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1.
J Appl Toxicol ; 43(11): 1645-1666, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37340691

RESUMO

The Japanese medaka (Oryzias latipes) extended one-generation reproduction test (MEOGRT) (Test Guideline 890.2200) is a Tier 2 test within the Endocrine Disruptor Screening Program of the US Environmental Protection Agency (US EPA). A modified MEOGRT was used to evaluate multigenerational effects of 2-ethylhexyl 4-hydroxybenzoate (2-EHHB) under flow-through conditions starting with adults (parent generation, F0) through a 3-week reproductive phase of the second generation (F2). Fish were exposed to one of five 2-EHHB test concentrations or a dechlorinated tap water control. Fecundity was affected at the lowest exposure (5.32 µg/L) and greater sensitivity occurred in the F1 and F2 generations. Percent fertility was also diminished from no effect level observed in the F0 generation to 101 and 48.8 µg/L in the F1 and F2 generations, respectively. Growth indices were decreased for F0 adult females and F1 subadults and adults at 48.8 µg/L 2-EHHB. Histopathologic examination of gonads, liver, kidney, and thyroid yielded possible delayed reproductive tract development in F1 subadult males, masculinization of the renal phenotype in F1 adult females (renal tubular eosinophilia) and reduced hepatic energy storage (liver glycogen vacuoles) in F1 (11.3 and 48.8 µg/L) and F2 (48.8 and 101 µg/L) males and females, respectively. Endocrine-related findings included a decrease in anal fin papillae in F2 adult males at 101 µg/L. Results of this study demonstrate effects on growth, development, and reproduction that may be mediated by endocrine (weak estrogenic) and nonendocrine mechanisms. Duration of the MEOGRT should not be routinely extended beyond the OCSPP 890 guideline study design.

2.
Proc Natl Acad Sci U S A ; 117(24): 13680-13688, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32493750

RESUMO

Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor ß-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.


Assuntos
Transtornos Testiculares 46, XX do Desenvolvimento Sexual/metabolismo , Testículo/metabolismo , Proteínas WT1/metabolismo , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/genética , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/patologia , Animais , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Camundongos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/patologia , Proteínas WT1/química , Proteínas WT1/genética , Dedos de Zinco , beta Catenina/genética , beta Catenina/metabolismo
3.
Regul Toxicol Pharmacol ; 134: 105241, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35940297

RESUMO

2-Ethylhexyl 4-hydroxybenzoate (2-EHHB), 4-tert-octylphenol (4-OP), 4-nonylphenol-branched (4-NP), benzyl butyl phthalate (BBP) and dibutyl phthalate (DBP) were evaluated using a 21-day Amphibian Metamorphosis Assay (AMA). Xenopus laevis larvae were exposed nominally to each chemical at 3.6, 10.9, 33.0, and 100 µg/L, except 4-NP concentrations were 1.8, 5.5, 16.5 and 50 µg/L. Endpoints included mortality, developmental stage, hind limb length (HLL), snout-vent length (SVL), body weight (BW), and thyroid histopathology. BBP and 4-OP accelerated development compared to controls at the mean measured concentration of 3.5 and 39.8 µg/L, respectively. An increase in developmental stage frequency distribution was observed for 4-OP at 39.8 and 103 µg/L, BBP at all concentrations and DBP at 143 µg/L. Normalized HLL was increased on study day (SD) 21 for all tested substances except 4-NP. Histopathology revealed accelerated development and mild thyroid follicular cell hypertrophy at all BBP concentrations, but moderate severity at 105 µg/L. Increased BW occurred for all chemicals except 4-OP. Increased SVL was observed for 4-NP, BBP and DBP on SD 21. There was insufficient evidence that 4-NP and 2-EHHB affected the hypothalamic-pituitary thyroid axis, however, BBP, DBP and 4-OP showed potential effects on amphibian metamorphosis and thyroid activity, albeit through different lines of evidence.


