Prevalence and predictors of thyroid cancer among thyroid nodules: a retrospective cohort study of 1,000 patients.

INTRODUCTION: Thyroid cancer is increasing in incidence globally due either to early detection (overestimation) or true increment. A recent debate concerns multinodular goitre (MNG) or toxic goitres which have classically been considered at a lower risk for cancer. METHODS: In this study, we enrolled retrospectively all patients with nodular goitre treated at our tertiary hospital and analysed their data with the aim of detecting the rate of cancer among different types of nodular goitre. We also studied predictors of incidental malignancy among thyroidectomies. RESULTS: A predilection for solitary thyroid nodules (STNs) was found in women of younger age, with STNs tending to be larger in comparison with MNG in the same age group. However, both types of nodules were at equal risk of harbouring malignancy. Thyroid Imaging Reporting and Data System (TI-RADS) and Bethesda scores were the only dependent predictors of malignancy within thyroid nodules. CONCLUSION: The authors recommend management of both STNs and MNG using the same algorithm.

MCNP5 evaluation of photoneutron production from the Alexandria University 15 MV Elekta Precise medical LINAC.

Photoneutron production, and the dose equivalent, in the head assembly of the 15 MV Elekta Precise medical linac; operating in the faculty of Medicine at Alexandria University were estimated with the MCNP5 code. Photoneutron spectra were calculated in air and inside a water phantom to different depths as a function of the radiation field sizes. The maximum neutron fluence is 3.346×10-9 n/cm2-e for a 30×30 cm2 field size to 2-4 cm-depth in the phantom. The dose equivalent due to fast neutron increases as the field size increases, being a maximum of 0.912 ± 0.05 mSv/Gy at depth between 2 and 4 cm in the water phantom for 40×40 cm2 field size. Photoneutron fluence and dose equivalent are larger to 100 cm from the isocenter than to 35 cm from the treatment room wall.

Laser spectrometry for multi-elemental imaging of biological tissues.

An increasing interest has arisen in research focused on metallic and organic ions that play crucial roles in both physiological and pathological metabolic processes. Current methods for the observation of trace elements in biological tissues at microscopic spatial resolution often require equipment with high complexity. We demonstrate a novel approach with an all-optical design and multi-elemental scanning imaging, which is unique among methods of elemental detection because of its full compatibility with standard optical microscopy. This approach is based on laser-induced breakdown spectroscopy (LIBS), which allows the elements in a tissue sample to be directly detected and quantified under atmospheric pressure. We successfully applied this method to murine kidneys with 10 µm resolution and a ppm-level detection limit to analyze the renal clearance of nanoparticles. These results offer new insight into the use of laser spectrometry in biomedical applications in the field of label-free elemental mapping of biological tissues.

The use of theranostic gadolinium-based nanoprobes to improve radiotherapy efficacy.

A new efficient type of gadolinium-based theranostic agent (AGuIX®) has recently been developed for MRI-guided radiotherapy (RT). These new particles consist of a polysiloxane network surrounded by a number of gadolinium chelates, usually 10. Owing to their small size (<5 nm), AGuIX typically exhibit biodistributions that are almost ideal for diagnostic and therapeutic purposes. For example, although a significant proportion of these particles accumulate in tumours, the remainder is rapidly eliminated by the renal route. In addition, in the absence of irradiation, the nanoparticles are well tolerated even at very high dose (10 times more than the dose used for mouse treatment). AGuIX particles have been proven to act as efficient radiosensitizers in a large variety of experimental in vitro scenarios, including different radioresistant cell lines, irradiation energies and radiation sources (sensitizing enhancement ratio ranging from 1.1 to 2.5). Pre-clinical studies have also demonstrated the impact of these particles on different heterotopic and orthotopic tumours, with both intratumoural or intravenous injection routes. A significant therapeutical effect has been observed in all contexts. Furthermore, MRI monitoring was proven to efficiently aid in determining a RT protocol and assessing tumour evolution following treatment. The usual theoretical models, based on energy attenuation and macroscopic dose enhancement, cannot account for all the results that have been obtained. Only theoretical models, which take into account the Auger electron cascades that occur between the different atoms constituting the particle and the related high radical concentrations in the vicinity of the particle, provide an explanation for the complex cell damage and death observed.

Toxicity of the Red Sea pufferfish Pleuranacanthus sceleratus "El-Karad".

The pufferfish Pleuranacanthus sceleratus (El-Karad) represents serious public health problems, because of its responsibility for many incidents in Egypt, especially in the Suez Gulf. In the present study, samples of this fish were collected monthly and the toxins were extracted from gonads, liver, digestive tract, muscles, and skin, then purified and identified using TLC and electrophoresis. The alkaline hydrolyzates of these toxins were also detected using UV absorption and GC-mass spectra of their trimethylsilyl derivatives.

Laparoscopic assisted cystectomy and lymphadenectomy for bladder cancer: initial experience.

This study discusses our initial experience in the field of laparoscopic management of bladder carcinoma. Ten patients with invasive bladder tumors of variable histology and ranging from stage T2 to T3b were submitted to this procedure. Intraoperative assessment, lateral dissection, posterior dissection, anterior dissection, and urethral transection were achieved laparoscopically. The specimen retrieval and continent pouch construction was performed through a limited abdominal incision. This new regimen allows precise radical lymphadenectomy, early postoperative mobility, fewer wound complications, and shorter hospital stay. The early postoperative results of this procedure are encouraging. Modification and continuous refinement of the technique is still ongoing.

Haplotypes and mutations of the PAH locus in Egyptian families with PKU.

