Bilateral Tibial Tuberosity Periosteal Sleeve Fracture in an Adolescent: A Case Report

Tibial tuberosity avulsion fracture is a rare injury, and bilateral occurrence is more uncommon. Periosteal sleeve fracture is a unique fracture pattern which was first described in the lower pole of patella in children. We are reporting a rare case of bilateral tibial tuberosity sleeve fracture in a teenage boy which occurred while sprinting. The patient underwent open reduction, pull through suture fixation of the bilateral tibial tuberosity and screw fixation of left tibial tuberosity. Post-operative rehabilitation included gradual increment of range of motion with hinged brace and quadriceps muscle strengthening. Close follow-up was done to monitor the progression of his recovery. At six months follow-up, the patient recovered well. Both knees had full range of motion with an intact extensor mechanism.

Oral Verruciform Xanthoma of lateral border of tongue - a sheep in wolf's clothing

Oral Verruciform Xanthoma (OVX) is an uncommon benign lesion of the oral cavity. Most authors consider it to develop as a response to chronic local irritation. It usually presents as a pink, yellow or greyish flat mass occurring on the gingiva, alveolar ridge or hard palate. This paper reports to you the management of a case of Oral Verruciform Xanthoma occurring on the latero-ventral border of the tongue in a young male patient, which is a rare location for this lesion. It goes on to discuss the etiopathogenesis and clinical features of this rare lesion and emphasizes the importance of having a broad knowledge of oral pathologic lesions especially for lesions that resemble malignant or pre-malignant pathologies in the oral cavity.

Conversion of palatal rugae pattern to scanable Quick Response code in an Arabian population

Backgroud/purpose

Palatal rugae (PR) are situated in the anterior part of the hard palate and possess unique and stable characteristics that can be used in human identification. Their pattern of orientation is established early in life and remains stable thereafter. The purposes of this study were to convert PRP into alphanumeric codes in order to generate scanable Quick Response (QR) codes, to demonstrate uniqueness of PRP using the codes in the study population, and to determine the sexual dimorphism of PRP in the study population.

Materials and methods

Orthodontic dental casts of 256 Saudi male and female patients were photographed after ensuring standardization. Individual rugae characteristics, strength and their displacement from incisive papilla and midpalatine raphe were recorded in the form of an alphanumeric code which was subsequently converted to a QR code. Computer assisted check was performed for possible match in the 256 alpha numeric codes while QR codes were scanned using a bar code scanner to determine uniqueness. Sexual dimorphism of palatal rugae (PR) was also analysed.

Results

All alphanumeric codes of the study population were unique. Mean number of PR in males and females differed significantly (P = 0.0001). Differences in rugae characteristics and strengths in males and females were also present.

Conclusion

The alphanumeric and QR code of the rugae pattern are unique for each individual and can be used for digital record keeping and person identification. A high degree of sexual dimorphism in PR exists in the studied Arab population studied.

Oral rehabilitation of Parkinson's disease patient: a review and case report

Parkinson's disease is usually seen in adults in their middle and late ages. Most people with this disease are less likely to opt for dental treatments unless it is an acute condition. Tremors caused by Parkinson's disease can make dental appointments, especially prolonged treatments, a challenge. The case presented here was successfully treated with an immediate denture for the partially edentulous maxillary and mandibular arches. Early morning brief appointments were given for the procedure. Patient was instructed to take the prescribed parkinsonism medications 60 to 90 minutes before the appointment to utilize the advantage of its peak response. Sympathetic and caring approach towards the patient was employed to reduce his anxiety during the procedures. Some modification of technics and materials was adopted to suit the special situation.

Radiation risk assessment in professionals working in dental radiology area using buccal micronucleus cytome assay

OBJECTIVE

The aim of this study was to assess the incidence of micronuclei (MN) in buccal mucosal cells of professionals working in radiology area to determine the risk of stochastic effects of radiation.

MATERIALS AND METHODS

All the professionals and students working in King Khalid University - College of Dentistry radiology area were included in the Risk Group (RG = 27). The Control Group (CG = 27) comprised of healthy individual matching the gender and age of the RG. Buccal mucosal scraping from all the 54 subjects of RG and CG were stained with Papanicolaou stain and observed under oil immersion lens (×100) for the presence of micronuclei (MN) in the exfoliated epithelial cells.

RESULTS

There was no significant difference between the incidence of MN in RG and CG (p = >0.05) using t-test.

