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21.

Objectives:

To evaluate Ki67 immunoexpression pattern in Saudi breast cancer (BC) patients and investigate any possible predictive or prognostic value for Ki67.

Methods:

This is a retrospective study designed to quantitatively assess the Ki67 proliferative index (PI) in retrieved paraffin blocks of 115 Saudi BC patients diagnosed between January 2005 and March 2015 at the Department of Pathology, King Fahd Hospital, Al Madinah Al Munawarah, Kingdom of Saudi Arabia. The Ki67 PI was correlated with individual and combined immunoprofile data of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2/neu) with their clinicopathological parameters.

Results:

Ki67 immunoreactivity was highly expressed (>25% of the tumor cells were positive) in 85 (73.9%) patients. The Ki67 PI was significantly associated with poor prognostic clinicopathological parameters including old age (p<0.02), high tumor grade (p<0.01), lymph node metastasis (p<0.001), and Her-2/neu positivity (p<0.009). However, the association with ER positivity, PR positivity, tumor size, and lymphovascular invasion were not statistically significant. The Ki67 PI was significantly associated with BC molecular subtypes that were Her2/neu positive (luminal B and HER-2) subtypes compared with the Her2/neu negative (luminal A) subtype (p<0.04).

Conclusion:

The Ki67 PI is significantly higher in Saudi BC patients comparing with the reported literature. Ki67 PI was highest in the HER-2 and luminal-B molecular subtypes. Along with other prognostic indicators, Ki67 PI may be useful in predicting prognosis and management of Saudi BC patients.Breast cancer (BC) is one of the most common malignancy in the world.1 Although in the Kingdom of Saudi Arabia (KSA), the incidence of BC is much lower than in the Western world; it is still the most common malignancy in the Saudi women. According to the Saudi Cancer registry,2 BC accounted for approximately 23% of all the newly diagnosed female cancers. An additional significant fact on BC in KSA is its special presentation; as it predominantly affects the younger population, frequently presents as higher histological grades and in advanced clinical stages.2-4 Apart from the problem of its being highly prevalent globally and locally; BC has also shown its divergent nature with regards to its clinical course, response to treatment, and prognostic outcomes. Thus, the new molecular classification of BC has emerged on the basis of biomarkers. In the initial stages, the hormones namely, the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (Her2) played their roles. It was only 15 years ago, that the molecular classification of BC was proposed by Californian scientists, initially there were 4 major classes: luminal-like, basal-like, normal-like, and Her2 positive.5 Consequently, a fifth class was added, dividing one of the major luminal class to luminal A and luminal B classes.6-8 Ki67 had been known to be an important proliferation biomarker since 1980s. It has recently become an essential component of routine biomarker profile for BC, along with ER, PR, and Her2, to assist the oncologists in delivering optimum treatment to BC patients. Its role as a poor prognostic biomarker is well established, and a number of studies have found a significant correlation between Ki67 positivity with that of histological parameters such as nuclear grades and mitotic figures.9 Recent studies have also proved its predictive role in both the antihormonal therapy and chemotherapy for the efficacy of the treatment. The aim of this study is to examine the Ki67 biomarker in the BC patients and the immunohistochemically on the paraffin embedded blocks. Subsequently, to correlate the Ki67 findings with individual and combined immunoprofile data of ER, PR, and Her2/neu, as well as with their clinicopathological parameters to identify any specific differences in our BC cases as compared with western cases. This is may be important in investigating any predictive or prognostic role of Ki67 in managing BC patients in KSA population.  相似文献   
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24.
Objectives
Conjunctivitis is a common cause of primary care and emergency department (ED) visits. There is a paucity of data in recent literature on the prevalence of pediatric bacterial conjunctivitis, and there are no evidence-based clinical guidelines for empirical treatment. The study objective was to describe clinical features most predictive of bacterial conjunctivitis.
Methods
This was a prospective study in a children's hospital ED. Conjunctival swabs for bacterial culture were obtained from patients aged 1 month to 18 years presenting with red or pink eye and/or the diagnosis of conjunctivitis.
Results
A total of 111 patients were enrolled over one year. Patients had a mean (±SD) age of 33.2 (±37.5) months, and 55% were male. Eighty-seven patients (78%) had positive bacterial cultures. Nontypeable Haemophilus influenzae accounted for 82% (71/87), Streptococcus pneumoniae for 16% (14/87), and Staphylococcus aureus for 2.2% (2/87). Five clinical variables were significantly associated with a positive bacterial culture. Regression analysis revealed that the combination of a history of gluey or sticky eyelids and the physical finding of mucoid or purulent discharge had a posttest probability of 96% (95% confidence interval = 90% to 99%). Subjective scoring by physicians for a positive culture was 50.6%.
Conclusions
Conjunctivitis in children is predominantly bacterial, with nontypeable H. influenzae being the most common organism. A history of gluey or sticky eyelids and physical findings of mucoid or purulent discharge are highly predictive of bacterial infection. Based on the above data, empirical ophthalmic antibiotic therapy may be appropriate in children presenting with conjunctivitis.  相似文献   
25.
Hypertrophic scar (HSc) contraction following burn injury causes contractures. Contractures are painful and disfiguring. Current therapies are marginally effective. To study pathogenesis and develop new therapies, a murine model is needed. We have created a validated immune‐competent murine HSc model. A third‐degree burn was created on dorsum of C57BL/6 mice. Three days postburn, tissue was excised and grafted with ear skin. Graft contraction was analyzed and tissue harvested on different time points. Outcomes were compared with human condition to validate the model. To confirm graft survival, green fluorescent protein (GFP) mice were used, and histologic analysis was performed to differentiate between ear and back skin. Role of panniculus carnosus in contraction was analyzed. Cellularity was assessed with 4′,6‐diamidino‐2‐phenylindole. Collagen maturation was assessed with Picro‐sirius red. Mast cells were stained with Toluidine blue. Macrophages were detected with F4/80 immune. Vascularity was assessed with CD31 immune. RNA for contractile proteins was detected by quantitative real‐time polymerase chain reaction (qRT‐PCR). Elastic moduli of skin and scar tissue were analyzed using a microstrain analyzer. Grafts contracted to ~45% of their original size by day 14 and maintained their size. Grafting of GFP mouse skin onto wild‐type mice, and analysis of dermal thickness and hair follicle density, confirmed graft survival. Interestingly, hair follicles disappeared after grafting and regenerated in ear skin configuration by day 30. Radiological analysis revealed that panniculus carnosus doesn't contribute to contraction. Microscopic analyses showed that grafts show increase in cellularity. Granulation tissue formed after day 3. Collagen analysis revealed increases in collagen maturation over time. CD31 stain revealed increased vascularity. Macrophages and mast cells were increased. qRT‐PCR showed up‐regulation of transforming growth factor beta, alpha smooth muscle actin, and rho‐associated protein kinase 2 in HSc. Tensile testing revealed that human skin and scar tissues are tougher than mouse skin and scar tissues.  相似文献   
26.
27.

