Mechanochemical Solvent-Free One-Pot Synthesis of Poly-Functionalized 5-(Arylselanyl)-1H-1,2,3-triazoles Through a Copper(I)-Catalyzed Click Reaction

A mechanochemistry-driven practical and efficient synthetic protocol for accessing diverse series of biologically relevant poly-functionalized 5-(arylselanyl)-1H-1,2,3-triazoles through copper(I)-catalyzed click reaction between aryl/heteroaryl acetylenes, diaryl diselenides, benzyl bromides, and sodium azide has been accomplished under high-speed ball-milling. Advantages of this method include operational simplicity, avoidance of using solvent and external heating, one-pot synthesis, short reaction time in minutes, good to excellent yields, broad substrate scope, and gram-scale applications. Furthermore, synthesized organoselenium compounds were synthetically diversified to biologically promising selenones.

C(sp)-C(sp3) Bond Formation through Ligand- and Additive-Free CuO-Mediated Decarboxylative Direct Cross-Coupling of Coumarin-/Chromone-3-carboxylic Acids and Terminal Alkynes

A practical and efficient method for the synthesis of functionalized 4-(aryl-/heteroaryl-ethynyl)chroman-2-ones and 2-(aryl-/heteroaryl-ethynyl)chroman-4-ones through copper-catalyzed decarboxylative direct cross-coupling of coumarin-/chromone-3-carboxylic acids with terminal alkynes, leading to the formation of C(sp)-C(sp3) bonds, has been unearthed. Advantages of this protocol include avoidance of any ligands and bases, a broad substrate scope, tolerance of diverse functional groups, and good to excellent yields.

A visible light-driven direct synthesis of industrially relevant glutaric acid diesters from aldehydes

A straightforward and practical method has been developed to access α-substituted glutaric diesters from acrylates and aldehydes using visible light, with Eosin Y facilitating hydrogen atom transfer (HAT) and subsequent Giese-type addition. Also, sunlight has been successfully used as an alternative sustainable light source. The method has also been explored to access substituted 4,5-dihydro-2H-pyridazinones, which have potential biological and industrial applications. Comprehensive mechanistic investigations have been carried out.

Direct Access to Strained Fused Dihalo-Aziridino Quinoxalinones via C3-Alkylation Followed by Tandem Cyclization

Quinoxalinones are a privileged class of compounds, and their structural framework is found in many bioactive compounds, natural compounds, and pharmaceuticals. Quinoxalinone is a promising scaffold for different types of functionalization, and the slight modification of the quinoxalinone skeleton is known to offer a wide range of compounds for drug discovery. Owing to the importance of the quinoxalinone scaffold, we have developed a base-mediated protocol for the C3-alkylation of quinoxalinone followed by tandem cyclization to access novel types of strenuous and fused dihalo-aziridino-quinoxalinone heterocycles via the construction of C-C and C-N bonds. The protocol proved to be simple and practical to access desired fused quinoxalinone heterocycles in excellent yields (up to 98% yield). As an application, the highly functionalized fused dihalo-aziridino-quinoxalinone molecule has been further utilized for mono-dehalogenation under visible light irradiation and selective amide reduction. Moreover, the protocol has also been demonstrated on a gram scale.

Catalyst- and Additive-Free C(sp3)-H Functionalization of (Thio)barbituric Acids via C-5 Dehydrogenative Aza-Coupling Under Ambient Conditions

A one-pot room-temperature-based three-component reaction strategy has been accomplished to access a new series of bio-relevant barbituric/2-thiobarbituric acid hydrazones from the reaction between barbituric/2-thiobarbituric acids, primary aromatic amines, and tert-butyl nitrite in an acetonitrile solvent, without the aid of any catalysts/additives. The ambient reaction conditions can efficiently implement the C(sp³)-H functionalization of barbituric/2-thiobarbituric acids via C-5 dehydrogenative aza-coupling. The process does not require column chromatographic purification; pure products are obtained by simple filtration of the resulting reaction mixture, followed by washing the crude residue with distilled water. The catalyst-free ambient reaction conditions, operational simplicity, broad substrate scope and tolerance for various functional groups, no need for chromatographic purification, good to excellent yields of products within reasonable reaction times in minutes, clean reaction profile, and gram-scale synthetic applicability make this procedure attractive, green, and cost-effective.

