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Purpose: Aerobic exercise produces beneficial outcomes in patients with low back pain and partially attenuates the fibrotic changes to the multifidus in a model of intervertebral disc (IVD) degeneration. More targeted exercise might be required to fully attenuate these fibrotic alterations. This study aimed to investigate whether activation of the multifidus induced by neurostimulation could reduce fibrosis of the multifidus in a model of IVD degeneration in sheep. Methods: IVD degeneration was induced in 18 merino sheep via a partial thickness unilateral annulus fibrosus lesion to the L1/2 and L3/4 IVDs. All sheep received an implantable neurostimulation device that provides stimulation of the L2 medial branch of the dorsal ramus. Three months after surgery, the animals were assigned to Injury or Activated groups. Activated animals received neurostimulation and the Injury group received no stimulation. Six months after surgery, the multifidus was harvested at L2 and L4. Van Gieson's, Sirius Red and immunofluorescence staining for Collagen-I and -III and quantitative PCR was used to examine fibrosis. Muscle harvested from a previous study without IVD injury was used as a control. Results: Neurostimulation of the multifidus attenuated IVD degeneration dependent increases in the connective tissue, including Collagen-I but not Collagen-III, compared to the Injury group at L4. No measures of the multifidus muscle at L2, which received no stimulation, differed between the Injury and Activated groups. Conclusions: These data reveal that targeted activation of the multifidus muscle attenuates IVD degeneration dependent fibrotic alterations to the multifidus. [ABSTRACT FROM AUTHOR]

Background: Coronavirus has serially overtaken our metropolitan hospitals. At peak, patients with acute respiratory distress syndrome may outnumber mechanical ventilators. In our Miami Hospital System, COVID‐19 cases have multiplied for 4 weeks and elective surgery has been suspended. Methods: An Otolaryngologic Triage Committee was created to appropriately allocate resources to patients. Hospital ethicists provided support. Our tumor conference screened patients for nonsurgical options. Patients were tested twice for coronavirus before performing urgent contaminated operations. N95 masks and protective equipment were conserved when possible. Patients with low‐grade cancers were advised to delay surgery, and other difficult decisions were made. Results: Hundreds of surgeries were canceled. Sixty‐five cases screened over 3 weeks are tabulated. Physicians and patients expressed discomfort regarding perceived deviations from standards, but risk of COVID‐19 exposure tempered these discussions. Conclusions: We describe the use of actively managed surgical triage to fairly balance our patient's health with public health concerns. [ABSTRACT FROM AUTHOR]

8 Robson, M, Chew D, Aalast Van S. Intrinsic acute renal failure (ARF) associated with non-steroidal anti-inflammatory drug (NSAID) use in juvenile cats undergoing routine desexing- 16 cases 1998-2005. Pain behaviors before and after treatment of oral disease in cats using video assessment: a prospective, blinded, randomized clinical trial. We are writing on behalf of our respective organisations with regards to the paper " I Acute kidney injury in 18 cats after subcutaneous meloxicam and an update on non-steroidal anti-inflammatory drug usage in feline patients in Australia i ", published in the AVJ 2023 Mar;101 (3):90-98. [Extracted from the article]

Summary: Background: There is no information directly comparing midazolam with guaifenesin when used in combination with an alpha‐2 agonist and ketamine to maintain anaesthesia via i.v. infusion in horses. Objectives: To compare ketamine–medetomidine–guaifenesin with ketamine–medetomidine–midazolam for total intravenous anaesthesia (TIVA) in young horses anaesthetised for computerised tomography. Study design: Prospective, randomised, blinded, crossover trial. Methods: Fourteen weanlings received medetomidine 7 μg/kg bwt i.v. and anaesthesia was induced with ketamine 2.2 mg/kg bwt i.v. On two separate occasions horses each received infusions of ketamine 3 mg/kg bwt/h, medetomidine 5 μg/kg bwt/h, guaifenesin 100 mg/kg bwt/h (KMG) or ketamine 3 mg/kg bwt/h, medetomidine 5 μg/kg bwt/h, midazolam 0.1 mg/kg bwt/h (KMM) for 50 min. Cardiorespiratory variables and anaesthetic depth were assessed every 5–10 min. Recovery times after the infusions ceased were recorded and recovery quality was assessed using a composite score system (CSS), simple descriptive scale (SDS) and visual analogue scale (VAS). Multivariable models were used to generate mean recovery scores for each treatment and each recovery score system and provide P‐values comparing treatment groups. Results: Anaesthesia was uneventful with no difference in additional anaesthetic requirements and little clinically relevant differences in cardiopulmonary variables between groups. All horses recovered without incident with no significant difference in recovery times. Quality of the anaesthetic recovery was significantly better for the KMM group compared with the KMG group using the CSS (P<0.001), SDS (P<0.001) and VAS (P<0.001). Main limitations: No surgical stimulus was applied and study animals may not represent general horse population. Conclusion: Midazolam is a suitable alternative to guaifenesin when co‐infused with ketamine and medetomidine for anaesthesia in young horses undergoing noninvasive procedures. Both infusions produce a clinically comparable quality of anaesthesia; however, recovery from anaesthesia is of a better quality following an infusion of ketamine–medetomidine–midazolam. [ABSTRACT FROM AUTHOR]

