Applying plastic surgery principles to ovarian tissue transplantation

Ovarian tissue cryopreservation (OTC) and transplantation is an innovative procedure increasingly utilized to help preserve fertility after gonadotoxic treatments especially in cancer patients. Approximately 30% of autotransplanted patients are able to achieve live birth, typically with the help of in-vitro fertilization. Numerous techniques and grafting sites have been described to continue to increase this figure. In the field of plastic surgery, tissue grafting has been successful performed for thousands of years and knowledge in this area has been significantly refined. A qualitative review of the literature using PubMed, Cochrane, SCOPUS and Medline databases was performed to look for articles relating to ovarian tissue transplantation (OTT) and comparisons made to plastic surgery tissue grafting. Many parallels were found between the principles of grafting in plastic surgery and the principles of OTT, including pre-operative patient optimization, suitable donor site selection, tissue harvest and preparation, graft site choice, immobilization of the graft and post-operative care. Consideration of the benefits and risks of using orthotopic versus heterotopic recipient sites is also highly important with regards to graft take, morbidity and ease of access of oocyte collection. We believe that ongoing discussion between disciplines can have the potential to improve knowledge, surgical techniques and patient outcomes.

Free Flap Monitoring, Salvage, and Failure Timing: A Systematic Review

BACKGROUND

 Microsurgical free tissue transfer has become a reliable technique with success rates around 99% and around 5% requiring exploration for vascular compromise. Protocols for flap monitoring between plastic surgery units vary. We aimed to elucidate the time period when monitoring is crucial for flap salvage.

METHODS

 A systematic search of literature was performed in PubMed, Cochrane Library, Medline, and Scopus databases from 1966 to July 2018 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, identifying 3,844 studies with mention of free flap and monitoring or timing or salvage or compromise. Studies were screened for relevance according to predetermined inclusion criteria. Data was extracted from included studies relating to flap type, monitoring, timing and reason for failure, and success of salvage intervention.

RESULTS

 A total of 109 studies featuring 44,031 free flaps were included. A total of 2,549 (5.8%) flaps required return to theater for compromise; 926 (2.1%) were lost and 1,654 (3.7%) were salvaged. In the first 24 hours postoperatively 93.8% of explored flaps are successfully salvaged, by day 2: 83.33%, day 3: 12.1%, and beyond day 4: none were successful. Of the 355 flaps where the cause of failure was reported, 59.5% was venous, 27.9% was arterial, 2.3% was a combination of both, and 10.2% was hematoma or infection. The proportion of flap failures at various recipient sites was highest in the trunk/viscera (7%, 95% confidence interval [CI] 0.00, 0.36), followed by limbs (5%, 95% CI 0.02, 0.08), head and neck (3%, 95% CI 0.02, 0.04), and breast (<1%; 95% CI 0.00, 0.02).

CONCLUSION

 Close flap monitoring is of most value in the first 48 hours postoperatively, facilitating rapid detection of vascular compromise, early salvage, and better outcomes. The location of the flap has implications on its success and certain recipient sites may need particular attention to improve chances of success.

Efficacy and adverse effects of topical chloramphenicol ointment use for surgical wounds: a systematic review

BACKGROUND

Chloramphenicol ointment is often used in plastic and dermatologic surgery as a topical antibiotic for surgical wounds, but evidence regarding its efficacy and side effects is lacking. In addition, anecdotal fear of aplastic anaemia exists from the oral use of this drug. We performed a systematic review of the literature to assess the efficacy and side effect profile of topical chloramphenicol ointment on non-ocular surgical wounds.

METHODS

A systematic search of MEDLINE, EMBASE and the Cochrane Library from inception until 4 September 2017 was undertaken. Clinical studies of topical chloramphenicol ointment use on surgical wounds were included. Studies looking only at ocular use or those not available in full text or English were excluded. The review was conducted adhering to PRISMA guidelines.

RESULTS

After full-text review, five articles were included. Two were randomized controlled trials, one was retrospective case control and two were case studies. There was evidence that chloramphenicol ointment use on surgical wounds produced a non-statistically significant reduction in infection rates. Delayed hypersensitivity and acute oesophagitis were noted as potential side effects of non-ocular topical use. Aplastic anaemia was not reported.

