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11.
Although iron, vltamm B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB) patients Durmg a l0-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vltamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years, then annually thereafter The principal objectives of this study were to determine how readily patients who developed metabolic deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn whether the risk of developmg these deficiencies decreases over time Hemoglobin and hematocrit levels were slgnificantly decreased at all postoperative intervals in comparison to preoperative values Moreover, at each successive interval through 5 years, hemoglobin and hematocrit were decreased signifiantly compared to the preceding interval Folate levels were significantly increased compared to preoperative levels at all time intervals Iron and vltamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively Half of the low hemoglobin levels were not associated with iron deficiency Taking multivltamin supplements resulted in a lower incidence of folate deficiency but did not prevent iron or vitamin B12 deficiency Oral supplementation of iron and vitamin B12 corrected defiaencies in 43% and 81% of cases, respectively Folate deficiency was almost always corrected with multivitamins alone No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anenua Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB Conversely, iron deficiency and anemia are potentially serious problems after RYGB, particularly in younger women Hence we recommend prophylactic oral iron supplements to premenopausal women who undergo RYGB  相似文献   
12.

OBJECTIVE

To determine the biochemical recurrence (BCR) rate in patients with positive surgical margins (PSMs) on the prostate specimen who have additional negative tissue resected from that site (M+ ?), compared to patients with negative margins (M?) and those with persistent PSM (M+), as those with PSM at radical prostatectomy (RP) are at greater risk of BCR, and in some instances where suspicious tissue is noted in the prostate bed or when frozen‐section analysis shows PSM, additional tissue is resected from the suspect site of the PSM.

PATIENTS AND METHODS

Between January 1999 and June 2007, 4217 consecutive patients underwent open or laparoscopic RP with no previous radiotherapy or hormonal therapy. The median (interquartile range) follow‐up was 37.4 (21.1–60.7) months.

RESULTS

Pathological organ‐confined (OC) cancer was present in 2901 men, of whom 2659 had M?, 216 had M+, and 26 had M+ ?. Extracapsular extension (ECE) alone with no seminal vesicle or lymph node involvement was present in 843 men, of whom 657 had M?, 174 had M+ and 12 had M+ ?. For patients with OC cancer, the 36‐month actuarial BCR‐free probability was 97.9% (95% confidence interval 97.3–98.5) for M?, vs 89.0 (84.1–93.9)% for M+ vs 100% for M+ ?. For patients with ECE, the 36‐month actuarial BCR‐free probability was 83.7 (80.0–87.4)% for M? vs 73.7 (66.1–81.3)% for M+ vs 90.0 (71.4–100)% for M+ ?. The main limitation of the study was its retrospective nature, with the reason for resection of additional tissue not always well documented.

