Alvarado versus RIPASA Score for the Diagnosis of Acute Appendicitis.

The aim of the present study was to compare the sensitivity between Alvarado and RIPASA score for the diagnosis of acute appendicitis patients. A comparative study was conducted in the Dhaka National Medical College Hospital, Bangladesh from July 2015 to December 2015. The study was approved by the institutional ethical committee. Most of the appendicitis patients belonged to the between 21-30 years which was 64(32%). Male appendicitis patients (52%) are more than the female patients (48%). Majority of the patients (69%) complains pain occurs in the Right iliac fossa. Sensitivity of Alvarado scores was 81.60%, specificity 74.58%, accuracy 79.35%, positive and negative predictive values were 87.18% and 65.67% respectively. RIPASA score's sensitivity was 85.6%, specificity 69.49%, accuracy 80.40%, positive and negative predictive values were 85.60% and 85.60% respectively. This study reported that RIPASA score is significantly shown higher diagnostic accuracy then that Alvarado score.

Pattern of Pulmonary Involvement and Outcome of Aspiration Pneumonia in Patients with Altered Consciousness Admitted in Dhaka Medical College Hospital.

Aspiration is well recognized as a cause of pulmonary disease and is not uncommon in patients with altered consciousness.The mortality rate of aspiration pneumonia is approximately 1% in outpatient setting and upto 25% in those requiring hospitalization. This study was done to see the pattern of pulmonary involvement and outcome of aspiration pneumonia in patients with altered consciousness admitted in medicine department of a tertiary care hospital in our country. This was a prospective observational study conducted among the 52 adult patients of aspiration pneumonia with altered consciousness admitted in the medicine department of Dhaka Medical College Hospital (DMCH), during June 2010 to December 2010. Aspiration pneumonia was confirmed by clinical examination and laboratory investigations. Hematologic measurements (TC of WBC, Hb%, ESR, platelet count), chest X-ray, blood gas analysis, blood urea, creatinine and random blood sugar, sputum for Gram staining, sputum for culture sensitivity and blood culture were done in all patients.Assessment of altered conscious patient was done by application of the Glasgow Coma Scale. Case record forms with appropriate questionnaire were filled for all patients. The mean±SD age was 57.42±13.63 years with ranged from 25 to 90 years. Out of 52 patients, 37(71.15%) patients were male and 15(28.85%) patients were female. Following aspiration 76.92% patients developed pneumonitis, 13.46% patients developed lung abscess and only 9.62% patients developed ARDS. Most (33) of the patients had opacity in right lower zone and 13 patients had opacity in the left lower zone, 6 patients had opacity in right mid zone. Only 10 patients had opacity in both lower zones. In this study overall mortality rate was 23%. If only one lobe was involved radiologically, mortality was 8.33%. If two or more lobes on one or both sides were involved, mortality was in the range of 25-91%.

Significance of weak interactions in imidazolium picrate ionic liquids: spectroscopic and theoretical studies for molecular level understanding.

The effects of interionic hydrogen bonding and π-π stacking interactions on the physical properties of a new series of picrate anion based ionic liquids (ILs) have been investigated experimentally and theoretically. The existence of aromatic (C2-HO) and aliphatic (C7-HO-N22 and C6-HO-N20) hydrogen bonding and π-π stacking interactions in these ILs has been observed using various spectroscopic techniques. The aromatic and aliphatic C-HO hydrogen bonding interactions are found to have a crucial role in binding the imidazolium cation and picrate anion together. However, the π-π stacking interactions between two successive layers are found to play a decisive role in tight packing in ILs leading to differences in physical properties. The drastic difference in the melting points of the methyl and propyl derivatives (mmimPic and pmimPic respectively) have been found to be primarily due to the difference in the strength and varieties of π-π stacking interactions. While in mmimPic, several different types of π-π stacking interactions between the aromatic rings (such as picrate-picrate, picrate-imidazole and imidazolium-imidazolium cation rings) are observed, only one type of π-π stacking interaction (picrate-picrate rings) is found to exist in the pmimPic IL. NMR spectroscopic studies reveal that the interaction of these ILs with solvent molecules is different and depends on the dielectric constant of the solvent. While an ion solvation model explains the solvation in high dielectric solvents, an ion-pair solvation model is found to be more appropriate for low dielectric constant solvents. The enhanced stability of these investigated picrate ILs compared with that of inorganic picrate salts under high doses of γ radiation clearly indicates the importance of weak interionic interactions in ILs, and also opens up the possibility of the application of picrate ILs as prospective diluents in nuclear separation for advanced fuel cycling process.

Sphincter saving surgery is the standard procedure for treatment of low rectal cancer.

