ABSTRACT
We seldom apply rigorous methods to how scientists think as they make new discoveries and open new avenues of inquiry. The progress of science relies on one generation of scientists transferring their thought processes and methods to the next. In a culture of inquiry, respect, rigor, and role modeling, critical thinking can thrive as novices become accomplished scientists. Although scientists are typically judged on the basis of results (publication, symposium, etc.) rather than the thought process used to get that result, the thought process is of paramount importance for training the next generation of scientists. As a profession pays closer attention to the educational process whereby novices become accomplished scientists, a wider discussion of how accomplished scientists think is vital to help novice scientists positively advance through the early vulnerable years. Thinking critically about our goals and values-including the value of emulation, experience, biases, and doubt-is a necessary part of that process.
Subject(s)
Physicians , Thinking , HumansABSTRACT
OBJECTIVES: To identify the molecular etiology of distinct dental anomalies found in eight Thai patients and explore the mutational effects on cellular functions. MATERIALS AND METHODS: Clinical and radiographic examinations were performed for eight patients. Whole exome sequencing, mutant protein modelling, qPCR, western blot analysis, scratch assays, immunofluorescence, confocal analysis, in situ hybridization, and scanning electron micrography of teeth were done. RESULTS: All patients had molars with multiple supernumerary cusps, single-cusped premolars, and a reduction in root number. Mutation analysis highlighted a heterozygous c.865A>G; p.Ile289Val mutation in CACNA1S in the patients. CACNA1S is a component of the slowly inactivating L-type voltage-dependent calcium channel. Mutant protein modeling suggested that the mutation might allow leakage of Ca2+ or other cations, or a tightening, to restrict calcium flow. Immunohistochemistry analysis showed expression of Cacna1s in the developing murine tooth epithelium during stages of crown and root morphogenesis. In cell culture, the mutation resulted in abnormal cell migration of transfected CHO cells compared to wildtype CACNA1S, with changes to the cytoskeleton and markers of focal adhesion. CONCLUSIONS: The malformations observed in our patients suggest a role for calcium signaling in organization of both cusps and roots, affecting cell dynamics within the dental epithelium.
ABSTRACT
Risk loci identified through genome-wide association studies have explained about 25% of the phenotypic variations in nonsyndromic orofacial clefts (nsOFCs) on the liability scale. Despite the notable sex differences in the incidences of the different cleft types, investigation of loci for sex-specific effects has been understudied. To explore the sex-specific effects in genetic etiology of nsOFCs, we conducted a genome-wide gene × sex (GxSex) interaction study in a sub-Saharan African orofacial cleft cohort. The sample included 1,019 nonsyndromic orofacial cleft cases (814 cleft lip with or without cleft palate and 205 cleft palate only) and 2,159 controls recruited from 3 sites (Ethiopia, Ghana, and Nigeria). An additive logistic model was used to examine the joint effects of the genotype and GxSex interaction. Furthermore, we examined loci with suggestive significance (P < 1E-5) in the additive model for the effect of the GxSex interaction only. We identified a novel risk locus on chromosome 8p22 with genome-wide significant joint and GxSex interaction effects (rs2720555, p2df = 1.16E-08, pGxSex = 1.49E-09, odds ratio [OR] = 0.44, 95% CI = 0.34 to 0.57). For males, the risk of cleft lip with or without cleft palate at this locus decreases with additional copies of the minor allele (p < 0.0001, OR = 0.60, 95% CI = 0.48 to 0.74), but the effect is reversed for females (p = 0.0004, OR = 1.36, 95% CI = 1.15 to 1.60). We replicated the female-specific effect of this locus in an independent cohort (p = 0.037, OR = 1.30, 95% CI = 1.02 to 1.65), but no significant effect was found for the males (p = 0.29, OR = 0.86, 95% CI = 0.65 to 1.14). This locus is in topologically associating domain with craniofacially expressed and enriched genes during embryonic development. Rare coding mutations of some of these genes were identified in nsOFC cohorts through whole exome sequencing analysis. Our study is additional proof that genome-wide GxSex interaction analysis provides an opportunity for novel findings of loci and genes that contribute to the risk of nsOFCs.