CONCLUSIONS

While the few patients with PSMs and further negative resected tissue limited the statistical analysis, it would appear that in these patients the disease behaves as in those with negative margins.  相似文献   
13.
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   
14.
Purpose : To compare clonogenic cell survival, DNA damage and chromosomal radiosensitivity in nine cervix carcinoma cell lines. Materials and methods : Initial and residual (after 24h repair) radiation-induced DNA damage was evaluated using pulsed field gel electrophoresis. Chromosome damage was measured by micronucleus (MN) induction in cytochalasin-B-induced binucleate cells. Results : Significant differences between the cell lines were obtained in the induced levels of initial damage, residual damage and MN. Values for SF2 for the nine cell lines ranged from 0.36 to 0.92. No correlation was found between clonogenic measurements of radiosensitivity and initial DNA damage dose-response slopes. However, borderline significant correlations were seen between clonogenic radiosensitivity data and the levels of residual DNA damage. There was no correlation between clonogenic radiosensitivity and the levels of radiation-induced MN. Cell lines with high levels of initial damage had high yields of MN induced by radiation and the correlation seen was significant. Conclusions : The poor correlation between the different endpoints precludes their use in a clinical setting on primary tumour samples in vitro. It may be that tumour cell lines in vitro are a poor model for tumours in vivo. Studies aimed at assessing assays for measuring tumour radiosensitivity therefore should employ clinical samples. In vitro cell line work should concentrate on unravelling the complex mechanisms involved in determining a radiosensitive or radioresistant phenotype.  相似文献   
15.
BACKGROUND: The incidence of prostate cancer in black men is 50% to 70% higher than among age-matched white men. Black men have a twofold higher mortality rate and overall tend to have higher serum prostate-specific antigen (PSA) levels than white men. To determine whether racial differences exist in men whose prostate cancer was diagnosed based solely on an elevated serum PSA level, we compared clinical and pathologic features in black and white men undergoing radical prostatectomy (RP) for clinical stage T1c prostate cancer. METHODS: We used a prospectively collected database to identify all men undergoing RP for clinical T1c prostate cancer between July 1995 and October 2000. A total of 129 consecutive men (56 black men and 73 white men) were compared for age at diagnosis, serum PSA level, biopsy Gleason score, pathologic stage, RP specimen Gleason score, incidence of lymph node metastasis, and incidence of positive surgical margins. RESULTS: Statistically significant differences were not found by race in patients' ages, serum PSA levels, biopsy Gleason score, pathologic stage, incidence of lymph node metastases, or incidence of positive surgical margins. The RP specimen Gleason score was more heterogeneous in black men than white men (P=0.02). CONCLUSIONS: Racial differences in the incidence and mortality rate of prostate cancer are well known, but differences in the clinical and pathologic features between black and white men with prostate cancer identified solely based on an elevated serum PSA level with negative results on digital rectal examination (clinical stage T1c ) have been poorly studied. Our results suggest that men with clinical stage T1c prostate cancer have similar clinical and pathologic findings regardless of race. These results suggest that early-detection programs using serum PSA testing for prostate cancer in black men potentially can result in improvements in prostate cancer outcomes in this high-risk group.  相似文献   
16.
OBJECTIVES: To prospectively compare in a contemporary and contemporaneous series the positive surgical margin (PSM) rate between laparoscopic (LRP) and retropubic (RRP) radical prostatectomy at the same institution. METHODS: Between 1 January 2003 and 30 June 2005, 1177 consecutive men with clinically localized adenocarcinoma of the prostate underwent radical prostatectomy at the same institution: 485 laparoscopically and 692 through a retropubic approach. Partin table probability of organ-confined (OC) disease was used as an index of disease aggressiveness: The PSM rate between the two approaches was compared, with adjustment for the OC probability. RESULTS: Overall both surgical approaches had a comparable PSM rate of 11.3% after LRP and 11% after RRP. In a logistic regression analysis adjusting for OC probability, there was no statistically significant difference between LRP and RRP (odds ratio [OR]: 1.156; 95% confidence interval [%95 CI], 0.792, 1.686; p=0.5). There was a statistically significant decrease over time in the rate of PSM for LRP (OR: 0.71 per 100 patients treated; %95 CI, 0.57, 0.89; p=0.003), while that of RRP was unchanged (OR: 1.06 per 100 patients treated; %95 CI, 0.94, 1.21; p=0.3; p=0.002 for interaction between change over time and procedure). CONCLUSIONS: In our institution, laparoscopic and retropubic radical prostatectomy provide comparable PSM rates for patients with clinically localized prostate cancer. The PSM rate over the study period remained unchanged in the RRP experience, indicating a mature and well-established operative technique, while that of LRP underwent a significant decrease, demonstrating that the procedure and therefore the results continued to evolve during the study.  相似文献   
17.
PURPOSE: Cavernous nerve graft is an option for men requiring bilateral cavernous nerve resection for cancer control during radical prostatectomy. We determined the success rate and identified determinants of success of bilateral cavernous nerve grafting following resection of the 2 nerves during radical prostatectomy in patients who were potent preoperatively. MATERIALS AND METHODS: We retrospectively reviewed the records of 44 consecutive patients who underwent bilateral nerve grafting from 1999 to 2004. Postoperative erectile function was defined as the achievement of erections satisfactory for intercourse with or without oral medication. We calculated cumulative erectile function recovery rates using Kaplan-Meier curves. The log rank test was used to compare variables affecting erectile function recovery with p <0.0083 considered significant after adjusting for the number of variables evaluated using the Bonferroni correction. RESULTS: The overall 5-year cumulative recovery of erectile function permitting penetration was 34% and the rate of consistent penetration was 11%. None of the analyzed variables were significantly associated with recovery of postoperative erectile function, including patient age (p = 0.3), incomplete bilateral cavernous nerve resection (p = 0.045), sural nerve grafts compared to genitofemoral or ilioinguinal nerves as donor sites (p = 0.067), post-radiation salvage radical prostatectomy (p = 0.15), neoadjuvant hormone therapy (p = 0.7) and comorbidities (p = 0.15) or medications (p = 0.4) affecting EF. CONCLUSIONS: Bilateral cavernous nerve grafts might be beneficial in select patients. A definitive answer awaits the performance of a multi-institutional, randomized, controlled trial.  相似文献   
18.
Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVE

To determine the effect of a deep and narrow pelvis on apical positive surgical margins (PSM) at radical prostatectomy (RP), controlling for other clinical and pathological variables and surgical approach, i.e. open retropubic (RRP) vs laparoscopic (LRP), as apical dissection is expected to be more challenging at RP with a prostate situated deep in a narrow pelvis.

PATIENTS AND METHODS

From July 2003 to January 2005, 512 consecutive patients with preoperative prostate magnetic resonance imaging (MRI) underwent RRP or LRP with no previous radio‐ or hormonal therapy. An additional 74 patients with preoperative MRI undergoing RP from December 2001 to June 2007 who had an apical PSM were also included, with 586 patients comprising the study population. Bony and soft‐tissue pelvic dimensions, including interspinous distance (ISD), bony (BFW) and soft tissue (SW) pelvic width, apical prostate depth (AD) and symphysis pubis angle, were measured on preoperative MRI. The pelvic dimension index (PDI), bony width index (BWI) and soft‐tissue width index (SWI) were defined as ISD/AD, BFW/AD and SW/AD, respectively. Multivariate logistic regression was used to assess the effect of pelvic dimensions on apical PSM, controlling for surgical approach and clinical and pathological variables.

RESULTS

There was no significant difference in ISD, BFW, SW or symphysis angle between patients with and without apical PSM. The AD was significantly greater in men with an apical PSM and consequently PDI, BWI and SWI were significantly lower in men with an apical PSM. Each of PDI, AD, BWI and SWI was a significant independent predictor of apical PSM, independent of surgical approach, and other clinicopathological variables. The main limitations of the study were that it was retrospective, and the relatively few patients with apical PSM.

CONCLUSIONS

Apical prostate depth is an independent risk factor for apical PSM at RP. MRI pelvimetry might allow for preoperative planning of the approach to RP.  相似文献   
19.
Men with prostate cancer are at risk for bone loss and skeletal complications throughout the course of their disease. Bone loss is prevalent in many men with prostate cancer at initial diagnosis, and initiating androgen deprivation therapy results in accelerated bone resorption, leading to bone loss and an increased risk of fracture. These men are also at high risk for disease progression and bone metastases that can result in significant skeletal morbidity, including pathologic fracture, spinal cord compression, and debilitating bone pain requiring additional therapy. Excessive osteoclast activity plays a central role in the pathophysiology of bone disease at each stage of prostate cancer disease progression. Zoledronic acid, a highly potent inhibitor of osteoclast-mediated bone resorption, has increased bone mineral density in men receiving androgen deprivation therapy and is the only bisphosphonate that has shown statistically significant reductions in skeletal morbidity in patients with bone metastases from prostate cancer. Furthermore, preclinical evidence suggests that zoledronic acid has antitumor activity in prostate cancer models. Recently, a treatment algorithm was developed by the 3rd International Consultation on Prostate Cancer recommending the use of zoledronic acid for the prevention of skeletal complications in patients with bone metastases from prostate cancer, regardless of their hormone status, and for the prevention of treatment-induced bone loss in patients without evidence of bone metastases. According to this algorithm, zoledronic acid should be considered for the prevention of skeletal morbidity in patients with prostate cancer throughout their treatment continuum.  相似文献   
20.
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   
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