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Background and Objective: Our aim was to develop a tool using readily available clinical parameters to predict the probability of poor urinary function following low-dose-rate brachytherapy (LDR-BT) for localized prostate cancer., Methods: Data from the multicentre, prospective Swiss LDR-BT cohort were analyzed for men treated with LDR-BT. Inclusion criteria were minimum follow-up of 3 yr or postoperative treatment with transurethral resection of the prostate (TURP). A total of 914 men were analyzed, with complete data available for 607 men. Pre-interventional variables assessed were International Prostate Symptom Score (IPSS), prostate volume (PV), maximum urinary flow rate, prostate-specific antigen, postvoid residual urine volume, and age. The primary outcome was poor urinary function after LDR-BT, defined as an IPSS-Quality of Life score >3 ("mostly dissatisfied" or worse) at 3 yr or the occurrence of TURP during follow-up. Associations were evaluated using univariable and multivariable logistic regression. Receiver operating characteristic curve analysis was also performed., Key Findings and Limitations: Poor urinary function outcomes were observed in 46 patients (5.0%). Significant predictors included pre-interventional IPSS (adjusted odds ratio [aOR] per point 1.18; p  < 0.001) and PV (aOR per ml, 1.04; p  = 0.004). Limitations of the study include potential selection bias and the absence of external validation., Conclusions and Clinical Implications: Pre-interventional IPSS and PV were significant predictors of poor urinary function after LDR-BT for prostate cancer. A risk calculator based on these parameters was developed to assist individualized treatment planning. Further studies are needed to validate these findings before they can be applied in routine clinical practice., Patient Summary: We created a tool to predict the likelihood of urinary problems after a type of radiotherapy called brachytherapy for prostate cancer. The size of the prostate and urinary symptoms before treatment were associated with poor urinary function after treatment. This tool could help doctors and patients in making informed decisions about treatment for prostate cancer., (© 2024 The Authors.)

Background and Objective: Prostate-specific antigen (PSA) remains a critical marker for prostate cancer (PCa) detection and monitoring. Recognising historical variability in PSA assays and the evolution of assay technology and calibration, this study aims to reassess interassay variability using the latest generation of five assays in a contemporary cohort of men undergoing prostate biopsy., Methods: Five different commercially available PSA assays were tested in a blood sample of 76 men before undergoing a prostate biopsy. Total PSA (tPSA) and free-to-total PSA ratio (%fPSA) were compared across assays, using Roche (Basel, Switzerland) as the benchmark, and correlated with biopsy outcome to analyse the impact on PCa diagnosis. The statistical analysis included Passing-Bablok regression and Bland-Altman plots, with a p value threshold of <0.05 for significance., Key Findings and Limitations: Among the 76 men, 28 (36.8%) were diagnosed with significant PCa (defined as International Society of Urological Pathology grade ≥2). A high correlation was observed between tPSA and %fPSA values among the different PSA assays tested ( r 2  ≥ 0.9). The Passing-Bablok analysis showed that tPSA results varied substantially among the assays, with slopes ranging between 0.78 and 1.04. Compared with the tPSA of Roche, tPSA values were on average 20.7% lower by Beckman (Oststeinbeck, Germany), 15.2% lower by Abbott (Chicago, IL, USA), 6.1% lower by Diasorin (Saluggia, Italy), and 9.6% higher by Brahms (Hennigsdorf, Germany; p  < 0.001 for all). The %fPSA values by Abbott and Brahms were higher at 15.7% and 10.6%, respectively ( p  < 0.001), while the Beckman and Diasorin values had minimal differences of -0.3% and 2.3%, respectively ( p  > 0.05). The variability across assays would have resulted in discrepancies in both the sensitivity and the specificity for tPSA and %fPSA by at least 14%, depending on the cut-offs applied., Conclusions and Clinical Implications: Despite the use of the latest PSA assays, relevant variability of tPSA and %fPSA results can be observed among different assays. There is an urgent need for standardised calibration methods and greater awareness among practitioners concerning interassay variability. Clinicians should acknowledge that clinically relevant thresholds may depend on the specific PSA assay and that ideally the same assay is applied over time for better clinical decision-making., Patient Summary: Prostate-specific antigen (PSA) is a critical marker for prostate cancer (PCa) detection and monitoring. However, significant variations were observed in the results of the latest PSA assays. Thus, standardised calibration methods and greater awareness among practitioners concerning interassay variability are needed., (© 2024 The Author(s).)