Subject(s)
Cleft Lip , Cleft Palate , Cleft Lip/genetics , Cleft Palate/genetics , Female , Genetic Predisposition to Disease/genetics , Genome-Wide Association Study , Humans , Male , Polymorphism, Single Nucleotide/geneticsABSTRACT
INTRODUCTION: Malnutrition in children is one of the most prevalent global health challenges, and malnourished children have a higher risk of death from childhood diseases. Early childhood caries (ECC) is the most common chronic disease of childhood. Complications from ECC such as pain, loss of tooth/teeth, and infection can undermine a child's nutrition and growth. AIM: This study aims to evaluate the severity of decay, missing, and filled tooth (dmft) by nutritional status using the z scores of the anthropometric measurements: height for age (HFA), weight for age (WFA), weight for height (WFH), and body mass index for age (BMIA) among children with ECC in Nigeria. STUDY DESIGN: This is a cross-sectional study conducted in 5 local government areas (LGAs) in Lagos State, Nigeria. A multistage sampling technique was used. RESULTS: A total of 273 cases of ECC were included in the analyses (mean age 4.19 ± 0.96 y). Overall, the mean dmft was 3.04 ± 2.28, and most (96%) were accounted for by untreated decay. The distribution of dmft within the different z score categories of BMIA (<-3 = severely wasted, -2 to -3 = wasted, -2 to +2 = normal, +2 to +3 = overweight and >+3 = obese) showed the highest dmft scores among the combined severely wasted and wasted groups, lowest among children with normal z scores, and intermediate in the overweight and obese groups. There was a significant negative correlation between BMIA z score, WFH z score, and dmft (r = -0.181, P < 0.05 and r = -0.143, P < 0.05, respectively). However, the correlations between HFA z score, WFA z score, and dmft were positive but not significant (r = 0.048, P = 0.44 and r = 0.022, P = 0.77, respectively). CONCLUSION: Our study showed an increased severity of dental caries among severely wasted or wasted children with ECC compared to those of normal or overweight. KNOWLEDGE TRANSFER STATEMENT: The results from this study will raise awareness among clinicians and policy makers on the need for a primary prevention program for early childhood caries in countries with high burden of malnutrition and limited resources. Also, it will help draw the attention of clinicians to the caries status of malnourished children that can be managed to improve the nutritional outcomes.
Subject(s)
Child Nutrition Disorders , Dental Caries , Child, Preschool , Cross-Sectional Studies , Dental Caries/epidemiology , Humans , Nigeria/epidemiology , Nutritional Status , Obesity , OverweightABSTRACT
BACKGROUND: Many studies have investigated the burden of odontogenic tumor (OT) in Nigeria; however, the true burden and prevalence of these lesions are not known because these studies are based on a center/region. AIMS: Hence, the aim of this study is to evaluate the true burden of OTs in Nigeria, using a multicenter approach. MATERIALS AND METHODS: This is a 10-year retrospective cross-sectional study of OT seen in eight tertiary health institutions in different geographic locations in Nigeria. RESULTS: A total of 990 cases were included in this study. The highest prevalence of OT was in the third decade of life (n = 274, 27.7%). Most lesions were benign (n = 961, 97.1%), with a slight male preponderance; and the mandible was the commonest site (n = 814, 82.2%). There were a significant association between the diagnosed OTs and the age group and site (P = 0.002 and 0.031, respectively). CONCLUSION: OTs showed a slightly higher preponderance in males, occurring mostly in the third decade. Benign lesions were frequent and ameloblastoma was the commonest OT. Variations exist in the occurrence of OTs from the different geographic locations in Nigeria. This study essentially sheds a broader light on the clinicopathological distribution of OTs across Nigeria, using a large multicenter approach.
