Urbanization and green space dynamics in Greater Dhaka, Bangladesh

Green space is particularly indispensable for proper functioning of the ecosystem in an urban environment. This study was an attempt to dynamically map and monitor green spaces in Greater Dhaka of Bangladesh. Both primary and secondary data were acquired to document the spatial–temporal dynamics of green spaces in the study area. Using a supervised classification algorithm, multi-temporal land use/cover data were extracted from a set of satellite images. A number of spatial metrics were employed to understand the landscape condition in a multi-temporal manner. In addition, 50 key informants along with focus group discussion and observation techniques were used to document existing management aspects of green spaces and their conservation policies. The analysis revealed that green spaces in Greater Dhaka are rapidly disappearing over the course of time even though they provide a number of natural, economic and social benefits. The disappearance of green spaces was primarily attributed to a rapid increase in the urban population, mainly driven by rural–urban migration. As a result, the landscape became highly fragmented and less connected. A substantial reduction of green patches is also leading to deterioration of the ecological condition of the landscape. The drastic reduction of green spaces in Greater Dhaka has been attributed to a lack of policy, low political motivation, and poor management. In order to ensure sustainability of green spaces and proper functioning of the city’s ecosystem, there is an urgent need for strategic green space planning.     

In vivo antipyretic,antiemetic, in vitro membrane stabilization,antimicrobial, and cytotoxic activities of different extracts from Spilanthes paniculata leaves

Background

The study was conducted to evaluate the in vitro antimicrobial activity, cytotoxic, and membrane stabilization activities, and in vivo antiemetic and antipyretic potentials of ethanolic extract, n-hexane and ethyl acetate soluble fractions of Spilanthes paniculata leaves for the first time widely used in the traditional treatments in Bangladesh.

Results

In antipyretic activity assay, a significant reduction (P < 0.05) was observed in the temperature in the mice tested. At dose 400 mg/kg-body weight, the n-hexane soluble fraction showed the effect (36.7 ± 0.63°C ) as like as the standard (dose 150 mg/kg-body weight) after 5 h of administration. Extracts showed significant (P < 0.001) potential when tested for the antiemetic activity compared to the standard, metoclopramide. At dose 50 mg/kg-body weight, the standard showed 67.23% inhibition, whereas n-hexane and ethyl acetate soluble fractions showed 37.53% and 24.93% inhibition of emesis respectively at dose 400 mg/kg-body weight. In antimicrobial activity assay, the n-hexane soluble fraction (400 μg/disc) showed salient activity against the tested organisms. It exerts highest activity against Salmonella typhi (16.9 mm zone of inhibition); besides, crude, and ethyl acetate extracts showed resistance to Bacillus cereus and Bacillus subtilis, and Vibrio cholera respectively. All the extracts were tested for lysis of the erythrocytes. At the concentration of 1mg/ml, ethanol extract, and n-hexane and ethyl acetate soluble fractions significantly inhibited hypotonic solution induced lysis of the human red blood cell (HRBC) (27.406 ± 3.57, 46.034 ± 3.251, and 30.72 ± 5.679% respectively); where standard drug acetylsalicylic acid (concentration 0.1 mg/ml) showed 77.276 ± 0.321% inhibition. In case of heat induced HRBC hemolysis, the plant extracts also showed significant activity (34.21 ± 4.72, 21.81 ± 3.08, and 27.62 ± 8.79% inhibition respectively). In the brine shrimp lethality bioassay, the n-hexane fraction showed potent (LC₅₀ value 48.978 μg/ml) activity, whereas ethyl acetate fraction showed mild (LC₅₀ value 216.77 μg/ml) cytotoxic activity.

Conclusions

Our results showed that the n-hexane extract has better effects than the other in all trials. In the context, it can be said that the leaves of S. paniculata possess remarkable pharmacological effects, and justify its folkloric use as antimicrobial, antipyretic, anti-inflammatory, and antiemetic agent. Therefore, further research may be suggested to find possible mode of action of the plant part.     

Effects of temperature on protein structure and dynamics: X-ray crystallographic studies of the protein ribonuclease-A at nine different temperatures from 98 to 320 K.

Structures using X-ray diffraction data collected to 1.5-A resolution have been determined for the protein ribonuclease-A at nine different temperatures ranging from 98 to 320 K. It is determined that the protein molecule expands slightly (0.4% per 100 K) with increasing temperature and that this expansion is linear. The expansion is due primarily to subtle repacking of the molecule, with exposed and mobile loop regions exhibiting the largest movements. Individual atomic Debye-Waller factors exhibit predominantly biphasic behavior, with a small positive slope at low temperatures and a larger positive slope at higher temperatures. The break in this curve occurs at a characteristic temperature of 180-200 K, perhaps indicative of fundamental changes in the dynamical structure of the surrounding protein solvent. The distribution of protein Debye-Waller factors is observed to broaden as well as shift to higher values as the temperature is increased.     

Feasibility of Provider-Initiated HIV Testing and Counselling of Tuberculosis Patients Under the TB Control Programme in Two Districts of South India

Background

Provider-initiated HIV testing and counselling (PITC) is internationally recommended for tuberculosis (TB) patients, but the feasibility, effectiveness, and impact of this policy on the TB programme in India are unknown. We evaluated PITC of TB patients across two districts in India considered to have generalized HIV epidemics, Tiruchirappalli (population 2.5 million) and Mysore (population 2.8 million).