Abstract: Micro‐to‐nanoscale surface topographies of orthopaedic and dental implants can affect fluid wetting and biological response. Nanoscale features can be superimposed on microscale roughness of titanium (Ti) surfaces at high temperatures, resulting in increased osteoblast differentiation. However, high temperatures can compromise mechanical properties of the bulk material. Here, we have developed a novel low‐temperature microwave hydrothermal (MWHT) oxidation process for nanomodification of microrough (SLA) Ti surfaces. Nanoscale protuberances (20 –100 nm average diameter) were generated on SLA surfaces via MWHT treatment at 200°C in H2O, or in aqueous solutions of H2O2 or NH4OH, for times ranging from 1 to 40 h. The size, shape, and crystalline content of the nanoprotuberances varied with the solution used and treatment time. The hydrophilicity of all MWHT‐modified surfaces was dramatically enhanced. MG63 and normal human osteoblasts (NHOsts) were cultured on MWHT‐treated SLA surfaces. While most responses to MWHT‐modified surfaces were comparable to those seen on SLA controls, the MWHT‐generated nanotopography reduced osteocalcin production by NHOst cells, suggesting that specific nanotopographic characteristics differentially mediate osteoblast phenotypic expression. MWHT processing provides a scalable, low‐temperature route for tailoring nanoscale topographies on microroughened titanium implant surfaces with significantly enhanced wetting by water, without degrading the microscale surface structure of such implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 782–796, 2018. [ABSTRACT FROM AUTHOR]

Background Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and minorities have the worst survival. However, the molecular mechanisms underlying survival disparities have not been elucidated. Methods In a retrospective study, we assessed association between HNSCC early death (<2 years) and 208 somatic mutations of 10 cancer-related genes in 214 patients: 98 non-Hispanic whites (46%), 72 Hispanic whites (34%), and 44 African Americans (20%). Results Hispanic whites and African Americans had significantly higher mutation rates for EGFR, HRAS, KRAS, and TP53. HNSCC early death was significantly associated with 3+ mutations (odds ratio [OR] = 2.78, 95% confidence interval [CI] = 1.16, 6.69), NOTCH1 mutations in non-Hispanic whites (OR = 5.51; 95% CI = 1.22-24.83) and TP53 mutations in Hispanic whites (OR = 3.84; 95% CI = 1.08-13.68) in multivariable analysis adjusted for age, sex, tumor site, and tumor stage. Conclusion We have provided the proof-of-principal data to link racial/ethnic-specific somatic mutations and HNSCC prognosis and pave the way for precision medicine to overcome HNSCC survival disparities. © 2016 Wiley Periodicals, Inc. Head Neck 38:1234-1241, 2016 [ABSTRACT FROM AUTHOR]

Cellular metabolic pathways are paradigms for the rapid and waste-free conversion of molecules into useful products through multiple enzyme-catalyzed steps (cascade reactions). Attempts to establish efficient cascade reactions for technological applications have focused on mimicking nature's high degree of organization by controlling the positioning of enzymes through immobilization in tailor-made compartments. The present work utilized peptide-mediated layer-by-layer mineralization as a facile and generic method for the compartmentalisation of multi-enzyme systems in nanoscale silica layers. It is demonstrated that, in a multilayer system, the overall rate of the reaction cascade was primarily affected by the placement of the enzyme catalyzing the first step, with the placement of the enzyme possessing the lowest catalytic efficiency also being an important factor. As the rate-limiting enzymes were positioned closer to the external silica surface, the overall rate of cascade reactions increased. Furthermore, distributing the enzymes into different adjacent silica compartments yielded higher overall cascade reaction rates compared to placement of the enzymes into the same silica layer. The synthetic methods and kinetic analyses presented here provide guidance for improving the performance of immobilized multi-enzyme systems for a wide range of technological applications. [ABSTRACT FROM AUTHOR]

