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1.
Biol Reprod ; 90(6): 123, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24740597

RESUMO

We reported previously that stem cells associated with adult rat testis seminiferous tubules are able to give rise to differentiated Leydig cells in vitro. The regulatory mechanisms by which they do so, however, are uncertain. Herein, we hypothesized that the proliferation and differentiation of Leydig cell stem cells (stem Leydig cells, SLCs) depend upon locally produced factors from the seminiferous tubules. Microarray analysis revealed that platelet-derived growth factor receptor alpha (PDGFRalpha) is up-regulated and PDGFRbeta is down-regulated with postnatal differentiation of SLCs. This suggested that their ligands, PDGF-AA and PDGF-BB, respectively, might have important roles in SLC proliferation and differentiation. To test this, we developed a unique in vitro culture system in which SLCs proliferate on the surfaces of cultured seminiferous tubules largely during Week 1 of culture and their progeny subsequently differentiate to testosterone-forming Leydig cells during Weeks 2 through 4. Using this system, seminiferous tubules from adult rat testes were cultured with PDGF-AA or PDGF-BB for up to 4 wk. Both ligands stimulated SLC proliferation during the first week of culture, with PDGF-BB significantly more potent than PDGF-AA. Furthermore, PDGF-AA had a stimulatory effect on SLC differentiation from Weeks 2 through 4 of culture. In contrast, PDGF-BB, which stimulated cell proliferation during Week 1, had a significant inhibitory effect on differentiation during Weeks 2 through 4. These findings, made possible by the development of the seminiferous tubule culture system, reveal distinct roles by locally produced PDGFs in SLC regulation.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Proto-Oncogênicas c-sis/farmacologia , Túbulos Seminíferos/metabolismo , Células-Tronco Adultas/citologia , Células-Tronco Adultas/metabolismo , Fatores Etários , Animais , Becaplermina , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Intersticiais do Testículo/citologia , Masculino , Ratos Endogâmicos BN , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Túbulos Seminíferos/citologia , Túbulos Seminíferos/efeitos dos fármacos , Testículo/citologia , Testosterona/metabolismo
2.
Can Urol Assoc J ; 18(4): E105-E112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38010228

RESUMO

INTRODUCTION: Though urology attracts well-qualified applicants, students are not typically provided exposure to this smaller specialty until later in their medical education. While simulation-based training continues to supplement medical education, there is a lack of programming to teach specialty-specific procedural skills to medical students and those outside the specialty. We report a half-day simulation and didactic-based approach to increase exposure to urology to interested second-year medical students. METHODS: A half-day didactic- and simulation-based session was offered to second-year medical students (N=57). After a didactic-based overview of the specialty performed by urology providers and a surgical educator, the students participated in small-group simulations, including hands-on simulations. The students completed a post-curriculum survey measuring knowledge gains and soliciting feedback on the session. RESULTS: Students were 57.1% Caucasian, 66.7% female, with a mean age of 24.2 years; 80% stated they were potentially interested in pursuing a surgical specialty such as urology prior to the start of the session. Students reported pre- to post-curriculum gains in knowledge (mean=37%) about a career in urology and basic urologic procedures (p<0.001). Participants were also likely to recommend the curriculum to their peers (p<0.001). CONCLUSIONS: Given that exposure to urology in medical school is usually limited and offered later in training, a half-day didactic- and simulation-based experience for second-year students provides an early introduction and experience within the specialty and its common bedside procedures.

3.
Can Urol Assoc J ; 17(11): E381-E387, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37549349

RESUMO

INTRODUCTION: Options for renal drainage after percutaneous nephrolithotomy (PCNL) vary and depend primarily on surgeon preference and case considerations. In our practice, patients traditionally returned one week postoperatively to remove the stents in the office via cystoscopy; however, following uncomplicated PCNL with no plans for second-look procedure, a ureteral stent on a tether is currently removed in tandem with the Foley catheter on postoperative day 1 (POD1) prior to patient discharge. This study compared the number of postoperative events between POD1 stent removal and their longer stented counterparts. METHODS: We conducted a retrospective chart review on all patients who had undergone PCNL at our institution from January 1, 2020, to June 31, 2021. Patient demographics, operative metrics, and postoperative events (telephone calls, emergency department [ED ]/clinic visits, and complications) were recorded and compared between the two groups. RESULTS: A total of 243 patients were included in final analysis: 46% (n=111) had their stent removed on POD1 and 54% (n=132) had longer indwelling stent times. Baseline demographics were similar between the two groups. Number of telephone calls (p=0.081), ED /clinic visits (p=0.093), and complications (p=0.647) were similar between groups. There were three (1.3%) unplanned second-look procedures: two (1.8%) in the POD1 stent removal group and one (0.8%, p=0.475) in the later stent removal group. CONCLUSIONS: In this limited, retrospective study, we did not detect a difference in postoperative events or short-term complications for POD1 vs. later stent removal after uncomplicated PCNL.

4.
Proc (Bayl Univ Med Cent) ; 35(4): 441-443, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754578

RESUMO

This retrospective study evaluated the safety and efficacy of holmium laser enucleation of the prostate (HoLEP) in patients with an inflatable penile prosthesis (IPP). Five men with a preexisting IPP underwent HoLEP for obstructive lower urinary tract symptoms at Baylor Scott and White Medical Center between January 2016 and September 2020. None of the patients had preexisting prostate malignancy or urethral strictures. Minimal blood loss was seen during HoLEP, with an average length of hospital stay of 1.4 days and an average time of catheterization of 1.4 days. None of the patients had any known postoperative complications, including need for transfusions, return to the operating room for postoperative bleeding, or clot evacuation. In conclusion, there was no increased risk of perioperative or postoperative complications for HoLEP in this group compared with the general population. HoLEP appears to be a safe and efficacious method for the treatment of lower urinary tract symptoms in patients with a preexisting IPP.