Visible Light-Driven and Singlet Oxygen-Mediated Photochemical Cross-Dehydrogenative C3-H Sulfenylation of 4-Hydroxycoumarins with Thiols Using Rose Bengal as a Photosensitizer

A visible light (white light-emitting diode/direct sunlight)-driven photochemical synthesis of a new series of biologically interesting 3-(alkyl/benzylthio)-4-hydroxy-2H-chromen-2-ones has been achieved through a cross-dehydrogenative C₃-H sulfenylation of 4-hydroxycoumarins with thiols at ambient temperature in the presence of rose bengal in acetonitrile under an oxygen atmosphere. The notable features of this newly developed method are mild reaction conditions, energy efficiency, metal-free synthesis, good to excellent yields, use of low-cost materials, and eco-friendliness.

Direct access to α-acyloxycarbonyl compounds and esters via oxidative esterification of aldehydes under visible light

An efficient synthesis of α-acyloxycarbonyl compounds and esters from aldehydes and α-bromocarbonyl compounds/benzyl bromide derivatives via photoredox catalysis has been developed.

Series of Functionalized 5-(2-Arylimidazo[1,2-a]pyridin-3-yl)pyrimidine-2,4(1H,3H)-diones: A Water-Mediated Three-Component Catalyst-Free Protocol Revisited

A water-mediated and catalyst-free practical method for the synthesis of a new series of pharmaceutically interesting functionalized 5-(2-arylimidazo[1,2-a]pyridin-3-yl)pyrimidine-2,4(1H,3H)-diones has been accomplished based on a one-pot multicomponent reaction between arylglyoxal monohydrates, 2-aminopyridines/2-aminopyrimidine, and barbituric/N,N-dimethylbarbituric acids under reflux conditions. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvents, use of water as reaction medium, clean reaction profiles, operational simplicity, ease of product isolation/purification without the aid of tedious column chromatography, good to excellent yields, and high atom-economy and low E-factor.

Effect of leg elevation on healing, venous velocity and ambulatory venous pressure in venous ulceration

Objective: Current treatment of venous leg ulcers (VLU) includes four-layer bandaging, appropriate superficial venous surgery and leg elevation. The aims of this study were to: investigate a device designed to measure leg elevation; assess how long patients elevate; and to assess the effect of elevation on ulcer healing, femoral vein velocity (FVV) and popliteal vein cross-sectional area (PVCSA), and venous pressure.

Patients and methods: A datalogger and accelerometer were manufactured to measure leg elevation. The device was validated in eight control subjects; elevation was measured in 24 patients with VLU. Ulcers were traced over six weeks in 29 patients and elevation measured to correlate healing with elevation. Ten patients and 10 controls underwent duplex measurement of FVV and PVCSA to measure flow in relation to posture; nine patients underwent measurement of venous pressure with postural changes. Non-parametric statistical analysis was used.

Results: The datalogger accurately recorded all episodes of elevation. Median (range) elevation time was 53 (0–350) mins/24 h; correlation between ulcer healing and elevation was poor at 0.103 ( P=0.616, Spearman); change in posture from sitting to supine produced a significant increase in median (range) FVV from 11 (7–24) to 34 (22–66) in VLU ( P=0.005) and 15 (12–34) to 38 (16–69) in controls ( P=0.005, Wilcoxon). Change in posture from supine to 25 degrees elevation produced no change in FVV in either group ( P=0.173 in VLU, P=0.327 in controls, Wilcoxon). In VLU, sitting PVCSA was 1.07 (0.51–1.45) cm2. Supine position significantly reduced the area to 0.46 (0.27–1.01) cm2 ( P=0.005, Wilcoxon). On elevation to 25°, PVCSA was further reduced to 0.28 (0.07–0.63) cm2 ( P=0.058, Wilcoxon). In controls, sitting PVCSA was 0.79 (0.31–1.56) cm2, supine was reduced to 0.46 (0.27–1.09) cm2 ( P=0.047, Wilcoxon) and on elevation was reduced to 0.23 (0.10–0.44) cm2 ( P=0.005, Wilcoxon). Venous pressure standing was 99 (73–116) mmHg, reduced to 76 (53–113) mmHg on sitting ( P=0.084), and further reduced to 23 (7–36) mmHg supine ( P=0.008, Wilcoxon).

