Multi-level optimal energy management strategy for a grid tied microgrid considering uncertainty in weather conditions and load

Microgrids require efficient energy management systems to optimize the operation of microgrid sources and achieve economic efficiency. Bi-level energy management model is proposed in this paper to minimize the operational cost of a grid-tied microgrid under load variations and uncertainties in renewable sources while satisfying the various technical constraints. The first level is day ahead scheduling of generation units based on day ahead forecasting of renewable energy sources and load demand. In this paper, a recent meta-heuristic algorithm called Coronavirus Herd Immunity Optimizer (CHIO) is used to solve the problem of day-ahead scheduling of batteries, which is a complex constrained non-linear optimization problem, while the Lagrange multiplier method is used to determine the set-point of the Diesel Generator (DG). The second level of the proposed EMS is rescheduling and updating the set-points of sources in real-time according to the actual solar irradiance, wind speed, load, and grid tariff. In this paper, a novel real-time strategy is proposed to keep the economic operation during real-time under uncertainties. The obtained results show that the CHIO-based bi-level EMS demonstrates an optimal economic operation for a grid-connected microgrid in real-time when there are uncertainties in weather, utility tariffs, and load forecasts.

A comprehensive investigation of Bi2O3 on the physical, structural, optical, and electrical properties of K2O.ZnO.V2O5.B2O3 glasses

The multi-component glass system has a composition of 10K2O-10ZnO-55 B2O3-(25-x)V2O5-xBi2O3 (x = 4, 5, 7.5, 9, 10 mol%) are synthesized by the melt-quenching method. Using X-ray diffraction examination, the amorphous phase in the material was confirmed. The physical characteristics of the produced compositions are examined using density (D) and molar volume (Vm). Calculations of physical properties showed that adding Bi2O3 from 4 to 10 mol% increased the glass density from 2.7878 to 3.3617 g cm-3 and decreased the molar volume from 40.4196 to 38.5895 cm3/mol. Studies of glass samples using the FTIR show bands of absorption for oxides in different structural groups. Octahedral [ BiO 6 ], [ BO 4 ], and tetrahedral [ BO 3 ] structural units are observed in the present glass matrices. The cutoff wavelength ( λ C ), and optical band gap energy were determined using UV absorption spectra. The increase in non-bridging oxygens can be linked to the decrease in optical band gap energy ( E opt ) (direct and indirect) and the increase in cutoff wavelength with an increase in Bi2O3 content. This is attributed to the existence of bismuth ions and the creation of non-bridging oxygens. Besides that, the values of optical parameters, viz., optical electronegativity, refractive index, and molar refractivity, are calculated. The metallization criterion values are less than 1 and the glass samples exhibit an increased tendency towards metallization. Both the conductivity and the dielectric constant increase with the rise in Bi2O3 content, however, the dielectric loss and the impedance reduce. The behavior and values of conductivity for the studied glasses reveal the semiconducting properties of all glass samples. These results suggest that the produced glass samples may be employed as amorphous semiconductors in electronics and memory switching devices.

A comparative study of advanced evolutionary algorithms for optimizing microgrid performance under dynamic pricing conditions

The integration of microgrids into the existing power system framework enhances the reliability and efficiency of the utility grid. This manuscript presents an innovative mathematical paradigm designed for the optimization of both the structural and operational aspects of a grid-connected microgrid, leveraging the principles of Demand-Side Management (DSM). The focus of this work lies in a comprehensive exploration of the implications brought about by the Renewable Generation-Based Dynamic Pricing Demand Response (RGDP-DR) mechanism, particularly in terms of its influence on the optimal microgrid configuration, considering perspectives from end-users and the utility entity. This inquiry is rooted in a holistic assessment that encompasses technical and economic performance benchmarks. The RGDP-induced DR framework adeptly addresses the needs of the consumer base, showcasing notable efficiency and economic feasibility. To address the intricate nonlinear optimization challenge at hand, we employ an evolutionary algorithm named the "Dandelion Algorithm" (DA). A rigorous comparative study is conducted to evaluate the efficacy of four optimization techniques, affirming the supremacy of the proposed DA. Within this discourse, the complexity of microgrid sizing is cast as a dual-objective optimization task. The twin objectives involve minimizing the aggregate annual outlay and reducing emissions. The results of this endeavor unequivocally endorse the superiority of the DA over its counterparts. The DA demonstrates exceptional proficiency in orchestrating the most cost-effective microgrid and consumer invoice, surpassing the performance of alternative optimization methodologies.

The role of diffusion-weighted MRI in the accurate diagnosis of vertebral compression fractures: A comparative study

INTRODUCTION

Accurately distinguishing between benign and malignant vertebral compression fractures is crucial for clinical management. This study evaluated the predictive accuracy of diffusion-weighted imaging (DWI) in differentiating the cause of vertebral fractures using MRI.