CONCLUSION

Routine radiation protection protocol does minimize the risk of radiation induced cytotoxicity, however, screening of professionals should be carried out at regular intervals.

Age estimation using third molar teeth: A study on southern Saudi population

OBJECTIVE

To estimate the age of an individual between 13 and 23 years, using Demirjian method in Saudi male patients in the southern region of the Kingdom of Saudi Arabia.

MATERIALS AND METHODS

A total of 360 male patient's digital panoramic radiographs were used to evaluate the morphology of mandibular 3rd molar teeth roots according to the Demirjian method. Using descriptive statistical method, age was calculated.

RESULTS

Result showed a strong relation of age with stages of root development of 3rd molar teeth. The standard deviation of mean of root development stages is 1.47 years of age.

CONCLUSION

This study suggests that age can be predicted with a statistical significant result for ages between 13 and 23. Further studies with large population are needed for better statistical results and for female age assessment.

Training workshops in problem-based learning: changing faculty attitudes and perceptions in a Pakistani medical college

BACKGROUND

Problem-based learning (PBL) has over the years become a learning strategy established for teaching students in medicine. In order to use PBL as a teaching tool, faculty must be familiar with PBL and comfortable with the role transition from 'teacher' to 'facilitator'. This transition is critical for the success of PBL. This article describes the faculty development process undertaken in Pakistan at the onset of introduction of PBL in the curriculum.

METHODS

At the Foundation University Medical College (FUMC), we initiated a faculty development program in PBL. The program consisted of two-day, hands-on facilitator training workshops conducted five times over the year and led by in-house faculty. A total of 180 faculty members completed these workshops. The workshops consisted of interactive sessions on the philosophy of PBL, small group dynamics, the role of the facilitator, an introduction to case design, wrap-up PBL sessions and assessment in PBL. Participants were provided with pre-workshop reading material in the form of 'PBL Handbooks', which contained details of the PBL process and specific responsibilities of the facilitator. Participants were also given a chance to experience the role of the facilitator by facilitating the faculty-learner group through a PBL session and receiving feedback. A retrospective pre-post survey was conducted to gauge changes in participants' perceptions of PBL.

RESULTS

The faculty reported a significant increase in their regard for PBL as an instructional paradigm (p=<0.001). They also generally became more interested in empowering students with self-directed learning using PBL as a teaching tool and showed a greater desire to be facilitators (p=<0.001).

CONCLUSION

This evaluation reveals that facilitator training workshops can help not just to improve the facilitation skills of participants but also to stimulate interest amongst faculty to use PBL in the curriculum. Such workshops can be run in Pakistan at minimal cost: the only cost we incurred was for photocopying the reading material. How much difficulty the faculty will actually have serving as facilitator in the PBL process will only become evident when they lead PBL groups over the coming year.

Epithelioid hemangioendothelioma of the liver

Epithelioid hemangioendothelioma is an intermediate grade malignant neoplasm of vascular origin. The tumor involves the liver and lungs, but other organs are affected too. The key to the diagnosis is identification of cells of endothelial origin containing Factor VIII R antigen. Surgical resection of isolated lesions is the treatment of choice; with unpredictable results reported for chemotherapy, radiotherapy, and resection of multiple lesions. The prognosis is very variable, and ranges from few months to more than 25 years.

Antigen-specific T cell tolerance down-regulates mast cell responses in vivo

Fel d I is the major cat allergen that induces asthma and allergic rhinitis in humans. To investigate the mechanism of allergic responses to this allergen, a mouse model was developed. Mice sensitized to chain 1 of Fel d I exhibited T cell responses, B cell responses, and mast cell responses when challenged with the protein. Subcutaneous injections of peptides containing the dominant T cell epitopes of the allergen induced T cell tolerance in presensitized mice. When challenged with the allergen intratracheally, these tolerized mice produced a decreased amount of histamine in vivo. The decrease in histamine release was not solely dependent on the reduction of allergen-specific IgE. These data show that mast cell activity in mice with an ongoing sensitivity to allergen can be regulated through peptide-induced T cell tolerance.

