Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach / Introdução do gene resistente à ferragem da folha bacteriana (BLB), xa7 na variedade MARDI elite, MR219 por abordagem de backcrossing assistida por marcador (MABC)

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

Resumo A mancha bacteriana das folhas (BLB) é uma das principais doenças do arroz na Malásia. Essa doença causa perdas substanciais de rendimento de até 70%. O desenvolvimento de variedades de arroz que herdaram características de resistência ao BLB é uma abordagem crucial para promover e sustentar a indústria do arroz na Malásia. Portanto, o objetivo deste estudo foi aumentar os caracteres BLB resistentes a doenças da variedade comercial MR219 de alto rendimento por meio de uma abordagem de cruzamento retrocruzamento com ferramenta de apoio de seleção assistida por marcador (MAS). O gene de resistência a BLB de amplo espectro, Xa7 do pai doador IRBB7, foi introgressado no MR219 suscetível (pai recorrente) usando dois marcadores flanqueadores ID7 e ID15. No BC3F4, conseguimos gerar 19 linhagens introgressadas com o gene Xa7 homozigoto e apresentamos características de resistência como genitor doador quando desafiado com Xanthomonas oryzae pv. oryzae por inoculação artificial. O pai recorrente MR219 e a variedade controle, MR263, estavam gravemente infectados pela doença. As linhas melhoradas exibiram características morfológicas e de desempenho de rendimento semelhantes às da variedade elite, MR219. Duas linhas, PB-2-107 e PB-2-34, foram escolhidas como linhas potenciais por causa de seus desempenhos excelentes em comparação com a mãe, MR219. Este estudo demonstra uma história de sucesso de aplicação de MAS no desenvolvimento de linhas de arroz melhoradas com resistência a doenças contra a doença BLB.

Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach

Abstract Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

Resumo A mancha bacteriana das folhas (BLB) é uma das principais doenças do arroz na Malásia. Essa doença causa perdas substanciais de rendimento de até 70%. O desenvolvimento de variedades de arroz que herdaram características de resistência ao BLB é uma abordagem crucial para promover e sustentar a indústria do arroz na Malásia. Portanto, o objetivo deste estudo foi aumentar os caracteres BLB resistentes a doenças da variedade comercial MR219 de alto rendimento por meio de uma abordagem de cruzamento retrocruzamento com ferramenta de apoio de seleção assistida por marcador (MAS). O gene de resistência a BLB de amplo espectro, Xa7 do pai doador IRBB7, foi introgressado no MR219 suscetível (pai recorrente) usando dois marcadores flanqueadores ID7 e ID15. No BC3F4, conseguimos gerar 19 linhagens introgressadas com o gene Xa7 homozigoto e apresentamos características de resistência como genitor doador quando desafiado com Xanthomonas oryzae pv. oryzae por inoculação artificial. O pai recorrente MR219 e a variedade controle, MR263, estavam gravemente infectados pela doença. As linhas melhoradas exibiram características morfológicas e de desempenho de rendimento semelhantes às da variedade elite, MR219. Duas linhas, PB-2-107 e PB-2-34, foram escolhidas como linhas potenciais por causa de seus desempenhos excelentes em comparação com a mãe, MR219. Este estudo demonstra uma história de sucesso de aplicação de MAS no desenvolvimento de linhas de arroz melhoradas com resistência a doenças contra a doença BLB.

Introgression of bacterial leaf blight (BLB) resistant gene, Xa7 into MARDI elite variety, MR219 by marker assisted backcrossing (MABC) approach.

