Bioactivity and molecular docking studies of selected plant compounds

BACKGROUND

The shortcomings of synthetic pesticides are becoming increasingly evident. In the pursuit of looking for alternative, environmentally friendly pesticides, the potential use of two naturally occurring sesquiterpenes, α-bisabolol and bisabolol oxide A, as bactericides or acaricides, was investigated against three gram-positive and three gram-negative bacteria, and the eggs and larvae of the cattle tick Hyalomma scupense, respectively. The primary targeted site of synthetic insecticides is acetylcholinesterase (AChE), so the inhibitory activity of both sesquiterpenes was evaluated. Then, molecular docking and molecular mechanics generalized Born surface area (MM-GBSA) studies were performed to gain insight into their binding mode in the AChE active site.

RESULTS

Bisabolol oxide A showed good activity against Staphylococcus aureus, Escherichia coli, and Salmonella enteritidis with inhibition zones ranging from 16 to 34 mm and minimal inhibitory concentration (CIM) of 3.125  mg mL-1. Ovicidal and larvicidal assays revealed promising activity of α-bisabolol and bisabolol oxide A against H. scupense, with bisabolol oxide A being more effective against larval ticks with lethal concentration (LC50) value of 0.78%. Both compounds also displayed potent anti-AChE activity with inhibition concentration (IC50) values of 37.09 and 28.14 μg mL-1, respectively. Furthermore, α-bisabolol and bisabolol oxide A exhibited good and comparable docking scores (-7.289 and -7.139 Kcal mol-1, respectively) and were found to accommodate in the active-site gorge of AChE via hydrogen bonding and hydrophobic interactions.

CONCLUSION

Bisabolol oxide A and, to a lesser degree, α-bisabolol are active against bacteria and ectoparasites and may represent an economical and sustainable alternative to toxic synthetic pesticides to control pathogens. © 2024 Society of Chemical Industry.

Laboratory assessment of the acaricidal, repellent and anti-cholinesterase effects of Melaleuca alternifolia and Chamaemelum nobile essential oils against Hyalomma scupense ticks

In cattle, Hyalomma scupense serves as an important vector of several pathogens resulting in diseases, subsequently affecting the agricultural field as well as the economy. Resistance to chemical acaricides has become widespread affirming the need for new drugs to tick control. The goal of this study was to investigate the acaricidal, repellent activities as well as the putative mode of action of two essential oils (EOs) from Melaleuca alternifolia (Tea tree) and Chamaemelum nobile (Roman chamomile) on Hyalomma scupense. The chemical composition of EOs was also evaluated. Different concentrations of EOs were tested in vitro for their acaricidal property on adults and larvae of H. scupense using adult immersion test (AIT) and larval packet test (LPT). Additionally, using Ellman's spectrophotometric method, the anticholinesterase (AChE) inhibition activity of M. alternifolia and C. nobile EOs was assessed in order to understand their putative mode of action. The main compounds of C. nobile were α-Bisabolene (22.20%) and (E)-β-Famesene (20.41%). The major components in the analyzed M. alternifolia were Terpinen-4-ol (36.32%) and γ-Terpinene (13.69%). Adulticidal and larvicidal assays demonstrated a promising efficacy of the essential oils against tick H. scupense. The lethal concentration (LC50) values obtained for M. alternifolia and C. nobile oils were 0.84 and 0.96 mg/mL in the AIT and 0.37 and 0.48 mg/mL in the LPT, respectively. Regarding repellent activity, M. alternifolia achieved 100% repellency at the concentration of 1 mg/mL while C. nobile showed 95.98% repellency activity at concentration of 4 mg/mL. Also, M. alternifolia and C. nobile EOs displayed potent AChE inhibition with IC50 value of 91.27 and 100.12 μg/mL, respectively. In the present study, M. alternifolia and, to a lesser degree, C. nobile EOs were found to be effective in vitro acaricides, repellents and acetylcholinesterase inhibitor against H. scupense ticks. These plants may represent an economical and sustainable alternative to toxic synthetic acaricides in the management of ectoparasites of veterinary importance.

Pistacia lentiscus essential oil and its pure active components as acaricides to control Dermanyssus gallinae (Acari: Mesostigmata)

The goal of this work was to assess the in vitro acaricidal effects of Pistacia lentiscus essential oil and its pure active components against red poultry mites Dermanyssus gallinae as an alternative to chemical acaricide (formamidines). Essential oil was obtained using hydrodistillation and then analyzed using GC-MS. The following major components were identified: α-pinene (20.58 %), D-Limonene (18.16 %), β-Myrcène (15.06 %), 4-Terpineol (7.68 %), caryophyllene (5.45 %) and γ-terpinene (5.21 %). The toxicity of essential oil and its six monoterpenes were tested at concentrations ranging from 0.43 to 3.50 mg/cm2, using contact and spraying bioassays. Toxicity was expressed as a lethal concentration (LC50 or LC90). The experiment results revealed that activity was method and concentration dependent, and the spraying method was more effective than the contact bioassay for acaricidal activity. In this bioassay, the highest mortality was observed with 4-Terpineol. The LC50 was estimated to be 0.184 mg/cm2 for this substance, followed by α-pinene, the LC50 of which was estimated to be 0.203 mg/cm2. Caryophyllene and γ-terpinene were found less effective in controlling D. gallinae. P. lentiscus oil and its major compounds were also evaluated for anti-acetylcholinesterase (AChE) effects; 4-Terpineol was found to be the most effective AChE inhibitor with IC50 values reaching 18.73 ± 2.83 µg/mL. This framework pointed out the importance of the traditional use of P. lentiscus as an ecofriendly alternative against ectoparasite of veterinary importance; D. gallinae. In vivo trials should also be conducted to assure the safe use of essential oils or individual compounds and to achieve efficient acaricidal property.

Toxicity, repellency, and anti-cholinesterase activities of bioactive molecules from clove buds Syzygium aromaticum L. as an ecological alternative in the search for control Hyalomma scupense (Acari: Ixodidae)

Introduction

The goal of the current study is to evaluate the acaricidal and repellent properties of the ethanolic extract, essential oil, and primary component eugenol from Syzygium aromaticum against Hyalomma scupense cattle ticks. Their potential mechanisms of action were also examined, using an in vitro assay.

Methods

Clove essential oil was extracted using hydrodistillation technique. Gas chromatography-mass spectrometry (GC-MS) was performed to identify the chemical composition of clove. To evaluate the adulticidal, ovicidal, larvicidal and repellent proprieties of clove essential oil, eugenol and ethanolic extract on H. scupense, in vitro assays were performed using the adult immersion test (AIT), the ovicidal test, the larval packet test (LPT), the filter paper test and anti-acetylcholinesterase (AChE) activity.

Results

After treatment, eugenol, the primary phytoconstituent of clove oil, which accounts for 97.66% of the whole oil, had 99.22% acaricide activity and inhibited egg hatching at a concentration of 10 mg/mL. Eugenol and clove essential oil showed potent adulticidal effect at high concentrations (10 mg/mL), achieving 100 and 93.76% mortality, respectively. The ethanolic extract exhibited moderate activity. At high concentration, the larvicidal activity of S. aromaticum oil, eugenol, and ethanolic extract were 100, 100, and 77.18%, respectively. In filter paper experiments, when tested at the concentration 5 mg/mL; eugenol showed the longest repellent effect up to 6 h. We also found that eugenol was the most active AChE inhibitor (IC50 = 0.178 mg/mL). Nevertheless, additional investigations are required to confirm the accurate mechanism and the relevance of clove in practical application.

Conclusion

Overall, our research indicated that, because its effectiveness as acaricide, S. aromaticum essential oil and its phytoconstituent eugenol may offer an alternative source for the control of H. scupense cattle ticks.