Bolus injection of aqueous antigen leads to a high density of T-cell-receptor ligand in the spleen, transient T-cell activation and anergy induction

In vivo anergy can be modelled by administration of soluble peptide to T-cell receptor (TCR) transgenic mice specific for the moth cytochrome c peptide 88-103 (MCCp). Two weeks after initial peptide treatment, T cells were present in normal numbers but were unresponsive to antigen stimulation in vitro. Only bolus injections of peptide, either subcutaneous or intravenous, were effective at inducing tolerance, while slowly released antigen administered via mini-osmotic pump failed to result in anergy. Examination of T cells soon after bolus peptide administration revealed that anergy induction was preceded by a transient hyperactivation of T cells in vivo. Within 2 hr of peptide treatment, interleukin-2 was detectable in the plasma of the transgenic mice. Interestingly, only bolus injections of peptide led to high levels of T-cell activation, while adjuvant emulsified and pump-administered peptide resulted in very low stimulation in vivo. When the dose of bolus-injected peptide used for tolerization was titrated, the extent of anergy induction directly correlated with the intensity of early T-cell activation. Indirect measurements of TCR-ligand density on the surface of antigen-presenting cells following peptide administration revealed that aqueous peptide delivered via bolus injection generated a large number of major histocompatibility complex-peptide complexes, while pump-delivered and adjuvant-emulsified peptide did not. These data suggest that high levels of TCR ligand are required for in vivo T-cell hyperactivation and induction of anergy.

IL-4 production by allergen-stimulated primary cultures: identification of basophils as the major IL-4-producing cell type

As a potent inducing agent for IgE production and differentiation factor for allergen-specific Th2 cells, IL-4 is a key regulatory cytokine both in the pathogenesis of allergic disease and in the ongoing allergic response. The assay of in vitro IL-4 production has often been used to compare the allergen responses of T cells isolated from atopic and non-atopic subjects. Because peripheral blood basophils also have the capacity to respond to specific allergen by producing IL-4, we investigated the relative contribution of these two cell types to IL-4 production in allergen-stimulated primary cultures. Among unfractionated peripheral blood mononuclear cells (PBMC), the major producers of detectable IL-4 in primary in vitro cultures were found to be basophils based on: (i) an allergen dose-response corresponding closely to that required for basophil histamine release and lower than that required for T cell activation; (ii) a rapid time course for IL-4 production (detectable at 3 h), inconsistent with the typical activation requirements of fresh T cells; (iii) the production of comparable levels of IL-4 in cultures stimulated with allergen or anti-IgE; and (iv) the complete loss of detectable IL-4 production following specific depletion of basophils from PBMC. The T cells in these cultures were functionally able to produce IL-4, as demonstrated by mitogen activation of basophil-depleted PBMC. These findings demonstrate that although IL-4 production in primary in vitro cultures can be used as a sensitive indicator of allergen responsiveness, the accurate interpretation of this result requires identification of the responding cell type. Furthermore, these findings raise the possibility that basophil production of IL-4 early in the course of allergen stimulation may shape subsequent T cell responses both in vivo and in vitro.

Peripheral tolerance in T cell receptor-transgenic mice: evidence for T cell anergy

T cell tolerance can be induced in adult mice by injection of soluble antigenic peptide. The underlying mechanism has been difficult to establish in normal mice due to the low precursor frequency of T cells specific for any given antigen. Therefore, we examined peripheral tolerance in mice transgenic for a T cell receptor specific for a cytochrome c peptide bound to I-Ek. Antigen-specific hyporesponsiveness could be induced in the transgenic mice. We followed the transgene-bearing T cells with a clonotypic monoclonal antibody and found similar numbers of clonotypic T cells in tolerized and control mice. To prevent de novo differentiation of T cells we analyzed thymectomized mice in which antigen-specific hyporesponsiveness was induced. Our analysis of thymectomized transgenic mice showed that antigen-specific T cell hyporesponsiveness following injection of peptide intravenously is not caused by gross elimination of T cells. These data provide evidence for the role of anergy in peripheral tolerance.

Control of memory CD4 T cell activation: MHC class II molecules on APCs and CD4 ligation inhibit memory but not naive CD4 T cells

Memory or antigen-experienced CD4 T cells differ from naive CD4 T cells both phenotypically by cell surface marker expression, and functionally by their dissimilar pattern of cytokine secretion and activation requirements through their T cell receptor (TCR). We show here that activation of memory CD4 T cells (CD45RBlo subset), but not naive CD4 T cells (CD45RBhi subset), is inhibited by MHC class II molecules on antigen-presenting cells and by CD4 ligation. We propose that the selective negative signal in memory cells is a direct result of the differences in signaling via CD4 and CD3, exemplified in the disparate pattern of tyrosine-phosphorylated proteins visible after activation of the two subsets. In vivo, this inhibitory signal may serve to prevent irrelevant interactions between memory CD4 T cells and bystander MHC class II+ cells, and may also be responsible for the defective functioning of memory CD4 T cells in AIDS.

