analysis. Of the four ITs, T101-ricin (T101-R) exhibited the fastest rate of inactivation, followed in order by G3.7-ricin, TA-1-ricin, and 35.1-ricin. At concentrations greater than 300 ng/mL, a cocktail containing an equimolar amount of all four ITs (referred to as the four- IT cocktail) exhibited kinetics that were as fast or faster than those of T101-R. The long-term cytotoxic effects of individual ITs and the four-IT cocktail were evaluated using a sensitive clonogenic assay. Each IT was specifically cytotoxic and inhibited 1 to 4 logs of clonogenic leukemic cells at doses (300 to 600 ng/mL) that can be used clinically. The four-IT cocktail was highly cytotoxic; a concentration of 300 ng/mL inhibited greater than 4 logs of leukemic cells while sparing the majority of committed (CFU-GM, CFU-E) and pluripotent (CFU- GEMM) hematopoietic stem cells. The determination of both short-term kinetics of protein synthesis inactivation and longer-term inhibition of clonogenic growth allowed new insight into cell killing by IT. Our results suggest that ITs continue to act on clonogenic target cells for a period of three to five days. Interestingly, the four-IT cocktail was not as potent against clonogenic leukemic cells as T101-R alone, although it exhibited kinetics of protein synthesis inhibition that were as fast as those of T101-R alone. This finding suggests that internalized ITs may differ in the length of time they remain active within the cell. Our results also demonstrate the importance of using several different assays to evaluate IT reagents.  相似文献   
22.
A 31-year-old female was referred from other hospital due to migrating chest pain, mild cough, and blood-tinged sputum for three days before admission. Laboratory tests were unremarkable. Chest computed tomography revealed an elliptical necrotic mass at the left anterior mediastinum, measuring 7×3×4 cm. With the impression of mediastinal abscess or loculated empyema, thoracoscopic resection was performed. There was severe pleural adhesion around the mass. The mass could be resected by the wedge resection of the adhesed upper lobe tissue of left lung around the mass. Final pathologic diagnosis was ectopic pancreas.  相似文献   
23.

Objective

Although partial nephrectomy (PN) is the standard treatment for localized clinical T1a renal cell carcinoma (RCC), treatment of larger renal tumors is controversial. We evaluated the oncological outcomes and perioperative complications after radical and PN for RCC ≥4 cm.

Patients and methods

We retrospectively analyzed the data of 2,373 patients surgically treated for nonmetastatic RCC with clinical T1b or T2 (≥4 cm). The propensity scores for surgery type were calculated, and the partial group was matched to the radical group in a 1:3 ratio. The oncological outcomes were compared using Kaplan-Meier analysis and multivariate Cox regression models were used to identify the independent predictors of progression-free, cancer-specific, and overall survival.

Results

All differences in preoperative clinical characteristics disappeared after matching. There were no significant differences in progression-free, cancer-specific, or overall survival between the partial and radical groups in the matched cohort. The patients’ age, tumor size, cellular grade, and pathologic stage were independent predictors for all 3 survival outcomes. However, early complications (<30 d postoperative) were significantly more common in the partial group (P<0.001). In a subgroup analysis of the patients with clinical T2 stage, there were no significant differences in all 3 survival outcomes.