Certain patterns of "lymphoma masquerade" are examined, where the diagnosis is very difficult to establish. The presence of prolonged symptoms prior to the acute event or indolent slow healing wounds should alert clinicians to the possibility that lymphoma may be involved. Localizing tumors in order to make a tissue diagnosis is one potential problem encountered even with computerized tomography, but magnetic resonance imaging has been helpful in demonstrating the presence of tumor mass. Included in this report is an unusual series of non-Hodgkin's lymphoma cases in which there was not an obvious tumor. Three patients presented with symptoms and findings of deep neck abscess, two of which were associated with an esophageal perforation or tracheoesophageal fistula. The other cases involved chronic sinusitis and an apparent viral polyneuropathy affecting multiple cranial nerves. Treatment of these non-Hodgkin's lymphomas and techniques for establishing the pathological diagnosis are discussed. [ABSTRACT FROM AUTHOR]

Reconstruction for severe stenosis of the hypopharynx, laryngeal inlet, and/or cervical esophagus is a challenging problem for the surgeon and his patient who want to avoid total laryngectomy. We reviewed the case records of eight patients and the relevant published literature in an effort to define the requirements for success and the causes of failure. A variety of surgical techniques were used. Seven of 8 patients eat a normal or near normal diet. Two of 4 patients, who sustained laryngeal damage at the time of initial injury, required total laryngectomy because of persistent aspiration. The 2 remaining patients and the 4 patients, who did not sustain laryngeal damage at the time of injury, speak with a good voice. Total laryngectomy should be reserved for those patient who cannot be rehabilitated following optimal reconstruction. [ABSTRACT FROM AUTHOR]

Intranasal ethmoidectomy is one of the most difficult operations to teach residents. An accurate knowledge of the regional topographic anatomy is of utmost importance. Friedman and Kerr reported complications of 1000 cases of consecutive intranasal ethmoidectomies performed at the Mayo Clinic from 1957 to 1972. The complication rate was 2.8%. Meningitis, cerebrospinal fluid rhinorrhea, loss of olfaction, and nasolacrimal duct obstruction were reported. No blindness, loss of occular motility, excision of brain tissue or intracranial vessel damage occurred in their series. We are reporting a series of 8 cases of very rare complications following intranasal ethmoidectomies: 1. Optic nerve damage resulting in total blindness (3 cases). 2. Loss of occular motility (2 cases). 3. Cerebrospinal fluid leak resulting in 8 episodes of pseudomonas meningitis and epidural abscess (1 case). 4. Cavernous sinus--internal carotid artery fistula (1 case). 5. Anterior cranial fossa brain damage resulting in death (1 case). These cases, which were either referred to us or came up for our review, are described in detail. A search of the world literature demonstrates a lack of emphasis on such complications. The pitfalls of intranasal ethmoidectomy are considered and ways to avoid such dreadful complications are discussed. [ABSTRACT FROM AUTHOR]

The ability to synthesize large quantities of 3-D microparticles with tunable adhesion is critically important for a variety of mature and emerging technologies, such as for paints, inks, chemical/water purification, drug delivery, cell manipulation, and assembly of hierarchical structures. Nature provides impressive examples of sustainable, complex-shaped microparticles with chemistries and structures tailored for adhesion, among the most common of which are pollen grains. We have recently used a surface sol-gel (SSG) coating process to generate iron oxide replicas of sunflower pollen grains. While these replicas exhibited multimodal adhesion, the tailorability and predictability of such adhesion was not examined. In the present paper, the layer-by-layer SSG process has been used to carefully adjust the amount of iron oxide deposited onto the pollen grains. Controlled-atmosphere thermal treatments then yielded freestanding replicas with tailored hematite (α-Fe2O3) or magnetite (Fe3O4) contents. The 3-D morphology of the starting pollen was well-preserved in the all-oxide replicas, and the shrinkage upon firing could be controlled by increasing the number of Fe-O-bearing layers deposited on the pollen. While the shortrange van der Waals (VDW) adhesion of the oxide replicas to a variety of surfaces was lower than for the larger starting pollen grains, this difference was not due to shrinkage of the replicas. Analyses with a simple Hamaker model indicated that VDW adhesion of the oxide replicas was governed by the contact of oxide nanocrystals located on the spine tips (as opposed to the curvature of the entire spine tip). The longer-range attraction to a magnetic substrate could be tailored independently of the short-range VDW attraction by controlling the magnetite content of the replicas, and a simple and effective model for describing such magnetic attraction was developed. This work demonstrates that sustainable pollen microparticles can be converted into high-fidelity 3-D oxide replicas with predictable and tailorable multimodal adhesion. [ABSTRACT FROM AUTHOR]