Enhanced textile dye removal from wastewater using natural biosorbent and Shewanella algae B29: Application of Box Behnken design and genomic approach

In this study, Box-Behnken design combining seven factors at three levels were used to optimize the elimination of CI Reactive Red 66 in artificial seawater, by the combination of eco-friendly bio-sorbents and acclimated halotolerant microbial strain. Results showed that macro-algae and cuttlebone (2 %) were the best natural bio-sorbent. Additionally, the selected halotolerant strain able to rapidly remove dye was identified as Shewanella algae B29. The optimization process revealed that decolourization of CI Reactive Red 66 yields reached 91.04 % under the following variable values: dyes concentration (100 mg/l), salinity (30 g/l), peptone (2 %), pH (5), algae C (3 %), cuttlebone (1.5 %) and agitation (150 rpm). The whole genome analysis of S. algae B29 demonstrated the presence of several genes coding for valuable enzymes involved in textile dyes biotransformation, adaptation to stress as well as biofilm formation implying its potential use in biological textile wastewater treatment.

Acaricidal and anthelmintic efficacy of Ocimum basilicum essential oil and its major constituents estragole and linalool, with insights on acetylcholinesterase inhibition

The present study evaluated the acaricidal and anthelmintic action of Ocimum basilicum essential oil and its main components against ticks and helminth parasites as well as to relate these activities to acetylcholinesterase inhibition. The in vitro acaricidal activity against Hyalomma scupense was evaluated by Adult Immersion Test (AIT) and Larval Packet Test (LPT), while the in vivo nematocidal potential was assessed in laboratory mice infected with Heligmosomoides polygyrus using fecal egg count reduction (FECR) and total worm count reduction (TWCR). Chemical analyzes were performed by gas chromatography coupled to mass spectrometry (GC-MS). Estragole (80.87%) and linalool (16.12%) were the major compounds detected in O. basilicum essential oil. In the AIT assay for H. scupense tick, LC₅₀ of estragole, O. basilicum oil and linalool were 0.73, 0.81 and 0.97 mg/mL, respectively. In LPT, estragole, linalool and essential oil showed LC₅₀ of 0.22, 1.11 and 1.19 mg/mL, respectively. Against He. polygyrus, the highest activity was observed with estragole administered at 100 mg/kg body weight (bwt), which resulted in a FECR of 90.86% and a TWCR of 82.91%. The O. basilicum essential oil, estragole and linalool inhibited the enzyme acetylcholinesterase (AChE) extracted from both parasites species. Estragole was found the most active AChE inhibitor with IC₅₀ of 0.176 mg/mL for H. scupense and IC₅₀ of 0.138 mg/mL for He. polygyrus larvae. The results of the present study pointed out the importance of the traditional use of O. basilicum as an eco-friendly alternative against endo and ectoparasites. In vivo trials should also be conducted to confirm the above-mentioned activities and to assure the safe use of natural plants.

Factors associated with changes in sexual behavior during Ramadan

Introduction

Previous studies have shown that the month of Ramadan has a negative impact on the sexual life of fasters. Sexuality during Ramadan seems monotonous, rather poor, leaving little room for foreplay, sensuality and diversification of the sexual repertoire.

Objectives

To examine the socio-demographic and religious factors associated with the change in the sexual lives of fasters

Methods

A cross-sectional study was conducted among married Muslim volunteers in Tunisia. The data was collected with an anonymous self-completed questionnaire, one week before Ramadan (W-1) and the fourth week of Ramadan (W4).

Results

We included 100 participants in this survey.The analytical study found a negative correlation between age and the frequency of coitus during Ramadan (r= -0.2, p= 0.04). The lenth of the marriage was associated with less communication about sexual satisfaction during Ramadan (P=0.01). Rural origin was associated with less tenderness (p=0.03) and shorter foreplay (p=0.03). Wearing the veil was associated with sexual abstinence in women during Ramadan (p=0.038) and not wearing it was associated with the cessation of oral sex (p=0.04). The practice of prayer was correlated to a lesser diversification of sexual positions (p=0.01) and to the withdrawal of certain sexual positions: posterior vaginal (p=0.01), lateral (p=0.02), Andromache (p=0.004).

Conclusions

Changes in the expression of sexuality during Ramadan are not consistent with religious dictates. These findings suggest that the perception of sexuality and its practices are motivated by tradition and culture much more than religion.

Disclosure

No significant relationships.

Tunisian’s largest Psychiatric emergency department in the context of the COVID-19 lockdown

Introduction

General Lockdown was first declared in Tunisia from March 20th to May 4th 2020 to contain the spread of COVID19 pandemic, the last sanitary lockdown period was declared from July 12th to august 1st in 2021. Psychiatric emergency access and consultation has been affected by the confinement. RAZI Hospital Emergency Department (RHED) is the only emergency department in Tunisia specialized in psychiatry. Thus making it the most representative psychiatric emergency health care service in Tunisia.

Objectives

To assess changes in patients flow and admission rates in RHED in the context of the COVID-19 lockdown

Methods

We examined emergency room records and the hospital’s computer admission database during the first and the last COVID19 lockdowns and compared it to the same period of the previous year.

Results

The number of consultations was significantly lower in 2020 lockdown (N = 577) compared the same period in 2019 (N = 1525) (p<10−3). We observed a drop in RHED emergency hospitalization rate from 45.57% to 29.81% during this study period. The number of consultations per day was significantly lower during the first lockdown (N= 12.44) compared to the last lockdown (N=26.61) (p<10−3), the hospitalization rate rose from 29.81% during the first lockdown to 44.36% during the last.

Conclusions

Fear of COVID19 contamination and lockdown limitation had a huge impact on RHED visits and admissions. Medical team had to adjust in order to prevent further delay in acute psychiatric care.

Disclosure

No significant relationships.

The sexual function of women with epilepsy: a comparative study

Introduction

Epilepsy is a neurological disease that interferes negatively with many areas of the patient’s life. Sexual dysfunction is a frequent comorbidity in epileptic patients. Quality of life is particularly affected in women, who are also culturally stigmatized because of their illness.

Objectives

To assess the sexual function of women with epilepsy compared to healthy women.

Methods

This was a case-control study of female patients with generalized epilepsy, carried out at the national institute of neurology in Tunisia in 2018. The controls were the patients’ companions in the department. They were matched by age with the cases. Sexual function was assessed by the female sexual function index (FSFI).

Results

We included 40 cases and 40 controls.Their averge age was 30.45years. In comparison to the controls,the women with epilepsy had less kids ( p=0.04) and more miscarriages (p=0.032). On the other hand, women with epilepsy presented more sexual dysfunctions (p=0. 03) and had a lower total score on the FSFI (p=0.015) as well as significantly lower scores in the domains “desire” (p=0.009), “orgasm” (p=0.026), “satisfaction” (p=0.001) and pain (p=0.015).

Conclusions

The findings of this study are consisting with the literature, the women with epilepsy in this survey had impaired sexual function. More attention should be paid to these sexual disorders, previously considered secondary or even neglected.

Disclosure

No significant relationships.

Sexuality in the Muslim community during Ramadan

Introduction

Ramadan is a holly month for Muslims. Able-bodied adults fast and abstain from sexual activities from dawn to sunset. These hasty lifestyle changes have a major impact on the sexual life of the Muslim community.

Objectives

To assess the impact of Ramadan on sexual activity in a Tunisian community.

Methods

A cross-sectional study was conducted among married Muslim volunteers in Tunisia. The data was collected with an anonymous self-completed questionnaire, one week before Ramadan (W-1) and the fourth week of Ramadan (W4).