Subject(s)
Odontogenic Tumors , Pathology, Oral , Cross-Sectional Studies , Humans , Male , Nigeria/epidemiology , Odontogenic Tumors/epidemiology , Retrospective StudiesABSTRACT
In contrast to the progress that has been made toward understanding the genetic etiology of cleft lip with or without cleft palate, relatively little is known about the genetic etiology for cleft palate only (CPO). A common coding variant of grainyhead like transcription factor 3 ( GRHL3) was recently shown to be associated with risk for CPO in Europeans. Mutations in this gene were also reported in families with Van der Woude syndrome. To identify rare mutations in GRHL3 that might explain the missing heritability for CPO, we sequenced GRHL3 in cases of CPO from Africa. We recruited participants from Ghana, Ethiopia, and Nigeria. This cohort included case-parent trios, cases and other family members, as well as controls. We sequenced exons of this gene in DNA from a total of 134 nonsyndromic cases. When possible, we sequenced them in parents to identify de novo mutations. Five novel mutations were identified: 2 missense (c.497C>A; p.Pro166His and c.1229A>G; p.Asp410Gly), 1 splice site (c.1282A>C p.Ser428Arg), 1 frameshift (c.470delC; p.Gly158Alafster55), and 1 nonsense (c.1677C>A; p.Tyr559Ter). These mutations were absent from 270 sequenced controls and from all public exome and whole genome databases, including the 1000 Genomes database (which includes data from Africa). However, 4 of the 5 mutations were present in unaffected mothers, indicating that their penetrance is incomplete. Interestingly, 1 mutation damaged a predicted sumoylation site, and another disrupted a predicted CK1 phosphorylation site. Overexpression assays in zebrafish and reporter assays in vitro indicated that 4 variants were functionally null or hypomorphic, while 1 was dominant negative. This study provides evidence that, as in Caucasian populations, mutations in GRHL3 contribute to the risk of nonsyndromic CPO in the African population.
Subject(s)
Black People/genetics , Cleft Palate/genetics , DNA-Binding Proteins/genetics , Loss of Function Mutation/genetics , Transcription Factors/genetics , Animals , Codon, Nonsense/genetics , Frameshift Mutation/genetics , Genome-Wide Association Study , Humans , Mutagenesis, Site-Directed , Mutation, Missense/genetics , RNA Splice Sites/genetics , Zebrafish/embryology , Zebrafish/geneticsABSTRACT
Orofacial clefts (OFCs) are congenital dysmorphologies of the human face and oral cavity, with a global incidence of 1 per 700 live births. These anomalies exhibit a multifactorial pattern of inheritance, with genetic and environmental factors both playing crucial roles. Many loci have been implicated in the etiology of nonsyndromic cleft lip with or without cleft palate (NSCL/P) in populations of Asian and European ancestries, through genome-wide association studies and candidate gene studies. However, few populations of African descent have been studied to date. Here, the authors show evidence of an association of some loci with NSCL/P and nonsyndromic cleft palate only (NSCPO) in cohorts from Africa (Ghana, Ethiopia, and Nigeria). The authors genotyped 48 single-nucleotide polymorphisms that were selected from previous genome-wide association studies and candidate gene studies. These markers were successfully genotyped on 701 NSCL/P and 163 NSCPO cases, 1,070 unaffected relatives, and 1,078 unrelated controls. The authors also directly sequenced 7 genes in 184 nonsyndromic OFC (NSOFC) cases and 96 controls from Ghana. Population-specific associations were observed in the case-control analyses of the subpopulations, with West African subpopulations (Ghana and Nigeria) showing a similar pattern of associations. In meta-analyses of the case-control cohort, PAX7 (rs742071, P = 5.10 × 10(-3)), 8q24 (rs987525, P = 1.22 × 10(-3)), and VAX1 (rs7078160, P = 0.04) were nominally associated with NSCL/P, and MSX1 (rs115200552, P = 0.01), TULP4 (rs651333, P = 0.04), CRISPLD2 (rs4783099, P = 0.02), and NOG1 (rs17760296, P = 0.04) were nominally associated with NSCPO. Moreover, 7 loci exhibited evidence of threshold overtransmission in NSOFC cases through the transmission disequilibrium test and through analyses of the family-based association for disease traits. Through DNA sequencing, the authors also identified 2 novel, rare, potentially pathogenic variants (p.Asn323Asp and p.Lys426IlefsTer6) in ARHGAP29 In conclusion, the authors have shown evidence for the association of many loci with NSCL/P and NSCPO. To the best of this knowledge, this study is the first to demonstrate any of these association signals in any African population.