Bacterial leaf blight (BLB) is one of the major rice diseases in Malaysia. This disease causes substantial yield loss as high as 70%. Development of rice varieties which inherited BLB resistant traits is a crucial approach to promote and sustain rice industry in Malaysia. Hence, this study aims were to enhance BLB disease resistant characters of high yielding commercial variety MR219 through backcross breeding approach with supporting tool of marker-assisted selection (MAS). Broad spectrum BLB resistance gene, Xa7 from donor parent IRBB7 were introgressed into the susceptible MR219 (recurrent parent) using two flanking markers ID7 and ID15. At BC3F4, we managed to generate 19 introgressed lines with homozygous Xa7 gene and showed resistant characteristics as donor parent when it was challenged with Xanthomonas oryzae pv. oryzae through artificial inoculation. Recurrent parent MR219 and control variety, MR263 were found to be severely infected by the disease. The improved lines exhibited similar morphological and yield performance characters as to the elite variety, MR219. Two lines, PB-2-107 and PB-2-34 were chosen to be potential lines because of their outstanding performances compared to parent, MR219. This study demonstrates a success story of MAS application in development of improved disease resistance lines of rice against BLB disease.

Fabrication of a three-dimensional temporomandibular joint model for arthrocentesis and arthroscopy simulation.

Arthrocentesis and arthroscopy are relatively safe treatments for arthrogenic temporomandibular disorders. Hands-on training in both procedures is essential for surgeons to become competent. In this study, a three-dimensional (3D) temporomandibular joint (TMJ) prototype was developed at a relatively low cost, and arthrocentesis and arthroscopy were performed successfully on the model. Despite its limitations, this model is a viable adjunct to TMJ surgical training and can be fabricated easily by any training centre with a 3D printer.

Analysis of complications following multidisciplinary functional intervention in paediatric craniomaxillofacial deformities.

Paediatric craniomaxillofacial (CMF) surgery requires a multidisciplinary team approach to ensure the optimal and holistic management of children with craniofacial deformities. The aim of this retrospective study was to analyse the complications following functional interventions among 34 CMF deformity patients in a single multidisciplinary craniofacial centre. Electronic data including patient demographic characteristics and clinical entry were analysed. Inclusion criteria were all paediatric patients with CMF deformities who underwent various functional interventions. A total of 64 interventions (48 intermediate and 16 definitive) were conducted. Based on the Sharma classification of complications, 20.3% were type I, 4.7% were type II, 1.6% were type III, and 4.7% were type IV . Most complications were type I, which included local infection (3.1%) and premature opening of tarsorrhaphy (3.1%). More serious complications (types III and IV) included temporary visual loss (1.6%) and intraoperative haemorrhage (1.6%). Although a low complication rate was observed in intermediate interventions, a higher complication rate was observed in more complex definitive interventions such as monobloc distraction osteogenesis. Although most complications were manageable, effective prevention remains mandatory, as serious complications may lead to permanent damage and mortality. This analysis highlights the importance of a multidisciplinary team approach to optimize the outcomes in CMF patient management.

Hypernasality in singing among children with cleft palate: a preliminary study.

The aim of this study was to document differences in hypernasality during speaking and singing among children with cleft palate and to compare nasality score ratings of trained and untrained listeners. Twenty subjects with cleft palate aged between 7 and 12 years participated in this study. Audio recordings were made of the children reading a passage and singing a common local song, both in the Malay language. The degree of hypernasality was judged through perceptual assessment. Three trained listeners (a speech therapist, a classical singer, and a linguistic expert - all academicians) and two untrained listeners (a cleft volunteer worker and a national high school teacher) assessed the recordings using a visual analogue scale (VAS). Inter-rater and intra-rater reliability for hypernasality in both speaking and singing were verified using the intra-class correlation coefficient (ICC). A significant reduction in hypernasality was observed during singing as compared to speaking, indicating that hypernasality reduces when a child with cleft palate sings. The act of singing significantly reduces hypernasality. The outcome of this study suggests that children with cleft palate would benefit from singing exercises to ultimately reduce hypernasality. However, future research is needed to objectively measure nasality in singing compared to speaking.

Crouzon syndrome: Genetic and intervention review.

