Multiscale X-ray phase-contrast tomography: From breast CT to micro-CT for virtual histology.

Phase-contrast imaging techniques address the issue of poor soft-tissue contrast encountered in traditional X-ray imaging. This can be accomplished with the propagation-based phase-contrast technique by employing a coherent photon beam, which is available at synchrotron facilities, as well as long sample-to-detector distances. This study demonstrates the optimization of propagation-based phase-contrast computed tomography (CT) techniques for multiscale X-ray imaging of the breast at the Elettra synchrotron facility (Trieste, Italy). Two whole breast mastectomy samples were acquired with propagation-based breast-CT using a monochromatic synchrotron beam at a pixel size of 60 µm. Paraffin-embedded blocks sampled from the same tissues were scanned with propagation-based micro-CT imaging using a polychromatic synchrotron beam at a pixel size of 4 µm. Images of both methodologies and of the same sample were spatially registered. The resulting images showed the transition from whole breast imaging with propagation-based breast-CT methodology to virtual histology with propagation-based micro-CT imaging of the same sample. Additionally, conventional histological images were matched to virtual histology images. Phase-contrast images offer a high resolution with low noise, which allows for a highly precise match between virtual and conventional histology. Furthermore, those techniques allow a clear discernment of breast structures, lesions, and microcalcifications, being a promising clinically-compatible tool for breast imaging in a multiscale approach, to either assist in the detection of cancer in full volume breast samples or to complement structure identification in paraffin-embedded breast tissue samples.

Growth hormone deficiency and other endocrinopathies after childhood brain tumors: results from a close follow-up in a cohort of 242 patients.

PURPOSE: Brain tumors are the most common solid tumor in children. The prevalence of survivors from these cancers has been increasing, presenting endocrine sequelae in more than 40% of the cases. Our aim was to characterize the endocrinopathies diagnosed in this population, exploring the outcomes of growth hormone treatment. METHODS: We have performed a retrospective analysis of the survivors that were followed-up through a close protocol at our endocrine late-effects clinic. RESULTS: 242 survivors, followed during 6.4 (0-23.4) years, were considered. The median age at tumor diagnosis was 6.7 (0-18) years and pilocytic astrocytoma was the most frequent neoplasm (33.5%). The prevalence of endocrinopathies was of 71.5%, with growth hormone deficiency being the most frequent (52.9%). An indirect correlation between the age at the beginning of somatropin and growth velocity in the first year of treatment was observed. Those treated with craniospinal radiotherapy presented a smaller final upper/lower segments ratio comparing with those that only received cranial radiotherapy. However, their final height was not compromised when compared to their family height target. We found pubertal delay in 12%; accelerated/precocious puberty in 13.2%; central and primary hypogonadism in 21.9% and 3.3%, respectively; primary and central hypothyroidism in 23.6% and 14.5%, respectively; thyroid nodules in 7.4%; ACTH deficiency in 10.3% and diabetes insipidus in 12%. CONCLUSION: This study reveals a higher prevalence of endocrinopathies in brain tumors survivors and explores the influence of craniospinal irradiation in the adult body proportions. It reinforces the importance of routine follow-up among survivors.

All-inside repair of meniscal bucket handle tears: a retrospective study at mean 4-years follow-up evaluation.