Objectives: To develop a novel biopsy prostate cancer (PCa) prevention calculator (BioPrev-C) using data from a prospective cohort all undergoing mpMRI targeted and transperineal template saturation biopsy., Materials and Methods: Data of all men who underwent prostate biopsy in our academic tertiary care center between 11/2016 and 10/2019 was prospectively collected. We developed a clinical prediction model for the detection of high-grade PCa (Gleason score ≥7) based on a multivariable logistic regression model incorporating age, PSA, prostate volume, digital rectal examination, family history, previous negative biopsy, 5-alpha-reductase inhibitor use and MRI PI-RADS score. BioPrev-C performance was externally validated in another prospective Swiss cohort and compared with two other PCa risk-calculators (SWOP-RC and PBCG-RC)., Results: Of 391 men in the development cohort, 157 (40.2%) were diagnosed with high-grade PCa. Validation of the BioPrev C revealed good discrimination with an area under the curve for high-grade PCa of 0.88 (95% Confidence Interval 0.82-0.93), which was higher compared to the other two risk calculators (0.71 for PBCG and 0.84 for SWOP). The BioPrev-C revealed good calibration in the low-risk range (0 - 0.25) and moderate overestimation in the intermediate risk range (0.25 - 0.75). The PBCG-RC showed good calibration and the SWOP-RC constant underestimation of high-grade PCa over the whole prediction range. Decision curve analyses revealed a clinical net benefit for the BioPrev-C at a clinical meaningful threshold probability range (≥4%), whereas PBCG and SWOP calculators only showed clinical net benefit above a 30% threshold probability., Conclusion: BiopPrev-C is a novel contemporary risk calculator for the prediction of high-grade PCa. External validation of the BioPrev-C revealed relevant clinical benefit, which was superior compared to other well-known risk calculators. The BioPrev-C has the potential to significantly and safely reduce the number of men who should undergo a prostate biopsy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hermanns, Wettstein, Kaufmann, Lautenbach, Kaufmann, Saba, Schmid, Hötker, Müntener, Umbehr and Poyet.)

The management of prostate cancer is undergoing rapid changes in all disease settings. Novel imaging tools for diagnosis have been introduced, and the treatment of high-risk localized, locally advanced and metastatic disease has changed considerably in recent years. From clinical and health-economic perspectives, a rational and optimal use of the available options is of the utmost importance. While international guidelines list relevant pivotal trials and give recommendations for a variety of clinical scenarios, there is much room for interpretation, and several important questions remain highly debated. The goal of developing a national consensus on the use of these novel diagnostic and therapeutic strategies in order to improve disease management and eventually patient outcomes has prompted a Swiss consensus meeting. Experts from several specialties, including urology, medical oncology, radiation oncology, pathology and nuclear medicine, discussed and voted on questions of the current most important areas of uncertainty, including the staging and treatment of high-risk localized disease, treatment of metastatic hormone-sensitive prostate cancer (mHSPC) and use of new options to treat metastatic castration-resistant prostate cancer (mCRPC).

Background: Primary flexible ureterorenoscopy (URS) and extracorporeal shock wave lithotripsy (SWL) are treatment options in patients with renal calculi of 5-15 mm., Objective: To compare effectiveness, complication rates, and pain scores between primary URS and SWL., Design Setting and Participants: Between 2011 and 2016, patients with renal calculi between 5 and 15 mm were randomized to undergo either primary URS or SWL., Outcome Measurements and Statistical Analysis: Stone-free rate and size of residual fragments assessed by computed tomography after 3 mo, complications, and pain scores were evaluated., Results and Limitations: The study was prematurely closed after randomizing 44 patients due to poor accrual. The 3-mo stone-free rate and mean residual stone size were, respectively, 61% and 1.8 mm after URS and 48% and 2.4 mm after SWL. Early post-treatment pain scores were significantly higher after URS than after SWL on day 1 (3.3 vs 1.6, p  =  0.02) and day 7 (5.2 vs 3.4, p  =  0.04), but were no longer detectable after 3 wk and 3 mo, respectively. One Clavien-Dindo grade II complication was observed after URS (5%) and SWL (4%), while one (4%) grade IIIb complication was observed after SWL., Conclusions: URS appears to be associated with higher early post-treatment discomfort, which could be associated with routine postoperative stenting. Owing to premature closure of this trial, the power was insufficient to formally compare URS and SWL; however, the present data might be informative to counsel patients about treatment outcomes and allow future meta-analyses., Patient Summary: This study was ended prematurely, but it contributes data about efficacy and side effects of different treatment options in patients with renal calculi., (© 2021 The Author(s).)