Background

Endoscopic sclerotherapy using sodium morrhuate has been used to treat patients with weight regain after Roux-en-Y gastric bypass whose presumed etiology is loss of restriction due to gastrojejunostomy dilation. Weight loss and stability have been demonstrated in several studies with short-term follow-up evaluation.

Methods

This retrospective review evaluated all the patients who underwent sclerotherapy for a dilated gastrojejunostomy between 2007 and 2012.

Results

The study identified 48 patients with a mean follow-up period of 22 months (range 12–60 months). The mean age of these patients was 47.5 ± 10.5 years, and 92 % were women. The average weight loss from the primary procedure was 132.5 ± 54.82 lb, and the average weight regain from the lowest weight to the maximum weight before sclerotherapy was 46 ± 40.32 lb. The median number of sclerotherapy sessions was two (range 1–4). The pre-procedure mean gastrojejunostomy diameter was 20 ± 3.6 mm, and the mean volume of sodium morrhuate injected per session was 12.8 ± 3.7 ml. The average weight loss from sclerotherapy to the final documented weight was 3.17 ± 19.70 lb, which was not statistically significant. The following variables in the multivariate analysis were not associated with statistically significant weight loss: volume of sodium morrhuate, patient age, gastrojejunostomy diameter, number of sclerotherapy sessions, decrease in gastrojejunostomy diameter between the first and second sessions, and number of follow-up years. Weight stabilization or loss was achieved by 58 % of our cohort, with a mean weight loss of 15.9 ± 14.6 lb in this subgroup.