Activation requirements for CD4+ T cells differing in CD45R expression

Murine CD4+ T cells can be subdivided into naive and memory T cells based on surface phenotype, on recall response to Ag, and on differences in activation requirements. Furthermore, several studies have shown that two signals are required for CD4+ T cell activation; one signal is provided by occupancy of the TCR and the other signal is provided by the APC. In this report, analysis of naive and memory CD4 T cells, separated on the basis of CD45 isoform expression, has shown that their requirements for two signals differ. Activation of memory CD4 T cells to proliferate and secrete IL-2/IL-4 only required occupancy of the TCR complex, whereas activation of naive CD4 T cells required an APC-derived signal as well. Moreover, the signal induced by anti-CD3 antibodies differs from the signal provided by anti-V beta cross-linking of the TCR because both antibodies activate memory CD4 T cells but only anti-CD3 activates naive CD4 T cells. Together these data suggest that the consequence of stimulation through the TCR/CD3 signal complex differs between memory and naive CD4 T cells.

Activation requirements for CD4+ T cells differing in CD45R expression

Murine CD4+ T cells can be subdivided into naive and memory T cells based on surface phenotype, on recall response to Ag, and on differences in activation requirements. Furthermore, several studies have shown that two signals are required for CD4+ T cell activation; one signal is provided by occupancy of the TCR and the other signal is provided by the APC. In this report, analysis of naive and memory CD4 T cells, separated on the basis of CD45 isoform expression, has shown that their requirements for two signals differ. Activation of memory CD4 T cells to proliferate and secrete IL-2/IL-4 only required occupancy of the TCR complex, whereas activation of naive CD4 T cells required an APC-derived signal as well. Moreover, the signal induced by anti-CD3 antibodies differs from the signal provided by anti-V beta cross-linking of the TCR because both antibodies activate memory CD4 T cells but only anti-CD3 activates naive CD4 T cells. Together these data suggest that the consequence of stimulation through the TCR/CD3 signal complex differs between memory and naive CD4 T cells.

Hepatitis C as a cause of chronic liver disease in northern Pakistan

The antibodies to hepatitis C virus (HCV) were tested in 45 histologically confirmed cases of chronic liver disease. Twelve cases had chronic hepatitis, 24 cirrhosis and 9 hepatocellular carcinoma. Anti-HCV was detected in 6 patients. Two (16.67%) were suffering from chronic hepatitis, 3 (12.5%) had cirrhosis and one (11.11%) hepatocellular carcinoma. None of the anti-HCV positive cases had past history of blood transfusion. The patients of chronic liver disease in this study had a much higher prevalence of HBV infection which indicates that in northern Pakistan hepatitis C virus infection is not a common cause of chronic liver disease whereas HBV infection plays an aetiological role in a much larger number of these cases.

Differential effect of interleukin 1 on naive and memory CD4+ T cells

Freshly derived murine CD4+ T cells are divided into naive and memory cells based on the expression of CD45 isoforms. Cross-linking the T cell receptor CD3 complex either by plastic-bound anti-CD3 antibodies or the antibody presented on non-lymphoid Fc gamma receptor type II-positive Chinese hamster ovary cells in absence of competent antigen-presenting cells fails to activate naive cells to either secrete cytokines or to proliferate. In contrast, memory cells secrete their characteristic cytokines [interleukin (IL) 2, IL4, and interferon-gamma] and show significant proliferation to this stimulus. IL 1 however, is required for their optimal clonal expansion. Differential expression of IL 1 receptor mRNA in memory cells also correlate with their responsiveness to IL 1. Thus, these data reveal a basic difference in the requirements for activation of naive and memory CD4+ T cells.

Differential expression of the alternatively spliced exons of murine CD45 in Th1 and Th2 cell clones

Antigen-specific murine CD4+ T cell clones can be divided into functionally distinct subsets known as Th1 and Th2. To date these cells have been indistinguishable by surface phenotype. This report identifies two anti-CD45R monoclonal antibodies (14.8 and C363.16A) that bind preferentially to Th2 cells. Further analysis of the CD45-specific mRNA in Th1 and Th2 cells shows clear differences between these two cell types. Th1 cell clones express mRNA for the two smallest forms of CD45 containing none or only one of the alternatively splices exons. In contrast, Th2 cell clones express predominantly the high molecular weight isoforms of CD45 containing two or three of the alternatively spliced exons.

