Raffaele De Caro

Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) Classification of Renal Tumours in Patients who are Candidates for Nephron-Sparing Surgery

BACKGROUND Besides clinical tumour size, other anatomical aspects of the renal tumour are routinely considered when evaluating the feasibility of elective nephron-sparing surgery (NSS). OBJECTIVE To propose an original, standardised classification of renal tumours suitable for NSS based on their anatomical features and size and to evaluate the ability of this classification to predict the risk of overall complications resulting from the surgery. DESIGN, SETTING, AND PARTICIPANTS We enrolled prospectively 164 consecutive patients who underwent NSS for renal tumours at a tertiary academic referral centre from January 2007 to December 2008. INTERVENTION Open partial nephrectomy without vessel clamping. MEASUREMENTS All tumours were classified by integrating size with the following anatomical features: anterior or posterior face, longitudinal, and rim tumour location; tumour relationships with renal sinus or urinary collecting system; and percentage of tumour deepening into the kidney. We generated an algorithm evaluating each anatomical parameter and tumour size (the preoperative aspects and dimensions used for an anatomical [PADUA] score) to predict the risk of complications. RESULTS AND LIMITATIONS Overall rates of complication were significantly correlated to all the evaluated anatomical aspects, excluding clinical size and anterior or posterior location of the tumour. By multivariate analysis, PADUA scores were independent predictors of the occurrence of any grade complications (hazard ratio [HR] for score 8-9 vs 6-7: 14.535; HR for score ≥10 vs 6-7: 30.641). Potential limitations were the limited number of patients with T1b tumours included in the study and the lack of laparoscopically treated patients. Further external validation of the PADUA score is needed. CONCLUSIONS The PADUA score is a simple anatomical system that can be used to predict the risk of surgical and medical perioperative complications in patients undergoing open NSS. The use of an appropriate score can help clinicians stratify patients suitable for NSS into subgroups with different complication risks and can help researchers evaluate the real comparability among patients undergoing NSS with different surgical approaches.

Toll-Like Receptor 2 Regulates Intestinal Inflammation by Controlling Integrity of the Enteric Nervous System

BACKGROUND & AIMS In the intestines, Toll-like receptor 2 (TLR2) mediates immune responses to pathogens and regulates epithelial barrier function; polymorphisms in TLR2 have been associated with inflammatory bowel disease phenotype. We assessed the effects of TLR2 signaling on the enteric nervous system (ENS) in mice. METHODS TLR2 distribution and function in the ileal neuromuscular layer of mice were determined by immunofluorescence, cytofluorimetric analysis, immunoprecipitation, and immunoblot analyses. We assessed morphology and function of the ENS in Tlr2(-/-) mice and in mice with wild-type Tlr2 (wild-type mice) depleted of intestinal microbiota, using immunofluorescence, immunoblot, and gastrointestinal motility assays. Levels and signaling of glial cell line-derived neurotrophic factor (GDNF) were determined using quantitative reverse transcriptase polymerase chain reaction, immunohistochemistry, and immunoprecipitation analyses. Colitis was induced by administration of dextran sulfate sodium or 2,4 dinitrobenzensulfonic acid to Tlr2(-/-) mice after termination of GDNF administration. RESULTS TLR2 was expressed in enteric neurons, glia, and smooth muscle cells of the intestinal wall. Tlr2(-/-) mice had alterations in ENS architecture and neurochemical profile, intestinal dysmotility, abnormal mucosal secretion, reduced levels of GDNF in smooth muscle cells, and impaired signaling via Ret-GFRα1. ENS structural and functional anomalies were completely corrected by administration of GDNF to Tlr2(-/-) mice. Wild-type mice depleted of intestinal microbiota had ENS defects and GDNF deficiency, similar to Tlr2(-/-) mice; these defects were partially restored by administration of a TLR2 agonist. Tlr2(-/-) mice developed more severe colitis than wild-type mice after administration of dextran sulfate sodium or 2,4 dinitrobenzensulfonic acid; colitis was not more severe if Tlr2(-/-) mice were given GDNF before dextran sulfate sodium or 2,4 dinitrobenzensulfonic acid. CONCLUSIONS In mice, TLR2 signaling regulates intestinal inflammation by controlling ENS structure and neurochemical coding, along with intestinal neuromuscular function. These findings provide information as to how defective TLR2 signaling in the ENS affects inflammatory bowel disease phenotype in humans.

