Neck pain in Iranian school teachers: Prevalence and risk factors

Neck pain (NP) is a common occupational health problem associated with a number of professions. Many studies indicate that NP is common among teachers, yet no published study was found to address the prevalence and risk factors of NP in Iranian school teachers. The purpose of the current study was to assess the prevalence and risk factors for NP among school teachers in Iran. A cross-sectional study was conducted on 586 randomly selected primary and high schools teachers from 22 schools in Tehran, Iran. Point, last month, last 6 months, annual, and lifetime prevalence rates of NP were 24%, 29%, 33%, 37%, and 43%, respectively. There was a significant association and increased prevalence of NP with a number of risk factors such as; being female, age, general health, length of employment, regular exercise and job satisfaction (P < 0.05 in all instances). Therefore, some individual and occupational factors may make conditions relevant for the development of NP among teachers.     

Single-Domain Antibodies or Nanobodies: A Class of Next-Generation Antibodies

Nanobodies for the first time were identified in the sera of Camelidae. Single-domain antibodies or nanobodies are a class of next-generation antibodies that have specific features: small size (in nanoscale), high penetration in various tissues, high stability in hard situations and ease production process in microbial systems. In fact single-domain antibodies are the smallest fragment of the antibody with binding ability. Unique characteristics and features of nanobodies make them an appropriate candidate for further evaluation as the development of novel antibody-based therapeutics. In this regard single-domain antibodies are in the interest of many researchers as well as biopharmaceutical companies for diagnostic and therapeutic applications. Nowadays several single domain antibodies have been developed and evaluated in different clinical trials. Because of many advantages of single-domain antibodies over other formats of antibodies, they could be good replacement for other formats of antibodies in near future. Here, we review the biology, engineering platforms and application of nanobodies.     

1,2,3-Triazole framework: a strategic structure for C–H⋯X hydrogen bonding and practical design of an effective Pd-catalyst for carbonylation and carbon–carbon bond formation

1,2,3-Triazole is an interesting N-heterocyclic framework which can act as both a hydrogen bond donor and metal chelator. In the present study, C–H hydrogen bonding of the 1,2,3-triazole ring was surveyed theoretically and the results showed a good agreement with the experimental observations. The click-modified magnetic nanocatalyst Pd@click-Fe₃O₄/chitosan was successfully prepared, in which the triazole moiety plays a dual role as both a strong linker and an excellent ligand and immobilizes the palladium species in the catalyst matrix. This nanostructure was well characterized and found to be an efficient catalyst for the CO gas-free formylation of aryl halides using formic acid (HCOOH) as the most convenient, inexpensive and environmentally friendly CO source. Here, the aryl halides are selectively converted to the corresponding aromatic aldehydes under mild reaction conditions and low Pd loading. The activity of this catalyst was also excellent in the Suzuki cross-coupling reaction of various aryl halides with phenylboronic acids in EtOH/H₂O (1 : 1) at room temperature. In addition, this catalyst was stable in the reaction media and could be magnetically separated and recovered several times.

The C–H hydrogen bonding of a 1,2,3-triazole framework was studied. An Fe₃O₄–chitosan core–shell incorporating a triazole/Pd complex was investigated as a nanocatalyst in carbonylation and C–C coupling.     

Prevalence, anatomic patterns, valvular competence, and clinical significance of the Giacomini vein