Results

We included 100 person in this study. The sample consisted of 59 females and 41 males. The average age was 40.3 years. During Ramadan, sexual intercourse happened more often on weekends (p=0.009) and mostly during the second part of the night (p ˂0.001). Data suggest a disturbed sex life with less satisfaction about sexual life compared to W-1 (p<0.05). Monthly sexual intercourse frequency dropped from 5.76 coitus/month on W-1 to 3.27 on W 4 (p<0.05) and Duration of sex from 9.45 minutes to 6.85 minutes (p˂0.001). Couples communicated less about sex (p=0.004). Sexual abstinence was more frequent (p=0.016). Preliminaries were less performed (P=0.01) and were shorter (p˂0.001).Oral sex was less frequent as well as some sexual positions: fellatio (p=0.01) and cunnilingus (p=0.002), sexual positions of Andromache (P=0.002), posterior vaginal (P˂0.001) and lateral (P=0.001). The participants used less pornography (p=0.007).

Conclusions

This study demonstrated the deleterious impact of the lifestyles changes in Ramadan on the sexual life. Better sexual and religious education is recommended to prevent sexual dysfunctions.

Disclosure

No significant relationships.

Synthesis, antibacterial, antibiofilm evaluation and molecular docking studies of 3-methyl- 2-propyl-2H-[1,2,4]triazolo[4,3b] [1,2,4,6]thiatriazine-1,1-dioxide

ABSTRACT. In the current study, a simple method for the synthesis of 3-methyl-2-propyl-2H-[1,2,4]triazolo[4,3b][1,2,4,6]thiatriazine-1,1-dioxide (2) was carried out. In the presence of pyridine, a reaction between amidine (1) and sulfuryl chloride occurs. FTIR spectroscopy, 1H and 13C NMR, mass spectra, and elemental analysis were utilized in order to verify the structure of a novel synthetic molecule. The antibacterial activities of compound (2) were tested against eight pathogenic bacteria and the minimum inhibitory concentration as well as minimum bactericidal concentration were determined. Moreover, the possible antibiofilm effect of compound (2) was evaluated. Molecular docking was investigated to determine the interaction between compound (2) and eight crystal structures of bacterial and yeast proteins associated with virulence activity and antimicrobial resistance. Our results showed that the new 3-methyl-2-propyl-2H-[1,2,4]triazolo[4,3b][1,2,4,6]thiatriazine-1,1-dioxide (2) compound has a moderate antibacterial activity toward the selected pathogenic bacteria. The obtained MICs varied from 32 to 512 µg/mL being the lowest values attributed to Staphylococcus epidermidis ATCC 14990 and Streptococcus mutans ATCC 25175 (MIC = 32 µg/mL).We noted also that heterocyclic compound (2) may inhibit bacterial biofilm formation at concentration depend manner with a lowest value obtained against S.mutans ATCC 25175 (BIC50 = 490 µg/mL). Molecular docking showed a promising inhibitory activity of compound (2) on TetM-mediated tetracycline resistance (3J25) and Staphylococcus aureus gyrase (3G7B) with lower binding energy compared to the other target proteins.                 KEY WORDS: Synthesis, Thiatriazine-1,1-dioxide, Antibacterial, Antibiofilm, Molecular docking Bull. Chem. Soc. Ethiop. 2022, 36(1), 109-117.                                                             DOI: https://dx.doi.org/10.4314/bcse.v36i1.10                                                       

Novel 6-aryl-7-alkyl/aryl-[1,2,4]triazolo[4,3-a][1,3,5]triazine-5(6H)-thiones, processes for their preparation, characterization and evaluation of their in vitro antioxidant activity

ABSTRACT. A series of nine new 6-aryl-7-alkyl/aryl-[1,2,4]triazolo[4,3-a][1,3,5]triazine-5(6H)-thiones (2a-i) were synthesized by a reaction of N-triazol-3-yl imidates (1) with three different isothiocyanate derivatives (RNCS)  in refluxing toluene. The structures of the final heterocyclic compounds were confirmed by 1H-NMR, 13C-NMR, FT-IR, elemental analysis, and mass spectral analysis. The target compounds (2a-i) were in vitro screened for their activity as antioxidants using DPPH (2,2′-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing/antioxidant power) methods. The results revealed that some triazolotriazine-5-(6H)thiones exhibited antioxidant activity ranging from moderate to high. The obtained findings revealed that the triazolotriazine-5-(6H)thiones (2g, 2h, and 2i) have superiority among all compounds, It is obvious that the presence of a hydroxyl group in the structure is essential for the antioxidant properties and should be taken into consideration in further design of structures with potential antioxidant properties.                     KEY WORDS: Imidates, Isothiocyanates, Antioxidant, Triazole, DPPH, FRAP   Bull. Chem. Soc. Ethiop. 2021, 35(3), 565-572. DOI: https://dx.doi.org/10.4314/bcse.v35i3.8

Efficacy of synergistic activity of seed oils from Carthamus tinctorius (Safflower) and Nasturtium officinale (Watercress) on lethality of the cattle tick Hyalomma scupense (Acari: Ixodidae)

Background:

Ticks and tick-borne diseases are a severe economic and public-health problem for cattle producers. The emergence of acaricide resistance to synthetic chemical treatments has prompted interest in developing alternative tick control methods.

Aim:

The main objective of the current research was to identify the chemical structure of Carthamus tinctorius and Nasturtium officinale seed oils and to assess their anti-tick properties against Hyalomma scupense ticks both alone and in combination (1:1).

Methods:

Analytical methods were used to analyze the chemical components. For in vitro assays, adults of H. scupense were immersed in C. tinctorius and N. officinale seed oils at 100, 125, 200, and 300 mg/ml concentrations; for 5 minutes. Larvae of H. scupense were dipped in 25, 50, 100, 125, 200, and 300 mg/ml doses of seed oils; the mortality percentage was determined after 24 hours.

Results:

The seed oil safflower was mainly composed of linoleic acid (84.48%), followed by palmitic acid (6.54%) and stearic acid (3.77%). Meanwhile, watercress seed oil was mainly composed of linolenic acid (50.78%), gondoic acid (13.57%), linoleic acid (10.58%), palmitic acid (8.02%), and erucidic acid (6.62%). The Adults Immersion Test showed the sensitivity of ticks to C. tinctorius and N. officinale seed oil: C. tinctorius seed oil caused (95%) mortality of H. scupense at 300 mg/ml, while N. officinale seed oil induced (88.68%) mortality at the same concentration. At a 200 mg/ml concentration, C. tinctorius and N. officinale oil combined caused 100% mortality. Tested oils showed larvicidal efficacy. LC50 values for C. tinctorius and N. officinale seed oils were 84.16 and 61.78 mg/ml, respectively, in 24 hours. LC50 value of oils association (50% C. tinctorius: 50% N. officinale) was 47.96 mg/ml.

The mixture of seed oils from two plants tested against H. scupense larvae and adult females at a 1:1 ratio showed synergistic interaction.

Conclusion:

Seed oils tested alone, and the mixture could be used as an alternative solution in the fight against ticks.

Fournier's gangrene: Seven years of experience in the emergencies service of visceral surgery at Ibn Rochd University Hospital Center

Introduction

This work aims to describe and discuss the epidemiological, clinical, therapeutic and evolution of Fournier's gangrene.

Materials and methods

Case series with retrospective data collection of patients treated for Fournier's gangrene between January 2010 and March 2017. The main etiologies, risk factors, postoperative complications outcomes and long term follow up results were analyzed.

Results

Eight four (84) patients were recruited. The average age of our patients was 49 years (with limits of 20–76), the male gender dominates our series (83.33%) with a sex ratio of 5 M/1W, the most frequently found risk factor was diabetes mellitus (37%). The most common etiology was anal abscesses (32%). The average time to consultation was 8 days (limits ranges from 3 to 30 days). All patients were admitted at a necrosis stage (100%). Anemia was identified in 85% of cases. The low platelets were noticed in 44.03% of cases. Hypoalbuminemia was found in 93% of cases. All patients (100%) benefited resuscitation initially and antibiotic therapy on their admission. They received emergency surgical debridement with a cleansing stoma. The average length of hospital stay was 13 days and complications occurred in 33% of cases. The mortality rate was 7.14%.