Histological study of the deep fasciae of the limbs

The aim of this study is to analyse the deep fasciae of limbs in order to evaluate the collagen and elastic fibre arrangement and the types of innervation. Histological and immunohistochemical stains were performed in 72 specimens. The deep fascia of the limbs is a sheath presenting a mean thickness of 1mm, formed by two to three layers of parallel collagen fibre bundles. In the adjacent layers, they show different orientations. Each layer is separated from the adjacent one by loose connective tissue, permitting the sliding of the collagen layers. Nerve fibres were found in all specimens, while muscular fibres were evidenced only in one specimen. The described structure permits the fasciae of the limbs to have a strong resistance to traction, even when exercised in different directions. The capacity of the different collagen layers to glide one on the other could be altered in cases of overuse syndrome, trauma, or surgery.

Plantar fascia anatomy and its relationship with Achilles tendon and paratenon

Although the plantar fascia (PF) has been studied quite well from a biomechanical viewpoint, its microscopic properties have been overlooked: nothing is known about its content of elastic fibers, the features of the extracellular matrix or the extent of innervation. From a functional and clinical standpoint, the PF is often correlated with the triceps surae muscle, but the anatomical grounds for this link are not clear. The aim of this work was to focus on the PF macroscopic and microscopic properties and study how Achilles tendon diseases might affect it. Twelve feet from unembalmed human cadavers were dissected to isolate the PF. Specimens from each PF were tested with various histological and immunohistochemical stains. In a second stage, 52 magnetic resonance images (MRI) obtained from patients complaining of aspecific ankle or foot pain were analyzed, dividing the cases into two groups based on the presence or absence of signs of degeneration and/or inflammation of the Achilles tendon. The thickness of PF and paratenon was assessed in the two groups and statistical analyses were conducted. The PF is a tissue firmly joined to plantar muscles and skin. Analyzing its possible connections to the sural structures showed that this fascia is more closely connected to the paratenon of Achilles tendon than to the Achilles tendon, through the periosteum of the heel. The PF extended medially and laterally, continuing into the deep fasciae enveloping the abductor hallucis and abductor digiti minimi muscles, respectively. The PF was rich in hyaluronan, probably produced by fibroblastic‐like cells described as ‘fasciacytes’. Nerve endings and Pacini and Ruffini corpuscles were present, particularly in the medial and lateral portions, and on the surface of the muscles, suggesting a role for the PF in the proprioception of foot. In the radiological study, 27 of the 52 MRI showed signs of Achilles tendon inflammation and/or degeneration, and the PF was 3.43 ± 0.48 mm thick (99%CI and SD = 0.95), as opposed to 2.09 ± 0.24 mm (99%CI, SD = 0.47) in the patients in which the MRI revealed no Achilles tendon diseases; this difference in thickness of 1.29 ± 0.57 mm (99%CI) was statistically significant (P < 0.001). In the group of 27/52 patients with tendinopathies, the PF was more than 4.5 mm thick in 5, i.e. they exceeded the threshold for a diagnosis of plantar fasciitis. None of the other 25/52 paitents had a PF more than 4 mm thick. There was a statistically significant correlation between the thicknesses of the PF and the paratenon. These findings suggest that the plantar fascia has a role not only in supporting the longitudinal arch of the foot, but also in its proprioception and peripheral motor coordination. Its relationship with the paratenon of the Achilles tendon is consistent with the idea of triceps surae structures being involved in the PF pathology, so their rehabilitation can be considered appropriate. Finally, the high concentration of hyaluronan in the PF points to the feasibility of using hyaluronan injections in the fascia to treat plantar fasciitis.