OBJECTIVE: Coursing the posterior thigh as a tributary or trunk projection of the small saphenous vein (SSV), the Giacomini vein's clinical significance in chronic venous disease (CVD) remains undetermined. This cross-sectional controlled study examined the prevalence, anatomy, competency status, and clinical significance of the Giacomini vein across the clinical spectrum of CVD in relation to the SSV termination. METHODS: One hundred eighty-nine consecutive subjects (301 limbs) with suspected CVD (109 men, 80 women; age, 18-87 years [median, 61 years]) underwent examination, clinical class (CEAP) stratification, and duplex ultrasound determination of the sites and extent of reflux >0.5 sec) and Giacomini vein's anatomy. RESULTS: A Giacomini vein was found in 70.4% of limbs (212 of 301; 95% confidence interval, 65%-75.6%). Extent, pattern, and sites of reflux in all named superficial and deep veins were evenly distributed in limbs with and without a Giacomini vein; perforator vein incompetence in thigh and calf was also balanced (all, P > .2). Giacomini vein had no effect ( P > .2) on SSV termination anatomy, displaying a similar prevalence in classes C(0-6) . In 212 limbs, either as a tributary or trunk projection of the SSV, the Giacomini vein ascended subfascially (n = 210) to the lower (8%; n = 17), middle (47.6%; n = 101), or upper (44.3%; n = 94) thigh, and terminated at the deep system (45.3%; n = 96) and/or perforated the fascia (64.2%; n = 136), to join the superficial system. Giacomini vein morphology was not affected by the SSV termination anatomy and CEAP clinical class. Incompetence was detected less often (P < .001) in the Giacomini vein (4.7%; n = 10 of 212) than in the saphenous trunks cumulatively (53.3%; n = 113 of 212). Yet the odds ratio of Giacomini incompetence was 11.94 (7 of 33 over 3 of 169) in the presence of SSV reflux, and 11.67 (6 of 23 over 4 of 179) when both the great saphenous vein (proximal, proximal plus distal) and SSV were incompetent. CONCLUSION: Found in more than two thirds of limbs, the Giacomini vein has a complex anatomy that is linked vastly to the deep or superficial veins of the posteromedial thigh, but is unaffected by the anatomy of SSV termination and CEAP clinical class. Its presence proved insignificant to the extent, pattern, sites, and clinical severity of venous incompetence, yet the Giacomini vein was far less often susceptible to reflux than the saphenous trunks were. Routine Giacomini vein investigation is not justified in view of these findings. Investigation could be considered selectively in limbs with SSV incompetence, with or without great saphenous vein incompetence, supported by the high odds of concomitant Giacomini vein reflux.     

Joint Recommendations for Reporting Carotid Ultrasound Investigations in the United Kingdom

At present in the United Kingdom a number of different criteria are used to grade disease in carotid ultrasound investigations. One main cause of this has been the difference in the method of grading angiograms used in the NASCET and ECST large carotid surgery trials. It is desirable that all centres reporting carotid ultrasound investigations report to the same standard. This paper presents recommendations for the reporting of ultrasound investigations of the extra cranial arteries produced by a Joint Working Group formed between the Vascular Society of Great Britain and Ireland, and the Society for Vascular Technology of Great Britain and Ireland. The recommended criteria are based on the NASCET method of grading carotid bulb disease. Key recommendations include recording peak systolic velocity (PSV) and end-diastolic velocity (EDV) in both internal and distal common carotid arteries; measuring all velocities at a Doppler angle of 45–60°; the use of internal carotid PSV of >1.25 ms^?1 and >2.3 ms^?1 and a Peak Systolic Velocity Ratio of >2 and >4 to indicate >50% and >70% stenosis respectively; and the use of the St Mary's Ratio to grade >50% stenoses in deciles. General recommendations are also given for the acquisition, interpretation and reporting of the data.     

Interleukin-1 receptor antagonist and interleukin-1β-511 gene polymorphisms among Egyptian children with febrile seizures

Febrile seizures (FSs) are the most common form of childhood seizures. The higher levels of pro-inflammatory cytokines in children may induce seizures, and alternatively, higher levels of anti-inflammatory cytokines may act as a defense mechanism against seizures. We aimed to investigate whether interleukin (IL)-1β-511 C/T (pro-inflammatory cytokine) (rs16944) and IL-1 receptor antagonist (IL-1Ra) (an anti-inflammatory cytokine) gene polymorphisms could be used as markers for prediction of susceptibility to FSs. The current study included 22 patients with FSs and 22 normal control subjects. All patients were subjected to thorough history taking, full neurological examination, electroencephalography, and peripheral blood sampling for genotype analyses. Detection of IL-1Ra gene polymorphisms was done using polymerase chain reaction (PCR), while a restriction fragment length polymorphism analysis of the PCR products was used for the detection of IL-1β-511 C/T gene polymorphisms. The mean age of onset of first febrile seizures was 15.7 months. Eighteen (81.8 %) cases had the criteria of complex FSs. Frequencies of alleles C and T for IL-1β-511 were 26/44 and 18/44, respectively, in FS patients and 22/44 for both in the control subjects. The CC genotype was significantly more common in the FS patients than in the control group. The IL-1Ra-I homozygote was more frequent in patients with FSs than in healthy controls. The IL-1Ra homozygous I/I and IL-1β-511 CC gene polymorphisms are associated with a higher susceptibility to febrile seizures, which may be useful markers for predicting the development of febrile seizures.