Bucket-handle tears represent approximately 10% of all meniscal tears. Despite the common treatment is subtotal meniscectomy, repair is technically feasible although complex, and represents a key strategy to avoid severe meniscal tissue loss that could accelerate joint degeneration over time. The aim of this retrospective study was to determine the outcomes of arthroscopically-assisted bucket-handle tear repair, and to identify factors correlating with clinical results. Fifty-four patients affected by meniscal bucket handle tear were included in the present retrospective analysis and evaluated up to mean 4-years follow-up. All patients were treated by arthroscopic-assisted all-inside repair. The primary outcome was considered the need for a re-operation due to failure of meniscal repair. Patients were also evaluated by the following items: KOOS, Lysholm, Tegner, IKDC-subjective and Quadruple-VAS score. Subgroup analysis was performed to identify whether concurrent ACL reconstruction, side of the lesion, age at surgery and time from injury to repair could influence clinical outcome. Ten out 54 patients (18.5%) were considered failed and needed reoperation, mainly within one year from surgery. Overall, there was a significant increase in all clinical scores considered and patients were able to get back to previous sport activity level. Patients with concurrent ACL reconstruction presented a lower risk of failure (p=0.025). Patients with lateral meniscus repair showed better clinical outcome compared to medial meniscus. Timing from injury and age at surgery did not correlated with clinical outcome. Our series showed fair results in bucket handle repair up to middle term evaluation. Concomitant ACL reconstruction was associated with lower failure rate whereas lateral meniscus involvement was associated with higher functional scores at final follow-up evaluation.

Incidental finding of adenocarcinoma in a gallbladder lumen with no wall involvement.

Gallbladder cancer (GBC) is a rare disease characterized by its aggressiveness. Resection with free tumour margins is the sole curative treatment and, in incidental findings, surgical reapproach is recommended for segmentectomy IVb and V or wedge resection of the gallbladder fossa and lymphadenectomy. Here we report a case of gallbladder adenocarcinoma as an incidental finding in a fragment in its lumen with no wall involvement evidentiated. The patient was reoperated for resection of the gallbladder bed with hepatic hilum and cystic duct lymphadenectomy, later evidentiated as free of residual disease. The normality of the bile ducts evidenced by imaging studies, in addition to signs of chronic cholecystitis corroborate to GBC diagnosis. We suspect that the fragment was detached gallbladder polypoid neoplastic lesion. Despite the lack of clinical manifestations, the fast surgical interventions and the histopathological analysis of the material was probably a prognostic determinant for the patient.

Autologous micro-fragmented adipose tissue for the treatment of diffuse degenerative knee osteoarthritis: an update at 3 year follow-up.

BACKGROUND: Conservative therapies for the treatment of knee degenerative processes are used before resorting to surgery; nonetheless, they may offer only short-term benefits. Encouraging preliminary results have been reported using mesenchymal stem cells (MSCs), either alone or in association with surgery. Among the many sources, adipose tissue has created a huge interest, because of its anti-inflammatory and regenerative properties ascribed to the cells of its stromal vascular fraction. We previously reported the safety and feasibility of autologous micro-fragmented adipose tissue as adjuvant for the surgical treatment of diffuse degenerative chondral lesions at 1 year. Here we present the outcomes of the same cohort of patients evaluated at 3 year follow-up. Micro-fragmented adipose tissue was obtained using a minimal manipulation technique in a closed system. The safety of the procedure was evaluated by recording type and incidence of any adverse event. The clinical outcomes were determined using the KOOS, IKDC-subjective, Tegner Lysholm Knee, and VAS pain scales taken pre-operatively and at 12 and 36 months follow-up. FINDINGS: No adverse events, lipodystrophy cases at the harvesting site nor atypical inflammatory reactions at the joint level were reported. Of the 30 patients previously treated, one was lost, and seven received additional treatments in the period of observation. On average, the 22 patients that had no other treatments in the 3-year period showed that the results observed at 1 year were maintained. Moreover, 41, 55, 55 and 64% of the patients improved with respect to the 1-year follow-up in the Tegner Lysholm Knee, VAS, IKDC-subjective and total KOOS, respectively. CONCLUSION: Our results point to autologous and micro-fragmented adipose tissue injection as an innovative and safe approach for the management of diffuse degenerative knee chondropathy in the mid-term. The procedure is simple, affordable, minimally invasive, and compliant with the regulatory panorama.

Prognostic and predictive role of neutrophil/lymphocytes ratio in metastatic colorectal cancer: a retrospective analysis of the TRIBE study by GONO.