Reasons for performing study Prophylactic digital hypothermia reduces the severity of acute laminitis experimentally but there is no evidence for its efficacy as a treatment once lameness has already developed. Objectives To investigate the therapeutic effects of digital hypothermia, applied after the onset of lameness, in an experimental acute laminitis model. Study design Randomised, controlled (within subject), blinded, experimental trial. Methods Eight Standardbred horses underwent laminitis induction using the oligofructose model. Once lameness was detected at the walk, one forelimb was continuously cooled ( CRYO), with the other forelimb maintained at ambient temperature ( NON-RX). Dorsal lamellar sections (proximal, middle and distal) harvested 36 h after the onset of lameness/initiation of cryotherapy were analysed by 2 blinded observers: laminitis pathology was scored (0 [normal] to 4 [severe]) and morphometric analyses performed. Results Median (interquartile range) histological scores were greater (P<0.05) in NON-RX (proximal 2.8 [2.5-4]; middle 3.5 [2-4]; distal 2.5 [2-3.8]) compared with CRYO limbs (proximal 0.5 [0.5-1.4]; middle 1 [0.6-1]; distal 0.75 [0.5-1]). There was complete physical separation of lamellar dermis from epidermis (score of 4) in 4 of the NON-RX feet at one or more section level(s), which was not observed in any CRYO sections. Histomorphometry was thus limited to sections that remained intact; there was a trend of increased total ( TELL) and secondary ( SELL) epidermal lamellar length and decreased secondary epidermal lamellar width ( SELW) in NON-RX limbs compared with CRYO at all 3 levels; differences were significant (P<0.05) for SELL and SELW in the distal sections. Conclusions Digital hypothermia reduced the severity of lamellar injury and prevented lamellar structural failure (complete dermoepidermal separation) when initiated at the detection of lameness in an acute laminitis model. This study provides the first evidence to support the use of therapeutic digital hypothermia as a treatment for acute laminitis. [ABSTRACT FROM AUTHOR]

Advances in molecular cytogenetics have provided the opportunity to study events during prophase I of meiosis. Immunofluorescent localization of different meiotic protein components were used to characterize the early stages of the first meiotic division in horse spermatocytes. The frequency and distribution of recombination events during prophase I were investigated using the mutL homolog 1 (MLH1) protein that is known to be associated with these events. The frequency and distribution of MLH1 foci were investigated in pachytene nuclei of 6 fertile stallions, and the average relative synaptonemal complex length was found to be highly correlated with the average number of MLH1 foci. The frequency and distribution of MLH1 foci were found to closely correspond to the frequency and distribution of chiasmata on metaphase I chromosomes, and genetic length, calculated from MLH1 foci data, for the whole genome was 2,505.5 cM. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A scalable, low-cost process for fabricating copper-based microwave components on flexible, paper-based substrates is demonstrated. An inkjet printer is used to deposit a catalyst-bearing solution (tailored for such printing) in a desired pattern on commercially-available, recyclable, non-toxic (Teslin®) paper. The catalystbearing paper is then immersed in an aqueous copper-bearing solution to allow for electroless deposition of a compact and conformal layer of copper in the inkjet-derived pattern. Meander monopole antennas comprised of such electroless-deposited copper patterns on paper exhibited comparable performance as for antennas synthesized via inkjet printing of a commercially-available silver nanoparticle ink. However, the solution-based patterning and electroless copper deposition process avoids nozzle-clogging problems and costs associated with noble metal particle-based inks. This process yields compact conductive copper layers without appreciable oxidation and without the need for an elevated temperature, post-deposition thermal treatment commonly required for noble metal particle-based ink processes. This low-cost copper patterning process is readily scalable on virtually any substrate and may be used to generate a variety of copper-based microwave devices on flexible, paper-based substrates. [ABSTRACT FROM AUTHOR]

