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The latest development in the anterior lumbar interbody fusion (ALIF) procedure is its application in the lateral position to allow for simultaneous posterior percutaneous screw placement. The technical details of the lateral ALIF technique have not yet been described. To describe the surgical anatomy relevant to the lateral ALIF approach we performed a comprehensive anatomical study. In addition, the preoperative imaging, patient positioning, planning of the skin incision, positioning of the C-arm, surgical approach, and surgical technique are discussed in detail. The technique described led to the successful use of the lateral ALIF technique in our clinical cases. No lateral ALIF procedure needed to be aborted during these cases. Our present work gives detailed anatomical background and technical details for the lateral ALIF approach. This teaching article can provide readers with sufficient technical and anatomical knowledge to assist them in performing their first lateral ALIF procedure., (© 2021 American Association of Clinical Anatomists.)

Objective: The posterolateral extradural suboccipital approach can be used to reach the anterior epidural space and the retro-odontoid regions. The extent of necessary bone removal of the atlas vertebra (C1) has not yet been defined. We studied the changes in the size of the horizontal and vertical surgical windows using stepwise bone removal of C1. A representative case is shown., Methods: The anatomical study was performed bilaterally on five Thiel-fixed human cadavers (mean age, 83.7 years). The surgical window (horizontal × vertical) required to access the retro-odontoid region via a posterolateral approach was measured for an intact C1 posterior arch, after a semicircular inferior partial resection of the C1 arch, after resection of the unilateral hemiarch of C1, and finally after drilling approximately 3 mm from the medial aspect of the lateral mass of C1., Results: The intact C1 resulted in a very narrow surgical window of 6.3 mm × 9.7 mm (horizontal × vertical). The vertical window increased to a 13 mm after the semicircular inferior partial resection of the C1 arch and to 17.3 mm in the case of removal of the ipsilateral C1 posterior arch. The bone removal from the medial aspect of the C1 lateral mass resulted in a widening of the horizontal surgical window to 10.3 mm. The final size of the surgical window was 10.3 mm × 17.3 mm. The patient with severe kyphoscoliosis of the craniocervical spine was successfully operated on using odontoid and C1-2 facet osteotomies., Conclusion: If only the anterior epidural space or the base of the odontoid needs to be reached, the semicircular inferior partial resection of the C1 arch allows for an adequate surgical window. The tip of the odontoid could only be reached if the ipsilateral posterior arch is resected.

Purpose: We examined the accessory atlantoaxial ligaments and found them to be a part of a complex ligamentous structure, which we named craniocervical Y-ligament with respect to its shape., Methods: The ligaments of the upper cervical spine were dissected in ten Thiel embalmed human cadavers. Origin and attachment of the Y-ligament were described and a detailed photo and video-documentation was carried out with the head in the neutral position, flexion, extension and rotation to study the ligament during these movements., Results: The Y-ligaments were found to be paired and symmetric in all specimens. The shape of the ligament is similar to an Y, its lateral arm connecting the atlas to the axis, its medial arm connecting the occipital bone to the axis, fusing with the two main ligaments, the alar and transverse ligaments. The lateral arm of the Y-ligament was found to be analogous to the accessory atlantoaxial ligament. During cervical flexion, both arms of the Y-ligament became taut while extension made the Y-ligaments relaxed. During rotation both Y-ligaments became taut, moving in the opposite directions in the sagittal plane while following the gliding movements of the lateral masses of the atlas., Conclusions: The craniocervical Y-ligament is a complex ligamentous structure and has a constant anatomy. Because of its shape and special arrangement, it probably plays a role in limiting both atlantooccipital and atlantoaxial movements. Acknowledgement of this ligamentous structure will help understand upper cervical stability. The present study should serve as a basis for future biomechanical and radiological studies.

Mass spectrometry is a high sensitivity, highly selective, high throughput analytical technique. It is well suited to characterize polar, high mass molecules. It is one of the prime analytical techniques to study proteins, to determine their molecular mass, their amino acid sequence and their post-translational modifications. The objective of the present article is to introduce the most important mass spectrometry based methods relevant for protein analysis, like ionization techniques, mass analyzers and tandem mass spectrometry. We shall also introduce ,,top-down" and ,,buttom-up" protein sequencing and protein quantitation as well.