Background: Neutrophil/lymphocyte ratio (NLR), defined as absolute neutrophils count divided by absolute lymphocytes count, has been reported as poor prognostic factor in several neoplastic diseases but only a few data are available about unresectable metastatic colorectal cancer (mCRC) patients (pts). The aim of our study was to evaluate the prognostic and predictive role of NLR in the TRIBE trial. Patients and methods: Pts enrolled in TRIBE trial were included. TRIBE is a multicentre phase III trial randomizing unresectable and previously untreated mCRC pts to receive FOLFOXIRI or FOLFIRI plus bevacizumab. A cut-off value of 3 was adopted to discriminate pts with low (NLR < 3) versus high (NLR ≥ 3) NLR, as primary analysis. As secondary analysis, NLR was treated as an ordinal variable with three levels based on terciles distribution. Results: NLR at baseline was available for 413 patients. After multiple imputation at univariate analysis, patients with high NLR had significantly shorter progression-free survival (PFS) [hazard ratio (HR) 1.27 (95% CI 1.05-1.55), P = 0.017] and overall survival (OS) [HR 1.56 (95% CI 1.25-1.95), P < 0.001] than patients with low NLR. In the multivariable model, NLR retained a significant association with OS [HR 1.44 (95% CI 1.14-1.82), P = 0.014] but not with PFS [HR 1.18 (95% CI 0.95-1.46), P = 0.375]. No interaction effect between treatment arm and NLR was evident in terms of PFS (P for interaction = 0.536) or OS (P for interaction = 0.831). Patients with low [HR 0.84 (95% CI 0.64-1.08)] and high [HR 0.73 (95% CI 0.54-0.97)] NLR achieved similar PFS benefit from the triplet and consistent results were obtained in terms of OS [HR 0.83 (95% CI 0.62-1.12) for low NLR; HR 0.82 (95% CI 0.59-1.12) for high NLR]. Conclusion: This study confirmed the prognostic role of NLR in mCRC pts treated with bevacizumab plus chemotherapy in the first line, showing the worse prognosis of pts with high NLR. The advantage of the triplet is independent of NLR at baseline.

Knee Septic Arthritis after Arthroscopy: Incidence, Risk Factors, Functional Outcome, and Infection Eradication Rate.

Purpose Septic knee arthritis following arthroscopy is a rare but dreaded complication. Definition and management of knee deep infections are quite discussed in literature. In this review, literature regarding infections after knee arthroscopy is analyzed highlighting the incidence, causative bacteria, risk factors as well as clinical outcomes. Methods We performed a review of the literature matching the following key words: "septic arthritis" OR "infection" AND "arthroscopy" AND "knee." Knee arthroscopic procedures, such as debridement, meniscectomy, meniscus repair, synovectomy, microfracture, and lateral release, were considered. Complex procedures, such as ligament reconstruction, fractures, or complex cartilage repair techniques, were not included. Results Thirteen studies were included in this review. Incidence of infection ranged from 0.009 to 1.1% in patients undergoing simple arthroscopic procedures. Staphylococci are the most commonly isolated organisms from postarthroscopy infection. Use of intraoperative intra-articular steroids, smoking, obesity, male sex, diabetes, number of procedures performed during surgery, time of surgery, and tourniquet time of more than 60 minutes have been certified as risk factors for knee infection. Conclusion Postarthroscopy septic arthritis of the knee causes significant morbidity, usually requiring readmission to the hospital, at least one additional operation, and prolonged antibiotic therapy, both intravenous and oral. Prompt diagnosis and treatment are associated with a high success rate. Level of Evidence Level IV, systematic review of I-IV studies.

Heat shock induces the expression of pro-inflammatory cytokines in human Achilles tendon tenocytes.

The aim of our study is to investigate the behaviour of healthy and tendinopathic human tenocytes after a heat shock. After we harvested tendinopathic and healthy human tendon samples, we split tenocytes into 4 groups: 3 groups were submitted to heat shock, followed by different periods of post-heating (2, 4 and 20 h). The other group represents our negative control. The target genes were analysed using Real Time PCR. IL-1ß and IL-6 expression were significantly increased in tendinopathic samples after heat shock. COL1 and COL3 expression were increased in non-stimulated tendinopathic tenocytes, but their levels significantly decreased after heat shock (p less than 0.01). COL3 levels increase in healthy samples after 20 h post-heating (p less than 0.01). COL1 and COL3 decreased after heat shock as a sign of the failure of repair mechanisms in tendinopathic tendons. Heat shock in in vitro models was insufficient to trigger pro-inflammatory cytokines in healthy human tenocytes.