Conclusions

The partial and radical nephrectomy groups had equivalent oncological outcomes. Although the early complication rate was significantly higher after PN, it should be considered as a valuable treatment option even in patients with clinical T1b or higher RCC.  相似文献   
24.
In osteopetrosis, osteoclast dysfunction can lead to deafness, blindness, bone marrow failure, and death. Hematopoietic cell transplantation (HCT) is currently the only curative treatment, but outcome remains disappointing. Although a rapid progression toward HCT is detrimental to prevent further progress of disease manifestations, 70% of cases lack an HLA‐matched sibling and require alternative stem cell sources. We present two cases of osteopetrosis that successfully received an HCT with haploidentical TcRαβ‐depleted cells from one of the parents. These cases showed no further disease progression, had restoration of functional osteoclasts, and illustrate this approach to enable prompt HCT with ready available parental donors and rapid and sustained hematological, including osteoclast, recovery. © 2016 American Society for Bone and Mineral Research.  相似文献   
25.
Epidemiological observations support a positive relationship between cardiovascular diseases (CVD) and osteoporosis, where cholesterol has been indicated to be a possible link. Only a few studies have investigated the relation between lipids and BMD, but the association remains unclear. We studied the relationship between serum lipids and BMD of the calcaneus. A cross‐sectional population‐based study was performed, based on data from the Longitudinal Aging Study Amsterdam, including 620 men and 635 women, 65–88 yr of age. BMD was measured by quantitative ultrasound (QUS), velocity of sound (VOS; m/s), and broadband ultrasound attenuation (BUA; dB/MHz). Models were adjusted for age, body mass index, physical activity, smoking, alcohol, diabetes mellitus, hypertension, testosterone, and 25‐hydroxyvitamin D. No association was found between total cholesterol (TC) and QUS. Men and women in the highest quartile of high‐density lipoprotein cholesterol (HDL‐c) had a significantly lower QUS (men—VOS: β = ?20.8, p = 0.00; BUA: β = ?5.2, p = 0.02; women—VOS: β = ?18.6, p = 0.00) compared with men and women in the lowest quartile. An even stronger positive association was seen between TC/HDL‐c ratio and QUS (men—VOS: β = 21.8, p = 0.00; BUA: β = 5.5, p = 0.01; women—VOS: β = 19.2, p = 0.00; BUA: β = 3.6, p = 0.05). Our analysis shows that the lipid profile that is favorable in the prevention of CVD (i.e., high levels of HDL‐c and low TC/HDL‐c ratio) is unfavorable for QUS. These results indicate that HDL‐c levels do not explain the association between osteoporosis and CVD.  相似文献   
26.
Objectives  A paucity of data exists on actual pathology of the contemporary patients strictly categorized as having low-risk prostate cancer. We tried to identify useful preoperative predictors of Gleason score upgrading in patients who underwent radical retropubic prostatectomy (RRP) for low-risk prostate cancer diagnosed via multi-core prostate biopsy. Methods  A total of 203 patients who underwent radical RRP for low-risk prostate cancer, as defined by D’Amico et al.'s classification (clinical stage ≤T2a, biopsy Gleason sum ≤6, and PSA ≤10 ng/ml), detected via multi (≥12)-core prostate biopsy were enrolled. We reviewed patients preoperative and pathological data. Results  Among all subjects, 81 (39.9%) were upgraded to Gleason score ≥7 after RRP, whereas no downgrading was observed. In multivariate analysis, only preoperative PSA level (= 0.024) and number of positive cores (P = 0.027) were observed to be independent predictors of Gleason score upgrading following RRP. Also, Gleason core upgrading was observed to be significantly associated with extraprostatic extension of tumor (P < 0.001) and positive surgical margin (P = 0.002). Conclusions  A significant proportion of patients with low-risk prostate cancer as defined by D’Amico et al.’s classification diagnosed via multi-core prostate biopsy in contemporary period may have Gleason score upgrading following RRP. For patients with low-risk prostate cancer, preoperative PSA level and number of positive cores may be useful predictors of Gleason score upgrading, which was observed to significantly associated with other adverse pathologic features.  相似文献   
27.
Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes.  相似文献   
28.
Rosacea is a skin inflammatory condition accompanied by cutaneous signs such as oedema, flushing, erythema, telangiectasia and pustules. Generally, rosacea is triggered by ultraviolet B (UVB) exposure. When exposed to UVB, skin epidermis thickens and produces elevated levels of pro-inflammatory cytokines, especially keratinocyte-related VEGF, a potent angiogenic factor. The upregulations of VEGF expression and its secretion promote the formation of new blood vessels and exacerbates rosacea. In this study, radiofrequency (RF) irradiation reduced keratinocyte proliferation in the epidermal layer, the expressions of pro-inflammatory cytokines, angiogenesis-related inflammatory factors and VEGF in our UVB-induced model of rosacea in vitro and in vivo. RF irradiation attenuated VEGF-induced angiogenesis-associated processes such as tube formation, cell migration and endothelial cell proliferation. Notably, blood vessel densities in the skins of UVB-treated mice and rosacea patients were significantly decreased by RF irradiation. These results provide experimental and molecular evidence regarding the effectiveness of RF irradiation for the treatment of rosacea.  相似文献   
29.

Background

The differential diagnosis of common pigmented skin lesions is important in cosmetic dermatology. The computer aided image analysis would be a potent ancillary diagnostic tool when patients are hesitant to undergo a skin biopsy.

Objective

We investigated the numerical parameters discriminating each pigmented skin lesion from another with statistical significance.

Methods

For each of the five magnified digital images containing clinically diagnosed nevus, lentigo and seborrheic keratosis, a total of 23 parameters describing the morphological, color, texture and topological features were calculated with the aid of a self-developed image analysis software. A novel concept of concentricity was proposed, which represents how closely the color segmentation resembles a concentric circle.

Results

Morphologically, seborrheic keratosis was bigger and spikier than nevus and lentigo. The color histogram revealed that nevus was the darkest and had the widest variation in tone. In the aspect of texture, the surface of the nevus showed the highest contrast and correlation. Finally, the color segmented pattern of the nevus and lentigo was far more concentric than that of seborrheic keratosis.

Conclusion

We found that the subtle distinctions between nevus, lentigo and seborrheic keratosis, which are likely to be unrecognized by ocular inspection, are well emphasized and detected with the aid of software.  相似文献   
30.
PURPOSE: To compare central corneal thickness measurements obtained in unoperated eyes and eyes after myopic photorefractive keratectomy (PRK) using a rotating Scheimpflug camera (Pentacam), a scanning slit corneal topography system (Orbscan II), and ultrasonic pachymetry. METHODS: Corneal thickness was measured using Pentacam, Orbscan II, and ultrasonic pachymetry in 25 unoperated eyes (unoperated group), 24 eyes 1 to 3 months after myopic PRK (early postoperative PRK group), and 21 eyes 4 months or more after myopic PRK (late postoperative PRK group). RESULTS: In the unoperated group, corneal thickness measurements were similar for all three methods (P=.125). In the early postoperative PRK group, Orbscan measurements were thinner than Pentacam and ultrasonic measurements by a mean of 69.4 microm and 63.4 microm (P<.001 and P=.002, respectively). In the late postoperative PRK group, Orbscan measurements were thinner than Pentacam measurements by a mean of 36.0 microm (P=.017). Pentacam and ultrasonic pachymetry measurements were similar for all three groups with a mean difference of approximately 10 microm. CONCLUSIONS: Following myopic PRK, Pentacam was comparable to ultrasonic pachymetry in measuring corneal thickness, whereas Orbscan measurements were thinner.  相似文献   
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