Crouzon syndrome exhibits considerable phenotypic heterogeneity, in the aetiology of which genetics play an important role. FGFR2 mediates extracellular signals into cells and the mutations in the FGFR2 gene cause this syndrome occurrence. Activated FGFs/FGFR2 signaling disrupts the balance of differentiation, cell proliferation, and apoptosis via its downstream signal pathways. However, very little is known about the cellular and molecular factors leading to severity of this phenotype. Revealing the molecular pathology of craniosynostosis will be a great value for genetic counselling, diagnosis, prognosis and early intervention programs. This mini-review summarizes the fundamental and recent scientific literature on genetic disorder of Crouzon syndrome and presents a graduated strategy for the genetic approach, diagnosis and the management of this complex craniofacial defect.

Distraction osteogenesis in the surgical management of syndromic craniosynostosis: a comprehensive review of published papers.

Our aim was to summarise current published evidence about the prognosis of various techniques of craniofacial distraction osteogenesis, particularly its indications, protocols, and complications. Published papers were acquired from online sources using the keywords "distraction osteogenesis", "Le Fort III", "monobloc", and "syndromic craniosynostosis" in combination with other keywords, such as "craniofacial deformity" and "midface". The search was confined to publications in English, and we followed the guidelines of the PRISMA statement. We found that deformity of the skull resulted mainly from Crouzon syndrome. Recently craniofacial distraction has been achieved by monobloc distraction osteogenesis using an external distraction device during childhood, while Le Fort III distraction osteogenesis was used in maturity. Craniofacial distraction was indicated primarily to correct increased intracranial pressure, exorbitism, and obstructive sleep apnoea in childhood, while midface hypoplasia was the main indication in maturity. Overall the most commonly reported complications were minor inflammatory reactions around the pins, and anticlockwise rotation when using external distraction systems. The mean amount of bony advancement was 12.3mm for an external device, 18.6mm for an internal device and 18.7mm when both external and internal devices were used. Treatment by craniofacial distraction must be validated by long-term studies as there adequate data are lacking, particularly about structural relapse and the assessment of function.

GENIPAC: A Genomic Information Portal for Head and Neck Cancer Cell Systems.

Head and neck cancer (HNC)-derived cell lines represent fundamental models for studying the biological mechanisms underlying cancer development and precision therapies. However, mining the genomic information of HNC cells from available databases requires knowledge on bioinformatics and computational skill sets. Here, we developed a user-friendly web resource for exploring, visualizing, and analyzing genomics information of commonly used HNC cell lines. We populated the current version of GENIPAC with 44 HNC cell lines from 3 studies: ORL Series, OPC-22, and H Series. Specifically, the mRNA expressions for all the 3 studies were derived with RNA-seq. The copy number alterations analysis of ORL Series was performed on the Genome Wide Human Cytoscan HD array, while copy number alterations for OPC-22 were derived from whole exome sequencing. Mutations from ORL Series and H Series were derived from RNA-seq information, while OPC-22 was based on whole exome sequencing. All genomic information was preprocessed with customized scripts and underwent data validation and correction through data set validator tools provided by cBioPortal. The clinical and genomic information of 44 HNC cell lines are easily assessable in GENIPAC. The functional utility of GENIPAC was demonstrated with some of the genomic alterations that are commonly reported in HNC, such as TP53, EGFR, CCND1, and PIK3CA. We showed that these genomic alterations as reported in The Cancer Genome Atlas database were recapitulated in the HNC cell lines in GENIPAC. Importantly, genomic alterations within pathways could be simultaneously visualized. We developed GENIPAC to create access to genomic information on HNC cell lines. This cancer omics initiative will help the research community to accelerate better understanding of HNC and the development of new precision therapeutic options for HNC treatment. GENIPAC is freely available at http://genipac.cancerresearch.my/ .

The utilization of cranial models created using rapid prototyping techniques in the development of models for navigation training.