Surgical treatment of sacral chordoma: survival and prognostic factors.

INTRODUCTION: Sacral chordoma is a rare low-to-intermediate grade malignant tumour. The mainstay of treatment is still surgery with en bloc and wide resection margins, which can grant the best chances of a long-term control or cure of this disease. The first aim of this paper is to collect data about survival, time to local recurrence and metastasis among patients affected by sacral chordoma and primarily treated with surgery. The second aim is to analyze the influence of level resection, tumor volume and surgical margins on local recurrence. MATERIALS AND METHODS: The study population was composed of 14 patients treated with sacral chordoma resection at the National Tumour Institute of Naples-Pascale (Italy) from January 2000 to June 2013. The median follow-up was 84 months (range 24-132 months). The follow-up was characterized by: standard radiographs, MRI, and a CT scan of the chest annually. Time to recurrence or metastasis was calculated from the date of resection to the date of diagnosis of first recurrence or metastasis. RESULTS: Out of all the patients, six died (42.86 %) during the follow-up; 6 (42.86 %) had local recurrence; 4 (28.57 %) had metastasis. At univariate analysis wide surgical margins (R0) were associated with increased survival up to a local recurrence (OR = 0.0286; 95 % CI = 0.0014-0.5739; P = 0.026); the level of resection (OR = 3.33; 95 % CI = 0.3619-30.7025; P = 0.592) and tumour volume (P = 1) did not show a statistically significant correlation. DISCUSSION: Based on our experience, we hope all patients to be treated by surgery, the only good standard treatment of this disease. The resection should result in margins as wide as possible. For these reasons, it is essential for this disease to be treated in highly specialized centres because only a complete surgery can offer a chance to care for these patients. CONCLUSIONS: Solid survival at long-term follow-up can be achieved by a surgical resection performed with wide margins.

Early tumor shrinkage and depth of response predict long-term outcome in metastatic colorectal cancer patients treated with first-line chemotherapy plus bevacizumab: results from phase III TRIBE trial by the Gruppo Oncologico del Nord Ovest.

BACKGROUND: Early tumor shrinkage (ETS) and depth of response (DoR) predict overall survival (OS) in first-line trials of chemotherapy ± anti-EGFR monoclonal antibodies in metastatic colorectal cancer (mCRC). These associations and the predictive accuracy of response measurements for survival parameters were investigated in the phase III TRIBE trial of FOLFOXIRI plus bevacizumab (bev) versus FOLFIRI plus bev. PATIENTS AND METHODS: A landmark approach was adopted to define the assessable population. The distribution of RECIST response rate, ETS and DoR was compared in the two arms. Associations between response measurements and progression-free survival (PFS), post-progression survival (PPS) and OS were tested by univariate and multivariate Cox models. Prediction performance of each factor was estimated by C-index. RESULTS: A significantly higher percentage of patients in the FOLFOXIRI plus bev arm achieved ETS ≥20%, when compared with the control arm (62.7% versus 51.9%, P = 0.025). Also the DoR was significantly higher in the triplet plus bev arm (43.4% versus 37.8%, P = 0.003). Both ETS and DoR were associated with PFS, PPS and OS at the univariate analyses and in the multivariate models stratified for other prognostic variables. Both ETS and DoR were able to predict survival as accurately as RECIST response. CONCLUSION: FOLFOXIRI plus bev improves ETS and DoR when compared with FOLFIRI plus bev. Achieving rapid and deep tumor shrinkage consistently delays tumor progression and prolongs survival in patients treated with first-line chemotherapy plus bev. ETS is a promising and valuable end point for clinical trials' design deserving further investigation.