CONCLUSION

There is a paucity of clinical data regarding the use of topical chloramphenicol ointment on surgical wounds. Further randomized controlled trials may be beneficial in order to support or refute its use in this setting.

Methodological quality and reporting of systematic reviews in hand and wrist pathology

The objective of this study was to assess methodological and reporting quality of systematic reviews in hand and wrist pathology. MEDLINE, EMBASE and Cochrane Library were searched from inception to November 2016 for relevant studies. Reporting quality was evaluated using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and methodological quality using a measurement tool to assess systematic reviews, the Assessment of Multiple Systematic Reviews (AMSTAR). Descriptive statistics and linear regression were used to identify features associated with improved methodological quality. A total of 91 studies were included in the analysis. Most reviews inadequately reported PRISMA items regarding study protocol, search strategy and bias and AMSTAR items regarding protocol, publication bias and funding. Systematic reviews published in a plastics journal, or which included more authors, were associated with higher AMSTAR scores. A large proportion of systematic reviews within hand and wrist pathology literature score poorly with validated methodological assessment tools, which may affect the reliability of their conclusions.

LEVEL OF EVIDENCE

I.

Methodological quality assessment of paper-based systematic reviews published in oral health

OBJECTIVES

This study aimed to conduct a methodological assessment of paper-based systematic reviews (SR) published in oral health using a validated checklist. A secondary objective was to explore temporal trends on methodological quality.

MATERIAL AND METHODS

Two electronic databases (OVID Medline and OVID EMBASE) were searched for paper-based SR of interventions published in oral health from inception to October 2014. Manual searches of the reference lists of paper-based SR were also conducted. Methodological quality of included paper-based SR was assessed using an 11-item questionnaire, Assessment of Multiple Systematic Reviews (AMSTAR) checklist. Methodological quality was summarized using the median and inter-quartile range (IQR) of the AMSTAR score over different categories and time periods.

RESULTS

A total of 643 paper-based SR were included. The overall median AMSTAR score was 4 (IQR 2-6). The highest median score (5) was found in the pain dentistry and periodontology fields, while the lowest median score (3) was found in implant dentistry, restorative dentistry, oral medicine, and prosthodontics. The number of paper-based SR per year and the median AMSTAR score increased over time (median score in 1990s was 2 (IQR 2-3), 2000s was 4 (IQR 2-5), and 2010 onwards was 5 (IQR 3-6)).

CONCLUSION

Although the methodological quality of paper-based SR published in oral health has improved in the last few years, there is still scope for improving quality in most evaluated dental specialties.

CLINICAL RELEVANCE

Large-scale assessment of methodological quality of dental SR highlights areas of methodological strengths and weaknesses that can be targeted in future publications to encourage better quality review methodology.

Functional coupling of voltage-dependent L-type Ca2+ current to Ca2+-activated K+ current in pituitary GH3 cells

Ca2+-activated K+ currents (I(K(Ca)) can contribute to action potential repolarization and after-hyperpolarization in GH3 cells. In this study, we examined how the activation of I(K(Ca) at the cellular level could be functionally coupled to Ca2+ influx through L-type Ca2+ channels. A 30-msec Ca2+ influx step to 0 mV was found to exhibit substantial contribution of Ca2+ influx through the activation of I(Ca,L) to the activation of I(K(Ca)). A bell-shaped relationship between the conditioning potentials and the integrated I(K(Ca)) was observed, suggesting that the magnitude of integrated I(Ca,L) correlates well with that of integrated I(K(Ca)) in the same cell. A linear relationship of integrated I(Ca,L) and integrated I(K(Ca)) was found with a coupling ratio of 69+/-7. The value of the coupling ratio was unaffected by the presence of Bay K 8644 or nimodipine, although these compounds could effectively affect the amplitudes of both I(K(Ca)) and I(Ca,L). However, tetrandrine could decrease the coupling ratio. Paxilline or intracellular Ca2+ buffer with EGTA decreased the coupling ratio, while apamin had no effect on it. Interestingly, phorbol 12-myristate 13-acetate also reduced the coupling ratio significantly, whereas thapsigargin increased this value. Thus, the present study indicates that the activation of I(K(Ca)) during brief Ca2+ influx, which is inhibited by paxilline, is coupled to Ca2+ influx primarily through the L-type channels. The selective modulation of I(K(Ca)) by second messengers or Ca2+ release from internal stores may affect the coupling efficiency and hence cellular excitability.