Background: The reported success rates for treatments of kidney stones with either extracorporeal shock wave lithotripsy (ESWL) or flexible ureterorenoscopy (URS) are conflicting. We aimed to compare the efficacy and safety of ESWL and URS for previously untreated renal calculi., Methods: All patients treated with ESWL or URS at our tertiary care centre between 2003 and 2015 were retrospectively identified. Patients with previously untreated kidney stones and a stone diameter of 5-20 mm were included. Stone-free, freedom from reintervention and complication rates were recorded. Independent predictors of stone-free and freedom from reintervention rates were identified by multivariable logistic regression and a propensity score-matched analysis was performed., Results: A total of 1282 patients met the inclusion criteria, of whom 999 (78%) underwent ESWL and 283 (22%) had URS. During post-operative follow-up, only treatment modality and stone size could independently predict stone-free and freedom from reintervention rates. After propensity score matching, ESWL showed significantly lower stone-free rates [ESWL (71%) versus URS (84%)] and fewer patients with freedom from reintervention [ESWL (55%) versus URS (79%)] than URS. Complications were scarce for both treatments and included Clavien Grade 3a in 0.8% versus 0% and Grade 3b in 0.5% versus 0.4% of ESWL and URS treated patients, respectively., Conclusions: Treatment success was mainly dependent on stone size and treatment modality. URS might be the better treatment option for previously untreated kidney stones 5-20 mm, with similar morbidity but higher stone-free rates and fewer reinterventions than ESWL.

[This corrects the article DOI: 10.1093/ckj/sfx151.].

Background: Intratumoral hypoxia plays an important role with regard to tumor biology and susceptibility to radio- and chemotherapy. For further investigation of hypoxia-related changes, areas of certain hypoxia must be reliably detected within cancer tissues. Pimonidazole, a 2-nitroimindazole, accumulates in hypoxic tissue and can be easily visualized using immunohistochemistry., Materials and Methods: To improve detection of highly hypoxic versus normoxic areas in prostate cancer, immunoreactivity of pimonidazole and a combination of known hypoxia-related proteins was used to create computational oxygen supply maps of prostate cancer. Pimonidazole was intravenously administered before radical prostatectomy in n = 15 patients, using the da Vinci robot-assisted surgical system. Prostatectomy specimens were immediately transferred into buffered formaldehyde, fixed overnight, and completely embedded in paraffin. Pimonidazole accumulation and hypoxia-related protein expression were visualized by immunohistochemistry. Oxygen supply maps were created using the normalized information from pimonidazole and hypoxia-related proteins., Results: Based on pimonidazole staining and other hypoxia.related proteins (osteopontin, hypoxia-inducible factor 1-alpha, and glucose transporter member 1) oxygen supply maps in prostate cancer were created. Overall, oxygen supply maps consisting of information from all hypoxia-related proteins showed high correlation and mutual information to the golden standard of pimonidazole. Here, we describe an improved computer-based ex vivo model for an accurate detection of oxygen supply in human prostate cancer tissue., Conclusions: This platform can be used for precise colocalization of novel candidate hypoxia-related proteins in a representative number of prostate cancer cases, and improve issues of single marker correlations. Furthermore, this study provides a source for further in situ tests and biochemical investigations.

