2-Benzoyl-1-(2,4-dichloro­phen­yl)-3-phenyl­guanidine

In the title compound, C20H15Cl2N3O, a typical polysubstituted guanidine with normal geometric parameters, the torsion angles [C—N—C—O = 3.8 (2), N—C—N—C = −6.1 (2)°] indicate that the guanidine and carbonyl groups are almost coplanar, due to the pseudo-hexa­gonal ring formed by intra­molecular N—H⋯O hydrogen bonds. The crystal packing is stabilized by inter­molecular N—H⋯O hydrogen bonds, which link the mol­ecules into centrosymmetric dimers

Comparison of oral versus injectable vitamin-D for the treatment of nutritional vitamin-D deficiency rickets

OBJECTIVE: To assess the safety and acceptability of a single dose of vitamin-D versus the efficacy of injectable Vitamin-D versus oral vitamin-D. STUDY DESIGN: Case control. PLACE AND DURATION OF STUDY: It was carried out at the Department of Paediatrics, Kharadar General Hospital, Karachi, from August 2003 to April 2004. METHODOLOGY: Children of the age of 6 months to 3 years with clinical, biochemical and radiological evidence of vitamin- D deficiency rickets were included. The history, clinical examination, complete blood picture, serum calcium. Phosphorus, alkaline phosphatase and X-ray of wrist joint were done. The children were divided into two groups A and B. Group A was given oral vitamin-D and group B was given intramuscular injection of vitamin-D on the first day and then they were followed for two more visits at 30 and 90 days with clinical, biochemical and radiological examinations to assess the outcome. RESULTS: There were 50 confirmed cases of rickets in each group. The mean age was 10.9+5.1 months and 14.7+8.1 months in group A and B respectively. In these children, clinical features were weakness, difficulty in walking, frontal bossing, ribcage deformity and widening of wrist were seen. After one dose of vitamin-D (cholecalciferol), there was appreciable gain of weight and height and raised levels of alkaline phosphatase became normal during follow-up. Radiological florid rickets and non-florid rickets in both groups healed clinically during follow-up period. Oral and injectable forms of vitamin-D (cholecalciferol) were effective but injectable form was shown to be statistically significant. There were no undesirable side effects and both forms of treatment were well-tolerated

Infective endocarditis in patients with congenitally malformed hearts: characterization of the syndrome in a developing country

Cardiac surgery for correction or palliation of congenital cardiac disease in infancy and childhood remains a privilege that is rarely accessible to two-thirds of the world’s population. This imbalance has created a unique spectrum of illness in patients with underlying congenital cardiac disease and complicating infective endocarditis in developing countries, including Pakistan. In this study, we characterize endocarditis as seen in such patients presenting in Karachi. We reviewed retrospectively patients admitted to Aga Khan University with underlying congenitally malformed hearts and endocarditis between 1991 and 2004. We identified 48 patients with endocarditis according to the modified Duke Criterions, with just over half the cases (54%) classified as definite endocarditis. Of the patients, 23 (49%) patients were more than 16 years old. Uncorrected left-to-right-shunts, tetralogy of Fallot, and congenital mitral valvar disease were the most common underlying defects. Patients with cyanotic defects, particularly of the complex type, were underrepresented (4%). Only 11 (22.9%) of the patients had a previous palliative or corrective surgery. In one-third of the patients (16), streptococcal species were identified as the microbiologic cause of endocarditis, and 22 (45.8%) had culture-negative endocarditis. In contrast, Staphylococcus aureus and enterococci caused endocarditis in only one patient each. There were no differences in mortality or complications between cyanotic and acyanotic congenital defects. Surgery was performed in nine (18.7%) patients with endocarditis, and of these, 13 (27.1%) died. In contrast to the developed world, endocarditis in the developing countries, such as Pakistan, complicates uncorrected left-to-right shunts and tetralogy of Fallot, probably because patients with complex cyanotic defects fail to survive long after birth due to the lack of available surgery. Almost half of patients had culture-negative endocarditis, likely related to several factors

N-Benzoyl-N′,N′′-diphenyl­guanidinium chloride

In the title compound, C20H18N3O+·Cl−, the orientation of the aromatic rings around the planar CN3 + unit produces steric hindrance. As a consequence of this particular orientation of the guanidinium cation, hydrogen bonding is restricted to N—H⋯Cl and intra­molecular N—H⋯O hydrogen bonds within the discrete unit. The guanidinium and carbonyl groups are coplanar as a result of the six-membered ring formed by the N—H⋯O intra­molecular hydrogen bond. The dihedral angles between the guanidinium plane and the two phenyl rings are 62.31 (8) and 64.24 (8)°