INTRODUCTION: Navigation in neurosurgery has expanded rapidly; however, suitable models to train end users to use the myriad software and hardware that come with these systems are lacking. Utilizing three-dimensional (3D) industrial rapid prototyping processes, we have been able to create models using actual computed tomography (CT) data from patients with pathology and use these models to simulate a variety of commonly performed neurosurgical procedures with navigation systems. AIM: To assess the possibility of utilizing models created from CT scan dataset obtained from patients with cranial pathology to simulate common neurosurgical procedures using navigation systems. METHODOLOGY: Three patients with pathology were selected (hydrocephalus, right frontal cortical lesion, and midline clival meningioma). CT scan data following an image-guidance surgery protocol in DIACOM format and a Rapid Prototyping Machine were taken to create the necessary printed model with the corresponding pathology embedded. The ability in registration, planning, and navigation of two navigation systems using a variety of software and hardware provided by these platforms was assessed. RESULTS: We were able to register all models accurately using both navigation systems and perform the necessary simulations as planned. CONCLUSION: Models with pathology utilizing 3D rapid prototyping techniques accurately reflect data of actual patients and can be used in the simulation of neurosurgical operations using navigation systems.

Dysregulation of miR-31 and miR-375 expression is associated with clinical outcomes in oral carcinoma.

OBJECTIVES: To identify differentially expressed miRNA between oral squamous cell carcinoma (OSCC) and non-cancer (NC) and to associate these with clinico-pathological parameters. MATERIALS AND METHODS: miRNA microarray profiling was utilized to obtain the expression profile of miRNAs in four OSCC and four NC samples. The expression of miR-31 and miR-375 was further validated in 26 OSCC and three NC samples using real-time-PCR. The association between miRNA expression and clinico-pathological parameters was tested by univariate and multivariate analyses. RESULTS: Microarray profiling demonstrated that 15 and four miRNAs were up-regulated and down-regulated, respectively, in OSCC as compared with NC. miR-31 and miR-375 were validated as up- and down-regulated miRNAs, respectively. In univariate analyses, expression of miR-31 was significantly elevated in early stage, tumours with no metastatic nodes and those from the buccal mucosa. By contrast, low miR-375 expression was significantly associated with late stage disease, larger tumour size and the non-cohesive type of pattern of invasion in OSCC. The association between miR-31 expression with tumour staging and site and miR-375 with tumour staging remained significant in multivariate analyses. CONCLUSIONS: This study has identified 19 miRNAs significantly associated with OSCC, and expressions of miR-31 and miR-375 were significantly related with clinico-pathological parameters suggesting they could be important in driving oral tumourigenesis.

Three-dimensional anatomical accuracy of cranial models created by rapid prototyping techniques validated using a neuronavigation station.

In neurosurgery and ear, nose and throat surgery the application of computerised navigation systems for guiding operations has been expanding rapidly. However, suitable models to train surgeons in using navigation systems are not yet available. We have developed a technique using an industrial, rapid prototyping process from which accurate spatial models of the cranium, its contents and pathology can be reproduced for teaching. We were able to register, validate and navigate using these models with common available navigation systems such as the Medtronic StealthStation S7®.

Genome-wide analysis of oral squamous cell carcinomas revealed over expression of ISG15, Nestin and WNT11.

BACKGROUND: Multistep pathways and mechanisms are involved in the development of oral cancer. Chromosomal alterations are one of such key mechanisms implicated oral carcinogenesis. Therefore, this study aims to determine the genomic copy number alterations (CNAs) in oral squamous cell carcinoma (OSCC) using array comparative genomic hybridization (aCGH) and in addition attempt to correlate CNAs with modified gene expression. MATERIALS AND METHODS: Genome-wide screening was performed on 15 OSCCs using high-density aCGH. On the basis of pathway analysis, three genes (ISG15, Nestin and WNT11) which mapped to CNA regions were selected for further evaluation of their mRNA expression using quantitative reverse transcriptase PCR (qRT-PCR). RESULTS: Copy number alterations were observed on multiple genomic regions, including amplifications on 1p, 3q, 5p, 6p, 7p, 8q, 9q, 11q, 12q, 16p, 18p and deletions on 3p, 7q, 8p, 11q, 19q and 20q. Among the three selected genes, ISG15 had the highest mRNA expression level with a 22.5-fold increase, followed by Nestin with a 4.5-fold increase and WNT11 with a 2.5-fold increase. CONCLUSIONS: This study has identified several major CNAs in oral cancer genomes and indicated that this correlates with over expression of the ISG15, WNT11, and Nestin genes.

