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51.
Vector-borne infections of humans with the protozoan parasite Leishmania (L.) infantum can cause a systemic and potentially lethal disease termed visceral leishmaniasis. In the corresponding mouse model, an intravenous infection with L. infantum leads to the persistence of parasites in various organs, including bone marrow (BM). Considering the anatomical proximity between the BM and the cortical bone, we investigated whether a chronic infection with L. infantum affected bone homeostasis. Unexpectedly, chronic infection with L. infantum caused an increase in bone mass in mice. In vivo, an increased number of osteoblasts and osteocytes and a decreased maturation of osteoclasts characterized the phenotype. Confocal laser scanning fluorescence microscopy confirmed the infection of BM macrophages but also revealed the presence of parasites in osteoclasts. In vitro, mature osteoclasts took up L. infantum parasites. However, infection of osteoclast progenitors abolished their differentiation and function. In addition, secretory products of infected BM–derived macrophages inhibited the maturation of osteoclasts. Both in vitro and in vivo, infected macrophages and osteoclasts showed an enhanced expression of the anti-osteoclastogenic chemokine CCL5 (RANTES). Neutralization of CCL5 prevented the inhibition of osteoclast generation seen in the presence of culture supernatants from L. infantum-infected macrophages. Altogether, our study shows that chronic infection with Leishmania increases bone mass by inducing bone formation and impairing osteoclast differentiation and function. © 2022 American Society for Bone and Mineral Research (ASBMR).  相似文献   
52.
L. Bruch  S. Rubel  A. Kastner  K. Gellert  M. Gollasch    C. Witt 《Thorax》1998,53(7):586-587
BACKGROUND—Pituitaryadenylate cyclase activating peptides (PACAPs) are potent endotheliumindependent dilators of human coronary arteries; however, their effectson human pulmonary arteries are unknown.
Methods—Thevasorelaxant effects of PACAP27 on human pulmonary segmental arterieswere studied and the specific potassium (K+) channelregulatory mechanisms in the vasorelaxant effects were tested by meansof isometric contraction experiments.
RESULTS—PACAP27produced dose dependent relaxations of 10 µM rings preconstrictedwith prostaglandin F (PGF ) with half maximal relaxation (IC50) at 17 nM. Pretreatment of thevessels with the ATP sensitive K+ (KATP)channel blocker glibenclamide (1 µM) or with the Ca2+activated K+ (KCa) channel blockeriberiotoxin (100 nM) inhibited the PACAP27 induced relaxation.
Conclusions—Theseresults provide evidence that PACAPs are potent vasodilators of humanpulmonary arteries and that this relaxation might be mediated byopening of KATP and KCa channels.

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53.
This study investigates the effects of kyphoplasty on pain and mobility in patients with osteoporosis and painful vertebral fractures compared with conventional medical management. INTRODUCTION: Pharmacological treatment of patients with primary osteoporosis does not prevent pain and impaired activity of patients with painful vertebral fractures. Therefore, we evaluated the clinical outcome after kyphoplasty in patients with vertebral fractures and associated chronic pain for >12 months. MATERIALS AND METHODS: Sixty patients with primary osteoporosis and painful vertebral fractures presenting for >12 months were included in this prospective, nonrandomized controlled study. Twenty-four hours before performing kyphoplasty, the patients self-determined their inclusion into the kyphoplasty or control group so that 40 patients were treated with kyphoplasty, whereas 20 served as controls. This study assessed changes in radiomorphology, pain visual analog scale (VAS) score, daily activities (European Vertebral Osteoporosis Study [EVOS] score), number of new vertebral fractures, and health care use. Outcomes were assessed before treatment and at 3 and 6 months of follow-up. All patients received standard medical treatment (1g calcium, 1000 IE vitamin D(3), standard dose of oral aminobisphosphonate, pain medication, physical therapy). RESULTS: Kyphoplasty increased midline vertebral height of the treated vertebral bodies by 12.1%, whereas in the control group, vertebral height decreased by 8.2% (p = 0.001). Augmentation and internal stabilization by kyphoplasty resulted in a reduction of back pain. VAS pain scores improved in the kyphoplasty group from 26.2 +/- 2 to 44.2 +/- 3.3 (SD; p = 0.007) and in the control group from 33.6 +/- 4.1 to 35.6 +/- 4.1 (not significant), whereas the EVOS score increased in the kyphoplasty group from 43.8 +/- 2.4 to 54.5 +/- 2.7 (p = 0.031) and in the control group from 39.8 +/- 4.5 to 43.8 +/- 4.6 (not significant). The number of back pain-related doctor visits within the 6-month follow-up period decreased significantly after kyphoplasty compared with controls: mean of 3.3 visits/patient in the kyphoplasty group and a mean of 8.6 visits/patient in the control group (p = 0.0147). CONCLUSIONS: The results of this study show significantly increased vertebral height, reduced pain, and improved mobility in patients after kyphoplasty. Kyphoplasty performed in appropriately selected osteoporotic patients with painful vertebral fractures is a promising addition to current medical treatment.  相似文献   
54.