Subject(s)
Cleft Lip/genetics , Cleft Palate/genetics , Genetic Predisposition to Disease/genetics , Ethiopia/epidemiology , Female , Genetic Loci/genetics , Genetic Markers/genetics , Genome-Wide Association Study , Ghana/epidemiology , Humans , Male , Nigeria/epidemiology , Polymorphism, Single Nucleotide/genetics , Sequence Analysis, DNAABSTRACT
BACKGROUND: Orofacial clefts (OFCs) are common birth defects that may impose a large burden on the health and psychosocioeconomic well-being of affected individuals and families. This study aims to identify qualitative factors that affect the quality of life (QOL) of family caregivers of children with OFCs. METHODS: A mixed-method study in which family caregivers of OFCs children were consecutively recruited from cleft clinics over a 3-month period. Quantitative data were analyzed using SPSS version 17 and focus group discussion by framework analysis. RESULTS: A total of 107 caregivers participated in the entire study, and 24 caregivers participated in the focus group discussions. About 50% of the children had cleft lip and palate (CLP), 28% with cleft lips only (CL) and 23.4% with cleft palate only (CP). Poor access to specific information and lack of empathy of professionals affected the quality of life and delivery of family-centered care. CONCLUSIONS: To improve the quality of life of family caregivers, individual-focused counseling sessions should be organized for caregivers soon after birth. This will provide an opportunity to discuss the laid out plans for supportive care. It will also be as an avenue to address the arising social issues by health professionals and counselors.
Subject(s)
Caregivers/psychology , Cleft Lip/psychology , Cleft Palate/psychology , Quality of Life , Access to Information/psychology , Adolescent , Adult , Communication , Empathy , Female , Focus Groups , Humans , Infant , Infant, Newborn , Male , Nigeria , Professional-Family Relations , Surveys and Questionnaires , Young AdultABSTRACT
Orofacial clefts are the most common malformations of the head and neck. In Africa, orofacial clefts are underascertained, with little or no surveillance system in most parts for clefts and other birth defects. A Nigerian craniofacial anomalies study, NigeriaCRAN, was established in 2006 to support cleft research specifically for epidemiological studies, treatment outcomes, and studies into etiology and prevention. We pooled data from seven of the largest Smile Train treatment centers in the six geopolitical zones in Nigeria. Data from September 2006 to June 2011 were analyzed and clefts compared between sides and genders using the Fisher exact test. A total of 2197 cases were identified during the study period, with an estimated prevalence rate of 0.5 per 1000. Of the total number of orofacial clefts, 54.4% occur in males and 45.6% in females. There was a significant difference (P = .0001) between unilateral left clefts and unilateral right clefts, and there was a significant difference (P = .0001) between bilateral clefts and clefts on either the left or right side. A significant gender difference (P = .03) was also observed for cleft palate, with more females than males. A total of 103 (4.7%) associated anomalies were identified. There were nine syndromic cleft cases, and 10.4% of the total number of individuals with clefts have an affected relative. The significant difference between unilateral clefts and the gender differences in the proportion of cleft palate only are consistent with the literature. The present study emphasizes the need for birth defects registries in developing countries in order to estimate the exact prevalence of birth defects including orofacial clefts.