Factors associated with the need for blood transfusion during hysterectomy.

OBJECTIVE: To identify the preoperative clinical conditions associated with the need to perform a blood transfusion among patients undergoing hysterectomy. METHODS: In a retrospective, comparative, case-control trial at the University Hospital, Nuevo León, Mexico, the records of patients who underwent elective hysterectomy between 2007 and 2009 were reviewed. Patients were grouped depending on whether or not they required blood transfusion. Clinical features were compared and statistical analysis was performed via the χ(2) test. RESULTS: Among 794 patients who underwent hysterectomy, 89 (11.2%) required transfusion. The factors significantly associated with transfusion were history of abnormal uterine bleeding (67.0% versus 52.1%), preoperative hemoglobin level (10.1g/dL versus 12.3g/dL), magnitude of intra-operative bleeding (410 mL versus 298 mL), and operative time (172 min versus 144 min); P<0.001. A significant number of patients who underwent transfusion had increased preoperative prothrombin levels; P=0.04. CONCLUSION: Hemoglobin level before surgery and a history of abnormal uterine bleeding can be identified preoperatively and might warn about the possibility of a need for transfusion among patients undergoing hysterectomy. For young patients, alterations in clotting mechanisms should be ruled out.

Oxidative stress, inflammation, and muscle soreness in an 894-km relay trail run.

We describe the effects of multi-day relay trail running on muscle soreness and damage, and systemic immune, inflammatory, and oxidative responses. 16 male and 4 female athletes ran 894 km in 47 stages over 95 h, with mean (SD) 6.4 (1.0) stages per athlete and 19.0 (1.7) km per stage. We observed post-pre run increases in serum creatine kinase (qualified effect size extremely large, p = 0.002), IL-6 (extremely large, p < 0.001), urinary 8-isoprostane/creatinine (extremely large, p = 0.04), TNF-α (large, p = 0.002), leukocyte count (very large, p < 0.0001) and neutrophil fraction (very large, p < 0.001); and reductions in hemoglobin (moderate, p < 0.001), hematocrit (moderate, p < 0.001), and lymphocyte fraction (trivial, p < 0.001). An increase in ORAC total antioxidant capacity (TAC, small, p = 0.3) and decrease in urinary 8-OHdG/creatinine (small, p = 0.1) were not statistically significant. During the run, muscle soreness was most frequent in the quadriceps. The threshold for muscle pain (pain-pressure algometry) in the vastus lateralis and gastrocnemius was lower post-run (small, p = 0.04 and 0.03). Average running speed was correlated with algometer pain and leukocyte count (large, r = 0.52), and TAC was correlated with IL-6 (very large, r = 0.76) and 8-isoprostane/creatinine (very large, r = -0.72). Multi-day stage-racing increases inflammation, lipid peroxidation, muscle damage and soreness without oxidative DNA damage. High TAC is associated with reduced exercise-induced lipid peroxidation, but is not related to immune response or muscle damage.

Pulmonary congenital cystic disease in adults. Spiral computed tomography findings with pathologic correlation and management.

PURPOSE: The aim of this study was to assess the computed tomography (CT) features of intrapulmonary congenital cystic diseases in adults and to correlate the imaging features with the pathological findings, with emphasis on the oncogenic potential of the lesions. MATERIALS AND METHODS: We retrospectively reviewed the CT scans in three institutions from August 1996 to December 2008, of nine patients (six men, three women; mean age 48.6 years; range 26-75 years) who had histological diagnosis of pulmonary cystic disease after surgery. Six patients had a diagnosis of intrapulmonary bronchogenic cyst (IBC), and three had a type-I cystic adenomatoid malformation (CAM). In one case, intralobar sequestration (ILS) was associated with type-I CAM. RESULTS: Three patients were symptomatic and six were asymptomatic. On CT scans, IBCs showed homogeneous fluid attenuation (n=2), air-fluid level (n=2), air attenuation (n=1) or soft-tissue attenuation (n=1). The surrounding lung tissue showed areas of band-like linear attenuation in three IBCs, atelectasia in two and mucocele-like areas in one. On CT, type-I CAM appeared as a unilocular cystic lesion with air-fluid level (n=1) or air content (n=1). Both cases had thin walls surrounded by normal lung parenchyma. ILS appeared as a fluid-filled cyst with afferent and efferent vessels. Of the six IBCs, one occurred in the upper right lobe, two in the middle lobe and three in the lower right lobe. Of the three type-I CAMs, one was in the upper left lobe and one in the middle lobe. The type-I CAM associated with ILS was located in the left lower lobe. CONCLUSIONS: The similar CT patterns preclude differentiation between IBC and type-I CAM. Surgical resection of all intrapulmonary cystic lesions detected in adults is mandatory because type-I CAM is a precursor of mucinous bronchioloalveolar carcinoma.

