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961.
Estrogens play key roles in the development and maintenance of male reproductive function and fertility. In this review, we briefly describe the localization and function of estrogen receptors ESR1 and ESR2 (also known as ERα and ERβ, respectively) and the expression of G protein-coupled estrogen receptor-1 (GPER, formerly known as GPR30) in efferent ductules and epididymis. The efferent ductules present the highest levels of ESR1 and ESR2 in the male reproductive system, and represent a major target of estrogen action. In efferent ductules, ESR1 has a crucial role in the regulation of fluid reabsorption, and in the epididymis the receptor helps to maintain fluid osmolality and pH. ESR1 expression in the epididymal epithelium shows considerable variation among species, but differences in laboratory techniques may also contribute to this variation. Here we report that Esr1 mRNA and protein are higher in corpus than in other regions of the rat epididymis. The mRNA level for Gper was also higher in corpus. Although ESR1 is expressed constitutively in efferent ductules and down-regulated by estrogen, in the epididymis, both testosterone (T) and estradiol (E2) may regulate its expression. T and E2 are, respectively, higher and lower in the corpus than in the initial segment/caput and cauda regions. It is important to determine the expression of GPER, ESR1, androgen receptor, and their respective cofactors in specific cell types of this tissue, as well as the intracellular signaling pathways involved in efferent ductules and epididymis. These studies will help to explain the consequences of exposures to environmental endocrine disruptors and provide potential targets for the development of a male contraceptive.  相似文献   
962.
The aim of the present study was to determine the effect of low-level laser therapy (LLLT) on the expression of TNF-α and TGF-β in the tibialis anterior muscle of rats following cryoinjury. Muscle regeneration involves cell proliferation, migration and differentiation and is regulated by growth factors and cytokines. A growing body of evidence suggests that LLLT promotes skeletal muscle regeneration by reducing the duration of acute inflammation and accelerating tissue repair. Adult male Wistar rats (n = 35) were randomly divided into three groups: control group (no lesion, untreated, n = 5), cryoinjury without LLLT group (n = 15), and cryoinjury with LLLT group (n = 15). The injured region was irradiated three times a week using an AlGaInP laser (660 nm; beam spot 0.04 cm2, output power 20 mW, power density 500 mW/cm2, energy density 5 J/cm2, exposure time 10 s). Muscle remodeling was evaluated at 1, 7 and 14 days (long-term) following injury. The muscles were removed and total RNA was isolated using TRIzol reagent and cDNA synthesis. Real-time polymerase chain reactions were performed using TNF-α and TGF-β primers; GAPDH was used to normalize the data. LLLT caused a decrease in TNF-α mRNA expression at 1 and 7 days following injury and in TGF-β mRNA expression at 7 days following cryoinjury in comparison to the control group. LLLT modulated cytokine expression during short-term muscle remodeling, inducing a decrease in TNF-α and TGF-β.  相似文献   
963.

Background

Most early stage kidney cancers are renal cell carcinomas (RCCs), and most are diagnosed incidentally by imaging as small renal masses (SRMs). Indirect evidence suggests that most small RCCs grow slowly and rarely metastasize.

Objective

To determine the progression and growth rates for newly diagnosed SRMs stratified by needle core biopsy pathology.

Design, setting, and participants

A multicenter prospective phase 2 clinical trial of active surveillance of 209 SRMs in 178 elderly and/or infirm patients was conducted from 2004 until 2009 with treatment delayed until progression.

Intervention

Patients underwent serial imaging and needle core biopsies.

Measurements

We measured rates of change in tumor diameter (growth measured by imaging) and progression to ≥4 cm, doubling of tumor volume, or metastasis with histology on biopsy.

Results and limitations

Local progression occurred in 25 patients (12%), plus 2 progressed with metastases (1.1%). Of the 178 subjects with 209 SRMs, 127 with 151 SRMs had > 12 mo of follow-up with two or more images, with a mean follow-up of 28 mo. Their tumor diameters increased by an average of 0.13 cm/yr. Needle core biopsy in 101 SRMs demonstrated that the presence of RCC did not significantly change growth rate. Limitations included no central review of imaging and pathology and a short follow-up.

Conclusions

This is the first SRM active surveillance study to correlate growth with histology prospectively. In the first 2 yr, the rate of local progression to higher stage is low, and metastases are rare. SRMs appear to grow very slowly, even if biopsy proven to be RCC. Many patients with SRMs can therefore be initially managed conservatively with serial imaging, avoiding the morbidity of surgical or ablative treatment.  相似文献   
964.
965.
966.
The aim of this paper was to report a case of a patient with stage IV vaginal vault prolapse treated by laparoendoscopic single-site (LESS) sacrocolpopexy using an Alexis retractor and a surgical glove attached to three trocars through a 3.5-cm umbilical incision. Only conventional laparoscopic instruments were used for intrabdominal dissection of vagina and peritoneum. The mesh was fixed to the vaginal fornix and to the sacral periosteum from the promontory using running sutures hold in the extremities by polymer clips. The posterior peritoneum was closed over the mesh. LESS sacrocolpopexy performed with conventional instruments is a difficult but feasible and efficient technique to treat vaginal vault prolapse that respects the principles of conventional laparoscopic or open repairs. Alexis retractor associated with knotless sutures are technical options that simplify LESS reconstructive surgical maneuvers.  相似文献   
967.
C‐peptide is a cleavage product of proinsulin that acts on different type of cells, such as blood and endothelial cells. C‐peptide biological effects may be different in type 1 and type 2 diabetes. Besides, there are further evidence for a functional interaction between C‐peptide and insulin. In this way, C‐peptide has ambiguous effects, acting as an antithrombotic or thrombotic molecule, depending on the physiological environment and disease conditions. Moreover, C‐peptide regulates interaction of leucocytes, erythrocytes, and platelets with the endothelium. The beneficial effects include stimulation of nitric oxide production with its subsequent release by platelets and endothelium, the interaction with erythrocytes leading to the generation of adenosine triphosphate, and inhibition of atherogenic cytokine release. The undesirable action of C‐peptide includes the chemotaxis of monocytes, lymphocytes, and smooth muscle cells. Also, C‐peptide was related with increased lipid deposits and elevated smooth muscle cells proliferation in the vessel wall, contributing to atherosclerosis. Purpose of this review is to explore these dual roles of C‐peptide on the blood, contributing at one side to haemostasis and the other to atherosclerotic process.  相似文献   
968.
969.
Approximately 36,000 people in the United States will be diagnosed with oral or oropharyngeal cancer in 2010. In more than 90% of the cases of oral cavity and oropharyngeal cancers, histopathologic examination reveals squamous cell carcinoma (SCCA). Despite appropriate initial treatment, oral SCCA recurs in 25% to 48% of cases. Several studies have shown that most cancers recur within about 2 years after the initial treatment. Hence, close follow-up of patients is important for the timely detection of recurrences.This article discusses the types of recurrence and the surveillance and treatment of recurrent oral SCCA.  相似文献   
970.
The mandibular buccal bifurcation cyst is a cystic lesion occurring on the buccal surface of the permanent mandibular first molar in 6- to 8-year-old children. The purpose of this article was to present a case report of an 8-year-old with a radiolucent area on the permanent mandibular left first molar, with clinical, radiological, and histological characteristics compatible with the pathological entity mentioned. The treatment adopted in this case was enucleation without extraction. The patient is still under observation without any sign of recurrence.  相似文献   
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