Pomegranate has been shown to prolong PSA doubling time in early prostate cancer, but no data from a placebo controlled trial has been published yet. The objective of this study was to prospectively evaluate the impact of pomegranate juice in patients with prostate cancer. We conducted a phase IIb, double blinded, randomized placebo controlled trial in patients with histologically confirmed prostate cancer. Only patients with a PSA value ≥ 5ng/ml were included. The subjects consumed 500 ml of pomegranate juice or 500 ml of placebo beverage every day for a 4 week period. Thereafter, all patients received 250 ml of the pomegranate juice daily for another 4 weeks. PSA values were taken at baseline, day 14, 28 and on day 56. The primary endpoint was the detection of a significant difference in PSA serum levels between the groups after one month of treatment. Pain scores and adherence to intervention were recorded using patient diaries. 102 patients were enrolled. The majority of patients had castration resistant prostate cancer (68%). 98 received either pomegranate juice or placebo between October 2008 and May 2011. Adherence to protocol was good, with 94 patients (96%) completing the first period and 87 patients (89%) completing both periods. No grade 3 or higher toxicities occurred within the study. No differences were detected between the two groups with regard to PSA kinetics and pain scores. Consumption of pomegranate juice as an adjunct intervention in men with advanced prostate cancer does not result in significant PSA declines compared to placebo.

Forkhead box protein A1 (FOXA1) modulates the transactivation of steroid hormone receptors and thus may influence tumor growth and hormone responsiveness in prostate cancer. We therefore investigated the correlation of FOXA1 expression with clinical parameters, prostate-specific antigen (PSA) relapse-free survival, and hormone receptor expression in a large cohort of prostate cancer patients at different disease stages. FOXA1 expression did not differ significantly between benign glands from the peripheral zone and primary peripheral zone prostate carcinomas. However, FOXA1 was overexpressed in metastases and particularly in castration-resistant cases, but was expressed at lower levels in both normal and neoplastic transitional zone tissues. FOXA1 levels correlated with higher pT stages and Gleason scores, as well as with androgen (AR) and estrogen receptor expression. Moreover, FOXA1 overexpression was associated with faster biochemical disease progression, which was pronounced in patients with low AR levels. Finally, siRNA-based knockdown of FOXA1 induced decreased cell proliferation and migration. Moreover, in vitro tumorigenicity was inducible by ARs only in the presence of FOXA1, substantiating a functional cooperation between FOXA1 and AR. In conclusion, FOXA1 expression is associated with tumor progression, dedifferentiation of prostate cancer cells, and poorer prognosis, as well as with cellular proliferation and migration and with AR signaling. These findings suggest FOXA1 overexpression as a novel mechanism inducing castration resistance in prostate cancer., (Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Previously, we identified the calcium-activated nucleotidase 1 (CANT1) transcript as up-regulated in prostate cancer. Now, we studied CANT1 protein expression in a large cohort of nearly 1000 prostatic tissue samples including normal tissue, prostatic intraepithelial neoplasia (PIN), primary carcinomas, metastases, and castrate-resistant carcinomas, and further investigated its functional relevance. CANT1 displayed predominantly a Golgi-type immunoreactivity with additional and variable cytoplasmic staining. In comparison to normal tissues, the staining intensity was significantly increased in PIN lesions and cancer. In cancer, high CANT1 levels were associated with a better prognosis, and castrate-resistant carcinomas commonly showed lower CANT1 levels than primary carcinomas. The functional role of CANT1 was investigated using RNA interference in two prostate cancer cell lines with abundant endogenous CANT1 protein. On CANT1 knockdown, a significantly diminished cell number and DNA synthesis rate, a cell cycle arrest in G(1) phase, and a strong decrease of cell transmigration rate and wound healing capacity of CANT1 knockdown cells was found. However, on forced CANT1 overexpression, cell proliferation and migration remained unchanged. In summary, CANT1 is commonly overexpressed in the vast majority of primary prostate carcinomas and in the precursor lesion PIN and may represent a novel prognostic biomarker. Moreover, this is the first study to demonstrate a functional involvement of CANT1 in tumor biology., (Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Background: The oncofetal protein insulin-like growth factor II mRNA binding protein 3 (IMP3) is an important factor for cell-migration and adhesion in malignancies. Recent studies have shown a remarkable overexpression of IMP3 in different human malignant neoplasms and also revealed it as an important prognostic marker in some tumor entities. To our knowledge, IMP3 expression has not been investigated in prostate carcinomas so far., Methods: Immunohistochemical stainings for IMP3 were performed on tissue microarray (TMA) organized samples from 507 patients: 31 normal prostate tissues, 425 primary carcinomas and 51 prostate cancer metastases or castration-resistant prostate cancers (CRPC). IMP3 immunoreactivity was semiquantitatively scored and correlated with clinical-pathologic parameters including survival., Results: IMP3 is significantly stronger expressed in prostate carcinomas compared to normal prostate tissues (p < 0.0001), but did not show significant correlation with the pT-stage, the proliferation index (MIB1), preoperative serum PSA level and the margin status. Only a weak and slightly significant correlation was found with the Gleason score and IMP3 expression failed to show prognostic significance in clinico-pathological correlation-analyses., Conclusions: Although IMP3 is overexpressed in a significant proportion of prostate cancer cases, which might be of importance for novel therapeutic approaches, it does not appear to possess any immediate diagnostic or prognostic value, limiting its potential as a tissue biomarker for prostate cancer. These results might be corroborated by the fact, that two independent tumor cohorts were separately reviewed.