Surgical anatomy of the pectoral nerves and the pectoral musculature

The pectoral nerves (PNs) may be selectively injured through various traumatic mechanisms such as direct trauma, hypertrophic muscle compression, and iatrogenic injuries (breast surgery and axillary node dissection, pectoralis major muscle transfers). The PN may be surgically recovered through nerve transfers. They may also be used as donors to the musculocutaneous, axillary, long thoracic, and spinal accessory nerves and for reinnervation of myocutaneous free flaps. Thus, in this article, we reviewed the surgical anatomy of PN. A meta‐analysis of the available literature showed that the lateral pectoral nerve (LPN) arises most frequently with two branches from the anterior divisions of the upper and middle trunks (33.8%) or as a single root from the lateral cord (23.4%). The medial pectoral nerve (MPN) usually arises from the medial cord (49.3%), anterior division of the lower trunk (43.8%), or lower trunk (4.7%). The two PN are usually connected immediately distal to the thoracoacromial artery by the so‐called ansa pectoralis. The MPN may also show communications with the intercostobrachial nerve. In 50%–100% of cases, it may pass, at least with some branches, through the pectoralis minor muscle. The LPN supplies the upper portions of the pectoralis major muscle; the MPN innervates the lower parts of the pectoralis major and the pectoralis minor muscle. Among the accessory muscles of the pectoral girdle, the LPN may also innervate the tensor semivaginae articulationis humero‐scapularis, pectoralis minimus, sternoclavicularis, axillary arch, sternalis, and infraclavicularis muscles; the MPN may innervate the pectoralis quartus, chondrofascialis, axillary arch, chondroepitrochlearis, and sternalis muscles. Clin. Anat. 25:559–575, 2012.

Histotopographic study of the fibroadipose connective cheek system.

The purpose of this study was to investigate the morphology of the superficial musculoaponeurotic system (SMAS). Eight embalmed cadavers were analyzed: one side of the face was macroscopically dissected; on the other side, full-thickness samples of the parotid, zygomatic, nasolabial fold and buccal regions were taken. In all specimens, a laminar connective tissue layer (SMAS) bounding two different fibroadipose connective layers was identified. The superficial fibroadipose layer presented vertically oriented fibrous septa, connecting the dermis with the superficial aspect of the SMAS. In the deep fibroadipose connective layer, the fibrous septa were obliquely oriented, connecting the deep aspect of the SMAS to the parotid-masseteric fascia. This basic arrangement shows progressive thinning of the SMAS from the preauricular district to the nasolabial fold (p < 0.05). In the parotid region, the mean thicknesses of the superficial and deep fibroadipose connective tissues were 1.63 and 0.8 mm, respectively, whereas in the region of the nasolabial fold the superficial layer is not recognizable and the mean thickness of the deep fibroadipose connective layer was 2.9 mm. The connective subcutaneous tissue of the face forms a three-dimensional network connecting the SMAS to the dermis and deep muscles. These connective laminae connect adipose lobules of various sizes within the superficial and deep fibroadipose tissues, creating a three-dimensional network which modulates transmission of muscle contractions to the skin. Changes in the quantitative and qualitative characteristics of the fibroadipose connective system, reducing its viscoelastic properties, may contribute to ptosis of facial soft tissues during aging.

Post-transcriptional silencing and functional characterization of the Drosophila melanogaster homolog of human Surf1.

Mutations in Surf1, a human gene involved in the assembly of cytochrome c oxidase (COX), cause Leigh syndrome, the most common infantile mitochondrial encephalopathy, characterized by a specific COX deficiency. We report the generation and characterization of functional knockdown (KD) lines for Surf1 in Drosophila. KD was produced by post-transcriptional silencing employing a transgene encoding a dsRNA fragment of the Drosophila homolog of human Surf1, activated by the UAS transcriptional activator. Two alternative drivers, Actin5C–GAL4 or elav–GAL4, were used to induce silencing ubiquitously or in the CNS, respectively. Actin5C–GAL4 KD produced 100% egg-to-adult lethality. Most individuals died as larvae, which were sluggish and small. The few larvae reaching the pupal stage died as early imagos. Electron microscopy of larval muscles showed severely altered mitochondria. elav–GAL4-driven KD individuals developed to adulthood, although cephalic sections revealed low COX-specific activity. Behavioral and electrophysiological abnormalities were detected, including reduced photoresponsiveness in KD larvae using either driver, reduced locomotor speed in Actin5C–GAL4 KD larvae, and impaired optomotor response as well as abnormal electroretinograms in elav–GAL4 KD flies. These results indicate important functions for SURF1 specifically related to COX activity and suggest a crucial role of mitochondrial energy pathways in organogenesis and CNS development and function.