Assuntos
Disruptores Endócrinos , Glândula Tireoide , Animais , Bioensaio , Disruptores Endócrinos/toxicidade , Larva , Metamorfose Biológica , Xenopus laevis
4.
Am J Med Genet A ; 185(6): 1666-1677, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33742552

RESUMO

Disorders/differences of sex development (DSD) comprise a group of congenital disorders that affect the genitourinary tract and usually involve the endocrine and reproductive system. The aim of this work was to identify genetic variants responsible for disorders of human urogenital development in a cohort of Egyptian patients. This three-year study included 225 patients with various DSD forms, referred to the genetic DSD and endocrinology clinic, National Research Centre, Egypt. The patients underwent thorough clinical examination, hormonal and imaging studies, detailed cytogenetic and fluorescence in situ hybridization analysis, and molecular sequencing of genes known to commonly cause DSD including AR, SRD5A2, 17BHSD3, NR5A1, SRY, and WT1. Whole exome sequencing (WES) was carried out for 18 selected patients. The study revealed a high rate of sex chromosomal DSD (33%) with a wide array of cytogenetic abnormalities. Sanger sequencing identified pathogenic variants in 33.7% of 46,XY patients, while the detection rate of WES reached 66.7%. Our patients showed a different mutational profile compared with that reported in other populations with a predominance of heritable DSD causes. WES identified rare and novel pathogenic variants in NR5A1, WT1, HHAT, CYP19A1, AMH, AMHR2, and FANCA and in the X-linked genes ARX and KDM6A. In addition, digenic inheritance was observed in two of our patients and was suggested to be a cause of the phenotypic variability observed in DSD.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual/genética , Predisposição Genética para Doença , Genômica , Desenvolvimento Sexual/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Aciltransferases/genética , Adolescente , Adulto , Aromatase/genética , Criança , Pré-Escolar , Estudos de Coortes , Transtorno 46,XY do Desenvolvimento Sexual/fisiopatologia , Egito/epidemiologia , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Feminino , Histona Desmetilases/genética , Proteínas de Homeodomínio/genética , Humanos , Hibridização in Situ Fluorescente , Lactente , Masculino , Proteínas de Membrana/genética , Mutação/genética , Fenótipo , Receptores Androgênicos/genética , Receptores de Peptídeos/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fatores de Transcrição SOXB1/genética , Desenvolvimento Sexual/fisiologia , Fator Esteroidogênico 1/genética , Fatores de Transcrição/genética , Proteínas WT1/genética , Sequenciamento do Exoma , Adulto Jovem
5.
Cytogenet Genome Res ; 156(2): 71-79, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30273929

RESUMO

We report on a female patient who was first evaluated at the age of 6 years with developmental delay, dysmorphic facial features, seizures, and autistic behavior. A brain CT showed complete agenesis of the corpus callosum, and EEG recorded bilateral epileptogenic foci. Karyotype analysis revealed 45,X,psu dic(14;X)(p11;p22). FISH using 14q and Xp subtelomeric probes, combined with a SHOX gene-specific probe, and centromere X and XIST gene analysis revealed ish psu dic(14;X)(D14S1420+; DXYS129-, SHOX-, DXZ1+, XIST+). Array CGH detected a 2-Mb loss at Xp22.33 and a 4.6-Mb gain at Xp22.2p22.12. The deletion contains 34 genes, of which CSF2RA and SHOX are OMIM morbid genes. The duplication also contains some OMIM morbid genes, of which CDKL5, NH5, RPS6KA3, and AP1S2 are the most important. The late replicating chromatin technique was used to detect the pattern of X inactivation in the normal X and in the translocated chromosome. The translocated X was found to be inactive in 70% of the studied blood lymphocytes with patchy extension of inactivation to chromosome 14. In conclusion, the phenotype of the patient may be partially affected by the haploinsufficiency of the genes that are known to escape X inactivation and that lie within the deleted region and by other deleted or duplicated genes on the abnormal X chromosome due to an alternative pattern of X inactivation. The phenotype of the patient was significantly aggravated and complicated by the functional monosomy of some genes on chromosome 14 due to partial spreading of inactivation and silencing of those genes. This case report indicates the importance of structural and functional studies and emphasizes the clinical importance of the follow-up of abnormal microarrays.