Carcinoma rectum is a challenging problem both for the developed and underdeveloped countries. Colorectal cancer accounts for 9% of all cancer deaths (49,920) in 2009 in USA. Carcinoma involving the lower part of the rectum is now successfully managed by sphincter saving surgery with less morbidity and uneventful recovery. To observe the objective, subjective and functional outcome of the patients suffering from cancer of the lower third of the rectum managed by surgical intervention with preservation of sphincter. A comparative study was carried out on 54 patients with low rectal cancer who underwent ultra-low anterior resection in the department of surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka from January 2009 to December 2010. Patients were divided into two groups depending on the tumor distance from anal verge. Thirty one (57%) patients were in Group A (Experimental) where tumor distance was 5cm from anal verge and upper 1cm of anal sphincter was sacrificed during surgical intervention. Twenty three (43%) patients were in Group B (Control) where tumor distance was 6cm from anal verge and whole length (4cm) of anal sphincter was preserved during surgical intervention. Functional integrity of anal sphincter was assessed between these two groups of patients following surgery. The mean age of the patients was 45.96±14.41 years. During surgery, ultra low anterior resection was performed to remove the tumor in all patients and for anastomosis double stapling technique was performed in 52(96%) patients and hand sewn technique was performed in 2(4%) patients irrespective of tumor distance from anal verge. Covering ileostomy was fashioned in all but one patient. During post-operative follow up anal sphincter muscle tone, anal sphincter function (Anal continence, p = 0.54), Quality of life (Social life, p = 0.54; Professional life, p = 0.23; House work and Need a diaper, p = 0.54) were not significantly impaired in both groups. Functional outcome of anal sphincter muscle and quality of life was not impaired in comparison to general population after low rectal cancer surgery.

Diagnosis of breast lump by fine needle aspiration cytology and mammography.

Breast carcinoma is the most common malignant tumour and the leading cause of death from cancer in women. A large number of patients in Bangladesh have been suffering from breast cancer. Now-a-days, Fine needle aspiration cytology (FNAC) is being performed as a pre-operative test to evaluate breast lump. FNAC is cost effective and can prevent unnecessary surgery. As FNAC became more reliable in diagnosing malignancy and thereby the use of frozen-section histology had been reduced by about 80%. But erroneous diagnosis is more common with FNAC than with histopathology. However, mammography can identify breast cancers too small to palpate on physical examination and theoretically beneficial to diagnose even noninvasive lesions. Present study aimed to see the accuracy of FNAC and mammography in the diagnosis of palpable breast lumps and to study their correlation. In this study 222 patients were included in the study and FNAC was done in all the patients. Mammography was done in 112 cases. Among these 112 patients 32 cases were found malignant. Histopathology was done in total 89 cases. Among 112 patients who were underwent mammography only 43 were found for histopathology. Finally, 36 cases were found malignant. Fibroadenoma is mostly found in below 20 years group and malignancy is mostly occurring in older age group. Mammography shows total 8 false positive and 5 false negative cases. FNAC shows only 1 false positive and 1 false negative case. On analysis mammography showed 82.76% sensitivity, 90.36% specificity, 75% Positive predictive value (PPV), 93.75% Negative predictive value (NPV) and 88.39% accuracy. FNAC showed 97.22% sensitivity, 99.46% specificity, 97.220% PPV, 99.46% NPV and 99.095% accuracy. Mammography was found to be less sensitive, specific and accurate in the diagnosis of breast lump though there is highly significant correlation among them. However, the study has shown a much higher performance of FNAC than other previous studies indicating the improved skill in cytological diagnosis to a satisfactory level.

Theoretical studies on the structure and detonation properties of amino-, methyl-, and nitro-substituted 3,4,5-trinitro-1H-pyrazoles.

In this study, 3,4,5-trinitro-1H-pyrazole (R20), 3,4,5-trinitro-1H-pyrazol-1-amine (R21), 1-methyl-3,4,5-trinitro-1H-pyrazole (R22), and 1,3,4,5-tetranitro-1H-pyrazole (R23) have been considered as potential candidates for high-energy density materials by quantum chemical treatment. The geometric and electronic structures, band gap, thermodynamic properties, crystal density and detonation properties were studied using density functional theory at the B3LYP/aug-cc-pVDZ level. The calculated energy of explosion, density, and detonation performance of model compounds are comparable to 1,3,5-trinitro-1,3,5-triazinane (RDX), and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). Atoms-in-molecules (AIM) analyses have also been carried to understand the nature of intramolecular interactions and the strength of trigger bonds.

Synthesis and characterization of 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine (BTATz): novel high-nitrogen content insensitive high energy material.