Conclusions: Leg elevation in patients with VLU is poor but can be accurately measured. Elevation in the presence of compression may not improve ulcer healing. Postural changes of the leg can produce an increase in deep venous flow and a reduction in venous pressure.

Actinomycosis: an unusual cause of unresectable rectal cancer

We present a very unusual case of a woman with an intrauterine contraceptive device (IUCD) who developed pelvic actinomycosis during long course chemoradiotherapy for rectal cancer, which presented a significant diagnostic challenge and eventually rendered the cancer unresectable. IUCDs are often implicated in the development of pelvic actinomycosis but there is no current evidence or guideline to suggest that they should be removed prior to oncological treatment. Owing to the devastating consequences of this combination of disease, we suggest that it may be prudent to remove IUCDs in this setting.

Nonagenarian surgical admissions for the acute abdomen: who benefits?

INTRODUCTION

Patients 90 years and older form an increasing proportion of the general population. Outcomes of their acute surgical admissions are not well documented.

METHODS AND MATERIALS

Surgical management of 49 consecutive nonagenarian admissions (median age: 92 years) with an acute abdomen was compared with the management and outcome of 50 younger patients (median age: 53.5) admitted with a suspected acute abdomen over the same period.

RESULTS

Nonagenarian group consisted of mainly women (71% vs. 50%; p = 0.003). The use of laboratory investigations and imaging was similar for the patients aged over 90 and the younger patients, although proportionately fewer nonagenarians were investigated by abdominal CT scan (8% vs. 24%). Of the 49 nonagenarian patients admitted, only 4% (n = 2) were operated on. In contrast, 38% (n = 19) of patients aged 50-59 (p = 0.0001) underwent a surgical intervention. A much greater proportion of nonagenarians died in hospital than patients in the 50-59 comparator group (16% nonagenarians vs. 4% comparator patients; p = 0.04). The very large majority of survivors in both age groups were discharged back to their preadmission domicile [39 (95%) nonagenarians vs. 46 (96%) comparator 50-59 year group].

CONCLUSIONS

In this study, when compared with younger patients, very few nonagenarian patients (2%) with a suspected acute abdomen benefited from surgical admission. Instead, the large majority of nonagenarians either died or were discharged back to their home address without surgery.

Results of Treatment of Squamous Cell Carcinoma of Maxillary Sinus: A 26-Year Experience

BACKGROUND

Five-year survival in squamous cell carcinoma of maxillary antrum is low. This article examines the results of various approaches to treatment as given in our hospital in past 26 years.

METHODS

From 1979 to 2005, 379 patients with squamous cell carcinoma of maxillary antrum managed with curative intent were studied. Twenty-eight patients had T2, 237 patients had T3, and 114 had T4 tumors. The N classification was N0 in 316 patients, N1 in 21 patients, N2a in 28 patients and N2b in 14 patients. Treatment to the primary site comprised of surgery (Sx) and radiation therapy (RT) in 284 patients, RT alone in 57 patients and chemotherapy (CTx) with radiotherapy in 38 patients.

RESULTS

There was a difference in survival between patients who underwent Sx with RT compared with patients who received RT alone or CTx with RT. The most common pattern of recurrence was in the primary site, 187 (49.3%) patients. Local control at 3 and 5 years was 71% and 63.8% respectively in Sx with RT, 31.6% and 28% respectively in RT, and 28.9% and 26% in CTx with RT group.