6.
J Sex Med ; 14(9): 1165-1174, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28859874

RESUMO

BACKGROUND: Mutations in the HSD17B3 gene are associated with a 46,XY disorder of sexual development (46,XY DSD) as a result of low testosterone production during embryogenesis. AIM: To elucidate the molecular basis of the disorder by chemically analyzing four missense mutations in HSD17B3 (T54A, M164T, L194P, G289S) from Egyptian patients with 46,XY DSD. METHODS: Expression plasmids for wild-type 17ß-hydroxysteroid hydrogenase type 3 (17ß-HSD3) and mutant enzymes generated by site-directed mutagenesis were transiently transfected into human HEK-293 cells. Protein expression was verified by western blotting and activity was determined by measuring the conversion of radiolabeled Δ4-androstene-3,17-dione to testosterone. Application of a homology model provided an explanation for the observed effects of the mutations. OUTCOMES: Testosterone formation by wild-type and mutant 17ß-HSD3 enzymes was compared. RESULTS: Mutations T54A and L194P, despite normal protein expression, completely abolished 17ß-HSD3 activity, explaining their severe 46,XY DSD phenotype. Mutant M164T could still produce testosterone, albeit with significantly lower activity compared with wild-type 17ß-HSD3, resulting in ambiguous genitalia or a microphallus at birth. The substitution G289S represented a polymorphism exhibiting comparable activity to wild-type 17ß-HSD3. Sequencing of the SRD5A2 gene in three siblings bearing the HSD17B3 G289S polymorphism disclosed the homozygous Y91H mutation in the former gene, thus explaining the 46,XY DSD presentations. Molecular modeling analyses supported the biochemical observations and predicted a disruption of cofactor binding by mutations T54A and M164T and of substrate binding by L196P, resulting in the loss of enzyme activity. In contrast, the G289S substitution was predicted to disturb neither the three-dimensional structure nor enzyme activity. CLINICAL TRANSLATION: Biochemical analysis of mutant 17ß-HSD3 enzymes is necessary to understand genotype-phenotype relationships. STRENGTHS AND LIMITATIONS: Biochemical analysis combined with molecular modeling provides insight into disease mechanism. However, the stability of mutant proteins in vivo cannot be predicted by this approach. CONCLUSION: The 17ß-HSD3 G289S substitution, previously reported in other patients with 46,XY DSD, is a polymorphism that does not cause the disorder; thus, further sequence analysis was required and disclosed a mutation in SRD5A2, explaining the cause of 46,XY DSD in these patients. Engeli RT, Tsachaki M, Hassan HA, et al. Biochemical Analysis of Four Missense Mutations in the HSD17B3 Gene Associated With 46,XY Disorders of Sex Development in Egyptian Patients. J Sex Med 2017;14:1165-1174.


Assuntos
17-Hidroxiesteroide Desidrogenases/genética , Transtorno 46,XY do Desenvolvimento Sexual/enzimologia , Transtorno 46,XY do Desenvolvimento Sexual/genética , Mutação de Sentido Incorreto , 17-Hidroxiesteroide Desidrogenases/metabolismo , Transtorno 46,XY do Desenvolvimento Sexual/sangue , Egito , Feminino , Genótipo , Células HEK293 , Homozigoto , Humanos , Masculino , Fenótipo , Testosterona/sangue
7.
J Toxicol Environ Health A ; 80(4): 236-249, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28569618

