Age of puberty in Iranian girls living in Tehran

The aim of this study was to determine the age of appearance of secondary sexual characteristics in Iranian girls living in Tehran. A cross-sectional study was conducted between 2003 and 2004 on 1420 6–17-year-old females in different parts of Tehran. Data were collected on the basis of a multistage probability sampling. Secondary sexual characteristics were evaluated by inspection and palpation, and were recorded according to Tanner staging. The subjects were asked about the occurrence of menarche and the age of its onset. Generalized additive logistic modelling was used for the analysis of data. The median age (percentile 10–percentile 90) of Tanner 2 of breast development (B2) and Tanner 2 of pubic hair growth (P2) among 1136 girls was 9.74 years (8.23–11.94) and 10.49 years (8.86–12.17), respectively. The ages of the 2.5 percentile for B2 and P2 were 7.42 and 7.03 years, respectively, so the onset of puberty at <7 years and 5 months is considered precocious in this population. The median age of menarche in 399 girls was 12.68 years (11.27–15.96).     

COVID-19 or not COVID-19? Compared characteristics of patients hospitalized for suspected COVID-19

European Journal of Clinical Microbiology & Infectious Diseases - During an epidemic period, we compared patients hospitalized for initial suspicion of COVID-19 but for whom an alternative...     

Cone Beam Computed Tomography Analysis of Sphenoid Sinus Pneumatization and Relationship with Neurovascular Structures

BackgroundThe sphenoid sinus is considered as the most variable pneumatized structure of the skull.PurposeThe aim of the present study was to determine the prevalence of the Onodi cell as well as to evaluate the relationship between the sphenoid sinus type of pneumatization and the presence of surrounding neurovascular protrusion using cone beam computed tomography (CBCT).MethodsThe CBCT images of 500 patients/996 sides [203 males (40.6%) and 297 females (59.4%)] were analyzed in this study. The type of sphenoid sinus pneumatization, prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusion and dehiscence, and also the frequency of Onodi cell were assessed.ResultsThe percentages of the conchal, presellar, sellar, postsellar (a), and postsellar (b) types of pneumatization were 1%, 11.5%, 35.5%, 38.9%, and 13.1%, respectively. The more the sphenoid sinuses pneumatized, the greater the frequency of ON and ICA protrusion and dehiscence of their wall to the sinus. The prevalence of Onodi cell was 38.8%. A significant correlation was found between ON dehiscence and the presence of Onodi cells.ConclusionThe present study demonstrated a significant relationship between the sinus type and frequency of neurovascular protrusions. Therefore, the sphenoid sinus extent of pneumatization might be useful in predicting the risk of iatrogenic damage to the surrounding structures.     

A novel isoform of the B cell tyrosine kinase BTK protects breast cancer cells from apoptosis

Tyrosine kinases orchestrate key cellular signaling pathways and their dysregulation is often associated with cellular transformation. Several recent cases in which inhibitors of tyrosine kinases have been successfully used as anticancer agents have underscored the importance of this class of proteins in the development of targeted cancer therapies. We have carried out a large‐scale loss‐of‐function analysis of the human tyrosine kinases using RNA interference to identify novel survival factors for breast cancer cells. In addition to kinases with known roles in breast and other cancers, we identified several kinases that were previously unknown to be required for breast cancer cell survival. The most surprising of these was the cytosolic, nonreceptor tyrosine kinase, Bruton's tyrosine kinase (BTK), which has been extensively studied in B cell development. Down regulation of this protein with RNAi or inhibition with pharmacological inhibitors causes apoptosis; overexpression inhibits apoptosis induced by Doxorubicin in breast cancer cells. Our results surprisingly show that BTK is expressed in several breast cancer cell lines and tumors. The predominant form of BTK found in tumor cells is transcribed from an alternative promoter and results in a protein with an amino‐terminal extension. This alternate form of BTK is expressed at significantly higher levels in tumorigenic breast cells than in normal breast cells. Since this protein is a survival factor for these cells, it represents both a potential marker and novel therapeutic target for breast cancer. © 2013 Wiley Periodicals, Inc.     

Oxygen Desaturation in Daily Life and During a Laboratory-Based Protocol of Activities of Daily Living in COPD: Is There Relationship?

Purpose

To analyze the relationship between oxygen desaturation episodes during a laboratory-based ADL protocol and in real-life routine in patients with stable chronic obstructive pulmonary disease (COPD).

Methods

Twenty patients with stable COPD (12 men, 70 ± 7 years, FEV₁% 54 ± 15 predicted) with no indication for long-term oxygen therapy (LTOT) were submitted to assessments including ADL performance by the Londrina ADL Protocol (LAP) and level of physical activity in daily life, both while submitted to simultaneous activity and pulse oximeter monitoring.

Results

Episodes of desaturation ≥ 4% (ED ≥ 4%) during the LAP were correlated both with ED ≥ 4% in daily life (r = 0.45) and number of episodes of SpO₂ under 88% (ED < 88%) in daily life (r = 0.59). ED < 88% during the LAP was also correlated with ED < 88% in daily life (r = 0.51), explaining 43% of its variance.

Conclusion

In stable patients with COPD and no indication of LTOT, episodes of desaturation during a lab-based ADL protocol are moderately related to episodes of desaturation in daily (real) life, especially those episodes under 88%.

     

Consensus-derived structural determinants of the ankyrin repeat motif

The ankyrin repeat is one of the most common, modular, protein-protein interaction motifs in nature. To understand the structural determinants of this family of proteins and extract the consensus information that defines the architecture of this motif, we have designed a series of idealized ankyrin repeat proteins containing one, two, three, or four repeats by using statistical analysis of approximately 4,000 ankyrin repeat sequences from the PFAM database. Biophysical and x-ray crystallographic studies of the three and four repeat constructs (3ANK and 4ANK) to 1.26 and 1.5 A resolution, respectively, demonstrate that these proteins are well-folded, monomeric, display high thermostability, and adopt a very regular, tightly packed ankyrin repeat fold. Mapping the degree of amino acid conservation at each position on the 4ANK structure shows that most nonconserved residues are clustered on the surface of the molecule that has been designated as the binding site in naturally occurring ankyrin repeat proteins. Thus, the consensus amino acid sequence contains all information required to define the ankyrin repeat fold. Our results suggest that statistical analysis and the consensus sequence approach can be used as an effective method to design proteins with complex topologies. These generic ankyrin repeat proteins can serve as prototypes for dissecting the rules of molecular recognition mediated by ankyrin repeats and for engineering proteins with novel biological functions.