Spinal decompression is the most common type of spinal surgery carried out in the older patient, and is being performed with increasing frequency. Physiotherapy (rehabilitation) is often prescribed after surgery, although its benefits compared with no formal rehabilitation have yet to be demonstrated in randomised control trials. The aim of this randomised controlled trial was to examine the effects on outcome up to 2 years after spinal decompression surgery of two types of postoperative physiotherapy compared with no postoperative therapy (self-management). Hundred and fifty-nine patients (100 men, 59 women; 65 +/- 11 years) undergoing decompression surgery for spinal stenosis/herniated disc were randomised to one of the following programmes beginning 2 months post-op: recommended to "keep active" (CONTROL; n = 54); physiotherapy, spine stabilisation exercises (PT-StabEx; n = 56); physiotherapy, mixed techniques (PT-Mixed; n = 49). Both PT programmes involved 2 x 30 min sessions/week for up to 12 weeks, with home exercises. Pain intensity (0-10 graphic rating scale, for back and leg pain separately) and self-rated disability (Roland Morris) were assessed before surgery, before and after the rehabilitation phase (approx. 2 and 5 months post-op), and at 12 and 24 months after the operation. 'Intention to treat' analyses were used. At 24 months, 151 patients returned questionnaires (effective return rate, excluding 4 deaths, 97%). Significant reductions in leg and back pain and self-rated disability were recorded after surgery (P < 0.05). Pain showed no further changes in any group up to 24 months later, whereas disability declined further during the "rehabilitation" phase (P < 0.05) then stabilised, but with no significant group differences. 12 weeks of post-operative physiotherapy did not influence the course of change in pain or disability up to 24 months after decompression surgery. Advising patients to keep active by carrying out the type of physical activities that they most enjoy appears to be just as good as administering a supervised rehabilitation program, and at no cost to the health-care provider.

Purpose: To analyze the histologic features of the insertion of the medial and the lateral rectus muscles in humans., Methods: Postmortem study performed on 49 extraocular muscles from 21 subjects without known ocular disease. All muscles were obtained no longer than 8 hours after death, after consent for autopsy. Thirty-seven lateral recti muscles and 12 medial recti muscles were studied with light microscopy (hematoxylin-eosin and Goldner stains) as well as with enzyme histochemistry and immunohistochemistry, with monoclonal-human tenascin C antibody., Results: Light microscopic studies of muscle insertions of the lateral and the medial rectus muscle demonstrated muscle tissue connecting directly to the sclera without a tendon. These findings were confirmed immunohistochemically with tenascin C-antibody staining., Conclusions: Based on the results of this postmortem study in humans the term "muscle tendon" should be used with caution for the insertional area (scleromuscular junction) of the lateral and medial extraocular muscles. Light microscopy, histochemistry, and immunohistochemistry demonstrate that the tissue at the scleromuscular junction contains striated muscle with minimal connective (tendinous) tissue connecting to the sclera. To the best of the authors' knowledge, this is the first study in which enzyme histochemistry and immunohistochemistry have been used to investigate the anatomy of the insertional area (muscle-tendon-sclera junction) of the extraocular muscles in humans.