RESUMO

Triclosan (TCS), an antibacterial, has been shown to be an endocrine disruptor in the rat. Previously, subchronic TCS treatment to female rats was found to advance puberty and potentiate the effect of ethinyl estradiol (EE) on uterine growth when EE and TCS were co-administered prior to weaning. In the pubertal study, a decrease in serum thyroxine (T4) concentrations with no significant change in serum thyroid-stimulating hormone (TSH) was also observed. The purpose of the present study was to further characterize the influence of TCS on the reproductive and thyroid axes of the female rat using a chronic exposure regimen. Female Wistar rats were exposed by oral gavage to vehicle control, EE (1 µg/kg), or TCS (2.35, 4.69, 9.375 or 37.5 mg/kg) for 8 months and estrous cyclicity monitored. Although a divergent pattern of reproductive senescence appeared to emerge from 5 to 11 months of age between controls and EE-treated females, no significant difference in cyclicity was noted between TCS-treated and control females. A higher % control females displayed persistent diestrus (PD) by the end of the study, whereas animals administered with positive control (EE) were predominately persistent estrus (PE). Thyroxine concentration was significantly decreased in TCS-administered 9.375 and 37.5 mg/kg groups, with no marked effects on TSH levels, thyroid tissue weight, or histology. Results demonstrate that a long-term exposure to TCS did not significantly alter estrous cyclicity or timing of reproductive senescence in females but suppressed T4 levels at a lower dose than previously observed.


Assuntos
Envelhecimento/efeitos dos fármacos , Ciclo Estral/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Triclosan/toxicidade , Animais , Anti-Infecciosos Locais/toxicidade , Feminino , Ratos , Ratos Wistar , Testes de Toxicidade Crônica
8.
Am J Med Genet A ; 170A(4): 1050-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26749249

RESUMO

Many chromosomal rearrangements that lead to copy-number gains or losses have been shown to cause distinctive and recognizable clinical phenotypes. Conventional cytogenetic analysis can detect many, but not all, rearrangements depending on its power of resolution. The wide use of whole-genome array-based comparative genomic hybridization (array-CGH) techniques has allowed the detection of novel syndromes and to establish genotype-phenotype correlations by delineating at high resolution the regions involved in specific chromosomal aberrations. We report on a two and half-year-old female patient with intellectual disability and distinctive phenotypic features resulting from a de novo duplication of about 0.3 Mb in 21q22.3 associated with duplication of about 0.3 Mb in 12p13.33. The patient's chromosomal abnormalities were identified at the cytogenetic molecular level, using SNP array analysis, while GTG banding technique revealed a normal karyotype. Clinical findings of the patient were compared with Down syndrome and 12p duplication syndrome. This study suggests that an area of contiguous genes on the distal part of chromosome 21 (21q22.3) contribute to the Down syndrome phenotype and indicates that genes in the distal region of 12p (12p13.33) account for many facial characteristics and hypotonia of trisomy 12p syndrome.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 21 , Estudos de Associação Genética , Fenótipo , Trissomia , Encéfalo/patologia , Pré-Escolar , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Variações do Número de Cópias de DNA , Fácies , Feminino , Humanos , Cariotipagem , Imageamento por Ressonância Magnética , Polimorfismo de Nucleotídeo Único
9.
Am J Med Genet A ; 167A(1): 128-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25425358

RESUMO

We describe a large family from the Gaza Strip presented with multiple congenital anomalies. The proband was presented with intellectual disability and multiple congenital anomalies including cleft palate, low-set ears, everted upper lip, diaphragmatic hernia, and arthrogryposis. Pedigree analysis showed 19 affected patients over five generations, only 6 were alive and 11 individuals were obligate carriers. The proband had an apparently normal karyotype, although FISH studies showed a derivative chromosome 1 with duplication of 16p13.3 and deletion of the 1p subtelomere. Her father however had a balanced translocation. The seven affected patients had a similar phenotype, one of them died before genetic testing was carried out and the living six patients had the same unbalanced translocation. Array CGH revealed an 8.8 Mb duplication in 16p13 and 200,338 bp deletion in 1p36.3. Accordingly, intellectual disability, hypertelorism, cupped ears, everted upper lip, and limb anomalies were presenting clinical features of the 16p13 duplication syndrome while deep set eyes were perhaps related to the 1p terminal deletion. Prevention of recurrent intellectual disability in this family can be achieved through carrier detection and prenatal genetic diagnosis.