Conclusion

Fournier's gangrene is a medico-surgical emergency with a high morbidity and mortality rate. Early diagnosis as well as antibiotic therapy and the quality of debridement save the patients.

•

Fournier's gangrene is a rare but severe disease.

•

The diagnosis and treatment delay and lesions extension increase mortality.

•

The treatment is multidisciplinary.

•

Early diagnosis and treatment improve prognosis.

•

Tobacco intoxication is suspected to be risk factor.

Surgical management of recto-vaginal fistula (about 6 cases)

Introduction

Recto-vaginal fistula (RVF) is defined as a pathological epithelialized communication between the posterior wall of the vagina and the anterior wall of the rectum through the recto-vaginal septum. RVFs are rare and represent less than 5% of rectal fistulas. Occurring after childbirth or during a proctological pathology, they create a deep distress for the patients. The aim of our work is to analyze the epidemiological particularities and the risk factors of occurrence of RVF as well as the modalities and results of our therapeutic management.

Materials and methods

Our work is retrospective analytic and comparative concerning 6 cases operated in the department of general surgery 3 of the UHC Ibn Rochd of Casablanca for recto vaginal fistula or recidive over a period of 7 years from 2012 to 2018.

Results

The analysis of the results of our study allowed us to note: A frequency of occurrence of RVF of about 0.48%. The average age at diagnosis was 55 in our patients. The etiologies were dominated by post-radiation (33.33%) and post-operative (16.66%) RVFs. The predominant mode of delivery in our study was vaginal delivery (83.33%). The antecedents were dominated by pelvic irradiation in 50% of patients, and pelvic surgery for cervical cancer and/or rectal cancer (50%). The diagnosis was revealed by a vaginal stool output in all patients. Surgical treatment was performed in all our patients. The surgical technique of choice in our series was drainage by Stenon, in 83.33% of patients. A protective stoma was performed in all our patients studied, a colostomy in 66.66%, and an ileostomy in 33.33% of patients. The immediate postoperative evolution was excellent in all our patients, while the short- and medium-term evolution revealed the occurrence of recurrence in one third of the patients (33.33%). The treatment of choice for recurrence was the interposition of a pedicled fat flap of the labia majora, known as the modified Martius technique. The morbidity, represented mainly by recurrence, was 25%, with a mortality rate of 0%.

Discussion

The occurrence of RVF in all its etiologies seems to be infrequent. However, its real incidence remains poorly documented in the literature, it varies between 0.3% and 15.3%. RVFs are considered simple or complex depending on their size, location and etiology. The high or low location and the etiology of the RVF determine the choice of the approach during surgical management. The diagnosis is most often clinical. The examination will try to find the cause of the RVF and the associated lesions. RVF can be asymptomatic. The importance of the symptoms depends on the topography of the fistula, the diameter of the orifice, and the quality of the intestinal transit. No additional investigations are required to confirm the diagnosis of RVF, since the positive diagnosis is essentially clinical. However, in the case of a high or complex fistula, the clinician can support his or her pre-therapeutic assessment with the exploration of imaging data, especially those of the digestive opacification, MRI and pelvic CT. The causes of RVFs are multiple. However, their proportions are difficult to establish. Post-obstetrical RVFs, those due to Crohn's disease, and post-op are probably the most frequent. The literature describes a variety of surgical approaches and treatment options for RVF. However, there are no treatment recommendations. The available data are vague and do not define an optimal treatment. Medical treatment with antibiotics and sitz baths is often necessary to control the local infection. The surgical management of RVFs is complex and follows several principles. The therapeutic arsenal is very varied and constitutes a real “escalation”, ranging from simple drainage by suture to the radical treatment represented by abdominal-pelvic amputation. The results of the treatment of simple VF are excellent in all studies. The healing rate varies from 75 to 100% depending on the authors.

Conclusion

The results of this study confirm the low incidence of RVF, and show that vaginal delivery and a history of pelvic surgery (for rectal or cervical cancer) are the most frequent predictors of RVF. Thus, from a therapeutic point of view, medical treatment is always required, it allows the flow of the fistula to be reduced, which facilitates preparation for the surgical procedure.

•

RVFs are rare and represent less than 5% of rectal fistulas

•

The aim of our work is to analyze the epidemiological particularities and the risk factors of occurrence of RVF as well as the modalities and results of our therapeutic management.

•

The surgical management of RVFs is complex

The impact of confinement on anxiety rates of the entourage of patients in the psychiatric hospital of Tunis

Introduction

The confinement did begot a recrudescence in the rate of stress within populations. Meanwhile, research targeting the mental health of the psychiatric patients’ accompanyings are scarce.

Objectives

Detect and evaluate anxiety levels of patients’ entourage during confinement.

Methods

It is a retrospective, descriptive and analytical study based on a random sample of People accompanying psychiatric patients from externals consultations service in the only Psychiatric Hospital in Tunisia. Data were been collected during the month of June 2020 via a 20 items questionnaire and a score HAD issued in Arabic.

Results

One hundred thirty five accompanyings were surveyed. The age group was predominantly between 51 and 60 with a sex ratio of 0.31. Near half was the parents. eighty seven were unemployed, 38 stopped working due to confinement and 10 have been worked normally. A pathological anxiety HAD score (>7) was found in 36 accompanyings (26, 67 %). Amongst them, 19 had manifested symptoms. Anxiety levels are significantly much higher in accompanyings of patients with personality disorders (p=0.053). Otherwise, 52, 6% of accompanyings who stopped working felt more under pressure than before lockdown. In contrary to those who did not worked before at all (29.9 %) and those who continued working (10%).

Conclusions

It seems that the entourage of mentally ill patients experience a continuous psychological distress, which was uncovered and marked in confinement period. Thus, it is necessary to establish screening programs, psychological education and early care to ensure their well-being.

Disclosure

No significant relationships.

In vitro acaricidal activity of essential oil and crude extracts of Laurus nobilis, (Lauraceae) grown in Tunisia, against arthropod ectoparasites of livestock and poultry: Hyalomma scupense and Dermanyssus gallinae

The current study assayed the toxicity of Laurus nobilis essential oil and crude extracts obtained using solvents of increasing polarity (cyclohexane, acetone and ethanol), on two ectoparasites of veterinary importance, i.e., Hyalomma scupense and Dermanyssus gallinae. The major components detected in bay laurel essential oil were dominated by 1.8-cineole (46.56 %), α-terpinenyl acetate (13.99 %), sabinene (7.69), α-pinene (5.75), linalool (5.50), methyleugenol (5.36 %) and β-pinene (3.97). The highest total phenolic and flavonoids contents were present in the ethalonic extract of L. nobilis leaves at an amount of 152.88 mg gallic acid equivalents per gram of dry weight (GAE/g DW) and 21.77 mg quercetin equivalent per gram of dry weight (QE/g DW), respectively. In vitro acaricidal effects of essensial oil and crude extract of L. nobilis against H. scupense were ascertained by adult immersion test of engorged females (AIT) and larval packet test (LPT) compared with a reference drug amitraz. The essential oil exhibited strong acaricidal activity against tick engorged female and inhibition of hatching eggs. After 24 h of exposure, at the highest tested concentration (100 mg/mL) essential oil induced 90.67 % mortality of H. scupense larvae (LC₅₀ = 10.69 mg/mL). Otherwise, essential oil exhibited high acaricidal activity compared to extracts, and among the extract, the ethanolic extract revealed the highest acaricidal efficacy (81.27 % female mortality). Results from mite contact toxicity showed that essential oil and extracts from L. nobilis were toxic to D. gallinae. Bay essential oil was both more toxic to mites, and faster in exerting this toxicity than other tested crude extracts. L. nobilis essential oil concentration leaded to enhance mortality of D. gallinae reaching the highest (100 %) mortality at 12 h with a concentration of 320 mg/mL. While, ethanolic extract acheived this rate after 24 h of exposure at same concentration. Cyclohexanic extract showed weak acaricidal activity.