Conclusion

The long-term follow-up evaluation of patients undergoing sclerotherapy of the gastrojejunostomy for weight regain after gastric bypass showed only a marginal weight loss, which was not statistically significant in our study population, although more than 50 % of the patients achieved weight loss or stabilization.  相似文献   
28.
Photorefractive keratectomy (PRK) is considered a safe approach laser procedure with a clinical significance in correcting myopia results. PRK requires removing the whole superficial epithelium. The integrity of the epithelial basement membrane and the deposition of abnormal extracellular matrix can put the cornea in a probable situation for corneal haze formation. Mitomycin C (MMC) is applied after excimer laser ablation as a primary modulator for wound healing, limiting corneal haze formation. We aim to summarize the outcomes of MMC application after laser ablation. We searched Scopus, PubMed, Cochrane CENTRAL, and Web of Science till December 2020 using relevant keywords. The data were extracted and pooled as mean difference (MD) or risk ratio (RR) with a 95% confidence interval (CI), using Review Manager software (version 5.4). Our analysis demonstrated a statistically significant result for MMC application over the control group in terms of corneal haze formation postoperatively (RR = 0.29, 95% CI: [0.19, 0.45], P < 0.00001). Regarding corrected distance visual acuity (CDVA), no significant difference was observed between the MMC group and the control group (MD = 0.02; 95% CI: [-0.04, 0.07]; P = 0.56). Regarding the uncorrected distance visual acuity (UDVA), the analysis favored the MMC application with (MD -0.03, 95% CI: [-0.06, -0.00]; P = 0.05). There was no statistically significant increase in complications with MMC. In conclusion, MMC application after PRK is associated with a lower incidence of corneal haze formation with no statistically significant side effects. The long term effect can show improvement regarding UDVA favoring MMC. However, there is no significant effect of MMCs application regarding CDVA, and SE.  相似文献   
29.

Aim/Background

How the gubernaculum guides the testis into the scrotum remains controversial, with various proposals from passive inversion to active growth. We aimed to determine if the gubernaculum contains an area of active proliferation, such as a “progress zone” in a growing embryonic limb bud, using a fluorescent cell membrane marker, 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate [DiIC12(3)], to trace cell migration, and 5-bromodeoxyuridine (BUDR) (a thymidine analogue) as a mitotic marker.

Methods

Gubernacula were collected from neonatal male rats (n = 42, day 1-2, Sprague-Dawley) and cultured with calcitonin gene-related peptide (CGRP; 714 nmol/L). 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate-coated glass beads (diameter, 150-212 μm) were placed next to the bulb for the first 3 hours. Gubernacula were cultured for 3, 18, and 24 hours, then frozen sections cut and examined by confocal microscopy (wavelength, 549 nm). In a second experiment, pups not exposed to exogenous CGRP (n = 53, day 0, Sprague-Dawley) were injected intraperitoneally with BUDR (50 mg/kg of body weight); gubernacula were collected at 2, 48, 72, and 96 hours postinjection (PI), sectioned, and stained using immunohistochemistry to count the number of BUDR-positive cells per 100 cells (labeling index) in the bulb, cremaster, cord, and epididymis.

Results

After 24 hours' culture with CGRP, the bulb showed an oval region (diameter, 300 μm) of high fluorescence, and the cremaster region showed elongated cells migrating out of the bulb. When cultured without CGRP, the same oval region contained no fluorescence. In vivo BUDR labeling index increased in all areas until 48 hours postinjection and then decreased most rapidly in the bulb (P < .05), in the presence of endogenous CGRP from the genitofemoral nerve.

Conclusions

The rat gubernaculum contains a putative progress zone, such as in a growing limb bud, in the presence of CGRP. Cells migrate out of this zone to form cremaster muscle. We hypothesize that proliferation in the bulb elongates the gubernaculum, whereas proliferation of cremaster cells would increase gubernacular diameter. This brings to “life” the gubernaculum as an actively growing organ in contrast to the inert ligament connecting the testis to the scrotum portrayed in most anatomy textbooks.  相似文献   
30.
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