A multicenter phase II study of the combination of oxaliplatin, irinotecan and capecitabine in the first-line treatment of metastatic colorectal cancer.

The triple drug combination consisting of irinotecan, oxaliplatin and 5-fluorouracil (FOLFOXIRI) has demonstrated higher activity and efficacy compared to the doublet FOLFIRI. 5-Fluorouracil could be substituted in FOLFOXIRI regimen by capecitabine, an oral fluoropyrimidine with similar efficacy. Recently, a dose-finding trial has demonstrated the feasibility of the combination of irinotecan, oxaliplatin and capecitabine (XELOXIRI) and established their recommended doses. The aim of this study was to evaluate the activity of XELOXIRI. A total of 36 patients with unresectable metastatic colorectal cancer received irinotecan 165 mg m(-2) and oxaliplatin 85 mg m(-2) on day 1 plus capecitabine 2000 mg m(-2) per day orally in two doses from day 1 to day 7, every 2 weeks. Grade 3-4 toxicities were infrequent, expect for neutropenia and diarrhoea, which were each observed in 30% of patients. Two complete and twenty-two partial responses were obtained, corresponding to an overall response rate of 67% (95% CI 51.4-82%). After a median follow-up of 17.7 months, the median progression-free and overall survival were 10.1 and 17.9 months, respectively. The substitution of 5-fluorouracil with capecitabine, in combination with irinotecan and oxaliplatin, is feasible and does not impair the activity of the regimen. However, the XELOXIRI combination is associated with a high incidence of diarrhoea and, therefore, should be considered as a not preferable alternative to FOLFOXIRI.

Initial experience with breast biopsy utilizing the Advanced Breast Biopsy Instrumentation (ABBI).

The Advanced Breast Biopsy Instrumentation (ABBI) system combines a cylindrical single-use biopsy device with digital stereotactic imaging that achieves targeting of radiographic lesions to +/- 1 mm. This minimally invasive technique uses digital stereotactic imaging to perform excisional biopsies of suspicious, nonpalpable mammographic lesion. This allows complete removal of specimens in a one-step procedure that does not involve separate trips to radiology and then surgery. The authors' initial 170 cases utilizing the ABBI system were reviewed. The accuracy of specimen targeting, the success rate of lesion removal, and operative complications were some of the issues assessed. Five cases were not suitable for the procedure: the mammographic lesion was not visualized in one, and the breast was too thin on compression in four. There was successful removal of the lesion in 165 of the remaining cases. There were no local wound complications, and patient satisfaction was high in all completed biopsies. The ABBI system is an effective new form of minimally invasive breast surgery. It provides complete excision of mammographic abnormalities.

The hemodynamic and metabolic effects of tourniquet application during knee surgery.