Comparison of Transverse Carpal Ligament and Flexor Retinaculum Terminology for the Wrist

PURPOSE To investigate the macroscopic anatomy and histological characteristics of the transverse carpal ligament and the flexor retinaculum of the wrist and to investigate their anatomical relationships and define appropriate terminology. METHODS The volar regions of the wrists of 30 unembalmed subjects were examined by dissection and by histological and immunohistochemical staining. In vivo magnetic resonance imaging studies were also carried out on 10 subjects. RESULTS The dissection study showed that the antebrachial fascia at the volar aspect of the wrist presents a reinforcement. From a histological point of view, it is composed of 3 layers of undulated collagen fiber bundles. Adjacent layers show different orientations of the collagen fibers. Many nerve fibers and Pacini and Ruffini corpuscles were found in all specimens. Under this fibrous plane is another fibrous structure, placed transversely between the ulnar-sided hamate and pisiform bones, and the radial-sided scaphoid and trapezium bones. The deeper fibrous structure shows completely different histological characteristics, having parallel, thicker collagen fiber bundles and few nerve fibers. Magnetic resonance images confirm the presence of 2 clearly distinguished fibrous structures in the wrist, the first in continuity with the antebrachial fascia and the second located in a deeper plane between the hamate and scaphoid. CONCLUSIONS Two different fibrous structures with different histological characteristics are present in the volar wrist: the more superficial one is in continuity with the antebrachial fascia and could be considered its reinforcement; the deeper one is composed of strong lamina, with histological features similar to those of a ligament. For these reasons, we suggest that the term transverse carpal ligament should be used to indicate the fibrous lamina connecting the hamate and pisiform to the scaphoid and trapezium and that the term flexor retinaculum of the wrist should be abandoned because it does not correspond to any specific, autonomous structure.

Spexin expression in normal rat tissues.

Spexin is a highly conserved peptide which was recently identified through the bioinformatics approach. Immunohistochemical analysis of its expression has not yet been performed. Thus, in this study, we examined spexin location in a wide range of rat organs by both RT-PCR and IHC. RT-PCR identified spexin mRNA in all tissues examined. Spexin immunoreaction was mainly cytoplasmic. Spexin was immunohistochemically detected, although with different staining intensities, in epithelia and glands of skin and respiratory, digestive, urinary, and reproductive systems. Smooth muscle cells showed weak immunostaining, and connective tissue was negative. In the central nervous system, neuronal groups showed different intensities for reaction product. Immunoreaction was also found in ganglionic cells of both trigeminal and superior cervical ganglia and in photoreceptor, inner nuclear, and ganglionic layers of the retina. In the endocrine system, spexin immunoreaction was detected in the hypothalamic paraventricular and supraoptic nuclei; adenohypophysis, thyroid, and parathyroid glands; adrenal cortex and medulla (mainly ganglionic cells); Leydig cells; and thecal, luteal, and interstitial cells of the ovary. Because of its widespread expression, spexin is probably involved in many different physiological functions; in particular, location of spexin in neurons and endocrine cells suggests its roles as neurotransmitter/neuromodulator and endocrine factor.

The Ankle Retinacula: Morphological Evidence of the Proprioceptive Role of the Fascial System

Study Design: Research report. Objectives: To evaluate the anatomical characteristics of the ankle retinacula and their relationship with the fasciae and muscles in healthy subjects and in patients with ankle sprain outcomes. Background: The role of the retinacula in proprioception has begun to emerge, but without clear anatomical bases or descriptions of their possible damage in patients with ankle sprain outcomes. Methods: Dissection, histological and immunohistochemical analysis of 27 legs. An in vivo radiological study by MRI was also performed on 7 healthy volunteers, 17 patients with outcomes of ankle sprain, and 3 amputated legs. Results: The retinacula are thickenings of the deep fascia presenting bone or muscular connections. They are formed of 2–3 layers of parallel collagen fibre bundles, densely packaged with a little loose connective tissue, without elastic fibres but many nervous fibres and corpuscles. By MRI, the retinacula appeared as low-signal-intensity bands with a mean thickness of 1 mm. In patients with outcomes of ankle sprain, MR findings were abnormal retinacula thickness, signal intensity, and full-thickness gap. Discussion: The retinacula are not static structures for joint stabilisation, like the ligaments, but a specialisation of the fascia for local spatial proprioception of the movements of foot and ankle. Their anatomical variations and accessory bundles may be viewed as morphological evidence of the integrative role of the fascial system in peripheral control of articular motility.