Differential regulation of Ca2+ influx by fMLP and PAF in human neutrophils: possible involvement of store-operated Ca2+ channel

Calcium (Ca2+) influx into human polymorphonuclear cells (PMNs) in response to N-formyl-Met-Leu-Phe (fMLP) and platelet-activating factor (PAF) stimulation was studied. Whole blood was taken by venous puncture from healthy human volunteers. PMNs were isolated, diluted, and incubated with 2 microM fura-2 AM. The cytosolic free calcium concentration, [Ca2+]i, in human neutrophils was determined by microfluorometry. We found that the net area under the fMLP- or PAF-induced [Ca2+]i rise curve in Ca2+-free medium decreased to 75% or 30% of the area under the curve in Ca2+ medium. Treatment of PMNs with phorbol myristate acetate (PMA), a protein kinase C activator, completely abolished the intracellular Ca2+ level stimulated by PAF, but not the intracellular Ca2+ level stimulated by fMLP. Treatment of PMNs with PAF did not abolish the intracellular Ca2+ level elevation stimulated by fMLP. In addition, treatment of PMNs with fMLP did not abolish intracellular Ca2+ level elevation stimulated by PAF. Loperamide, a positive modulator for store-operated calcium (SOC) channels, elicited an increase in intracellular calcium after the activation of SOC channels stimulated by fMLP or PAF. After the addition of guanosine 3',5'-cyclic monophosphate, N2,2'-O-Dibutyryl-, sodium salt (db-cGMP), the initial increase of PAF- or fMLP-induced PMNs intracellular Ca2+ fluorescences was well preserved, but the slope and the peak height of fluorescence curves declined compared with the curves without db-cGMP. In conclusion, we found that PAF and fMLP regulate the Ca2+ influx of PMNs in different ways. Most of the PAF-induced [Ca2+]i rise resulted from Ca2+ influx, and most of the fMLP-induced [Ca2+]i elevation resulted from intracellular stores release. The initial mobilization of intracellular Ca2+ stores in PAF-stimulated signals is mediated by protein kinase C (PKC) phosphorylation, but not in fMLP-stimulated route. SOC channels are present and important in the fMLP- or PAF-induced PMNs Ca2+ influx. There was no apparent cross-regulation between PAF- and fMLP-stimulated intracellular Ca2+ influx.

Studies on the cardiovascular action of TPY-beta: an antihypertensive agent with antiplatelet activity

1-Pyrrolidinylmethyl-2-naphthol hydrochloride (TPY-beta) has been reported to have hypotensive and bradycardiac effects in anesthetized rats. Whether administration of atropine or bilateral vagotomy affects mean arterial pressure or heart rate was examined. The percentage difference in hypotensive and bradycardiac effect of TPY-beta (0.5 mg/kg) was 63 +/- 5% and 68 +/- 9%, respectively, in unpretreated rats compared to control levels. Atropine pretreatment (0.1 mg/kg, i.v.) significantly reduced the depressant effect of TPY-beta, although heart rate and mean arterial pressure remained 21 +/- 3% and 31 +/- 4%, respectively, as compared to control levels. Vagotomy decreased heart rate and mean arterial pressure response but moderate bradycardiac (13 +/- 2%) and hypotensive (10 +/- 3%) effects still remained as compared to control levels. Unilateral microinjection of 1, 3.3 and 10 nM TPY-beta into the nucleus tractus solitarri elicited a dose-dependent depressor (-10 +/- 2; -20 +/- 3; -25 +/- 3 mmHg) and bradycardiac activities (-20 +/- 4; -26 +/- 5; -55 +/- 10 beats/min). TPY-beta also relaxed the isolated rat aortic rings preconstracted with high extracellular K+ (80 mM) and Ca2+ (1.9 mM). The above findings suggest that the suppressive effects of TPY-beta may involve activation of vagus nerve and a direct inhibition of Ca2+ channel. In addition, TPY-beta inhibited the aggregation of washed rabbit platelets (aggregated by arachidonic acid and collagen) and adhesiveness on fibrinogen-coated surface. The results suggest that TPY-beta possesses antihypertensive and antiplatelet activity.