Antioxidant effects of glutathione and IGF in a hyperglycaemic cell culture model of fibroblasts: some actions of advanced glycaemic end products (AGE) and nicotine.

The aim of this investigation was to establish potential oxidative effects of glucose, advanced glycation end products (AGE) and nicotine (N) in a fibroblast cell culture model using the anti-oxidants glutathione (G) and insulin like growth factor (IGF). Assays of androgen metabolites were used as biomarkers of healing in this context. Confluent monolayer cultures of human gingival fibroblasts were established in 24 well multiwell plates and incubated in Eagle's MEM for 24h using two radiolabelled androgen substrates 14C-testosterone/14C-4-androstenedione. The established effective concentrations of G1000, glutathione and AGE were used alone and in combination with nicotine and insulin-like growth factor. The medium was then solvent extracted for steroid metabolites, evaporated to dryness and subjected to thin layer chromatography in a benzene acetone solvent system 4:1 v/v for separation of formed metabolites. The metabolites were quantified, using a radioisotope scanner. Significant reduction in the yields of DHT in response to G1000, AGE and nicotine (n=6; p <0.003) were overcome by glutathione (n=6; p <0.002). The stimulatory effect of IGF when combined with AGE was further enhanced by the antioxidant effect of glutathione (n=6; p <0.003). Glucose, AGE and nicotine had a significant inhibitory effect on the yields of the androgen biomarker DHT, overcome by the antioxidant glutathione and IGF, suggestive of an oxidant role for the former agents and an anti-oxidant one for the latter. These agents affected yields of androgen metabolites, biomarkers of oxidative stress and repair, with potential implications on healing in uncontrolled diabetic smokers.

Malignant rhabdoid tumour of the brain.

Rhabdoid tumour is a rare childhood tumour with poor prognosis. We report a 13-month-old Malay girl suffering from this tumour that was located at the left fronto-temporo-parietal region of the brain. Computed tomography showed a large irregular enhancing mass that caused obstructive hydrocephalus. The tumour did not reduce in size after three operations and finally the patient succumbed to the disease four months after diagnosis.

A comparative study of sevoflurane sedation with nitrous oxide sedation for dental surgery.

This study compares the use of inhalation sedation using sevoflurane (group S) with inhalation sedation using nitrous oxide (group N) in patients undergoing bilateral extraction of third molar teeth under local anaesthesia. The study was designed as a cross-over study. Seventeen ASA I, day surgery patients were studied. Patients were randomly allocated to receive either 8 l/min 50% nitrous oxide in oxygen (group N) or same flow of 1% sevoflurane (group S) for the first procedure. Each patient then had the alternate method of sedation for the second procedure. There were no significant differences between the methods in patient co-operation and surgeon's satisfaction with sedation. Psychomotor tests were comparable in both groups. The patients were significantly more sedated in the group S compared to group N (P=0.004). Significantly more patients complained of an unpleasant odour group S (P<0.01) but none withdrew from the study for this reason. No adverse cardiorespiratory effects resulted from sevoflurane or nitrous oxide sedation. Both methods gave good amnesia during the procedure. There was high acceptance of both methods and the patients rated the technique as equally satisfactory. We conclude that inhalation sedation with sevoflurane is a suitable alternative method to nitrous oxide sedation.

Gliricidia (Gliricidia sepium) Green manures as a potential source of N for maize production in the tropics.