CONCLUSIONS

The type of treatment to the primary site is an important determinant of survival and local control. Surgery with radiation is a better treatment option.

Hotel NHS and the acute abdomen - admit first, investigate later

AIM

To determine the financial consequences of a policy of admission first, followed by definitive investigation for patients with an admission diagnosis of suspected acute abdomen.

RESULTS

Over a 1-month period, 122 patients were admitted with a suspected surgical diagnosis of acute abdomen (55 men, 67 women); age range 16-95 years (median: 56.5). Based on surgical operation required (n = 36), death after admission (n = 6, three postoperative deaths) and/or severe surgical illness (n = 17), 56 required surgical inpatient admission, while 66 did not. The patients who did not require admission spent significantly shorter time in hospital than those who required admission (median: 5 days vs. 8.5 days; p = 0.0000). Total hospital hotel and investigation cost (not including ITU or theatre costs) for all 122 patients was 330,468 pounds. Overall, 205,468 pounds was consumed by these 56 patients who required admission, while 125,000 pounds was spent on 66 patients whose clinical course did not justify admission; 92% of which was spent on hospital hotel costs and 8% on the cost of imaging and/or endoscopy.

DISCUSSION AND CONCLUSION

On a national basis, emergency General Surgery admissions account for 1000 Finished Consultant Episodes per 100,000 population. The findings of this study suggest that this equates to a national NHS spend of 650 million pounds each year, for the hotel costs of patients that could arguably avoid surgical admission altogether. Continuing to admit patients with a suspected acute abdomen first and then requesting definitive investigation makes neither clinical nor economic sense.

Surgery for venous insufficiency: are venous function tests necessary?

Background

The role of duplex imaging and measurement of ambulatory venous pressure (AVP) in the preoperative assessment of patients with venous insufficiency (VI) and primary varicose veins (VV) was investigated.

Methods

Venous incompetence was confirmed by duplex imaging in 58 legs: 38 had VI, demonstrated by eczema, oedema or pigmentation, and 20 had VV and normal skin. AVP was measured from a cannulated dorsal foot vein before and after ten tip-toe exercises. This was repeated following occlusion of the superficial veins by narrow tourniquets. Pressure relief index (PRI) was calculated as the fall in AVP in calf exercise × 90 per cent refilling time in seconds. The criterion for superficial vein surgery was doubling of PRI on superficial vein occlusion.

Results

Superficial venous incompetence (SVI) was confirmed in all legs with duplex imaging. Deep vein incompetence (DVI) was found in 17 legs (45 per cent) with VI and in two (10 per cent) of the VV legs (P = 0·012, χ2 test). Venous function was normal (PRI greater than 1000) in six. Median PRI in patients with VI and VV was 177 and 289, rising to 717 and 1026 respectively after superficial vein occlusion. Initial PRI was significantly lower in patients with DVI (P < 0·001). PRI improved by 135 per cent in SVI and by 318 per cent in legs with DVI (P = 0·01). PRI did not double following superficial venous occlusion in 20 legs (35 per cent) with SVI and in three (16 per cent) with deep incompetence (P = 0·01).

Conclusion

Clinical examination and duplex imaging alone cannot predict who will benefit most from superficial venous surgery. AVP measurement rationalizes decision-making and may avoid unnecessary operations.

Expression of cyclooxygenase isoforms in normal human skin and chronic venous ulcers