Assuntos
Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 1/genética , Características da Família , Deficiência Intelectual/genética , Duplicações Segmentares Genômicas/genética , Translocação Genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Análise Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Lactente , Masculino , Linhagem , Fenótipo
10.
Hormones (Athens) ; 23(2): 305-312, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38526829

RESUMO

PURPOSE: Leydig cell hypoplasia (LCH) type II is a rare disease with only a few cases reported. Patients presented with hypospadias, micropenis, undescended testes, or infertility. In this study, we report a new patient with compound heterozygous variants in the LHCGR gene and LCH type II phenotype. METHODS: Whole exome sequencing (WES) was performed followed by Sanger sequencing to confirm the detected variants in the patient and his parents. RESULTS: A novel missense variant (p.Phe444Cys) was identified in a highly conserved site and is verified to be in trans with the signal peptide's 33-bases insertion variant. CONCLUSION: Our research provides a more comprehensive clinical and genetic spectrum of Leydig cell hypoplasia type II. It highlighted the importance of WES in the diagnosis of this uncommon genetic disorder as well as the expansion of the genotype of LCH type II.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual , Fenótipo , Receptores do LH , Humanos , Masculino , Receptores do LH/genética , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Sequenciamento do Exoma , Sinais Direcionadores de Proteínas/genética , Mutação de Sentido Incorreto , Erros Inatos do Metabolismo de Esteroides/genética , Alelos , Testículo/anormalidades
12.
Am J Med Genet A ; 158A(7): 1594-603, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22628100

RESUMO

Isodicentric chromosome formation is the most common structural abnormality of the Y chromosome. As dicentrics are mitotically unstable, they are subsequently lost during cell division resulting in mosaicism with a 45,X cell line. We report on six patients with variable signs of disorders of sex development (DSD) including ambiguous genitalia, short stature, primary amenorrhea, and male infertility with azoospermia. Cytogenetic studies showed the presence of a sex chromosome marker in all patients; associated with a 45,X cell line in five of them. Fluorescence in situ hybridization (FISH) technique was used to determine the structure and the breakage sites of the markers that all proved to be isodicentric Y chromosomes. Three patients, were found to have similar breakpoints: idic Y(qter→ p11.32:: p11.32→ qter), two of them presented with ambiguous genitalia and were found to have ovotesticular DSD, while the third presented with short stature and hypomelanosis of Ito. One female patient presenting with primary amenorrhea, Turner manifestations and ambiguous genitalia revealed the breakpoint: idic Y (pter→q11.1::q11.1→pter). The same breakpoint was detected in a male with azoospermia but in non-mosaic form. An infant with ambiguous genitalia and mixed gonadal dysgenesis (MGD) had the breakpoint at Yq11.2: idic Y(pter→q11.2::q11.2→pter). SRY signals were detected in all patients. Sequencing of the SRY gene was carried out for three patients with normal results. This study emphasizes the importance of FISH analysis in the diagnosis of patients with DSD as well as the establishment of the relationship between phenotype and karyotype.