Tokophobia or post-traumatic stress disorder ? about a tunisian case

Introduction

Pregnancy and delivery are considered to be an important transition stage in a woman’s life. Although this experience is emotionally rich, it varies from one person to another and each woman goes through it in her own way.

Objectives

discuss the psychiatric outcomes after a childbirth with somatic complications.

Methods

case report

Results

Mrs X is a 32 years old woman, she has no particular history of illness until she gave birth to her son. He is now three and a half years old and he is an outpatient at the child and teen psychiatry department in a Tunisian hospital. After her delivery, Mrs X had several physical and psychological complications. She was hospitalized in the cardiology department for cardiomyopathy of Meadows for three weeks among it one week in the medical reanimation ward because she needed respiratory assistance. Furthermore, she suffered of left femoral head’s necrosis for which she was operated, and a total hip prosthesis replacement was done. Psychologically, Mrs X. presented a postpartum depression which resolved in its own after 9 months. Ever Since the childbirth, the patient presents symptoms concording with post-traumatic stress disorder and symptoms that may be linked to a specific phobia (fear of birthchild or tokophobia).

Conclusions

In addition to the usual health care provided to women during pregnancy and after childbirth, looking for mental health disturbances and eventually referring them for psychiatric assessment is important specially for women who have experienced traumatic events during the pregnancy or the delivery

Conflict of interest

No significant relationships.

Lockdown: A chance to strengthen the relationship or to widen the gap for tunisian couples?

Introduction

General lockdown due to the outbreak of Corona virus is a major change in people’s lives. Some mental health professionals consider it as a traumatic event with potentially serious psychiatric repercussions, especially on married couples.

Objectives

Determine the consequences of the lockdown on married couples.

Methods

An online survey conducted on social media during Mai 2020.

Results

A total of 223 married persons filled our survey with 86,1% females. Marriage was traditional in 17%, through mutual friends and acquaintances in 0,4% and after a love story in 84,3%. Families were not consenting to the marriage in 5,4% and 28,7% of participants did not consider that they knew their partner enough prior to marriage. The mean duration of marriage was 2 years and 10 months. Having children was reported in 77,1%. Before the general lockdown, 1,79% described their relationship as “bad” compared to 5,82% during; sharing house chores raised from 56,44% to 68,44%. And taking care of children by both parents during the lockdown raised also from 55% to 67,22%. Frequency of sexual intercourse was the same in 57,4% and lower in 23,8%. The lockdown was an opportunity to discover new things in their partner for 28,4% and 19,7% did not consider the lockdown as a chance to spend more time with their partner.

Conclusions

The lockdown gave us a chance to study the impact of the absence of social life on married couples.

Disclosure

No significant relationships.

Optimization of morphine extraction method for the assay of its urinary 3-glucuronideconjuguate by gas chromatography-mass spectrometry

In the field of doping, a great interest is carried for the analysis of morphine, a powerful narcotic analgesic opiate which use is prohibited during competitions. In order to confirm the abnormal analytical result in our anti-doping laboratory, a sensitive and selective gas chromatography-mass spectrometry (GC-MS) method was performed for the quantification of urinary morphine. As sample preparation is a key step for the determination of drugs in biological samples, the aim of this work consists of the optimization of the urinary human sample pretreatment conditions before quantification by GC/MS. Enzymatic hydrolysis associated with liquid-liquid extraction constitute the major pre-treatment steps. Our study has first focused on the optimization of the extraction solvents then to enzymatic hydrolysis which morphine is released from its glucuronide conjugated form. Onboard premiums, a study involving the effect of "amount of enzyme", "incubation temperature" and "duration of hydrolysis" was conducted. This univariate study has enabled us to evaluate the influence of each of these operating variables on the area ratio of morphine to the internal standard (A_morphine/A_IS) response and to set the experimental fields for each one of them. Based on these results, an experimental design was established using the Box-Behnken model to determine, by multivariate analysis, the optimal operating conditions maximizing the "A_mophine/A_IS" response. After validation, the analysis of response surface makes it possible to set the optimum operating conditions, which the ratio "A_morphine/A_IS" is maximized. The retained conditions for enzymatic hydrolysis are 160μl of Escherichia coli glucuronidase enzyme during 6hours of incubation at a temperature of 36°C. The solvent mixture Methyl-t-Butyl Ether/isopropanol (4:1, v/v) was selected since it has improved morphine extraction from the urinary matrix allowing a gain of 50% when compared to that used in our routine laboratory. Our developed extraction method can be successfully applied for our forensic anti-doping analysis of morphin in human sample urine.

Dyspareunia After Childbirth: Does Psychosocial Context Play a Role?

Introduction

Dyspareunia is defined as persistent or recurrent genital pain that occurs just before, during or after intercourse. Dyspareunia after childbirth is quite common and have a range of repercussions to women's lives, including their sexual functioning. It could be affected by different risk factors. While role of obstetric factors including mode of delivery has been largely investigated, the influence of psychosocial factors remains unclear.

Aims

Our purpose was to determine frequency of postpartum dyspareunia and identify related psychosocial factors.

Methods

Thirty women between 2 and 6 months postpartum were recruited in consultation of maternity and neonatology center of Tunis. Data were taken from medical file and questionnaire designed to record psychosocial data and postpartum sexual function.

Results

The mean age of women was 28.74 ± 8.4 years. Dyspareunia was reported by 43.33% of women. Dyspareunia was not associated to professional status. On the other hand, dyspareunia was significantly associated to fatigue (P = 0.024), lack of familial support (P = 0.03), conjugal conflicts (P = 0.01).

Conclusion

We have found an association between dyspareunia after childbirth and several psychosocial factors, pointing out the influence of social and psychological aspects in the sexual function in women. Thus, management of sexual disorders should take in consideration psychological dimension and involve an appropriate psychological care.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Simple and efficient approach to synthesis of [1,2,4]triazolo[4,3-b][1,2,4,6]thiatriazine- 1-oxides from N-triazol-3-ylamidines

A facile method for the synthesis of [1,2,4]triazolo[4,3-b][1,2,4,6]thiatriazine 1-oxides 3a–h is presented. The approach involves a reaction between N-triazol-3-ylamidines 2a–h and thionyl chloride in the presence of pyridine. The structures of the synthesized compounds were confirmed by spectral studies including IR, 1H NMR, 13C NMR, MS and elemental analysis.

Antioxidant properties of Artemisia herba-alba and Eucalyptus camaldulensis essentials oils on malathion-induced reproductive damage in rat

Malathion (M) is an organophosphorus pesticide of utmost concern because of its adverse effects on non-targeted organisms.

Existe-t-il un lien entre les traumatismes infantiles et la genèse de comportements impulsifs chez les patients bipolaires ?

Introduction

L’impulsivité est reconnue comme un facteur prédisposant aux conduites addictives et aux comportements suicidaires chez les patients bipolaires. Notre objectif était d’étudier l’impulsivité trait chez des sujets atteints de trouble bipolaire comparativement à des sujets témoins et déterminer si l’impulsivité trait identifierait un sous-groupe cliniquement distinct et homogène de trouble bipolaire. Le rôle joué par les expériences traumatiques infantiles sur le développement de comportements impulsifs chez les bipolaires a été également étudié.

Méthodes

Étude de type cas témoins, durant une période de six mois (juillet 2012–décembre 2012). Les patients atteints de trouble bipolaire de type I, II ou non spécifié en normothymie ont été recrutés au service de psychiatrie C de l’hôpital Razi. Les sujets témoins ont été recrutés dans le service d’ORL de l’hôpital militaire de Tunis. Les deux groupes ont été comparés pour l’âge, le sexe et le niveau d’éducation. Ils ont ensuite été comparés pour les scores de la Barratt Impulsivity Scale (BIS-10) et pour les scores du Childhood Trauma Questionnaire (CTQ).