The therapeutic use of opioids is limited by the development of tolerance to the analgesic effect and the cellular and molecular mechanisms underlying this phenomenon are still not completely understood. For this reason the search for new analgesic derivatives, endowed with lower tolerance, is always an active field. The newly synthesized 14-O-Methylmorphine-6-sulfate (14-O-MeM6SU) shows high efficacy in in vitro assays and a strong analgesic action in the rat tail flick test. The aim of present work was to investigate: the analgesic effect of 14-O-MeM6SU in mouse tail-flick test; the tolerance to analgesic effect of 14-O-MeM6SU compared to morphine in mice, the effects of test compounds on glutamatergic neurotransmission by measuring spontaneous excitatory postsynaptic currents (sEPSCs) of layer V pyramidal cells from rat prefrontal cortices; and the effect of acute and chronic 14-O-MeM6SU treatments on opioid receptor gene expression in SH-SY5Y neuroblastoma cells expressing μ-opioid (MOP) and nociceptin/opioid receptor-like 1 (NOP) receptors. 14-O-MeM6SU was 17 times more potent than morphine in analgesia and had long duration of action in analgesic dose equipotent to morphine. Mice were treated subcutaneously (s.c.) either with 200 μmol/kg morphine or with 14-O-MeM6SU (12 μmol/kg) twice daily for three days. The magnitude of tolerance or cross-tolerance indicated by the shift in antinociceptive ED50 measured was greater for morphine compared to 14-O-MeM6SU. Subsequent to behavioral testing, patch-clamp experiments in layer V pyramidal neurons of rat prefrontal cortical slices in the presence of bicuculline were performed. Both 14-O-MeM6SU (0.1 μM) and morphine (1 μM) decreased the frequency of sEPSCs, indicating reduction of glutamate release. The effect of the novel compound was reversed by the opioid receptor antagonist naloxone, indicating an opioid mediated action. In contrast, the amplitude was not affected. Finally, gene expression data showed a dose dependent down-regulation of MOP receptor after 24h and 48 h exposure to 14-O-MeM6SU. Interestingly, no changes were detected for NOP receptor gene expression. The specific lack of this effect could be related to the lower tolerance development to analgesic effect of 14-O-MeM6SU. Furthermore, 14-O-MeM6SU displayed high intrinsic efficacy possibly an important factor in the observed effects. Further, the observed inhibition of glutamatergic signaling might be attributed also to the reduction of opioid tolerance. Based on our results the development of a new clinically important, safe analgesic agent might be possible., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The synthesis and the effect of a combination of 6-glycine and 14-phenylpropoxy substitutions in N-methyl- and N-cycloproplymethylmorphinans on biological activities are described. Binding studies revealed that all new 14-phenylpropoxymorphinans (11-18) displayed high affinity to opioid receptors. Replacement of the 14-methoxy group with a phenylpropoxy group led to an enhancement in affinity to all three opioid receptor types, with most pronounced increases in δ and κ activities, hence resulting in a loss of μ receptor selectivity. All compounds (11-18) showed potent and long-lasting antinociceptive effects in the tail-flick test in rats after subcutaneous administration. For the N-methyl derivatives 13 and 14, analgesic potencies were in the range of their 14-methoxy analogues 9 and 10, respectively. Even derivatives 15-18 with an N-cyclopropylmethyl substituent acted as potent antinociceptive agents, being several fold more potent than morphine. Subcutaneous administration of compounds 13 and 14 produced significant and prolonged antinociceptive effects mediated through peripheral opioid mechanisms in carrageenan-induced inflammatory hyperalgesia in rats.

Catenins (alpha, ss, and gamma) are a group of intracellular cell adhesion molecules that unite cytoskeleton with extracellular adhesion system. Abnormal expression of these molecules may have prognostic relevance in various carcinomas, including differentiated thyroid carcinoma (DTC). We have, therefore, evaluated the prognostic value of alpha-, ss-, and gamma-catenins along with traditional risk factors in 206 consecutive DTC patients by immunohistochemistry. Papillary carcinomas showed normal staining pattern for alpha-, ss-, and gamma-catenins in 124 (60%), 136 (67%), and 94 (46%) cases, respectively. Follicular carcinomas expressed alpha-, ss-, and gamma-catenins normally in 16 (48%), 18 (55%), and 8 (32%) cases, respectively. Follicular type of tumor showed more often reduced staining for all catenins than papillary carcinoma (P: = 0.009, P: = 0.004, and P: = 0.002, respectively). Age (>60 yr) and pTNM-stage were related to reduced alpha- and ss-catenin expression levels (P: = 0.027 and P: = 0.026, respectively) and larger size of the tumor to reduced ss- and gamma-catenin expressions (P: = 0.039 and P: = 0.007, respectively). Nodal metastases at the time of primary treatment related to reduced alpha-catenin expression and distal metastases to reduced ss- and gamma-catenin staining signals (P: = 0.022, P: = 0.014, and P: = 0.039, respectively). Reduced alpha-catenin associated with tumor recurrence (P: = 0.002) and reduced ss-catenin with cancer-related mortality (P: = 0.005). The multivariate analysis for recurrence-free survival showed that alpha-catenin and serum thyroglobulin level 1 yr after primary treatment were prognostic of recurrent disease (hazards ratio, 3.42, P: = 0.022; and hazards ratio, 10.03, P: = 0.0001). In addition, alpha-catenin retained its prognostic significance in low-stage patients (P: = 0.0151). We propose that the evaluation of alpha-catenin expression by immunohistochemistry in DTC patients has prognostic value in addition to that obtained by traditional prognostic factors.