This paper reports the synthesis, characterization and thermolysis studies of 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine (BTATz) and 3-(1H-1,2,3,4-tetrazol-5-ylamino)-6-(3,5-dimethyl-pyrazol-1-yl)-s-tetrazine monohydrate (TADPTz). The synthesized BTATz and TADPTz have been characterized by spectroscopic techniques and the data obtained confirm their structure. TGA and DSC results suggested that BTATz decomposes in the range 265-350 degrees C and TADPTz in the range 245-275 degrees C respectively. The calculated energy of activation of BTATz and TADPTz is 212.69 and 257.29kJ/mol respectively. The experimentally determined DeltaH(f) value matches with theoretically computed heat of explosion. The computed volume of gases indicates that they can find application in gas generating compositions.

Suitability of nitrogen rich compounds for gun propellant formulations.

This paper reports the suitability of a novel nitrogen rich compound, guanidinium-5-aminotetrazolate for RDX-based high-energy gun propellant formulations in respect of flame temperature as well as the burning rate characteristics. It has been found that the partial replacement of RDX with guanidinium-5-amino tetrazolate at the rate of five parts decreases the flame temperature of the propellant by about 120 K without adversely affecting the burning rate characteristics, i.e. linear rate of burning co-efficient and pressure exponent.

Environmentally compatible next generation green energetic materials (GEMs).

This paper briefly reviews the literature work reported on the environmentally compatible green energetic materials (GEMs) for defence and space applications. Currently, great emphasis is laid in the field of high-energy materials (HEMs) to increase the environmental stewardship along with the deliverance of improved performance. This emphasis is especially strong in the areas of energetic materials, weapon development, processing, and disposal operations. Therefore, efforts are on to develop energetic materials systems under the broad concept of green energetic materials (GEMs) in different schools all over the globe. The GEMs program initiated globally by different schools addresses these challenges and establishes the framework for advances in energetic materials processing and production that promote compliance with environmental regulations. This review also briefs the principles of green chemistry pertaining to HEMs, followed by the work carried out globally on environmentally compatible green energetic materials and allied ingredients.

DomNet: protein domain boundary prediction using enhanced general regression network and new profiles.

The accurate and stable prediction of protein domain boundaries is an important avenue for the prediction of protein structure, function, evolution, and design. Recent research on protein domain boundary prediction has been mainly based on widely known machine learning techniques. In this paper, we propose a new machine learning based domain predictor namely, DomNet that can show a more accurate and stable predictive performance than the existing state-of-the-art models. The DomNet is trained using a novel compact domain profile, secondary structure, solvent accessibility information, and interdomain linker index to detect possible domain boundaries for a target sequence. The performance of the proposed model was compared to nine different machine learning models on the Benchmark_2 dataset in terms of accuracy, sensitivity, specificity, and correlation coefficient. The DomNet achieved the best performance with 71% accuracy for domain boundary identification in multidomains proteins. With the CASP7 benchmark dataset, it again demonstrated superior performance to contemporary domain boundary predictors such as DOMpro, DomPred, DomSSEA, DomCut, and DomainDiscovery.

Studies on thermal decomposition mechanism of CL-20 by pyrolysis gas chromatography-mass spectrometry (Py-GC/MS).

The thermal decomposition study of CL-20 (hexanitrohexaazaisowurtzitane) using pyrolysis GC/MS was carried out mainly by electron impact (EI) mode. Chemical ionization (CI) mode was used for further confirmation of identified species. Mass spectrum of CL-20 decomposition products predominantly revealed fragments with m/z 81 and 96 corresponding to C(4)H(5)N(2)(+) and C(4)H(4)N(2)O(+) ions, respectively. The total ion chromatogram (TIC) of CL-20 pyrolysis shows peak within first 2 min due to the presence of low molecular weight gases. Peaks corresponding to several other products were also observed including the atmospheric gases. Cyanogen formation (C(2)N(2), m/z 52) observed to be enriched at the scan number 300-500. The low molecular mass range decomposition products formed by cleavage of C-N ring structure were found in majority. Additional structural information was sought by employing chemical ionization mode. The data generated during this study was instrumented in determining decomposition pathways of CL-20.

Role of inorganic additives on the ballistic performance of gun propellant formulations.

This paper explores the possibility of increasing the ballistic performance of gun propellant with the addition of inorganic additives viz. aluminium and ammonium perchlorate. Compositions based on propellant NQ containing additional aluminium and ammonium perchlorate in different parts were studied theoretically and experimentally. Performance in respect of ballistic parameters, sensitivity, thermal characteristics, thermal stability and mechanical properties are evaluated and compared with that of the conventional triple base propellant NQ. Experimental data on comparative study indicate that the compositions containing aluminium and ammonium perchlorate are superior to propellant NQ in respect of energy.

Study of oral itraconazole and terbinafine pulse therapy in onychomycosis.