Résultats

Les scores d’impulsivité totale et les sous-scores d’impulsivité motrice et cognitive des sujets souffrant de trouble bipolaire étaient significativement plus élevés que ceux des sujets témoins (avec respectivement p = 0,001; p = 0,005; p = 0,002). Il existait une différence statistiquement significative entre le groupe des bipolaires et des témoins en ce qui concerne le CTQ total (p < 10,3) et les sous-scores d’abus émotionnel (p < 10,3), de négligence physique (p = 0,01) et d’abus physique (p = 0,001) qui étaient plus élevés chez les patients. Il existait une corrélation entre le score total moyen au CTQ et le score total moyen d’impulsivité à la BIS-10 chez les sujets souffrant de troubles bipolaires (p = 004). L’impulsivité était associée à une enfance chargée d’évènements traumatiques, en particulier chez les patients bipolaires.

Conclusion

L’utilisation systématique d’un indicateur de l’impulsivité, en particulier le BIS, permettrait d’identifier les patients bipolaires à grand risque de conduites addictives et d’autres conduites à risques, afin de développer des mesures de prise en charge thérapeutique appropriées pour ces derniers vu leur mauvaise réponse au traitement.

A multiplex-PCR assay for identification of the quarantine plant pathogen Xanthomonas axonopodis pv. phaseoli

In this study we developed an algorithm to screen for all exact molecular signatures of the quarantine pathogen Xanthomonas axonopodis pv. phaseoli (Xap), based on available data of the presence or absence of virulence-associated genes. The simultaneous presence of genes avrBsT and xopL is specific to Xap. Therefore we developed a multiplex PCR assay targeting avrBsT and xopL for the molecular identification of Xap. The specificity of this multiplex was validated by comparison to that of other molecular identification assays aimed at Xap, on a wide collection of reference strains. This multiplex was further validated on a blind collection of Xanthomonas isolates for which pathogenicity was assayed by stem wounding and by dipping leaves into calibrated inocula. This multiplex was combined to the previously described X4c/X4e molecular identification assay for Xap. Such a combination enables the molecular identification of all strains of Xanthomonas pathogenic on bean. Results also show that assay by stem wounding does not give reliable results in the case of Xap, and that pathogenicity assays by dipping should be preferred.

Synthesis, spectroscopic characterization and X-ray structure of [1,2a]benzimidazol-2-yl amidine

[1,2a]Benzimidazol-2-yl amidine was synthesized by adding cyclopentanamine to iminoester in ethanol. The structure of amidine 1 was characterized by IR, 1H NMR, 1H-1H NOESY, 13C NMR, DEPT, XHCOR spectra, thermogravimetric analysis (TGA), differential thermal analysis (DTA), differential scanning calorimetry thermograms (DSC), elementary analysis as well as by X-ray diffraction. The single crystals suitable for X-ray measurement were obtained by recrystallization at room temperature. The amidine group of a model was found to have Z configuration in the crystal. This compound crystallizes in a P2(1)/n monoclinic unit cell with parameters a=12.679(2) Å, b=8.468(3) Å, c=13.108(2) Å, β=96.538(2)°, V=1398.2 Å3 and Z=4.

In vitro and in vivo efficacy of photofrin and pheophorbide a, a bacteriochlorin, in photodynamic therapy of colonic cancer cells

This study was designed to investigate the efficacy of photodynamic therapy (PDT) in treating colonic cancer in a preclinical study. Photofrin, a porphyrin mixture, and pheophorbide a (Ph a), a bacteriochlorin, were tested on HT29 human colonic tumor cells in culture and xenografted into athymic mice. Their pharmacokinetics were investigated in vitro, and the PDT efficacy at increasing concentrations was determined with proliferative, cytotoxic and apoptotic assessments. The in vivo distribution and pharmacokinetics of these dyes (30 mg/kg, intraperitoneal) were investigated on HT29 tumor-bearing nude mice. The inhibition of tumor growth after a single 100 J/cm2 PDT session was measured by the changes in tumor volume and by histological analysis of tumor necrosis. PDT inhibited HT29 cell growth in culture. The cell photodamage occurred since the time the concentrations of Ph a and Photofrin reached 5.10(-7) M (or 0.3 microg/mL) and 10 microg/mL, respectively. A photosensitizer dose-dependent DNA fragmentation was observed linked to a cleavage of poly(ADP-ribose) polymerase and associated with an increased expression of mutant-type p53 protein. PDT induced a 3-week delay in tumor growth in vivo. The tumor injury was corroborated by histological observation of necrosis 48 h after treatment, with a correlated loss of specific enzyme expression in most of the tumor cells. In conclusion, PDT has the ability to destroy human colonic tumor cells in vitro and in vivo. This tumoricidal effect is likely associated with a p53-independent apoptosis, as HT29 cells express only mutated p53. The current study suggests a preferential use of Photofrin in PDT of colonic cancer because it should be more effective in vivo than Ph a as a consequence of better tumor uptake.

Dual effect of laparoscopy on cell-mediated immunity

Laparoscopic influence on cell-mediated immunity and tumour evolution is controversial. The objective of the present study was to assess tumour growth and immune patterns after laparoscopy on an experimental study. Lewis rats, bearing an intrapancreatic ductal carcinoma randomly underwent one of the following 2-hour procedures: anaesthesia, laparotomy or CO(2) pneumoperitoneum. Cell-mediated immunity was investigated through determination of serum IL1beta concentrations by ELISA and TNFalpha, IL6 and iNOS gene transcriptions in blood white cells and peritoneal cells by RT-PCR 1 day after operation. Tumour growth and spread patterns were assessed on anatomopathological examination 2 weeks after surgery. Tumour growth and spread were unaffected no matter what procedure was applied, but port-site seeding occurred in half of the cases undergoing laparoscopy. No significant change in acute-phase protein response, represented by IL1beta serum concentration, was found after laparoscopy. TNFalpha, IL6 and inducible NO synthase gene transcriptions were enhanced in blood white cells and depressed in peritoneal immune cells after laparoscopy. In our experimental conditions, cell-mediated immune response to CO(2) pneumoperitoneum seems to be a good systemic immune activation and a less acute peritoneal immune response as opposed to control laparoscopy. This early impairment of peritoneal macrophage immune activity, observed after a long-lasting CO(2) pneumoperitoneum, might be responsible for the high rate of port site recurrence.

Human pancreatic carcinoma cells are sensitive to photodynamic therapy in vitro and in vivo

BACKGROUND

The aim of this study was to assess the efficiency of photodynamic therapy (PDT) on human pancreatic cancer cells in vitro and in an animal model.

METHODS

Human pancreatic tumour cell lines were submitted to PDT with pheophorbide a (Ph a), a chlorophyll derivative, in culture and after grafting into athymic mice. Ph a was tested in culture (10-10-10-5 mol/l) with a 5-J/cm2 energy treatment and on tumour-bearing Nude mice (30 mg/kg intraperitoneally) with a 100-J/cm2 PDT session. The effect of PDT was assessed in vitro using proliferative, apoptotic and clonogenic tests and in vivo on tumour growth and on the induction of tumour necrosis.

RESULTS

PDT inhibited tumour cell growth in culture by affecting DNA integrity. This tumour cell photodamage started at low concentration (10-7 mol/l) as corroborated by clonogenic and tumour growth tests. A strong necrosis was achieved in vivo with a single PDT session.

CONCLUSION

PDT destroyed human pancreatic carcinoma after low photosensitizer supply and weak energy application. It exerted this tumoricidal effect via apoptosis induction with a gentle protocol, and apoptosis and/or necrosis with a stronger protocol.

Increased tumor growth and spread after laparoscopy vs laparotomy: influence of tumor manipulation in a rat model

BACKGROUND

The use of laparoscopy for assessment and treatment of malignant tumors remains controversial. The aim of this study was to evaluate the impact of tumor manipulation during laparoscopy compared with that of conventional laparotomy on growth and spread of an intraperitoneal tumor in the rat in a randomized, controlled trial.