Inhibition of 2-P-mercaptophenyl-1,4-naphthoquinone on human platelet function

As widely assumed, platelets and coagulation system heavily influence the pathogenesis and progression of cardiovascular diseases. Some 1,4-naphthoquinone derivatives, such as vitamin K3, have been reported to increase the synthesis of coagulation proteins. In this study, we examine how 2-p-mercaptophenyl -1,4-naphthoquinone (NTP), a newly synthesized 1,4-naphthoquinone derivative, affects the platelet function in humans. A tapered parallel plate chamber which provided a range of shear stress covering the entire physiological range in human circulation is used to assess platelet adhesiveness on fibrinogen coated-surface. In addition, platelet aggregation and thromboxane B2 (TXB2) production by inducers are evaluated by the turbidimetric method and enzyme immunoassay kit, respectively. Moreover, platelets [Ca2+]i are measured using a dual-wavelength fluorescence spectrophotometer. Analysis results indicate that 1) NTP decreases the percentages of attached platelets at the locations in various shear stresses and the levels of platelet adhesiveness, denoted as the slope; 2) NTP can inhibit the platelet aggregation by ADP (2 microM) and collagen (25 microg/ml), and the IC50 are: 0.32 and 26.83 microg/ml, respectively; and 3) NTP markedly inhibits TXB2 formation and platelet [Ca2+]i elevation caused by ADP and collagen. Therefore, we conclude that NTP may inhibit platelet adhesiveness on fibrinogen coated-surface, aggregability, [Ca2+]i, and thromboxane production, and that it may be used as an antiplatelet agent.

Inhibition of Ca2+-activated K+ current by clotrimazole in rat anterior pituitary GH3 cells

The ionic mechanism of clotrimazole, an imidazole antimycotic P-450 inhibitor, was examined in rat anterior pituitary GH3 cells. In perforated-patch whole-cell recording experiments, clotrimazole reversibly caused an inhibition of the Ca2+-activated K+ current in a dose-dependent manner. The IC50 value of the clotrimazole-induced inhibition of I(K(Ca)) was 3 microM. In the outside-out configuration of single channel recording, application of clotrimazole (10 microM) into the bath medium did not change the single channel conductance of large conductance Ca2+-activated K+(BK(Ca)) channels, but it suppressed the channel activity significantly. The change in the kinetic behavior of BK(Ca) channels caused by clotrimazole in these cells is found to be due to a decrease in mean open time and an increase in mean closed time. Other structurally distinct P-450 inhibitors (e.g. ketoconazole or econazole) also effectively suppressed the amplitude of I(K(Ca)). Clotrimazole (10 microM) blocked both the inactivating and non-inactivating components of the voltage-dependent K+ outward current (I(K(V))), but it produced a slight reduction of L-type Ca2+ inward current (I(Ca,L)) without altering the current-voltage relationship of I(Ca,L). Clotrimazole (10 microM) also increased the firing rate of action potentials. These results provide direct evidence that clotrimazole is capable of suppressing the activity of BK(Ca) channel in GH3 cells. Because of the non-selective inhibitory effect of clotrimazole on I(K(Ca)) and I(K(V)), this inhibition is mainly, if not entirely, due to a direct channel blockade. Thus, the present study implies that the blockade of these ionic channels by clotrimazole would affect hormonal secretion and neuronal excitability.