Methodology/Principal Findings

Starting June 2007, healthcare providers in both districts were instructed to ascertain HIV status for all TB patients, and refer those with unknown HIV status to the nearest Integrated Counselling and Testing Centre (ICTC)—often in the same facility—for counselling and voluntary HIV testing. All TB patients registered from June 2007 to March 2008 were followed prospectively. Field investigators assessed PITC practices and abstracted data from routine TB programme records and HIV counselling registers to determine the proportion of TB patients appropriately evaluated for HIV infection. Patient records were traced to determine the efficiency of referral links to HIV care and antiretroviral treatment (ART). Between July 2007 and March 2008, 5299 TB patients were registered in both study districts. Of the 4701 with unknown HIV status at the time of TB treatment initiation, 3368 (72%) were referred to an ICTC, and 3111 (66%) were newly tested for HIV. PITC implementation resulted in the ascertainment of HIV status for 3709/5299 (70%) of TB patients, and detected 200 cases with previously undiagnosed HIV infection. Overall, 468 (8.8%) of all registered TB patients were HIV-infected; 177 (37%) were documented to have also received any ART.

Conclusions

With implementation of PITC in India, HIV status was successfully ascertained for 70% of TB patients. Previously undiagnosed HIV-infection was detected in 6.4% of those TB patients newly tested, enabling referral for life-saving anti-retroviral treatment. ART uptake, however, was poor, suggesting that PITC implementation should include measures to strengthen and support ART referral, evaluation, and initiation.     

A human cDNA encoding the small subunit of RNA polymerase II transcription factor SIII

A full-length cDNA encoding a human homolog of the 15-kDa subunit (p15) of RNA polymerase II elongation factor SIII was isolated and sequenced. Comparison of the open reading frames of the human p15 cDNA and the previously characterized rat p15 cDNA [Garrett et al., Proc. Natl. Acad. Sci. USA 91 (1994) 5237-5241] indicates that they encode identical proteins and are 93% conserved in nucleotide sequence.     

Isolation of the opioid peptide Leu-Val-Val-hemorphin-7 from bronchoalveolar lavage fluid of a patient with non-small cell lung cancer

The decapeptide Leu-Val-Val-Tyr-Pro-Trp-Thr-Gln-Arg-Phe was isolated in high yield (1.5 nmol/ml) from bronchoalveolar lavage (BAL) fluid from a patient with an adenocarcinoma of the lung. This peptide, termed LVV-hemorphin-7 represents residues 32-41 of the beta-chain of hemoglobin and has been shown to be an endogenous ligand for opioid receptors. The N-terminal flanking peptide of LVV-hemorphin-7 [residues (1-31) of hemoglobin beta-chain] was also isolated in high yield. Neither peptide was detected in BAL fluid from the tumor-free lung of the same patient or from patients with non-neoplastic inflammatory lung disease. LVV-hemorphin-7 was not identified in BAL fluid from seven additional patients with non-small cell lung cancer, indicating that the formation of the peptide is unlikely to be of any diagnostic significance. However, the ability of LVV-hemorphin-7 to inhibit angiotensin-converting enzyme suggests that its formation may be of pathophysiological significance in the regulation of tumor blood flow in certain patients.     

Lack of an association between candidate gene loci and idiopathic generalized epilepsy in Kuwaiti Arab children

Summary Idiopathic generalized epilepsies (IGEs) are the most common types of epilepsy in childhood and adolescence. A variety of data suggest that IGEs have a predominant genetic etiology. Recently, a number of gene mutations have been found to be associated with various types of epilepsy in mainly the Caucasian populations. The objective of this study was to investigate the association of three different candidate genes with IGE in Kuwaiti Arab children. This study includes 123 Kuwaiti patients with a confirmed diagnosis of epilepsy. Most of the patients have had a diagnostic EEG with generalized spike-wave discharges (GSWs). All patients were evaluated by using a validated seizure questionnaire. The clinical type of epilepsy was determined by a trained neurologist/pediatrician. The study also include 100 controls, the control subjects were children which did not have any history of neurological disorders. Blood samples were collected from all patients and control subjects after taking informed consent. DNA was isolated and analyzed by molecular methods. A FokI polymorphism in neuronal nicotinic acetylcholine receptor alpha-4 subunit (CHRNA4) gene was detected by PCR-RFLP method. A missense mutation (Ser248Phe) in CHRNA4 gene was analyzed by PCR-RFLP using HpaII. A C121W mutation in sodium-channel beta-1 subunit (SCN1B) gene was screened by a PCR-RFLP method using HinPI. A 2-bp deletion in Cystatin B gene was detected by PCR-RFLP using XcmI. The incidence of three FokI polymorphism genotypes in Kuwaiti IGE patients was 1,1 (85%), 1,2 (14%) and 2,2 (1%) respectively. The missense mutation Ser248Phe of CHRNA4 gene was not detected at all in Kuwaiti IGE patients. The C387G transversion resulting in C121W change in third exon of the SCN1B gene was detected in 3/123 patients (2%). The patients carrying this mutation also exhibited febrile seizures. The incidence of 2 bp deletion in the cystatin B gene was found to be 4% (5/123 IGE patients). The data obtained from molecular analysis show a lack of association between three candidate genes and clinical expression of IGE in Kuwaiti Arab children. This is completely different from the findings reported from Caucasian populations of France, Australia and USA in which case a strong association has been reported between IGE and these genes. To whom corresspondence should be addressed. Tel: +965-5319486; Fax: +965-5338940; E-mail: haider@hsc.edu.kw