Background

Febrile urinary tract infections (fUTIs) are common after kidney transplantation (KTx); however, prospective data in a multicenter pediatric cohort are lacking. We designed a prospective registry to record data on fUTI before and after pediatric KTx.

Methods

Ninety-eight children (58 boys and 40 girls)?≤?18 years from 14 mid-European centers received a kidney transplant and completed a 2-year follow-up.

Results

Posttransplant, 38.7 % of patients had at least one fUTI compared with 21.4 % before KTx (p?=?0.002). Before KTx, fUTI was more frequent in patients with congenital anomalies of kidneys and urinary tract (CAKUT) vs. patients without (38 % vs. 12 %; p?=?0.005). After KTx, fUTI were equally frequent in both groups (48.7 % vs. 32.2 %; p?=?0.14). First fUTI posttransplant occurred earlier in boys compared with girls: median range 4 vs. 13.5 years (p?=?0.002). Graft function worsened (p?<?0.001) during fUTI, but no difference was recorded after 2 years. At least one recurrence of fUTI was encountered in 58 %.

Conclusion

This prospective study confirms a high incidence of fUTI after pediatric KTx, which is not restricted to patients with CAKUT; fUTIs have a negative impact on graft function during the infectious episode but not on 2-year graft outcome.
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55.
56.
Background Retrospective evaluation of the prognosis scores of Tokuhashi and Tomita for life expectancy in 37 consecutive patients with spinal metastases secondary to renal cancer who underwent surgery. The score of Tokuhashi, composed of six parameters, each rated from zero to two, has been proposed in 1990 for the prognostic assessment of patients with spinal metastases. In 2001, Tomita et al. created another prognostic score, composed of three parameters, growth behaviour of the primary tumor (slow, moderate and rapid) and the evidence of visceral and bony metastases. Methods Thirty-seven patients, surgically treated for vertebral metastases secondary to renal cancer were studied. The scores according to Tokuhashi and Tomita were calculated for each patient. Results Applying the Tokuhashi Score for the estimation of life expectancy of renal cancer patients with vertebral metastases was found to provide very reliable results with a statistically high significance. The analysis according to Tomita showed no correlation between predicted and real survival. The statistical analysis did not show any significance. Conclusion For surgical decisions in renal cancer patients with spinal metastases, the prognostic score of Tokuhashi appears to be much more valuable than the Tomita score.  相似文献   
57.
BACKGROUND: Living kidney donation helps to avoid or reduce the time period of dialysis and on waiting lists in patients requiring a new organ. Mini-incision donor nephrectomy (MIDN) shows to result in better clinical outcome in comparison with traditional open donor nephrectomy (ODN). This study was performed to evaluate the impact of different surgical procedures on the quality of life (QoL) in patients that underwent donor nephrectomy. METHODS: The aim of the study was to detect differences in QoL assessed with the Short Form-36 Version 2 (SF-36v2) questionnaire between MIDN (n = 34) and ODN (n = 36). Furthermore, the development of QoL from prior to surgery until one yr afterwards, as well as outcomes of QoL in comparison with norm-based scores was investigated. RESULTS: Sixty-one of 70 patients, which is 87% (MIDN: 86%, ODN: 88%) resent a whole set questionnaires. QoL was similar at all time-points (prior to surgery, one wk, three months and one yr) in both groups. A tendency of better QoL in MIDN (Bodily Pain) after one wk was detectable (p = 0.075). Physical Component Summaries (PCS) significantly decreased from prior to surgery until one wk after surgery (p = 0.001) and improved significantly until three months (MIDN: p = 0.006, ODN: p = 0.001) and also until one yr after surgery (p = 0.002). Mental Component Summaries (MCS) were stable throughout the whole investigated time period. In comparison with norm-based scores, MIDN (p = 0.005) and ODN (p = 0.001) showed significantly higher PCS prior to, lower scores one wk after (p = 0.001), similar scores three months after and better scores (MIDN: p = 0.023, ODN: 0.015) one yr after surgery. Mental Component Scores were similar in both prior to and one wk after surgery. After three months and one yr scores were significantly better in MIDN (three months: p = 0.049, one yr: p = 0.037) and ODN (three months: 0.020, one yr: 0.073). CONCLUSION: Quality of life after living donor nephrectomy is not influenced by the surgical technique. Nevertheless the standardized instrument of the SF-36v2 Health Survey is a useful, practicable and universally interpretable tool to gain and estimate recovery from surgical procedures in the perioperative period and its development thereafter.  相似文献   