Reasons for performing the study The use of alfaxalone and medetomidine administered as an i.v. infusion to maintain anaesthesia has not previously been reported in the horse. Objectives To investigate the use of alfaxalone in hydroxpropyl-beta-cyclodextrin ( Alfaxan) and medetomidine infusion as a field anaesthetic for short-term surgical procedures in the horse. Hypothesis Alfaxalone-medetomidine anaesthesia is suitable for short-term field anaesthesia in horses. Methods Eleven healthy colts underwent 45 min of anaesthesia with an i.v. infusion of alfaxalone (2 mg/kg bwt/h) and medetomidine (5 μg/kg bwt/h) for routine field castration. Horses were premedicated with i.v. acepromazine (0.03 mg/kg bwt), medetomidine (7 μg/kg bwt) and guaiphenesin (35 mg/kg bwt) before i.v. induction with alfaxalone (1 mg/kg bwt). Colts were intubated with an endotracheal tube and 100% oxygen insufflated at 10 l/min. The physiological variables monitored included pulse rate, respiratory rate, direct arterial blood pressure, arterial blood gases and the quality of the inductions and recoveries were scored. Results Overall, the anaesthetic period and surgical conditions were acceptable and the quality of the anaesthetic inductions and recoveries was good to excellent. All colts stood on their first attempt (mean ± s.d.) 37 ± 13.5 min after the infusion was stopped. During anaesthesia, cardiopulmonary data, presented as range of mean values at each time point were: heart rate: 45-47 beats/min; mean blood pressure: 104-112 mm Hg; respiratory rate: 8 breaths/min; PaO2: 117-172 mm Hg; PaCO2: 50-56 mm Hg and pH 7.34-7.37. Conclusions and potential relevance The co-administration of alfaxalone and medetomidine as an i.v. infusion after anaesthetic induction with alfaxalone was suitable for short-term field anaesthesia in the horse. [ABSTRACT FROM AUTHOR]

A preconcentration neutron activation analysis method has been developed for the determination of trace levels of Cu in natural waters including seawater with an absolute detection limit of 0.106 μg. The method involves the preconcentration of Cu onto Amberlite XAD-4 resin coated with 1-(2-thiazolylazo)-2-naphthol using reversed-phase extraction chromatography (RPEC). Copper is assayed through its neutron activation product Cu (half-life = 5.10 min) by direct irradiation of the resin bed. Factors affecting the uptake of Cu onto the ligand-impregnated resin have been investigated; these include flow rate, pH, column height, presence of other trace elements, major elements, and interfering matrix. The RPEC-NAA method has been validated by analyzing NIST and NRC water reference materials. [ABSTRACT FROM AUTHOR]

This article describes the occurrence of bilateral dentigerous cysts in a 1-year-old entire male Standardbred horse. Computer tomography (CT) with a positive contrast CT fistulogram was used to accurately define the anatomy of the cysts preoperatively. Conventional surgical techniques were used to remove the cysts under general anaesthesia. The CT studies were able to precisely define the margins of the cysts and facilitated uncomplicated surgical excision. Follow-up examination of the animal revealed excellent cosmesis at the surgical site. Histology was used to confirm the diagnosis of bilateral dentigerous cysts. Preoperative CT studies are invaluable to precisely define the anatomical locations of the dental anomalies associated with dentigerous cysts and thereby allow confident and uncomplicated excision. Dentigerous cysts may occur bilaterally in horses. [ABSTRACT FROM AUTHOR]

Background: Head and neck squamous cell carcinoma (HNSCC) is a debilitating and deadly disease largely due to late stage diagnosis. Prior work indicates that soluble CD44 (solCD44) and total protein may be useful diagnostic markers for HNSCC. In this study we combine the markers solCD44, IL-8, HA, and total protein with demographic and risk factor data to derive a multivariate logistic model that improves HNSCC detection as compared to our previous data using biomarkers alone. Methods: We performed the solCD44, IL-8, HA, and total protein assays on oral rinses from 40 HNSCC patients and 39 controls using ELISA assays. Controls had benign diseases of the upper aerodigestive tract and a history of tobacco or alcohol use. All subjects completed a questionnaire including demographic and risk factor data. Results: Depending on cancer subsite, differences between cases and controls were found for all markers. A multivariate logistic model including solCD44, total protein and variables related to smoking, oral health and education offered a significant improvement over the univariate models with an AUC of 0.853. Sensitivity ranged from 75-82.5% and specificity from 69.2-82.1% depending on predictive probability cut points. Conclusion: A multivariate model, including simple and inexpensive molecular tests in combination with risk factors, results in a promising tool for distinguishing HNSCC patients from controls. Impact: In this case-control study, the resulting observations led to an unprecedented multivariate model that distinguished HNSCC cases from controls with better accuracy than the current gold standard which includes oral examination followed by tissue biopsy. Since the components are simple, noninvasive, and inexpensive to obtain, this model combining biomarkers, risk factor and demographic data serves as a promising prototype for future cancer detection tests. [ABSTRACT FROM AUTHOR]