Subject(s)
Cleft Lip/epidemiology , Cleft Palate/epidemiology , Female , Humans , Infant, Newborn , Male , Nigeria/epidemiology , Prevalence , RegistriesABSTRACT
BACKGROUND: The central third of the face is distorted by the bilateral cleft of the lip and palate and restoring the normal facial form is one of the primary goals for the reconstructive surgeons. The history of bilateral cleft lip repair has evolved from discarding the premaxilla and prolabium and approximating the lateral lip elements to a definitive lip and primary cleft nasal repair utilising the underlying musculature. The aim of this study was to review surgical outcome of bilateral cleft lip surgery (BCLS) done at the Lagos University Teaching Hospital. MATERIALS AND METHODS: A review of all cases of BCLS done between January 2007 and December 2012 at the Lagos University Teaching Hospital was done. Data analysis included age and sex of patients, type of cleft deformity and type of surgery (primary or secondary) and whether the cleft deformity was syndromic and non-syndromic. Techniques of repair, surgical outcome and complications were also recorded. RESULTS: A total of 39 cases of BCLS involving 21 males and 18 females were done during the period. This constituted 10% (39/390) of all cases of cleft surgery done during the period. There were 5 syndromic and 34 non-syndromic cases. Age of patients at time of surgery ranged between 3 months and 32 years. There were 24 bilateral cleft lip and palate deformities and 15 bilateral cleft lip deformities. Thirty-one of the cases were primary surgery, while 8 were secondary (revision) surgery. The most common surgical technique employed was modified Fork flap (Millard) technique, which was employed in 37 (95%) cases. CONCLUSION: Bilateral cleft lip deformity is a common cleft deformity seen in clinical practice, surgical repair of which can be a challenge to an experienced surgeon. A modified Fork flap technique for repair of bilateral cleft lip is a reliable and versatile technique associated with excellent surgical outcome.
Subject(s)
Cleft Lip/surgery , Lip/surgery , Plastic Surgery Procedures/methods , Surgical Flaps , Child , Child, Preschool , Cleft Lip/epidemiology , Female , Follow-Up Studies , Humans , Incidence , Infant , Male , Nigeria/epidemiology , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: Orofacial clefts are the most common malformations of the head and neck, with a worldwide prevalence of 1 in 700 births. They are commonly divided into CL(P) and CP based on anatomic, genetic, and embryologic findings. A Nigerian craniofacial anomalies study (NigeriaCRAN) was set up in 2006 to investigate the role of gene-environment interaction in the origin of orofacial clefts in Nigeria. SUBJECTS AND METHODS: DNA isolated from saliva from Nigerian probands was used for genotype association studies and direct sequencing of cleft candidate genes: MSX1 , IRF6 , FOXE1, FGFR1 , FGFR2 , BMP4 , MAFB, ABCA4 , PAX7, and VAX1 , and the chromosome 8q region. RESULTS: A missense mutation A34G in MSX1 was observed in nine cases and four HapMap controls. No other apparent causative variations were identified. Deviation from Hardy Weinberg equilibrium (HWE) was observed in these cases (p = .00002). A significant difference was noted between the affected side for unilateral CL (p = .03) and bilateral clefts and between clefts on either side (p = .02). A significant gender difference was also observed for CP (p = .008). CONCLUSIONS: Replication of a mutation previously implicated in other populations suggests a role for the MSX1 A34G variant in the development of CL(P).
Subject(s)
Black People/genetics , Cleft Lip/genetics , Cleft Palate/genetics , MSX1 Transcription Factor/genetics , Mutation, Missense/genetics , Case-Control Studies , Child , Child, Preschool , Cleft Lip/epidemiology , Cleft Palate/epidemiology , Female , Genotype , Humans , Infant , Infant, Newborn , Male , Nigeria/epidemiology , Polymerase Chain Reaction , Sequence Analysis, DNAABSTRACT
This is an overview of the present state of cleft lip and palate care in Nigeria. The aim is to stimulate further discussions on the need to improve standard of care and quality of life in patients with cleft lip and palate deformities. The number of cleft surgeries and surgeons involved in cleft repairs across Nigeria is increasing due to availability of free treatment grants provided by non-governmental organisation; therefore, it has become imperative to assess the quality of surgery and quality of cleft care. It is expected that as the number of repaired cleft lip/palate increases, more patients will require secondary repair, speech therapy, and orthodontics therapy and orthognathic surgery. The following recommendations are made to improve the standard of cleft care in Nigeria: establishment of multidisciplinary team approach, formulation of policy on quality control, establishment of fellowship training in cleft care and establishment of regional specialised cleft care centre.