A high degree of molecular heterogeneneity at the phenylalanine hydroxylase (PAH) locus was established by examining RFLP haplotypes and PAH mutations in the families of 13 Egyptians with phenylketenouria (PKU). Thirteen different haplotypes were unequivocally determined in these kindreds. Haplotypes 1.8, 3.9, 4.3, 7.8, 22.11, 27.6, and 52.8 were found segregating with normal chromosomes, whilst haplotypes 1.8, 5.9, 23.8, 32.8, the newly assigned 73.9, and two as yet incomplete but novel haplotypes were found segregating with the mutant chromosomes. There was no particular preference for a single haplotype among normal or mutant chromosomes. Nine different mutations were also identified among the 26 alleles. IVS 10nt11g (8/26), IVS 2nt5g-c (4/26), R261Q (3/26), R176X (2/26), Y206D (2/26), S231P (2/26), Y198fs [593-614del22bp]; (2/26), G46fs [136/137delG]; (1/26), and E178G (1/26). Six of these mutations (IVS 2nt5g-c, R176X, Y198fs, R261Q, S231P, and IVS 10nt11g) are common to other Mediterranean populations. Two mutations not previously reported in the Mediterranean basin were also observed (Y206D and G46fs). These intriguing preliminary findings confirm IVS 10nt11g as a major mutation among Mediterranean mutations and demonstrate the need for a more comprehensive study of Arab populations to confirm the uniqueness of the two novel mutations to the Egyptian population.

Nucleolus organizer region heteromorphism in patients with Down syndrome and their parents.

The study aimed to evaluate the role of nucleolus organizer region (NOR) heteromorphism as an etiological factor for parental nondisjunction in Down syndrome by comparing 25 patients affected by Down syndrome, and their parents with a control group of 80 non-affected Egyptians. All parents had normal karyotypes. The average modal number per parent of Ag-positive NORs was significantly higher in parents than controls. A significant difference in the size of the double-NOR variants (dNORs) was found. The mean maternal and paternal ages were significantly lower, with a significant increase in spontaneous abortions, for dNOR(+) couples compared with dNOR(-) couples.

A diagnostic clinical genetic study of craniofacial dysmorphism.

A diagnostic evaluation of craniofacial anomalies, either isolated or as part of a genetic syndrome was conducted on 25 patients (8 females, 17 males), age range 2 months to 47 years. Complete genetic examination, pedigree analysis, anthropometric measurements and radiological studies were carried out. Cytogenetic studies included fluorescence in situ hybridization (FISH) when indicated. In all, 15 patients had chromosomal abnormalities. Five patients had unbalanced chromosome rearrangements and six had chromosome markers. Three patients were FISH-positive for William syndrome and one was positive for Prader-Willi syndrome. Ten patients had monogenic disorders. Five were diagnosed as craniosynostosis syndromes. We conclude that minor features are useful for making a diagnosis of congenital anomalies.

Nucleolus organizer region heteromorphism in patients with Down syndrome and their parents

The study aimed to evaluate the role of nucleolus organizer region [NOR] heteromorphism as an etiological factor for parental nondisjunction in Down syndrome by comparing 25 patients affected by Down syndrome, and their parents with a control group of 80 non-affected Egyptians. All parents had normal karyotypes. The average modal number per parent of Ag-positive NORs was significantly higher in parents than controls. A significant difference in the size of the double-NOR variants [dNORs] was found. The mean maternal and paternal ages were significantly lower, with a significant increase in spontaneous abortions, for dNOR[+] couples compared with dNOR[-] couples

Autosomal recessive disorders among patients attending the genetics clinic in Alexandria

A total of 660 patients referred to the genetics clinic, Medical Research Institute, Alexandria were assessed to determine the frequency of genetic disorders and the proportion of autosomal recessive disorders. It was found that 298 [45.2%] patients had genetic disorders, 100 [33.6%] of whom had an autosomal recessive disorder; these included 32 patients with metabolic defects, 18 with haemoglobinopathies and 50 with syndromes and single defects. The frequency of consanguinity among parents of patients with autosomal recessive disorders was high [60%, with 48% first cousins]. The average inbreeding coefficient was higher [0.03] than that reported for the Egyptian population in general [0.01]

Chromosome anomalies in normal androgenized infertile males.

Chromosome anomalies are known to play a role in human infertility. Chromosome analysis of 103 normal androgenized infertile azoospermic (97.1%) or oligospermic (2.9%) males revealed that the frequency of chromosomal abnormalities was 8.7%. Two patients (1.94%) had a 46,XX chromosome complement, one patient (0.97%) had a 45,X karyotype, two patients (1.94%) had a 45,XY,t(13;14)(p11;q11) karyotype, one patient (0.97%) had a 46,XY,inv(9)(p12;q13) chromosome constitution, two patients (1.94%) had a 46,XY,del(Y)(q12) karyotype, and one patient (0.97%) had a 45X/46,X+marker the nature of which was not clarified.

Duplication 3q(q21----qter) without limb anomalies.

We report on a 2.5-month-old boy with hypertelorism, hypertrichosis, anteverted nostrils, malformed ears, thin lips, downturned corners of the mouth, micrognathia, short neck, cryptorchidism, and bilateral simian creases without limb anomalies. Cytogenetic studies showed a duplication 3q----qter 46,XY,der(6),t(3;6)(q21;p25)pat. The absence of limb anomalies is noteworthy; all 12 previously reported patients with the same duplication had limb anomalies. The uniqueness of this report provokes speculations regarding limb morphogenesis in embryos with chromosome anomalies. The concepts of chronogenetics, heterochrony, and developmental field defects appear relevant to yet another set of patients with chromosome anomalies.