Primary angioplasty for acute myocardial infarction resulting from the simultaneous occlusion of two major coronary arteries

Primary angioplasty for acute myocardial infarction is frequently performed. Not uncommonly, more than one occluded artery may be present. Usually only one is an acute event, the others being chronic occlusions. We encountered a patient who presented with two simultaneous occlusions; both were successfully recanalized. We discuss some observations that assisted us in devising our treatment strategy.

Synthesis and cytotoxicity evaluation of some 8-hydroxyquinoline derivatives

Interest in Mannich bases of 8-hydroxyquinoline stems from reports of their high potency against human cancer cells. In the search for potential anticancer drug candidates, Mannich bases of 8-hydroxyquinoline (7-pyrrolidinomethyl-8-hydroxyquinoline, 7-morpholinomethyl-8-hydroxyquinoline, 7-piperidinomethyl-8-hydroxyquinoline and 7-diethylaminomethyl-8-hydroxyquinoline) were synthesised by reaction with various secondary amines and formaldehyde. They were prepared as hydrochlorides. The cytotoxic activity of 7-pyrrolidinomethyl-8-hydroxyquinoline, 7-morpholinomethyl-8-hydroxyquinoline and 7-diethylaminomethyl-8-hydroxyquinoline compounds in the National Cancer Institute in-vitro cancer cell line panel was determined. It was found that they exhibited substantial cytotoxic activity against leukaemia. The log concentration of 7-pyrrolidinomethyl-8-hydroxyquinoline, 7-morpholinomethyl-8-hydroxyquinoline and 7-diethylaminomethyl-8-hydroxyquinoline that inhibited 50% of 60 cell lines' growth were -4.81 M, -5.09 M and -5.35 M, respectively. Compound 7-pyrrolidinomethyl-8-hydroxyquinoline was selected for further in-vivo testing. The electrophysiological effect of 7-pyrrolidinomethyl-8-hydroxyquinoline also was tested in human myeloma cells (RPMI 8226). The outward current was voltage dependent, activating at -40 mV and believed to be the voltage-activated K+ current I(K(V)). 7-Pyrrolidinomethyl-8-hydroxyquinoline (1-30 microM) caused the inhibition of I(K(V)) in a concentration-dependent manner. The IC50 value of 7-pyrrolidinomethyl-8-hydroxyquinoline-induced inhibition of I(K(V)) is 23 microM. The GI50 value of 7-pyrrolidinomethyl-8-hydroxyquinoline-induced inhibition of cell growth is 14 microM. The results suggest that at least part of the cytotoxicity effect of 7-pyrrolidinomethyl-8-hydroxyquinoline on myeloma cells could be related to blockade of voltage-activated K+ channels.

2-Hydroxymethyl-1-naphthol diacetate (TAC) suppresses the superoxide anion generation in rat neutrophils

We have investigated the inhibitory effect of 2-hydroxymethyl-1-naphthol diacetate (TAC) on the respiratory burst of rat neutrophils and the underlying mechanism of action was also assessed in this study. TAC caused concentration-related inhibition of the formylmethionyl-leucyl-phenylalanine (fMLP) plus dihydrocytochalasin B (CB)- and phorbol 12-myristate 13-acetate (PMA)-induced superoxide anion (O2*-) generation (IC50 10.2+/-2.3 and 14.1+/-2.4 microM, respectively) and O2 consumption (IC50 9.6+/-2.9 and 13.3+/-2.7 microM, respectively) of neutrophils. TAC did not scavenge the generated O2*- during dihydroxyfumaric acid autoxidation. TAC inhibited both the transient elevation of [Ca2+]i in the presence or absence of [Ca2+]o (IC50 75.9+/-8.9 and 84.7+/-7.9 microM, respectively) and the generation of inositol trisphosphate (IP3) (IC50 72.0+/-9.7 microM) in response to fMLP. Cytosolic phospholipase C (PLC) activity was also reduced by TAC at a same range of concentrations. The PMA-induced PKC-beta associated to membrane was attenuated by TAC (about 80% inhibition at 30 microM). Upon exposure to fMLP, the cellular cyclic AMP level was decreased in neutrophils pretreated with TAC. TAC attenuated fMLP-induced phosphorylation of mitogen-activated protein kinase (MAPK) p42/44 (IC50 17.4+/-1.7 microM), but not p38. The cellular formation of phosphatidic acid (PA) and, in the presence of ethanol, phosphatidylethanol (PEt) induced by fMLP was inhibited by TAC in a concentration-dependent manner (IC50 25.4+/-2.4 and 25.9+/-1.4 microM, respectively). TAC had no effect on the O2*- generation of PMA-stimulated and arachidonic acid (AA)-stimulated NADPH oxidase preparations. However, TAC caused concentration-related decrease of the membrane associated p47phoX in PMA-stimulated neutrophils (about 80% inhibition at 30 microM). We conclude that inhibition by TAC of the neutrophil respiratory burst is probably attributable to the blockade of the p42/44 MAPK and phospholipase D (PLD) pathways, the membrane translocation of PKC, and to the failure in assembly of a functional NADPH oxidase complex. Blockade of the PLC pathway by TAC probably plays a minor role.