Molecular associations on the T cell surface correlate with immunological memory

Different isoforms of CD45 are expressed on naive and memory CD4 T cells in the mouse, as revealed by an antibody to a set of isoforms of CD45 that utilize exon B, called CD45RB. Cloned TH1 and TH2 lines also differ for expression of isoforms detected by this antibody. Differential expression of CD45 isoforms correlates with different behavior of cell surface molecules involved in transmembrane signal transduction. On naive T cells, CD4, CD45 and the CD3/T cell receptor complex behave as independent entities. On memory T cells, these three molecules are stably associated on the T cell surface. Furthermore, on TH2 cells, which express intermediate levels of CD45RB, CD4 is stably associated with CD45 isoforms other than CD45RB, but this complex is not associated with the CD3/T cell receptor. These results lead us to propose that immunological memory in CD4 T cells consists of an altered structure of the T cell's specific signal transduction apparatus controlled by low-molecular weight CD45 isoforms. This altered receptor structure would allow the more sensitive triggering of the T cell characteristic of memory cells. The organization of multimolecular signal transduction systems may be a general means by which cells alter their physiological behavior, allowing the acquisition of new phenotypic characteristics.

The use of ORS (Nimkol) in management of childhood diarrhoea by mothers in the suburbs of Rawalpindi-Islamabad

A total of 595 respondents (200 from urban Kachi-abadis and 395 from rural communities of Rawalpindi-Islamabad) were interviewed for their knowledge about the use of ORS (Nimkol) in childhood diarrhoea. Most of the respondents were mothers with low literacy rate (23%). The prevalence of current diarrhoea among children was 36.8% on the day of interview whereas 57% of the children had history of having suffered from an episode of diarrhoea during the past two weeks. About 75% respondents claimed that they had an experience of using ORS (Nimkol). Most of them (72.1%) had used ORS (Nimkol) for childhood diarrhoea and dehydration and 28% had used it for diseases other than childhood diarrhoea or on doctor's advice. Only 11% mothers of children who were currently suffering from diarrhoea were using ORS (Nimkol) and a few mothers mentioned of giving home made fluid remedies like salt-water, salt-sugar-water or lemon-sugar-salt water for childhood diarrhoea. The use of ORS (Nimkol) was more common among the families with higher income. Regarding the preparation of ORS (Nimkol) solution, 57.8% respondents had fairly accurate knowledge. Fifty percent of the respondents had procured ORS (Nimkol) from the hospitals or clinics.

A monoclonal antibody to murine CD45R distinguishes CD4 T cell populations that produce different cytokines

CD4 T cell clones have been shown to be functionally heterogeneous in the mouse. However, it is not known if normal CD4 T cells are also functionally heterogeneous, or whether functional specialization is a result of cloning and long-term culture. To approach this question, a monoclonal antibody reacting with a subset of CD4 T cells has been prepared by immunization of rats with different cloned T cell lines all sharing the same functional activity. This monoclonal antibody reacts with a subset of CD45 (T200) molecules by binding to a determinant requiring the expression of the second variable exon of the CD45 molecule. Some CD4 T cells bear high levels of this marker, while others react only weakly. This antibody was used to separate CD4 T cells into two subpopulations. The brightly staining population was found to produce interleukin (IL) 2 and not IL 4, while the weakly staining population produced IL 4 and not IL 2. These data demonstrate that CD4 T cells in normal mice are already functionally committed, and that they differentially express forms of CD45 that contain the second variable exon.

Epidemics of non-A, non-B hepatitis in Pakistan

Three epidemics of acute viral hepatitis which occurred in different areas of Pakistan, namely Quetta, Mardan and Rawalpindi were studied. All the cases presented with jaundice, anorexia and nausea. The liver function tests showed raised serum bilirubin, alkaline phosphatase and ALT levels. In all the patients except one, the serology was consistent with non-A, non-B (NANB) hepatitis, which was most likely waterborne. This study shows that, as in some other parts of Asia and North Africa, epidemics of waterborne NANB hepatitis, clinically resembling hepatitis A, also occur in Pakistan. These epidemics are probably due to faecal contamination of the water supply systems in some areas of Pakistan.