METHODS

Thirty 2-month-old male Lewis rats received a single-site intrapancreatic inoculation of a ductal adenocarcinoma. Fourteen days after cancer implanting, two groups of six animals each underwent a laparotomy (30 min 6 mmHg CO2 pneumoperitoneum). The tumor was manipulated in the one group, and exclusively visualized in the other. In two other groups, a midline laparotomy with (n = 6) or without (n = 6) tumor manipulation was performed. Animals in the control group (n = 6) underwent no procedure. Tumor volume, tumor mass, local regional invasion incidence, lymph node involvement, and liver and lung metastases were evaluated on 28-day tumors.

RESULTS

No difference in tumor growth and spread was observed between laparoscopy and laparotomy when tumor manipulation was not carried out. Tumor manipulation increased tumor growth significantly in the laparotomy group, but not in the laparoscopy one. Tumor metastases were correlated to tumor growth and increased significantly after manipulation in both groups. There was no port-site or conventional wound seeding in either the surgical procedure.

CONCLUSIONS

This study showed that manipulation is the main factor acting on tumor dissemination in both laparoscopy and laparotomy. Laparoscopic surgery had a beneficial effect on local tumor growth compared with laparotomy in the case of tumor manipulation. This beneficial effect of laparoscopic surgery may be related to a better preservation of immune function in the early postoperative period.

Effects of cholecystokinin octapeptide on a pancreatic acinar carcinoma in the rat

PURPOSE

To investigate the effects of increasing concentrations of cholecystokinin octapeptide (CCK-8) on a pancreatic acinar adenocarcinoma.

METHODS

Growth of the tumour was estimated in vivo on rats bearing a subcutaneous pancreatic carcinoma, and in vitro on primary cultured tumour cells. CCK receptors were characterized by binding assays.

RESULTS

CCK-8, administered for 12 successive days, exerted a biphasic action on tumour growth: a dose-dependent stimulation with low doses (0.1 and 0.5 microg/kg) and inhibition with high doses (2 and 4 microg/ kg) as shown by respective increases and decreases in tumor volume, protein, RNA and amylase contents. In cell cultures, [3H]thymidine incorporation was dose-dependently increased with 10-(10) to 10(-8) M CCK-8 and inhibited with 10(-7) M. Both effects were completely suppressed by the CCK-receptor antagonists CR 1409 and L 364,718 (10(-4) M). Binding studies showed the overexpression of two classes of CCK-A receptors of low and high affinity when compared to the normal pancreas which was less sensitive to CCK-8.

CONCLUSIONS

CCK-8 exerts a biphasic growth response on the acinar pancreatic carcinoma, mediated by two classes of CCK-A receptors overexpressed in the tumour.

Role of nitric oxide in pancreatic tumour growth: in vivo and in vitro studies

Nitric oxide (NO), an endogenous free radical, has been implicated in a wide range of biological functions. NO is generated enzymatically from the terminal guanidinonitrogen of L-arginine by nitric oxide synthase (NOS). Despite intensive investigations, the role of NO--either as the primary product of the L-arginine/NOS pathway or provided from the NO donor sodium nitroprusside (SNP)--in carcinogenesis and tumour cell growth remains unclear and controversial. The objective of this study was to examine the growth effects of NO on a ductal pancreatic adenocarcinoma in the rat and on a human pancreatic tumour cell line (HA-hpc2). In vivo, both SNP and endogenous induction of NO by endotoxins [lipopolysaccharide (LPS)] plus L-arginine significantly reduced the tumour growth. To investigate the mechanisms of NO anti-tumour growth action, the effects of either the SNP or L-arginine/NOS pathway were analysed on the HA-hpc2 cell line. Nitrite/nitrate production, NOS activity and iNOS expression [assessed by reverse transcription-polymerase chain reaction (RT-PCR)] were tested and related to growth (assessed by [3H]thymidine incorporation assay) and apoptosis (assessed by internucleosomal DNA cleavage). SNP exerted a dual effect on tumour cells: stimulation of the proliferation up to 1 mM and inhibition at higher concentrations. These effects were related to NO production. Both proliferative and cytostatic responses were inhibited by NO scavenger 2-phenyl-4,4,5,5-tetramethyl-hemidazoline-1-oxyl3-oxide (carboxy-PTIO). The marked apoptotic DNA fragmentation induced by SNP was also abolished by PTIO association. Unlike macrophages, the human pancreatic tumour cells did not seem to express intrinsically the L-arginine/NOS pathway. Macrophages were activated by HA-hpc2 cells as well as by LPS plus cytokines [interleukin (IL)-1beta plus tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma]. In HA-hpc2/macrophage co-cultures, NOS activity and inducible NOS (iNOS) transcription were stimulated, whereas an antiproliferative response was observed. These effects were related to both macrophage amount and NO production. Addition of LPS plus cytokines to co-cultures doubled iNOS activity, nitrite/nitrate production and tumoricidal effect. These data suggest the involvement of NO in pancreatic tumour growth and support the fact that generation of high levels of NO with potential production of endogenous reactive nitrogen intermediates may contribute to induction of apoptosis and tumour growth inhibition.

Effect of the gastrin-releasing peptide antagonist BIM 26226 and lanreotide on an acinar pancreatic carcinoma

The effects of a potent specific gastrin-releasing peptide receptor antagonist, BIM 26226 ([D-F5 Phe6, D-Ala11] bombesin (6-13) OMe), and the long-acting somatostatin analogue, lanreotide (BIM 23014), on the growth of an acinar pancreatic adenocarcinoma growing in the rat or cultured in vitro were investigated. Lewis rats bearing a pancreatic carcinoma transplanted s.c. in the scapular region, were treated with gastrin-releasing peptide (30 microg/kg per day), BIM 26226 (30 and 100 microg/kg per day) and lanreotide (100 microg/kg per day) alone or in combination for 14 successive days. Chronic administration of BIM 26226 and lanreotide significantly inhibited the growth of pancreatic tumours stimulated or not by gastrin-releasing peptide (GRP), as shown by a reduction in tumour volume, protein, ribonucleic acid, amylase and chymotrypsin contents. This effect was more pronounced with 100 microg/kg per day BIM 26226 than with 30 microg/kg per day. However, BIM 26226 and lanreotide, given together, did not exert any additive effect on GRP-treated and -untreated tumours. In cell cultures, both BIM 26226 and lanreotide (10(-6) M) inhibited [3H]thymidine incorporation in tumour cells induced or not by GRP, but no increased effect was observed after combined treatment with both agents. Binding studies showed that BIM 26226 had a high affinity for GRP receptors in tumour cell membranes (IC50 = 6 nM). These results from in vivo and in vitro experiments suggest that BIM 26226 and lanreotide are able to reduce the growth of an experimental acinar pancreatic tumour. Thus, these agents represent interesting steps toward the development of new approaches for treatment of pancreatic carcinomas.

Inactivation of p53 in normal human cells increases G2/M arrest and sensitivity to DNA-damaging agents

p53 mutations are found in about 70% of human cancers. In order to evaluate the role of these mutations in response to chemotherapeutic agents, it is important to distinguish between p53 response to DNA-damaging agents in normal and in tumour cells. Here, using normal human fibroblasts (NHFs), we show that cisplatin and UV radiation induce G2/M arrest which is temporally linked to p53-protein induction. To study the contribution of p53 to this G2/M arrest, we inhibited p53 induction in NHFs using p53 anti-sense oligonucleotides. Following exposure of NHFs to UV radiation, the inhibition of p53-protein induction leads to a greater accumulation of cells in the G2/M phase, but also to a decreased fraction of cells in the G1 phase. We propose that p53 does not induce G2/M arrest directly, and that the extent of this arrest may depend on the fraction of cells that do not stop at the G1 phase following exposure to DNA-damaging agents. Furthermore, inhibition of p53-protein induction leads to increased sensitivity of NHFs to UV radiation. These results suggest that inhibition of p53 protein enhances sensitivity to DNA-damaging agents in normal human cells.