A chelating agent possessing cytotoxicity and antimicrobial activity: 7-morpholinomethyl-8-hydroxyquinoline

7-Morpholinomethyl-8-hydroxyquinoline (MO-8HQ), which like 8-hydroxyquinoline (8HQ) readily forms a chelate, was synthesized and found to possess cytotoxicity and antimicrobial activity. Both 8HQ and MO-8HQ were cytotoxic to human carcinoma cell lines at micromolar concentrations. MO-8HQ also inhibited DNA synthesis of tumor cells at micromolar concentrations, suggesting that MO-8HQ might chelate metals necessary for the enzymatic catalysis of DNA biosynthesis. MO-8HQ was more active against gram positive bacteria than gram negative bacteria and its potency correlated with iron chelation. An "unsaturated" chelate with a MO-8HQ to Fe ratio of 2:1 exhibited greater antibacterial activity than MO-8HQ alone. Among the organisms tested, Micrococcus flavus was most susceptible with a MIC of 3.9 microg/ml. MO-8HQ also exhibited anti-fungal activity at 7-15 microg/ml. MO-8HQ:Fe chelate markedly increased the susceptibility of Escherichia coli to deoxycholate. Addition of Ca2+ or Mg2+ reversed the sensitivity of bacteria to deoxycholate as well as to rifampicin. It is suggested that MO-8HQ exerts its biological activity as a membrane-active agent through metal ion chelation.

Co-activation of nonselective cation channels by store depletion and oxidative stress in monocytic U937 cells

Two different types of nonselective cation currents in monocytic U937 cells were characterized with the aid of patch-clamp technique. When the cells were exposed to oxidative stress with 10 mM H2O2, a nonselective cation current (INS) can be elicited. This current was still observed when extracellular cations are Ca2+. The change in intracellular Cl- concentrations did not shift the reversal potential of this current. This current showed no any rectification, and was time- and voltage-independent at any potentials. The further addition of LaCl3 (100 microM) or dithiothreitol (10 microM) effectively suppressed this current. However, SK & F 96365 (100 microM) or nifedipine (10 microM) did not produce any effect on it significantly. On the other hand, depletion of Ca2+ stores by different maneuvers, such as the application of ATP, thapsigargin or A23187, or dialysis of the cells with inositol-1,4,5-trisphosphate activated another type of nonselective current which was identified as store-operated Ca(2+)-permeable current (ISOC). Unlike H2O2-induced INS, this current was observed to slowly inactivate when the voltage steps were hyperpolarized. Current-voltage relation of this current showed inward rectification. When the cell was challenged with both store depletion and H2O2, INS on the top of ISOC can be activated. These results suggest that different types of nonselective cation channels can be co-expressed in the same cell. Therefore, in U937 cells nonselective cation currents can be activated after the stimulation with oxidative stress, store depletion or both. The activation of these nonselective cation channels may affect intracellular Ca2+ homeostasis.