CD44 was detected with an antibody recognizing all forms of CD44 (CD44 standard) and others specific for its v3 and v6 variant isoforms; their prognostic value was evaluated in 213 patients with differentiated thyroid carcinoma (DTC). The staining patterns of CD44 standard (s) and CD44v6 in tumour tissue were quite similar, 176 cases (83%) being highly positive for CD44s and 153 cases (72%) for CD44v6. Only 18 (9%) tumours showed high expression of CD44v3. Papillary carcinomas were significantly more often high expressors of CD44s and CD44v6 than follicular carcinomas (p<0.001 for both). Age older than 60 years, distant metastases, and advanced pTNM stage were related to loss of expression of CD44s (p<0.001, p=0.021, and p=0.003, respectively). Tumour recurrence and cancer-related mortality were related to the reduced level of CD44s (p=0.049 and p=0.042). CD44v3 did not associate with any of the clinicopathological factors. In univariate analysis, CD44s was the only significant prognostic factor for disease-free survival (p=0.0488). In multivariate analysis, CD44s and thyroglobulin level were significant prognostic factors for disease-free survival (p=0.040 and p<0.001, respectively). The reduced level of CD44s in DTC patients seems to be an independent prognostic factor for unfavourable disease outcome., (Copyright 2000 John Wiley & Sons, Ltd.)

Results obtained by the indirect zonal isotropic uniform random (IUR) estimation were compared with those obtained by the direct point and interception counting methods on vertical (VS) or IUR sections in a stereological study of bovine articular cartilage collagen fibrils at the ultrastructural level. Besides comparisons between the direct and indirect estimations (direct IUR vs indirect IUR estimations) and between different sampling methods (VS vs IUR sampling), simultaneous comparison of the 2 issues took place (direct VS vs indirect IUR estimation). Using the direct VS method, articular cartilage superficial zone collagen volume fraction (Vv 41%) was 67% and fibril surface density (S(v) 0.030 nm2/nm3) 15% higher (P < 0.05) than values obtained by the indirect IUR method (V(v) 25 % and Sv 0.026 nm2/nm3). The same was observed when the direct IUR method was used: collagen volume fraction (Vv 40 %) was 63 % and fibril surface density (Sv 0.032 nm2/nm3) 21 % higher (P < 0.05) than those obtained by the indirect IUR technique. Similarly, in the deep zone of articular cartilage direct VS and direct IUR methods gave 50 and 55% higher (P < 0.05) collagen fibril volume fractions (Vv 43 and 44% vs 29%) and the direct IUR method 25% higher (P < 0.05) fibril surface density values (Sv) 0.025 vs 0.020 nm2/nm3) than the indirect IUR estimation. On theoretical grounds, scrutiny calculations, as well as earlier reports, it is concluded that the direct VS and direct IUR methods systematically overestimated the Vv and Sv of collagen fibrils. This bias was due to the overprojection which derives from the high section thickness in relation to collagen fibril diameter. On the other hand, factors that during estimation tend to underestimate Vv and Sv, such as profile overlapping and truncation ('fuzzy' profiles), seemed to cause less bias. As length density Lv and collagen fibril diameter are minimally biased by the high relative section thickness, the indirect IUR method, based on utilisation of these estimates, is here regarded as representing a 'gold standard'. The sensitivity of these 3 methods was also tested with cartilage from an in vitro loading experiment which caused tissue compression. In the superficial zone of articular cartilage Vv and Sv of collagen fibrils increased (P < 0.05). This difference in the stereological estimates was only detected by the indirect IUR estimation but not by the direct VS or direct IUR methods. This indicated that the indirect IUR estimation was more sensitive than the direct VS or direct IUR estimations. On the basis of these observations, the indirect zonal IUR estimation can be regarded as the technique of choice in the electron microscopic stereology of cartilage collagen.

Infiltrating cells from the dermis can be literated without serious damage to the cell surface by cautious enzymatic treatment in a cell extractor. A new rapid method has been worked out measuring lymphocyte stimulation by detecting changes in the chromatin's birefringence. The chromatin's anisotropy depended upon antigen concentration, incubation time at 37 degrees and was unsignificantly influenced by the samples' cellularity, between 4 x 10(5) and 4 x 10(7) cells per ml. Therefore, it was concluded that the stimulated lymphocytes in the eczematous infiltrate can be detected by birefringence after incubating for 30 min with proper concentrations of the antigen.