UNLABELLED: We evaluated the effects of tourniquet application on the cardiovascular system and metabolism in 10 young men undergoing knee surgery with general anesthesia. The duration of inflation was from 75 to 108 min. Heart rate, mean arterial pressure, cardiac index (CI) by pulse contour method, and systemic vascular resistance were measured before, during, and after tourniquet inflation. pH, PaO(2), PaCO(2), and lactate blood concentrations were also measured. VO(2) and VCO(2) were assessed every minute from tracheal intubation up to 15 min after tourniquet deflation and VO(2) in excess of the basal value over the 15 min after deflation (VO(2)exc) was calculated. Mean arterial pressure increased 26% (P: < 0.05) during inflation and returned to basal values after deflation. CI did not change immediately after inflation; although, thereafter, it increased 18% (P: < 0.05). Five minutes after deflation, CI further increased to a value 40% higher than the basal value. Therefore, systemic vascular resistance increased 20% suddenly after inflation (P: < 0.05) and decreased 18% after deflation (P: < 0.05). VO(2) and VCO(2) remained stable during inflation and increased (P: < 0.05) after deflation. VO(2)exc depended on duration of tourniquet inflation time (Tisch) (P: < 0.05). After deflation, PaCO(2) and lactate increased (P: < 0.05) while Tisch increased. We conclude that tourniquet application induces modifications of the cardiovascular system and metabolism, which depend on tourniquet phase and on Tisch. Whether these modifications could be relevant in patients with poor physical conditions is not known. IMPLICATIONS: The clinical effects of tourniquet application were evaluated in 10 young men undergoing knee surgery. Our data indicate that tourniquet application causes hemodynamic and metabolic changes which may become clinically relevant after a long period of tourniquet inflation, particularly in patients with concomitant cardiovascular diseases.

Phenotypic manifestations associated with CAG-repeat expansion in the androgen receptor gene in male patients and heterozygous females: a clinical and molecular study of 30 families.

Spinal and bulbar muscular atrophy (Kennedy disease) is an adult form of X-linked motor neuron disease caused by the expansion of a polymorphic CAG-repeat sequence in the first exon of the androgen receptor gene. We studied clinical and molecular features of 36 patients and 19 heterozygous females. Phenotypic manifestations and disease severity broadly varied among our spinal and bulbar muscular atrophy patients. The size of CAG expansion significantly influences the age of disease onset, but neither clinical features nor disease severity. The majority of carrier women presented signs of chronic denervation at neurophysiological examination and, in three cases, low-amplitude sensory action potentials were recorded. Notably, a few women developed mild signs of bulbar motor neuron impairment later in life. The identification of a large number of patients by the use of the molecular test further supports the hypothesis that Kennedy disease had been previously underdiagnosed, probably because of the great variability of clinical presentation. Although an early diagnosis may not be crucial for treatment, given the lack of effective therapy, the molecular testing can be of great relevance for disease prognosis and genetic counseling.

Disorders related to mitochondrial membranes: pathology of the respiratory chain and neurodegeneration.

Faulty oxidative phosphorylation (OXPHOS) is observed in a number of mitochondrial disorders, and may be associated with single or multiple defects of the five complexes of the respiratory chain. From the genetic standpoint, the respiratory chain is unique as it is formed by means of the complementation of two separate genetic systems: the nuclear genome and the mitochondrial genome. The nuclear genome encodes most of the protein subunits of the respiratory complexes and most of the mtDNA replication and expression systems, whereas the mitochondrial genome encodes only 13 OXPHOS subunits and some RNA components of the mitochondrial translation apparatus. Accordingly, mitochondrial disorders due to defects in oxidative phosphorylation include both Mendelian-inherited and cytoplasmic-inherited diseases. Although our knowledge of these diseases has grown at an impressive rate in the past few years, it is worth noting that, as a result of complementation in the respiratory chain of nuclear-encoded and mitochondrially-encoded polypeptides, it is often difficult to establish a precise relationship between genomic mutations and biochemical phenotypes, or to distinguish pathogenic mutations from polymorphic variants in gene sequences. This review deals with human diseases due to mutations of the structural components of the respiratory chain, particularly focusing on the recently identified disorders caused either by mutations in nuclear genes encoding subunits of the subcomplexes or by mutations in nuclear genes affecting the functional efficiency, homeostasis, and assembly of respiratory chain subcomplexes. To better focus on OXPHOS genotype-phenotype correlations, mutations of the mtDNA-encoded structural genes are also discussed.