Chronic venous ulcers are an example of abnormal wound healing showing chronic inflammation which together with the underlying vascular pathology results in delayed healing. Prostaglandins are among the most important mediators of inflammation. They have proinflammatory effects, predominantly by affecting the vasculature. Cyclooxygenase (COX) is the rate-limiting enzyme in prostanoid synthesis. It is present in two isoforms: COX-1 (constitutive cyclooxygenase) which is produced in the body to maintain normal haemostatic functions, and COX-2 (inducible cyclooxygenase), which is induced during inflammation in response to cytokines. Using immunoenzymatic labelling and western blot analysis, this study has shown that both COX-1 and COX-2 were up-regulated in chronic venous leg ulcers by comparison with normal human skin. De novo appearance of COX-2 in chronic venous ulcers was demonstrated, which is not seen in normal human skin. The main cellular sources of both COX isoforms are macrophages and endothelial cells. COX-2 is also produced by mast cells and fibroblasts. A COX radioimmunoassay showed up-regulation of COX activity in chronic venous ulcers compared with normal skin (p<0.05). Up-regulation of COX-1 in chronic venous leg ulcers could produce prostacyclin, which contributes to angiogenesis. Thus, inhibition of COX-1 by non-steroidal anti-inflammatory drugs (NSAIDs) could increase the local ischaemia and hypoxia associated with chronic venous ulcers. On the other hand, up-regulation of COX-2 is most likely responsible for the persistent inflammation in chronic venous leg ulcers. COX-2 selective inhibitors could therefore be effective in the treatment of chronic venous ulcers.

Rhabdomyosarcoma of nasopharynx

Rhabdomyosarcoma is a highly invasive malignant tumour arising from the mesenchymal tissue. Here, we reported a rare case of embryonal rhadomyosarcoma of nasopharynx with extension to different spaces of base of skull and orbit. Rarity of the case difficulty in diagnosis encourages its reporting.

Giant dentigerous cyst

Dentigerous cyst - a cyst of dental origin, though common in lower jaw is relatively uncommon in upper jaw. Here a 14 years, F, presented with huge swelling of unilateral maxilla and clinicoradiologically diagnosed as dentigerous cyst is being reported along with brief review of literature.

Sustained release of antimicrobial drugs from polyvinylalcohol and gum arabica blend matrix

Synthetic polymers are widely used in biomedical applications. Polymer blends have recently paved their way in this field. An attempt to prepare blend of synthetic polymer polyvinylalcohol and natural macromolecule gum arabica is made in this paper. Characterization of these blends by NMR, DSC and viscoelastic studies reveal preparation of a blend composition with synergistic properties. The blend composition with synergistic properties was used to release various antimicrobial drugs. The duration and release of the drug depends on the amount of drug loaded in the matrix and solubility of the drug in the matrix and release medium. The advantage of this system is that the release kinetics of the drug from the system can be tailored by adjusting plasticizer, homopolymer and crosslinker composition depending on the drug to be released.

Sustained release of ferrous sulfate from polymer-coated gum arabica pellets

Sustained release of ferrous sulfate (FeSO4) from gum arabica pellets has been achieved for 7 h. Release is further sustained for 12 to 600 h by coating the pellets with polyvinyl acetate and ethylene vinyl acetate, respectively. An increase in the amount of gum arabica in the pellets decreases the rate of release due to the gelling property of gum arabica. The gel layer acts as a barrier and retards the rate of diffusion of FeSO4 through the pellet. In coated pellets, an increase in thickness of membrane helps to sustain the release of FeSO4 for a longer duration. Thus, the release of FeSO4 can be sustained for the required duration by adjusting the amount of gum arabica in the pellet and the composition and thickness of polymeric coat. The mechanism of release accordingly varies from Fickian to zero-order and super case II transport.

Synthesis and characterization of aliphatic polyurethane fiber: a potential suture material

Polyurethane fibers were synthesized and characterized by IR, 1H NMR, DSC, and GPC. Their properties as fiber were compared with commercially available sutures of polypropylene, polyamide, polyester, and silk.

Occurrence of polyploidy and multinuclearity in the differentiating liver of chick embryo

Increase in nuclear size in liver has been used as an index of polyploidy. It has long been considered that the occurrence of polyploidy and multinuclearity are characteristics of mammalian liver. The present study shows the occurrence of these phenomena in the liver of birds, so these features are not confined to mammals. 3 classes of nuclear size groups have been identified. The simultaneous occurrence of polyploidy and binuclearity indicates some sort of interrelationship between them.