The value of range of motion (ROM) as an indicator of impairment associated with spinal problems, and in monitoring changes in response to treatment, is a controversial issue. The aim of this study was to examine the interrelationship between subjective disability (Roland-Morris scores) and objectively measured impairment (ROM), both before and in response to spinal decompression surgery, in an older group of patients with herniated lumbar disc (DH). Seventy-six individuals took part in the study: 33 patients (mean age 57 years, SD 9 years) presenting with DH and for whom decompression surgery was planned, and 43 controls (mean age 57 years, SD 7 years), with no history of back pain requiring medical treatment. In the patient group, pain intensity (leg and back; visual analog score), self-rated disability (Roland-Morris score), certain psychological attributes, and ROM of the spine (Spinal Mouse) were measured before and 2 months after decompression surgery. In addition, the patients rated the success of surgery on a 1-5 Likert scale. The pain-free control group performed only the tests of spinal mobility. Before surgery, compared with matched controls, significantly lower values were observed in the DH patients for standing lumbar lordosis (p=0.01), and for range of flexion of the lumbar spine (ROF(lumbar)) (p=0.0006), but not of the hips (ROF(hip)) (p=0.14). Roland-Morris Disability scores correlated significantly with ROF(lumbar) (r=0.61, p=0.0002), but less well with ROF(hip)(r=0.43, p=0.01). Two months after surgery, there were significant reductions in back pain and leg pain (p=0.0001) and in Roland-Morris Disability scores (p=0.019). There was also a significant decrease in the group mean values for lumbar lordosis angle (i.e., a "flatter" spine after surgery, p=0.002) and ROF(lumbar) (p=0.038). ROF(hip) showed a (nonsignificant) tendency to increase (p=0.08) towards normal control values. As a result of these two opposing changes, the range of total trunk flexion showed no significant changes from pre-surgery to 2 months post-surgery (p=0.60). On an individual basis, there was a highly significant relationship between the change in self-rated disability scores and the change in ROF(lumbar), pre-surgery- to 2 months post-surgery (r= -0.82; p<0.0001). Changes in ROF(hip) showed no such relationship (r= -0.30, p=0.10). The patients in the "poor" outcome group ("surgery didn't help"; 9%) had a significantly greater reduction in ROF(lumbar) post-surgery compared with the "good" outcome group ("surgery helped"; 91%) (p=0.04). In stepwise linear regression, the change in ROF(lumbar) was the only variable accounting for the change in self-rated disability pre-surgery to post-surgery (variables not included: pain intensity, psychological factors). The pivotal role of lumbar mobility in explaining disability emphasizes the importance of measuring lumbar and hip ranges of motion separately, as opposed to "global trunk motion." In the patient group examined, the determination of lumbar spinal mobility provides a valid, objective measure of function, that shows differences from normal matched controls, that correlates well with self-rated disability, and the changes in which correlate extremely well with subjective changes in disability following surgery.