Background Head and neck squamous cell carcinoma (HNSCC) is a devastating disease usually diagnosed at a late stage when cure rates are 40%. We examined a simple and inexpensive molecular tool that may aid HNSCC detection. Methods Building on prior findings that total protein levels are elevated in 102 HNSCC cases versus 84 control subjects, we further analyzed these levels with respect to important risk and demographic variables and compared the results to soluble CD44 (solCD44). Using multivariate adaptive regression splines (MARSs)-logit modeling and logistic regression, we determined whether total protein, solCD44, or the combination best identifies HNSCC. Results Combined higher levels of solCD44 and protein were significantly associated with HNSCC (odds ratio [OR] = 24.90; 95% confidence interval [CI], 9.04-68.57; area under the curve [AUC] = 0.786). A model including protein plus solCD44 resulted in a better area (AUC 0.796) than either marker alone. Conclusion Oral rinse levels of solCD44 and protein seem to hold promise for detection of HNSCC. © 2011 Wiley Periodicals, Inc. Head Neck, 2012 [ABSTRACT FROM AUTHOR]

Background. We reviewed management of the cervical lymph nodes in patients with Merkel cell carcinoma (MCC) of the head and neck. Methods. Records of 15 patients with MCC of the head and neck area were evaluated for the type of surgical treatment, including wide local excision, sentinel lymph node (SLN) biopsy, neck dissection, postoperative radiation therapy, and clinical outcomes. Results. Median follow-up was 24 months (range, 5–84 months). Ten patients were treated with wide local excision plus SLN, with or without neck dissection. Five patients were treated with wide local excision only or wide local excision plus neck dissection. One patient died of distant metastases (7%), and 14 patients remain alive (93%), over a mean follow-up of 24 months. Conclusion. Wide excision and SLN biopsy for primary MCC with N0 neck is feasible for early-stage, previously untreated lesions. SLN biopsy was helpful in determining the nodal levels to be dissected or irradiated. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [ABSTRACT FROM AUTHOR]

The article discusses the poor prognosis of African Americans and misfortunate individuals on head and neck (HN) cancer in the U.S. It notes that cancer survival is based on race, ethnicity, and socioeconomic status (SES). It mentions that HN carcinoma results to high mortality rate. Moreover, it highlights that surgical treatment and chemotherapy offers improvement to cancer patients.

This article investigates how understanding the theory of organic chemistry facilitates the total synthesis of organic compounds. After locating the philosophical significance of this question within the methodology or epistemology of applied science, I summarize the results of previous work on this issue—roughly that theoretical organic chemistry underwrites a sequence of heuristic policies that help to isolate plausible synthetic routes from the array of possibilities provided by structural or descriptive organic chemistry. While this prior account makes a solid start, it does not capture all of the ways that the theory of organic chemistry contributes to total synthesis. This article aspires to enrich this account by exploring some additional ways that theory contributes. More specifically, I investigate how understanding the theory of organic chemistry can facilitate both the development of novel synthetic reactions and the implementation of a synthetic plan. The role of theory in these aspects of total synthesis will be explored by considering a particular, novel synthesis of longifolene. [ABSTRACT FROM AUTHOR]

Organic chemists have been able to develop a robust, theoretical understanding of the phenomena they study; however, the primary theoretical devices employed in this field are not mathematical equations or laws, as is the case in most other physical sciences. Instead it is diagrams, and in particular structural formulas and potential energy diagrams, that carry the explanatory weight in the discipline. To understand how this is so, it is necessary to investigate both the nature of the diagrams employed in organic chemistry and how these diagrams are used in the explanations of the discipline. I will begin this paper by characterizing some of the major ways that structural formulas used in organic chemistry. Next I will present a model of the explanations in organic chemistry and describe how both structural formulas and potential energy diagrams contribute to these explanations. This will be followed by several examples that support my abstract account of the role of diagrams in the explanations of organic chemistry. In particular, I will consider both the appeal to ‘hyperconjugation’ in the explanation of alkene stability and how the idea of ‘ring strain’ was developed to explain the relative stability of cyclic compounds. [ABSTRACT FROM AUTHOR]