In this open, randomized and comparative study, the safety and efficacy of systemic intermittent itraconazole and terbinafine was examined in 30 patients with onychomycosis. The patient with positive mycological culture and also the patients with positive microscopy and negative culture were investigated. Patients were randomly assigned: 15 patients in each group received either 200mg itraconazole or 250 mg terbinafine twice daily during the first week of a 4 weeks cycle. The treatment duration was 16 weeks and was followed-up for 36 weeks. Both the treatment regimen showed significant reduction in onychomycosis affected areas after 8 weeks and maximum reduction was observed at the end of 36 weeks. At the end point of the follow-up period, the clinical cure rates (no residual deformity or with some deformity) were 86.7% in the itraconazole group and 100% in the terbinafine group. The mycological cure rates were 86.7% and 100% respectively. However, no statistically significant differences between the treatment groups were seen in clinical, mycological (P= 0.864) and severity assessment (P= 0.220). Nausea, abdominal cramp, headache, back pain and flu like syndrome are the adverse effects more frequently reported. At least one adverse effect was reported by 17 patients, of them 12 belonged to itraconazole group and 5 to terbinafine group and the difference was statistically significant (P= 0.027). The overall therapeutic effectiveness, safety and cost affectivity were in favor of Terbinafine pulse therapy.

1,3,3-Trinitroazetidine (TNAZ), a melt-cast explosive: synthesis, characterization and thermal behaviour.

1,3,3-Trinitroazetidine (TNAZ) has been prepared at a laboratory scale in HEMRL. The structure of the compound has been confirmed by IR, NMR, mass, elemental analysis and by X-ray crystallography. HPLC technique has been employed to confirm the purity of TNAZ (>99%). The compound is further characterized by thermal techniques and is found to undergo limited decomposition at its melting point. Small scale sensitivity tests have also been carried out and the results show that TNAZ is significantly more sensitive to mechanical stimuli than TNT.

A review of advanced high performance, insensitive and thermally stable energetic materials emerging for military and space applications.

Energetic materials used extensively both for civil and military applications. There are continuous research programmes worldwide to develop new materials with higher performance and enhanced insensitivity to thermal or shock insults than the existing ones in order to meet the requirements of future military and space applications. This review concentrates on recent advances in syntheses, potential formulations and space applications of potential compounds with respect to safety, performance and stability.

Cost-effective synthesis of 5,7-diamino-4,6-dinitrobenzofuroxan (CL-14) and its evaluation in plastic bonded explosives.

5,7-Diamino-4,6-dinitrobenzofuroxan (CL-14) has been synthesized by a cost-effective method. CL-14 was characterized by spectral data (IR, NMR and mass) and elemental analysis. The compound was evaluated in plastic bonded explosives (PBX) using polyurethane (PU) as binder. The thermal, mechanical and explosive properties of PBX composition from preliminary tests are also reported. Good thermal stability as well as good insensitiveness are indicated.

Synthesis, characterization and thermal studies of 2-oxo-1,3,5-trinitro-1,3,5-triazacyclohexane (Keto-RDX or K-6).

2-Oxo-1,3,5-trinitro-1,3,5-triazacyclohexane (Keto-RDX or K-6), the most powerful energetic material among nitrourea explosives, has been prepared and scaled up at laboratory level. The identity and purity of the product are tested by elemental analysis, IR, NMR, mass and HPLC techniques. Thermal response and sensitivity experiments on K-6 are also described. The data on sensitivity shows that K-6 can be utilised practically only in phlegmatized form.

Synthesis and characterisation of 4-picrylamino-2,6-dinitrotoluene (PADNT): a new insensitive explosive.

A chemoselective reductive method has been achieved for the preparation of 4-picrylamino-2,6-dinitrotoluene (PADNT), a new insensitive energetic material which has been characterised by spectral data and elemental analysis. Some explosive properties of the compound have also been determined and the results indicate that PANDT is quite safe to impact and friction.

Important aspects of behaviour of organic energetic compounds: a review.

The importance of a prediction tool increases with greater relevance for synthesis, performance and vulnerability predictions. Some important aspects of performance behaviour and their theoretical calculations, which are indispensable in recognising energetic molecules of interest, are described here. This review also discusses on factors influencing sensitivity and overall stabilities of organic energetic compounds especially on nitroaromatics and nitramines, and exceptions to this relationship suggest other factors playing roles in specific instances.

Studies on characterisation and thermal behaviour of 3-amino-5-nitro-1,2,4-triazole and its derivatives.

3-Amino-5-nitro-1,2,4-triazole (ANTA) and its derivatives have been prepared in order to carry out the systematic studies on structural aspects, explosive and thermal behaviour. Thermal studies were carried out for ANTA and 4,6-bis-(3-amino-5-nitro-1H-1,2,4-triazole-1-yl)-5-nitropyrimidine (DANTNP) by thermogravimetry (TG), differential thermal analysis (DTA), differential scanning calorimeter (DSC) and manometric thermal analysis. The results show that (DANTNP) is more thermally stable than ANTA when compared in terms of activation energy.