Predictors of survival after coronary bypass grafting in patients with total occlusion of the left main coronary artery

Twenty-three patients with angiographically documented total occlusion of the left main coronary artery were retrospectively identified. Statistical analysis suggests that poor right-to-left collaterals and the presence of concurrent significant right coronary artery disease were weakly associated with decreased survival after bypass surgery.

Studies on the hypotensive and bradycardic effects of 1-piperidinylmethyl-2-naphthol hydrochloride

The cardiovascular activity of TPI in lowering the blood pressure and heart rate in anesthetized rats was studied using pharmacological and physiological techniques. The hypotensive and bradycardiac actions induced by a bolus intravenous injection were significantly inhibited by pretreatment with atropine (0.1 mg/kg; i.v.). Vagotomy almost abolished the hypotensive response but moderate bradycardia still remained. Microinjection of TPI (1-10 nmol) into the nucleus tractus solitarii of brain stem produced a prominent dose related hypotensive and bradycardic effects. TPI also produced a decrease in the force of contraction of the isolated right atrium of guinea pig. These results suggest that the effects of TPI may involve an activation of the vagus nerve and suppressive action on myocardial tissue.

Cytotoxicity and antimicrobial activity of some naphthol derivatives

2-Hydroxymethyl-1-naphthol diacetate (TAC) and sixteen Mannich base derivatives of naphthol were prepared and examined for cytotoxicity and antimicrobial activity. Cytotoxicity was examined against four human carcinoma cell lines. Several derivatives were effective at concentrations < 4 micrograms/ml. TAC showed the highest cytotoxicity. Inhibition of DNA-, RNA-, and protein synthesis by TAC was also studied and discussed. TAC also exhibits potent antimicrobial activity against Enterobacter clocae 23355, Klebsiella pneumonia 13883, Proteus vulgaris 13315, Pseudomonas aeruginosa 27853, Candida parapsilosis, Candida tropicalis, Trichosposon beigelli, and Rhodotorul spp. with minimum inhibitory concentrations of 0.1-0.4 microM. These results indicate that esterification by Bruson reaction of 1-naphthol Mannich base to TAC enhances the cytotoxicity and antimicrobial activity.

Synthesis and biological evaluation of some potential antimalarials

Malaria chemotherapy has been well reviewed. Malarial parasites gaining resistance is the major problem in the treatment of the disease. Some strains are resistant not only to chloroquine but also to amodiaquine. Few new drugs are available or foreseen for the near future. The principal metabolite of cinchona alkaloids appears to be oxidized at C-2. This may result in a loss of activity. Pinder and Burger suggested that a trifluoromethyl group will prevent this oxidation. So 2-tribromomethyl-6-methoxy-4-(4-hydroxy-3-pyrrolidinomethylanil ino)quinoline (1) was synthesized as a potential biocide (Scheme 1).

Guaiacoxypropanolamine derivatives of capsaicin: a new family of beta-adrenoceptor blockers with intrinsic cardiotonic properties

A series of guaiacoxypropanolamine derivatives of capsaicin was synthesized by replacing the phenolic OH of N-nonanoylvanillamide with epichlorohydrin, followed by cleavaging the obtained epoxide compound with alkylamines. Intravenous injection of these propanolamine derivatives (1 mg/kg) in normotensive Wistar rats induced a transient fall in blood pressure but significantly reduced the heart rate for more than 30 min. These derivatives (10(-8)-10(-6) M) inhibited isoproterenol (10(-10)-10(-5) M)-induced positive chronotropic and inotropic effects in isolated guinea pig atrium. On the other hand, these derivatives (10(-5)-10(-4) M) exhibited a positive cardiotonic effect that is independent of intrinsic sympathomimetic effects. Investigation of the structure-activity relationship of these derivatives revealed that the position of the oxypropanolamine side chain and substituents of the 4-OH position play significant roles in imparting their pharmacological effects. Of the derivatives tested, the most effective one was compound 9. In conclusion, the results obtained from in vitro and in vivo studies suggested that these derivatives and compound 9 may be expected to be beta-adreneoceptor blocking agents with nonadrenergic positive chronotropic and inotropic properties.