Background. Black Americans are adversely affected by many types of malignancies. Methods. We reviewed data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program to evaluate racial disparities in head and neck cancer incidence, mortality, and survival. Results. Head and neck cancer incidence is greater in the black population and peaks at a younger age. The incidence disparity is decreasing over time and is less for cancers of the oral cavity/pharynx (OCP) than for cancers of the larynx. The disparity in survival after diagnosis is substantial for both sites and is increasing over time because of improvement in survival for the white population, but not for the black population. Some, but not all, of the survival disparity is due to more advanced stage at the time of diagnosis within the black population. The age-adjusted mortality rate for black men is approximately twice the rate for white men. Conclusion. Black Americans clearly bear a greater burden from head and neck cancer. The underlying causes are largely unknown, but are most likely due to a complex interplay of differences in access to health care, quality of medical care, biologic/genetic factors, incidence of comorbid conditions, exposure to carcinogens, diet, and cultural beliefs. Prospective studies are needed to define the relative importance of these factors and to inform intervention strategies. © 2007 Wiley Periodicals, Inc. Head Neck, 2008 [ABSTRACT FROM AUTHOR]

Background. Severe swallowing dysfunction is the dominant long-term complication observed in patients treated for head and neck squamous cell carcinoma (HNSCC) with treatment protocols using intensive concurrent chemotherapy with radiation therapy (chemo/XRT). We identified a subset of these patients, who were seen with complete obstruction of the hypopharynx distal to the site of the primary cancer, and in whom we postulate that the obstruction was caused by separable mucosal adhesions rather than obliteration by a mature fibrous stricture. Methods. Seven patients were referred to the senior author with a diagnosis of complete hypopharyngeal obstruction between 1992 and 2001. The diagnosis was confirmed by barium swallow imaging and/or endoscopy before referral in all patients. Patients underwent recanalization by passing a Jesberg esophagoscope under general anesthesia, followed by serial dilations and intensive swallowing therapy. Patient charts were reviewed retrospectively after institutional review board approval. Results. All seven patients were successfully recanalized. No patient had a perforation or other significant complication related to the recanalization procedure or subsequent dilations. Five of the seven patients showed improvement in swallowing at some point after the initial procedure, but just two patients recovered sufficiently to have their gastrostomy tube removed permanently. Conclusions. We conclude that complete hypopharyngeal obstruction secondary to mucosal adhesions is one cause of gastrostomy tube dependence in patients who have been treated with chemo/XRT for HNSCC. It is a difficult problem to treat, but most patients can recover useful swallowing function without undergoing laryngectomy or major surgical reconstruction. The postulated pathophysiology has implications for prevention as well as treatment. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [ABSTRACT FROM AUTHOR]

We report our histologic and immunohistochemical findings in a rare case of cutaneous carcinosarcoma involving the helix of the ear. The tumor exhibited cellular features of both basal cell and squamous cell carcinoma and a malignant mesenchymal component that was consistent with malignant fibrous histiocytoma. The epithelial component exhibited a positive immunohistochemical reaction to cytokeratin and a negative reaction to vimentin, whereas the mesenchymal component showed a positive immunohistochemical reaction to vimentin and a negative reaction to cytokeratin. To the best of our knowledge, this is only the third reported case of a carcinosarcoma of the ear and the second case in which it developed on the helix. [ABSTRACT FROM AUTHOR]