5.
Proc (Bayl Univ Med Cent) ; 33(4): 554-556, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33100527

RESUMO

Holmium laser enucleation of the prostate gland (HoLEP) is an alternative to the traditional transurethral resection of the prostate, especially for large-volume prostates. One complication is urinary incontinence, which is usually stress urinary incontinence (SUI). Little data exist on surgical interventions for SUI after HoLEP. This retrospective case series examined the safety and possible efficacy of a midurethral sling (MUS) following HoLEP. Between January 2016 and February 2019, 610 HoLEPs were performed at our institution. Three (0.5%) had persistent, overly bothersome symptoms of SUI. All three underwent MUS placement with a transobturator AdVance® male sling after failed pelvic floor rehabilitation. The degree of SUI was evaluated by pad use pre-HoLEP, post-HoLEP, and post-MUS placement. Surgical times for HoLEP and MUS were evaluated. No patients were using pads for incontinence before HoLEP. The average pad use was 7 post-HoLEP and 0.3 post-MUS. The average morcellated prostate was 48 g, and surgical time was 68 min (52 for enucleation and 15 for morcellation). No complications were reported with MUS placement intraoperatively or postoperatively. MUS for persistent and bothersome SUI after HoLEP shows promise as a safe and effective surgical option.

6.
Proc (Bayl Univ Med Cent) ; 32(2): 196-198, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31191126

RESUMO

Over 500,000 men in America have a vasectomy annually; 2% to 6% of these individuals later elect to have a vasectomy reversal. Vasovasostomies are typically performed using a single- or double-layer closure, with no demonstrated difference between the two in terms of success rates. In 2005, Ho et al described a microscopic technique in which three full-thickness sutures are used and the anastomosis is reinforced with fibrin glue. At our institution, a similar technique has been used for >10 years. To describe our experience, a retrospective chart review was undertaken. Patient demographic information and operative characteristics were analyzed. In each case, fibrin glue was circumferentially applied to reinforce the anastomosis. The overall patency rate was 88.4%, and rates comparing individuals who had their vasectomy reversal within 10 years of vasectomy reached statistical significance with an odds ratio of 2.91 (P = 0.048). Median operative time was 94 minutes. Other demographic variables analyzed did not have a correlation with patency. In conclusion, our technique provides acceptable patency rates, especially with obstructive intervals of 10 years or less, while likely resulting in cost savings given the decreased operating room time and suture used.

7.
Urology ; 126: 49-53, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30654140

RESUMO

OBJECTIVE: To further analyze calcium tartrate tetrahydrate stones after a recent case report described this novel stone. Prior to this, there was only one previously reported occurrence of this stone in a human. This unusual stone composition is not tested for routinely. True prevalence and possible causes of this stone are unknown. MATERIALS/METHODS: During the previous case report, micro-CT and Fourier-transform infrared spectroscopy were used to identify a calcium tartrate tetrahydrate stone. This information was applied to urinary stones with previously unidentified compositions in the Mayo Metals laboratory database between 2010 and March 2018. Two additional stones were identified at our institution. Three patients had medical records available for analysis. RESULTS: Between 2010 and March 2018, 35 calcium tartrate stones in 25 patients were identified in the Mayo database as well as 2 at our institution (37 stones in 27 patients). Thirty stones were pure calcium tartrate with the remainder having elements of more common stones. The average age was 46.3 (±14.7) with a slightly higher incidence in females (17 vs 10). Of the 3 medical records investigated, all 3 were males (average age 48.7), and each reported consumption of an energy supplement (Spark) routinely. CONCLUSION: The true prevalence of this relatively unknown stone remains unclear and additional investigation is warranted. We believe all stone laboratories should have access to the IR spectra for calcium tartrate tetrahydrate. Attention should be paid to possible causes of this stone, particularly with relation to oral supplements, to aid with future prevention and treatment.


Assuntos
Tartaratos/análise , Cálculos Urinários/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectroscopia de Infravermelho com Transformada de Fourier , Adulto Jovem
8.
J Endourol Case Rep ; 3(1): 192-195, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29279874

RESUMO

Background: Calcium tartrate tetrahydrate has been reported as the main mineral in urinary stones in rats that have significant tartrate in their diet, but in humans, there has been only one mention of calcium tartrate stones in the form of bladder stone, and that case was in Africa. Case Presentation: Patient is a 34-year-old Caucasian male who presented with typical symptoms of nephrolithiasis. CT abd/pelvis (renal stone protocol) revealed a 2 cm nonobstructing stone of the right renal pelvis. Patient underwent an uncomplicated right percutaneous nephrolithotomy and was noted to be stone free after surgery. Stone analysis was difficult with regard to determining composition, but was finally identified as calcium tartrate tetrahydrate. Conclusion: This was an unusual case, as this is the first recorded case of a calcium tartrate tetrahydrate outside of Africa. This type of stone had only been mainly described in rat models with dl-bitartrate in their diet. Our patient was an otherwise healthy, relatively muscular individual with no obvious source for this stone other than a vitamin and amino acid supplement that he takes regularly that contains l-carnitine (as tartrate) and choline (as bitartrate and citrate). The prevalence of this stone type is presently unknown, as stone analysis laboratories have not had the ability to recognize it. Although a connection between the supplement and stone formation is conjecture at this time, we believe this necessitates further investigation.

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