Assuntos
Cromossomos Humanos Y , Transtornos do Desenvolvimento Sexual/genética , Aberrações dos Cromossomos Sexuais , Adolescente , Adulto , Criança , Pré-Escolar , Bandeamento Cromossômico , Transtornos do Desenvolvimento Sexual/diagnóstico , Egito , Feminino , Humanos , Hibridização in Situ Fluorescente , Lactente , Cariótipo , Masculino , Fenótipo , Adulto Jovem
13.
Sex Dev ; 16(4): 261-265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35045414

RESUMO

INTRODUCTION: Disorders of gonadal development represent a clinically and genetically heterogeneous group of DSD, and the etiology in many cases remains unknown, indicating that our knowledge of factors controlling sex determination is still limited. METHODS: We describe a 46,XY DSD patient from Egypt. The patient was reared as female, born to consanguineous parents, and was referred to us at the age of 5 years because of ambiguous genitalia. On examination, the girl was microcephalic (head circumference -3 SD), but her height and weight were normal for her age and sex. RESULTS: Exome sequencing identified a homozygous variant in the hedgehog acyltransferase (HHAT) gene, which encodes an enzyme that is required for multimerization and signaling potency of the hedgehog secreted proteins. The variant is a novel homozygous missense change c.1329C>A (p.N443K), located within transmembrane domain 9, which segregated with the phenotype in the family. DISCUSSION/CONCLUSION: Our results expand the phenotypic spectrum associated with HHAT variants to include 46,XY gonadal dysgenesis and reinforce the role of exome sequencing in unraveling new genes that play a pivotal role in sexual development.


Assuntos
Disgenesia Gonadal 46 XY , Proteínas Hedgehog , Feminino , Humanos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Disgenesia Gonadal 46 XY/diagnóstico , Mutação de Sentido Incorreto/genética , Homozigoto , Fenótipo , Mutação , Aciltransferases/genética
14.
Environ Sci Technol ; 45(22): 9711-8, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21973115

RESUMO

A variety of agricultural films are commercially available for managing emissions and enhancing pest control during soil fumigation. These films are manufactured using different materials and processes which can ultimately result in different permeability to fumigants. A systematic laboratory study of the permeability of the agricultural films to nine fumigants was conducted to evaluate the performance of commonly used film products, including polyethylene, metalized, and high-barrier films. The permeability, as expressed by mass transfer coefficient (cm/h), of 27 different films from 13 manufacturers ranged from below 1 × 10(-4) cm/h to above 10 cm/h at 25 °C under ambient relative humidity test conditions. The wide range in permeability of commercially available films demonstrates the need to use films which are appropriate for the fumigation application. The effects of environmental factors, such as temperature and humidity, on the film permeability were also investigated. It was found that high relative humidity could drastically increase the permeability of the high-barrier films. The permeability of some high-barrier films was increased by 2-3 orders of magnitude when the films were tested at high relative humidity. Increasing the temperature from 25 to 40 °C increased the permeability for some high-barrier films up to 10 times more than the permeability at 25 °C, although the effect was minimal for several of these films. Analysis of the distribution of the permeability of the films under ambient humidity conditions to nine fumigants indicated that the 27 films largely followed the material type, although the permeability varied considerably among the films of similar material.


Assuntos
Fumigação , Praguicidas/química , Agricultura/instrumentação , Fumigação/métodos , Umidade , Permeabilidade , Controle de Pragas/instrumentação , Polietileno/química , Temperatura
15.
Mol Syndromol ; 12(2): 87-95, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34012377

RESUMO

Mowat-Wilson syndrome (MWS) is a rare autosomal dominant syndrome characterized by dysmorphic features, mental retardation, and congenital heart disease (CHD). MWS results from microdeletions of chromosome 2q23 or de novo SNVs involving the ZEB2 gene. Here, we report on an Egyptian MWS patient diagnosed by chromosomal microarray (CMA). A 1-year-old male child was referred to the CHD clinic, National Research Centre, presenting with dysmorphic features and CHD. The patient was referred to the human cytogenetics department for cytogenetic analysis and for screening of subtelomere rearrangements and microdeletion loci, using MLPA, and all revealed normal results. CMA revealed an interstitial 2.27-Mb microdeletion in chromosome 2q, involving the entire ZEB2 gene and other genes. This study emphasizes the significance of CMA in the detection of microdeletions/microduplications and as a screening tool in cases presenting with CHD and extracardiac manifestations. MWS should be suspected in patients presenting with the characteristic facial dysmorphism, developmental delay, seizures, Hirschsprung disease, and congenital heart anomalies, especially those involving the pulmonary arteries or pulmonary valves. It is recommended to include the ZEB2 locus in the MLPA microdeletions probes.