Objectives/Hypotheses: Salvage surgery is widely viewed as a 'double-edged sword.' It is the best option for many patients with recurrent cancer of the upper aerodigestive tract, especially when original therapy included irradiation, yet it may provide only modest benefit at high personal cost to the patient. The stakes are high because alternatives are of limited value. The primary objective of this study was to fully assess the value of salvage surgical procedures in the treatment of local and regional recurrence. The following hypotheses were developed to focus the study design and data analysis. 1) The efficacy of salvage surgery correlates recurrent stage, recurrent site, and time to presalvage recurrence. 2) The economic and noneconomic costs of salvage surgery increase with higher recurrent stage. 3) Information relating the value of salvage surgery to recurrent stage and recurrent site will be useful to these patients and the physicians who treat them. Study Design: Two complimentary methods of investigation were used: a meta-analysis of the published literature and a prospective observational study of patients undergoing salvage surgery for recurrent cancer of the upper aerodigestive tract. Methods: The meta-analysis combined 32 published reports to obtain an estimate of average treatment effect for salvage surgery with regard to survival, disease-free survival, surgical complications, and operative mortality. The prospective observational study included detailed data in 109 patients who underwent salvage surgery. In addition to parameters studied in the meta-analysis, we obtained baseline and interval quality of life data (Functional Living Index for Cancer [FLIC] scores), baseline and interval performance status evaluations (Performance Status Scale for Head and Neck Cancer Patients [PSS head and neck scores]), length of hospital stay, and hospital and physician charges, and related this data primarily to recurrent stage, recurrent site, and time to presalvage recurrence. Results: The weighted average of 5-year survival in the meta-analysis was 39% in 1,080 patients from 28 different institutions. In the prospective study, median disease-free survival was 17.9 months in 109 patients, and this correlated strongly with recurrent stage, weakly with recurrent site, and not at all with time to presalvage recurrence. Noneconomic costs for patients and economic costs correlated with recurrent stage, but not with site. Baseline FLIC and PSS head and neck scores correlated with recurrent stage, but not with site. After salvage surgery the percentage of patients reaching or exceeding baseline was 51% for FLIC scores, and this differed significantly with recurrent stage. Postoperative interval 'success' in PSS head and neck subscale scores for diet and eating in public also correlated with recurrent stage. Conclusions: Overall, the expected efficacy for salvage surgery in patients with recurrent head and neck cancer was surprisingly good, but success was limited and costs were great in stage III and, especially, in stage IV recurrences. A strong correlation of efficacy and noneconomic costs with recurrent stage allowed the creation of expectation profiles that may be useful to patients. Additional systematic clinical research is needed to improve results. In the end, the decision to undergo salvage surgery should be a personal choice made by the patient after honest and compassionate discussion with his or her surgeon. [ABSTRACT FROM AUTHOR]

Reports a case of a patient diagnosed to have a giant laryngeal lipoma with a history of voice change and progressive dysphagia. Diagnostic procedures; Pathophysiology of the disease; Treatment.

Wheat and wheat products are more important sources of energy and nutrients in diets of people in many cultures compared to other foods. The daily consumption of wheat is about 200 g/d/person in Western Europe and North America. On the other hand, 400–450 g of wheat and wheat products are consumed daily by average Turkish people. Wheat samples collected from the Iskenderun region in 1995 and 1996 and Ankara and Istanbul regions in 1995 were analyzed for their trace element content by instrumental neutron activation analysis (INAA). In addition, 13 soil samples were collected from the Iskenderun region in 1996. Total soil samples were analyzed by INAA and atomic absorption spectrometry (AAS), EDTA-extractable elements by INAA, and DTPA-extractable elements by AAS. Correlation analysis and enrichment factor calculations were applied to the trace element results. In wheat samples, a strong correlation was found between the elements such as Sc, La, Sm, Rb, and K whose main source is soil. The concentration of Se appeared to show larger variations among different regions. No significant correlation was observed for elements such as As and Se whose main sources in the atmosphere are anthropogenic activities. [ABSTRACT FROM AUTHOR]

Higher plasma lycopene concentrations have been associated with a reduced risk of several chronic diseases. Determinants of lycopene concentrations in humans have received limited attention. We had blood lycopene concentrations and lycopene consumption data available from 111 participants in a two-center cancer prevention trial involving beta-carotene and examined determinants of plasma lycopene levels cross-sectionally. The median plasma lycopene level was 0.59 micromol/L (range 0.07-1.79). Low plasma concentrations of lycopene were associated with the following variables in univariate analyses: study site (Florida lower than Connecticut, P = 0.001), being nonmarried (P = 0.02), having lower income (P = 0.003), being nonwhite race/ethnicity (P = 0.03), having lower dietary lycopene intake (r = 0.29, P = 0.002), having lower plasma cholesterol (r = 0. 43, P = 0.0001) and triglyceride levels (r = 0.26, P = 0.005), and consuming less vitamin C (r = 0.20, P = 0.03). Women had slightly higher plasma lycopene levels than men (0.65 vs. 0.58 micromol/L; P = 0.31), despite lower dietary intake of lycopene (1,040 vs. 1,320 microg/d; P = 0.50). Plasma lycopene levels did not differ in smokers and nonsmokers. In stepwise regression analyses, the determinants of plasma lycopene were plasma cholesterol, dietary lycopene, and marital status; these three variables explained 26% of the variance in plasma lycopene. Relatively few lifestyle and demographic factors were important determinants of plasma lycopene levels, with plasma cholesterol, marital status, and lycopene intake being of greatest importance. [ABSTRACT FROM AUTHOR]