Use of cheap, N-rich, and environmentally benign legume green manures to correct N deficiency in infertile soils is a very attractive option in the humid tropics. Understanding the influence of management and climate on their effectiveness, and quantifying their contribution to crop productivity, is therefore crucial for technology adoption and adaptation. Mineral N buildup and the contribution to N uptake in maize were studied in an Ultisol amended with fresh Gliricidia leaves. Net mineral N accumulation was compared in mulched and incorporated treatments in a field incubation study. The 15 N isotope dilution technique was used to quantify N supplied to maize by Gliricidia leaves in an alley cropping. Mineral N accumulation was slow, but was much greater after incorporation than after mulching. Also, N buildup was always higher in the topsoil (0 to 10 cm) than in the subsoil (10 to 20 cm). More NO3-N was leached than NH4-N, and the effect was greater in the incorporated treatment. Surface-applied Gliricidia leaves significantly increased N uptake by maize, and supplied >30% of the total N in the stover and >20% of that in the corn grain, even in the presence of hedgerows. Thus Gliricidia leaf mulch has immense potential to improve productivity in tropical soils.

Immunohistochemical characterization of T-lymphocytes subsets in Egyptian hepatic schistosomiasis.

Liver biopsies from 20 schistosomal patients in the compensated stage were studied by immunoalkaline phosphatase technique for the relative distribution of T-cell subpopulations. T-cell subsets were defined for OKT3 (+) (pan T-lymphocytes), OKT4 (+) (helper-inducer), and OKT8 (+) (suppressor-cytotoxic) cell by using mouse hybridoma monoclonal antibodies. Sections showed marked pan T-lymphocytic infiltration predominantly in the portal tract within liver lobules and in the granulomatous lesions. Marked relative increment of suppressor/cytotoxic OKT8 (+) lymphocytes over the helper/inducer OKT4 (+) were observed. Alkaline phosphatase activity showed inverse significant correlation with OKT3 (+) and OKT8 (+) % and a direct significant correlation with OKT4 (+) % lymphocytes. This may suggest that suppressor cytotoxic OKT8 lymphocytes may be responsible for the modulation of the granulomata and stabilization of the morbidity state.

Corneal vital staining with gentian violet.

We have used 0.5% gentian violet solution as a corneal vital stain in 112 patients with variable degrees of corneal involvements and in 40 normal eyes as control. Gentian violet stained the epithelial defects and degenerated epithelial cells of cornea. The stain persisted 3-5 minutes and disappeared by 8-10 minutes. There was no cross infection from dye use. The dye did not hamper usual process of repair of corneal lesions. It is found highly feasible, with a sensitivity about 100% and specificity about 95%, with some minor side effects. Thus it could be an excellent method in community ophthalmology for early diagnosis of corneal affections, thereby commencing prompt and appropriate treatment in early stage.

Human fascioliasis: T cell subsets in liver before and after bithionol treatment.

Liver biopsies from 5 patients with established fascioliasis, before and after bithionol treatment were studied by immunoalkaline phosphatase technique for relative distribution of T cells and their subpopulations. T cell and its subsets are defined for OKT3+ (pan T), OKT4+ (helper/inducer) and OKT8+ (suppressor/cytotoxic) cells by using mouse monoclonal antibodies. Before bithionol treatment, lymphocytic infiltration in all hepatic lesions were predominantly of OKT3+ (pan T) lymphocytes. The distribution of OKT8+ cells was moderate to severe in comparison to the few OKT4+ cells presentation. After bithionol a noticeable regression of the OKT3 lymphocytic in all liver sections. The majority of the lymphocytic infiltration was of the OKT8+ cells, in comparison to the absence of the OKT4+ ones. This may indicate that suppressor/cytotoxic lymphocytes may have a role in the immune regulation of the disease and the mode of action of bithionol is by the accentuation of this immunoregulatory effect.