58.
While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age‐related bone loss, we sham‐operated, ovariectomized, or ovariectomized and estrogen‐replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six‐month‐old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham‐operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen‐treated mice did not prevent age‐related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age‐related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham‐operated mice. As compared with cells from young mice, lin– cells from aged/sham‐operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age‐related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.  相似文献   
59.
Abstract Background: Does there exist a difference in the outcome of severely injured children and severely injured healthy adults? Methods: The data of 1,566 severely injured patients, treated between May 1998 and December 2002 in our emergency department of the University Essen/Germany, were analyzed. Patients with an injury severity score (ISS) > 24 were included in the present study. Patients younger as 18 (17) years were located to the children group c. Patients aged 18 and up to the age of 54 were included in the adult group a. Results: Fifty-four children and 252 adults met the selection criteria. ISS and the Glasgow coma scale (GCS) before intubation were not statistically different in both groups. Seriously injured children stayed significantly shorter on the intensive care unit, required significantly less ventilator days. Furthermore, the incidence of single organ failure (SOF) and multiple organ failure (MOF) was significantly lower in the children group. Mortality in the children group (29.6%) was lower than that in the adult group (33.7%). There was no death due to MOF in the children group as compared to 2.4% (n = 6) in the adults. Conclusion: The incidence of SOF and MOF was significantly lower in the children group although there was no difference in ISS, GCS and injury patterns. The prognosis of severely injured children was found to be better than those of adults. Moreover, there was no death due to MOF in the children group.  相似文献   
60.
Zusammenfassung Die Typ I-Allergien gegen Latex sind in den vergangenen Jahren zu einem zunehmenden berufsdermatologischen Problem geworden, zumal mindestens 10% der Angestellten im Gesundheitswesen betroffen sind. In der Dermatologischen Klinik der Universit?t Erlangen-Nürnberg stieg die Anzahl der j?hrlich diagnostizierten Patienten mit Latexallergien von 1989 bis 1995 auf das 12fache, wobei der Anteil der schweren, generalisierten Formen der Erkrankung von 10,7% (1989/1990) auf 44% (1994/1995) zunahm. Unter den m?glichen Ausl?sern der Latexallergie (wasserl?sliche Proteine mit Molekulargewichten von 2 bis 200 kD) sind mindestens 5 Hauptproteine mit bereits bekannter Prim?rstruktur zu berücksichtigen. Zus?tzlich gibt es Hinweise für Markerproteine, die in bestimmten Risikogruppen geh?uft zur Ausl?sung spezifischer IgE-Antik?rper führen (z.B. 46 kD-Protein in medizinischen Berufen, 14,6 kD- und 27 kD-Proteine bei Kindern mit Spina bifida). Das Vorkommen von Kreuzreaktionen zwischen Latex und unterschiedlichen Früchten (besonders Avocado, Kiwi, Banane, E?kastanie) bei 60 bis 70% der Latexallergiker ist bei der allergologischen Abkl?rung und Beratung dieser Patienten zu beachten. Wesentliche Aspekte der Prophylaxe umfassen die konsequente Umstellung medizinischer Einrichtungen auf ungepuderte Latexhandschuhe mit niedrigem Proteingehalt. Eine Zusammenstellung von OP- und Untersuchungshandschuhen, welche Angaben über die von uns ermittelten Proteinkonzentrationen (modifizierte Lowry-Methode und Hochdruck-Flüssigkeits-Chromatographie, HPLC) enth?lt, soll ein Leitfaden bei der Auswahl allergologisch geeigneter Handschuhe sein. Eingegangen am 10. August 1996 Angenommen am 21. August 1996  相似文献   
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