16.
J Pediatr Genet ; 10(2): 131-138, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33996184

RESUMO

Paternal microduplication of 11p14.3-p15.5 causes the clinical manifestations of Beckwith-Wiedemann syndrome (BWS), while microdeletion of 18q23-ter is clinically characterized by short stature, congenital malformations, and developmental delay. We describe a 15-month-old girl presenting with protruding tongue, dysmorphic facial features, moderate developmental delay, umbilical hernia, hypotonia, mild-to-moderate pulmonary hypertension, small patent ductus arteriosus, and mild ventricular septal hypertrophy. Brain magnetic resonance imaging showed mild atrophic changes. Chromosomal analysis revealed 46, XX, add(18)(q23). Fluorescence in situ hybridization using subtelomere 18q and whole chromosome painting 18 showed subtelomere deletion in 18q, and the add segment was not derived from chromosome 18. Microarray-based comparative genomic hybridization detected a 22 Mb duplication of chromosome 11p15.5p14.3 and a 3.7 Mb deletion of chromosome 18q23. The phenotype of the chromosomal rearrangements is probably resulted from a combination of dosage-sensitive genes. Our patient had clinical manifestations of both 18q deletion and BWS.

17.
Mol Genet Genomic Med ; 9(2): e1546, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33217222

RESUMO

BACKGROUND: Wolf-Hirschhorn syndrome (WHS) (OMIM 194190) is a multiple congenital anomalies/intellectual disability syndrome. It is caused by partial loss of genetic material from the distal portion of the short arm of chromosome. METHODS: We studied the phenotype-genotype correlation. RESULTS: We present the clinical manifestations and cytogenetic results of 10 unrelated Egyptian patients with 4p deletions. Karyotyping, FISH and MLPA was performed for screening for microdeletion syndromes. Array CGH was done for two patients. All patients exhibited the cardinal clinical manifestation of WHS. FISH proved deletion of the specific WHS locus in all patients. MLPA detected microdeletion of the specific locus in two patients with normal karyotypes, while array CGH, performed for two patients, has delineated the extent of the deleted segments and the involved genes. LETM1, the main candidate gene for the seizure phenotype, was found deleted in the two patients tested by array CGH; nevertheless, one of them did not manifest seizures. The study emphasized the previous. CONCLUSION: WHS is a contiguous gene syndrome resulting from hemizygosity of the terminal 2 Mb of 4p16.3 region. The Branchial fistula, detected in one of our patients is a new finding that, to our knowledge, was not reported.


Assuntos
Genótipo , Fenótipo , Síndrome de Wolf-Hirschhorn/genética , Proteínas de Ligação ao Cálcio/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Humanos , Hibridização in Situ Fluorescente , Lactente , Cariotipagem , Masculino , Proteínas de Membrana/genética , Síndrome de Wolf-Hirschhorn/patologia
18.
Mol Genet Genomic Med ; 9(11): e1829, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34609792