In vivo laser-induced fluorescence imaging of a rat pancreatic cancer with pheophorbide-a

Laser-induced fluorescence (LIF) of pheophorbide-a (Ph-a) was used for imaging of a rat pancreatic tumor. Using a dimensionless function (the ratio of Ph-a fluorescence by bluish autofluorescence), the fluorescence contrasts between excised tumors and their paired pancreas were investigated up to 48 h after a 9 mg kg-1 Ph-a intravenous administration. Among five tested excitation wavelengths, 355 and 610 nm excitations gave the best distinctive contrasts, both 48 h after dye injection. The LIF imaging of six intrapancreatic tumors and six healthy pancreas was carried out in vivo using two laser excitations: 355 nm (Nd:YAG + tripling) for bluish autofluorescence and 610 nm (rhodamine 6G dye) for reddish autofluorescence and dye emission. Images were recorded through bandpass filters at 470 and 640 nm (autofluorescence) and at 680 nm (dye + autofluorescence) with an intensified charged-coupled device camera. Autofluorescence as Ph-a fluorescence images did not allow accurate LIF diagnosis of pancreatic carcinoma. An image processing, including for each pixel a computed division of Ph-a fluorescence (after subtraction of reddish autofluorescence) by bluish autofluorescence intensity generated poorly contrasted tumor images in five of six and false tumor localization in one of three of the tumor-bearing pancreas. A fitting of the digital 640 nm autofluorescence up to the mean 680 nm fluorescence intensity in pancreas prior to subtraction allowed a safe diagnosis to be made with well-contrasted tumor images. To assess automation ability of the processing, a same fitting coefficient (mean of individual values) was applied. In this way, false-negative (one of six) and false-positive (two of six) images were present in tumor-bearing animals as false-positive in one-half of the controls. A successful standardized procedure was then applied with a normalization of 640 and 680 nm pancreas intensities to a same set threshold prior processing. In opposition to thin-layered hollow organs, such as bronchial tube or digestive tract, LIF imaging of carcinoma inserted in a compact organ is exhausting. The use of a dye excitable in the red wavelength range (610 nm for Ph-a) may partly solve this problem, rendering LIF imaging more accurate and potentially automated.

Photodynamic imaging of a rat pancreatic cancer with pheophorbide a

Laser-induced fluorescence of pheophorbide a (Ph-a) was used for in vitro photodynamic imaging (PDI) of a rat pancreatic acinar tumor. A 400 nm excitation induced a 470 nm autofluorescence and a 678 nm dye fluorescence in tumors and their surrounding pancreas 24 h after a 9 mg kg-1 body weight Ph-a intravenous administration. With lower intensities in these blood-rich tumors than in pancreas, Ph-a fluorescence signals are unable to provide tumor images. A dimensionless function (the ratio of Ph-a fluorescence by autofluorescence, called Rt for the tumor and Rp for the pancreas) was used for fluorescence contrast calculation (C = Rt/Rp) between six tumors and their paired pancreas. Among five available laser excitation wave-lengths, only the 355 nm excitation gave a distinctive contrast (C = 1.5). The PDI of six intrapancreatic tumors and their intraperitoneal metastasis and of two control normal pancreas was thus performed ex vivo using a 355 nm excitation source delivered by a tripled Nd:YAG laser and a charged-coupled device camera. Fluorescence images were recorded at 680 nm (dye), 640 nm (background) and 470 nm (autofluorescence) through three corresponding 10 nm width bandpass filters. Computed division for each pixel of Ph-a fluorescence values by autofluorescence generated false color image. In this way, contrasted tumor images were obtained. But in five out of six animals false-positive images were present due to an autofluorescence decrease in some normal pancreatic areas. A 470 nm autofluorescence imaging on the same tumors gave in all cases false-positive image and false-negative in half of the cases. These observations suggest that autofluorescence alone is unable to achieve accurate PDI of pancreatic carcinoma and that using Ph-a as a PDI dye needs strong improvements.

Expression and characterization of gastrin-releasing peptide receptor in normal and cancerous pancreas

The biochemical and pharmacological characteristics of specific binding sites for gastrin-releasing peptide (GRP) were investigated in normal exocrine pancreas and in an azaserine-induced pancreatic carcinoma in the rat, under similar experimental conditions. Cells from both types of tissues contained rapid, reversible, temperature-dependent, and highly specific binding sites for GRP. Scatchard analysis of equilibrium data obtained with normal and tumor plasma membranes indicated a single class of high-affinity sites (KD = 0.42 +/- 0.06 and 0.35 +/- 0.05 nM, respectively), but the number of GRP receptors was significantly different (Bmax = 31 +/- 4.5 and 189 +/- 20 fmol/mg protein, respectively). Binding of 125I-GRP1-27 was sensitive to GTP analogues, suggesting that the GRP receptor is functionally linked to a guanyl regulatory protein; however, the wheat germ agglutinin-agarose purified receptor had lost this G-protein activity. Cross-linking of 125I-GRP1-27 either to normal and neoplastic cells or to crude membranes, solubilized membrane proteins, and partially purified receptors revealed the presence of a specific MW 75-kDa polypeptide. N-Glycanase treatment reduced this apparent MW to about 45 kDa. Together, these data suggest that normal and tumor pancreatic cells contain a specific GRP receptor that is expressed more on malignant pancreatic tissues.

Experimental pancreatic cancer in the rat treated by photodynamic therapy

Selective histological necrosis of experimental pancreatic carcinoma by photodynamic therapy (PDT) has been successful with haematoporphyrin derivatives and phthalocyanine as photosensitizers. This report describes the feasibility of PDT with pheophorbide A as the photosensitizer to treat azaserine-induced pancreatic rat carcinoma and analyses survival of the animals. An organ distribution study 24 h after pheophorbide A administration (9 mg/kg intravenously) gave a selectivity ratio of 13.5:1 between tumour and surrounding tissue. Light of 660 nm and 100 J/cm2 induced selective necrosis of the tumour. Six of nine rats were cured in 120 days whereas all 36 control animals died within 35 days (P < 0.01). The pancrease and hepatic pedicle were relatively unaffected by PDT, but the duodenum was injured.

Inhibition of growth of a transplanted rat pancreatic acinar carcinoma with CCK-8

Gastrointestinal hormones and neuropeptides are known to regulate growth of various normal gastrointestinal tissues and many cancers. Since cholecystokinin (CCK) is considered the most potent trophic factor for the exocrine pancreas, we studied its effect on growth of an acinar cell tumor, initially induced by azaserine and transplanted to the rat, in comparison with the normal pancreas. When tumors became palpable, rats were treated three times daily for 12 or 14 days with CCK-8 or NaCl 0.9% (controls) alone or in combination with the CCK receptor antagonist CR1409 (10 mg/kg) administered subcutaneously twice daily. Then tumors and pancreata were analyzed for their size, composition, and CCK receptors. Tumor volume, weight, and protein content, RNA, DNA, and enzymes decreased after CCK-8 treatment in a dose-dependent manner, the maximal effect being observed with 4-micrograms/kg treatment. This inhibitory effect was partially suppressed by CR1409, which by itself also reduced tumor growth, but to a lesser degree. CCK-8 exerted a stimulating effect on growth of the normal pancreas with low doses (1 and 2 micrograms/kg) and an inhibitory effect or no effect with a higher dose (4 micrograms/kg). CR1409 prevented this latter effect, but did not affect by itself the normal pancreas. These findings suggest that CCK-8 inhibits growth of an acinar cell tumor grafted to the rat; this effect is mediated by the occupation of specific CCK receptors present in high density on these cells. In contrast, CCK-8 exerts a biphasic effect on the normal pancreas as a function of its dose.