INDIGO : better geomagnetic observatories where we need them

The INDIGO project aims to improve the global coverage of digital observatories by deploying digital magnetometer systems in: i) Observatories where existing analog recording equipment is in need of upgrading. ii) Newly established digital observatories. iii) Existing digital observatories for the purpose of quality control and redundancy. In implementing the project and selecting suitable sites, special attention is paid to parts of the Earth devoid of magnetic observatories, increasing the reliability and long-term operation of existing observatories and cost-effective use of local resources. The Poster reviews the current status of the project. We examine the different steps and initiatives taken since the initiation of INDIGO in 2004 and assess their effectiveness in achieving progress towards our aims of improving global coverage and enhanced data quality

Structural phase transition and opto-electronic properties of NaZnAs

In this study, we predict the structural phase transitions as well as opto-electronic properties of the filled-tetrahedral (Nowotny-Juza) NaZnAs compound. Calculations employ the full potential (FP) linearized augmented plane wave (LAPW) plus local orbitals (lo) scheme. The exchange-correlation potential is treated within the generalized gradient approximation of Perdew-Burke and Ernzerhof (GGA-PBE). In addition, Tran and Blaha (TB) modified Becke-Johnson (mBJ) potential is also used to obtain more accurate optoelectronic properties. Geometry optimization is performed to obtain reliable total energies and other structural parameters for each NaZnAs phase. In our study, the sequence of the structural phase transition on compression is Cu2Sb-type ? ß ? a phase. NaZnAs is a direct (G-G) band gap semiconductor for all the structural phases. However, compared to PBE-GGA, the mBJ approximation reproduces better fundamental band gaps. Moreover, for insight into its potential for photovoltaic applications, different optical parameters are studied

Development of in vitro-in vivo correlation for nimesulide loaded ethylcellulose microparticles

A predictive in vitro-invivo correlation (IVIVC) can empower in vitro dissolution as a surrogate for in vivo bioavailability / bioequivalence. IVIVCs can decrease regulatory burden by decreasing the number of biostudies required in support of a drug product. The present study concerns the establishment of in vitro-in vivo correlation for three different sustained release nimesulide loaded ethylcellulose microparticulate formulations (M1, M2 and M3) and conventional tablet (100 mg Nimaran®-Novartis, Pakistan). In vitro dissolution study was conducted in phosphate buffer pH 6.8 stirred at 50 rpm and 37 ± 0.5ºC. A validated HPLC method was adopted to conduct bioavailability studies in young healthy human volunteers. Ultimately IVIVC of prepared microparticles and conventional tablet was established using Wagner-Nelson method. M1 and M2 formulations and Nimaran® exhibited good linear IVIVC (R2 = 0.9220, 0.9124, 0.8728, respectively) as compared to M3 (R2 = 0.9449). The results substantiate the success of this mathematical simulation study encourage researchers to conduct biowaiver studies for other BCS class II drugs.Colegio de Farmacéuticos de la Provincia de Buenos Aire

A comparative analysis of toluidine blue with frozen section in oral squamous cell carcinoma

Background:Surgical excision of the primary tumor with safe margins remains the mainstay of treatment for oral cavity squamous cell carcinoma (OSCC). The standard of care for assessment of intraoperative margins is frozen section histopathology. Unfortunately the facility is not available at most centers in limited resource countries. Toluidine blue, a metachromatic dye, has been well described in clinical identification of malignant and premalignant lesion in the oral cavity. Considering this we decided to explore intraoperative use of toluidine blue staining, in comparison with frozen sections, for the assessment of tumor-free margins. Methods: After obtaining clearance from the in-house ethical review committee, a prospective study was conducted at Aga Khan University Hospital, Karachi, from August 15, 2009 to March 14, 2010. A sample of 56 consenting Patients with biopsy-proven OSCC were included in the study, giving us 280 tumor margins. Margins were analyzed using toluidine blue staining and frozen section histopathology. A receiver operator curve (ROC) was then applied to compare assessment of margin status by toluidine blue and frozen section. Results: Of the 280 examined margins 11 stained positive with toluidine blue, three were positive on frozen section biopsy, and three were positive on final histopathology. Toluidine blue staining had sensitivity and specificity of 100% and 97%, respectively. The diagnostic accuracy of toluidine blue was found to be 97.1% with a positive predictive value (PPV) of 27.2% and a negative predictive value (NPV) of 100%. Conclusions: Toluidine blue can be used as an effective screening modality for the assessment of intraoperative margins in resource limited environments and reducing the number of frozen section biopsies performed. Further by providing real-time clinical information within minutes it can reduce indirect costs such as operating room time. It may also be used as an ad hoc for frozen section biopsies where frozen section facilities are available