RESUMO

BACKGROUND: This study aimed to delineate the clinical phenotype of patients with 9p deletions, pinpoint the chromosomal breakpoints, and identify the critical region for trigonocephaly, which is a frequent finding in 9p terminal deletion. METHODS: We investigated a cohort of nine patients with chromosome 9p terminal deletions who all displayed developmental delay, intellectual disability, hypotonia, and dysmorphic features. Of them, eight had trigonocephaly, seven had brain anomalies, seven had autistic manifestations, seven had fair hair, and six had a congenital heart defect (CHD). RESULTS: Karyotyping revealed 9p terminal deletion in all patients, and patients 8 and 9 had additional duplication of other chromosomal segments. We used six bacterial artificial chromosome (BAC) clones that could identify the breakpoints at 17-20 Mb from the 9p terminus. Array CGH identified the precise extent of the deletion in six patients; the deleted regions ranged from 16 to 18.8 Mb in four patients, patient 8 had an 11.58 Mb deletion and patient 9 had a 2.3 Mb deletion. CONCLUSION: The gene deletion in the 9p24 region was insufficient to cause ambiguous genitalia because six of the nine patients had normal genitalia. We suggest that the critical region for trigonocephaly lies between 11,575 and 11,587 Mb from the chromosome 9p terminus. To the best of our knowledge, this is the minimal critical region reported for trigonocephaly in 9p deletion syndrome, and it warrants further delineation.


Assuntos
Deleção Cromossômica , Craniossinostoses , Cromossomos , Craniossinostoses/genética , Egito , Humanos , Cariotipagem
19.
J AOAC Int ; 93(2): 389-99, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20480883

RESUMO

A multiresidue method was developed and validated for the determination of 13 neonicotinoid pesticides and metabolites, and nine macrocyclic lactone pesticides and veterinary drugs using SPE and ultra-performance liquid chromatography/MS/MS. The method was validated in milk, orange, spinach, apple, plum, watermelon, green bean, zucchini, broccoli, strawberry, grape, and tomato by analyzing replicates of residue-free control samples fortified with a mixture of 22 target analytes at three concentration levels. The recoveries of the analytes from the fortified matrixes were mostly within 70-120%, except for some of the neonicotinoid metabolites. The LOD values varied by analyte and matrix and ranged between 0.001-2 ng/g. The developed method was successful in combining two widely different classes of compounds into a single analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lactonas/análise , Resíduos de Praguicidas/análise , Animais , Bovinos , Contaminação de Alimentos/análise , Frutas , Espectrometria de Massas/métodos , Leite , Modelos Químicos , Peso Molecular , Praguicidas/análise , Reprodutibilidade dos Testes , Verduras
20.
Mol Syndromol ; 11(5-6): 284-295, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33510599

RESUMO

Monosomy 1p36 syndrome is one of the most common submicroscopic deletion syndromes, which is characterized by the presence of delayed developmental milestones, intellectual disability, and clinically recognizable dysmorphic craniofacial features. The syndrome comprises 4 cytogenetic groups including pure terminal deletions, interstitial deletions, complex rearrangements, and derivative chromosomes 1 due to unbalanced translocations, where unbalanced translocations represent the least percentage of all cases of monosomy 1p36 (7%). Most patients with monosomy 1p36 due to an unbalanced translocation can be cytogenetically diagnosed using conventional techniques. However, chromosomal microarray analysis is mandatory in these cases to detect copy number variance and size of the deletion and allows for setting a phenotype-genotype correlation. Here, we studied a 1.5-year-old female patient who showed intellectual disability, delayed milestones, hypotonia, seizures, and characteristic dysmorphic features including brachycephaly, straight eyebrows, deep-set eyes, downslanting palpebral fissures, midface hypoplasia, depressed nasal bridge, long philtrum, and pointed chin. Conventional cytogenetic analysis (CCA), microarray study, and fluorescence in situ hybridization (FISH) analysis were performed. CCA showed a translocation involving chromosomes 1 and 21, 45,XX,der(1)t(1;21)(p36.32;q21.1)dn. Microarray analysis revealed copy number losses at both 1p36 and proximal 21q. FISH confirmed the presence of the 1p36 deletion, but was not performed for 21q. We have concluded that phenotype-genotype correlation for monosomy 1p36 syndrome can be performed for the fundamental clinical manifestations; however, the final aspect of the syndrome depends on composite factors. Monosomy 1p36 due to unbalanced translocation may present either classically or with additional altered features of various severity based on the copy number variations involving different chromosomes.

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