Subject(s)
Cleft Lip/surgery , Cleft Palate/surgery , Patient Care Team , Quality of Health Care , Humans , Nigeria , Orthognathic Surgical Procedures/standards , Orthognathic Surgical Procedures/trendsABSTRACT
The aim of this study was to investigate the use of information technology amongst dental students, dental nursing students and resident doctors in training at the faculty of dental Surgery University of Lagos. A structured questionnaire was distributed to 58 clinical dental students in 4 th and 5 th years of training in the 2010/2011 academic year, 36 dental nursing students and 63 resident doctors undergoing specialist training. All participants have access to the computers, 2.5% within the University and 31% at home and internet cafes and about 50% have the basic skills required. A significant difference was observed between the resident doctors and clinical dental students (P = 0.003), between resident doctors and dental nursing students (P = 0.0001) when the use of computer for study was compared. Over 95% of participants have access to internet and about 50% of them use the internet for their studies. A significant difference (P = 0.005) was observed between clinical dental students and dental nursing students that use the internet and word processing. The resident doctors used the computers for multimedia and MedLine search tools more than clinical dental students (P = 0.004) and dental nursing students (0.0006). The findings of the study show that dental students and resident doctors in training have the requisite knowledge to operate the computer for use in their study and personal activities.
Subject(s)
Computer Literacy , Computers/statistics & numerical data , Dental Staff, Hospital , Students, Dental , Attitude to Computers , Education, Dental , Female , Humans , Information Storage and Retrieval , Internet , Male , Nigeria , Schools, Dental , Students, Dental/psychology , Students, Dental/statistics & numerical data , Surveys and Questionnaires , TechnologyABSTRACT
BACKGROUND: To carry out a systematic review of the birth prevalence of cleft lip with or without cleft palate (CLP) and cleft palate (CP) in Africa based on available published data. METHOD: Using the Cochrane search strategy and the following keywords words "cleft palate", "prevalence", "incidence", "cleft lip" and "Africa" to screen Ovid Medline {1966 to March 2007), Cinahl {1982-March 2007}, Pub Med, Scopus, and Web-Google. All identified published, prospective and retrospective studies on the birth prevalence of CLP and CP in Africa were included. The dates, location, sources, number of births (live births, still births, number of cleft cases, prevalence rates, sex ratio, cleft types, and clefts with associated anomalies were extracted. RESULTS: Ascertainment of cases was through the hospitals. Overall there were 57 CL/P, 56 CL and 36 CP reported from all the studies. From seven studies combined, 21 males and 20 females had CL, 10 males and 22 females with CP and 26 males and 24 females with CL/P. There were 3 cases with CL/P, 2 with CP and 2 with CL from the three studies that reported clefts with associated anomalies. CONCLUSION: For an improved ascertainment of cleft cases, there is a need to set up a birth defects surveillance system in the form of a national birth registry. Future studies should then aim to include the entire population in geographically defined regions. Reliable data on incidence is an essential pre-requisite for studies into aetiology and prevention.
ABSTRACT
BACKGROUND:To carry out a systematic review of the birth prevalence of cleft lip with or without cleft palate (CLP) and cleft palate (CP) in Africa based on available published data.METHOD:Using the Cochrane search strategy and the following keywords words "cleft palate", "prevalence", "incidence", "cleft lip" and "Africa" to screen Ovid Medline {1966 to March 2007), Cinahl {1982-March 2007}, PubMed, Scopus, and Web-Google. All identified published, prospective and retrospective studies on the birth prevalence of CLP and CP in Africa were included. The dates, location, sources, number of births (live births, still births, number of cleft cases, prevalence rates, sex ratio, cleft types, and clefts with associated anomalies were extracted.RESULTS: Ascertainment of cases was through the hospitals. Overall there were 57 CL/P, 56 CL and 36 CP reported from all the studies. From seven studies combined, 21 males and 20 females had CL, 10 males and 22 females with CP and 26 males and 24 females with CL/P. There were 3 cases with CL/P, 2 with CP and 2 with CL from the three studies that reported clefts with associated anomalies.CONCLUSION: For an improved ascertainment of cleft cases, there is a need to set up a birth defects surveillance system in the form of a national birth registry. Future studies should then aim to include the entire population in geographically defined regions. Reliable data on incidence is an essential pre-requisite for studies into aetiology and prevention