In skeletal muscles, focal adhesion complexes (FACs) form part of the costamere, a sarcolemmal protein complex that enables lateral transfer of forces and ensures the stability of the sarcolemma. The present investigation tested whether localisation of a major assembly factor of FACs, focal adhesion kinase (FAK), to the sarcolemma parallels the known modulation of FACs by fibre type (innervation pattern) and fibre regeneration. Immunohistochemical experiments indicated that FAK is preferentially associated with the sarcolemma in a high proportion (>74 %) of the (slow-twitch) type I and (fast-twitch) type IIA fibres in normal rat soleus (N-SOL) muscle and of the type IIA fibres in extensor digitorum longus (N-EDL) muscle. In contrast, a low proportion (<15 %) of fast-twitch type IIB and type I fibres in N-EDL showed sarcolemmal FAK immunoreactivity. Cross-reinnervation of slow-twitch rat SOL muscle with the fast EDL nerve induced slow-to-fast fibre transformation and led to a significant reduction in sarcolemmal FAK immunoreactivity in type I and type IIA fibres. Transplantation of the fast EDL into the slow SOL bed with regeneration and reinnervation of the muscle by the SOL nerve (T-EDL) caused a significant increase in sarcolemmal FAK immunoreactivity in new type I and hybrid I/II fibres and a corresponding reduction in sarcolemmal FAK immunoreactivity in 'normal' IIA and IIB fibres. Conversely, sarcolemmal FAK immunoreactivity in small IIB fibres of T-EDL muscle was increased. Correspondingly, the transplanted and regenerated SOL (reinnervated by the fast EDL nerve) maintained the percentage of FAK-positive sarcolemma in the (regenerated) type I and IIA fibres. Thus, the expression and association of FAK with the sarcolemma are regulated (i) by factors that determine the fibre type and (ii) during fibre regeneration. Our data suggest that the integrity of sarcolemmal FACs is dependent on the fibre type and that FAC turnover is increased during regeneration of muscle fibres.

Mammalian skeletal muscle shows an enormous variability in its functional features such as rate of force production, resistance to fatigue, and energy metabolism, with a wide spectrum from slow aerobic to fast anaerobic physiology. In addition, skeletal muscle exhibits high plasticity that is based on the potential of the muscle fibers to undergo changes of their cytoarchitecture and composition of specific muscle protein isoforms. Adaptive changes of the muscle fibers occur in response to a variety of stimuli such as, e.g., growth and differentition factors, hormones, nerve signals, or exercise. Additionally, the muscle fibers are arranged in compartments that often function as largely independent muscular subunits. All muscle fibers use Ca(2+) as their main regulatory and signaling molecule. Therefore, contractile properties of muscle fibers are dependent on the variable expression of proteins involved in Ca(2+) signaling and handling. Molecular diversity of the main proteins in the Ca(2+) signaling apparatus (the calcium cycle) largely determines the contraction and relaxation properties of a muscle fiber. The Ca(2+) signaling apparatus includes 1) the ryanodine receptor that is the sarcoplasmic reticulum Ca(2+) release channel, 2) the troponin protein complex that mediates the Ca(2+) effect to the myofibrillar structures leading to contraction, 3) the Ca(2+) pump responsible for Ca(2+) reuptake into the sarcoplasmic reticulum, and 4) calsequestrin, the Ca(2+) storage protein in the sarcoplasmic reticulum. In addition, a multitude of Ca(2+)-binding proteins is present in muscle tissue including parvalbumin, calmodulin, S100 proteins, annexins, sorcin, myosin light chains, beta-actinin, calcineurin, and calpain. These Ca(2+)-binding proteins may either exert an important role in Ca(2+)-triggered muscle contraction under certain conditions or modulate other muscle activities such as protein metabolism, differentiation, and growth. Recently, several Ca(2+) signaling and handling molecules have been shown to be altered in muscle diseases. Functional alterations of Ca(2+) handling seem to be responsible for the pathophysiological conditions seen in dystrophinopathies, Brody's disease, and malignant hyperthermia. These also underline the importance of the affected molecules for correct muscle performance.

alpha and beta parvalbumins are Ca(2+)-binding proteins of the EF-hand type. We determined the protein sequence of human brain alpha parvalbumin by mass spectrometry and cloned human beta parvalbumin (or oncomodulin) from genomic DNA and preterm placental cDNA. beta parvalbumin differs in 54 positions from alpha parvalbumin and lacks the C-terminal amino acid 109. From MS analyses of alpha and beta parvalbumins we conclude that parvalbumins generally lack posttranslational modifications. alpha and beta parvalbumins were differently expressed in human tissues when analyzed by immunoblotting and polymerase-chain-reaction techniques. Whereas alpha parvalbumin was found in a number of adult human tissues, beta parvalbumin was restricted to preterm placenta. The pattern of alpha parvalbumin expression also differs in man compared to other vertebrates. For example, in rat, alpha parvalbumin was found in extrafusal and intrafusal skeletal-muscle fibres whereas, in man, alpha parvalbumin was restricted to the muscle spindles. Different functions for alpha and beta parvalbumins are discussed.