METHODS

A longitudinal cross-over study was conducted at Jinnah Postgraduate Medical Centre (JPMC) Karachi from July 2018 to January 2021. Patients with vertebral compression fractures underwent T1-weighted, T2-weighted, and DWI imaging with ADC mapping on a 1.5 T MRI scanner. Imaging findings were compared with histopathologic results and clinical follow-up. Sensitivity, specificity, and ROC curve analyses were performed.

RESULTS

The study enrolled 303 patients with a mean age of 43.6 ± 10.9 years, of whom 118 were male. DWI demonstrated high accuracy in predicting the cause of vertebral compression fractures, with a sensitivity of 96.2 %, a specificity of 76.2 %, and an area under the ROC curve of 0.857. The optimal ADC cut-off value was 0.82 × 10˄-3 mm˄2/s, which yielded a positive predictive value of 79.7 % and a negative predictive value of 95.4 %.

CONCLUSIONS

DWI is a safe and non-invasive imaging modality with excellent predictive accuracy in differentiating between benign and malignant vertebral compression fractures. Iso- or hypointensity of collapsed vertebral bodies on DWI suggests a benign lesion, while T2-weighted hyperintensity is highly indicative of malignancy. Low signal on ADC is also highly indicative of malignant vertebral fractures. Incorporating DWI improves accuracy in assessing vertebral lesions, especially when standard sequences are inconclusive.

IMPLICATIONS FOR PRACTICE

DWI revolutionizes vertebral compression fracture diagnosis, distinguishing between benign and malignant cases. This precision guides treatment decisions, minimizing the necessity for invasive procedures like biopsy. As a safe and reliable imaging method, DWI elevates patient care, ensuring accurate diagnostics and improved outcomes.

A randomized controlled trial comparing the effects of Vitamin E, Ursodeoxycholic acid and Pentoxifylline on Egyptian non-alcoholic steatohepatitis patients

OBJECTIVE

Currently, no NASH-specific therapies are approved by the US Food and Drug Administration. This study aimed to compare the clinical effect of vitamin E (Vit. E), Ursodeoxycholic Acid (UDCA) and pentoxifylline (PTX) on Egyptian patients with NASH with exploration of their possible roles on inflammatory cytokines and chemokines mainly Interleukin 6 (IL6) and Monocyte Chemoattractant Protein-1 (CCL2/MCP-1).

PATIENTS AND METHODS

We conducted a 3-month, randomized, single-blind study in 102 Egyptian NASH patients who were divided into three groups; group 1 received Vit. E 400 mg twice a day, group 2 received UDCA 250 mg twice a day and group 3 received PTX 400 mg twice daily. Liver aminotransferases (AST, ALT), IL6, CCL2/MCP-1, albumin, bilirubin, and lipid panel were measured both before and after intervention intake.

RESULTS

A significant decrease was found in liver aminotransferases, serum cytokine and chemokine in participants after Vit. E, UDCA or PTX intake. Compared to the UDCA and PTX groups, liver aminotransferases, serum cytokine and chemokine showed a more statistically significant reduction after Vit. E administration (50%, 43%, 57% and 55% for ALT, AST, IL6 and CCL2/MCP-1, respectively). In contrast, other biochemical tests showed non-significant change after any drug intake. None of the tested drugs showed significant safety issues in this population.

CONCLUSIONS

Treatment with Vit. E, UDCA and PTX was both safe and effective in improving hepatic aminotransferases and inflammatory markers in Egyptian NASH patients. The superior effect of Vit. E compared to UDCA and PTX may suggest that oxidative stress plays a key role in disease progression of NASH patients. Moreover, IL6 and CCL2/MCP-1 may be used with or without ALT for treatment evaluation of NASH people.

Foliar micromorphology, ultrastructure and histochemical analyses of Tagetes minuta L. leaves

Many Tagetes species are known for producing essential oils and commercially useful bioactive compounds. This study investigated the micromorphological features of the internal and external foliar structures of Tagetes minuta that produce and store these compounds. Stereomicroscopy, light microscopy, scanning electron microscopy, transmission electron microscopy, and histochemical analyses were used to examine T. minuta leaves at three developmental stages. The development of the subdermal secretory cavities revealed that the cells undergo autolysis to form a schizolysigenous cavity in the mature leaves. The ultrastructure of the parenchymal sheath and secretory epithelium within the secretory cavity revealed that plastids change to contain lipid and osmiophilic molecules. The histochemical analyses showed that trichomes on the surface of T. minuta leaves appear to be linear and non-glandular but maintain the ability to store bioactive phytocompounds. These are new findings for T. minuta and provide a better understanding of the exudation process, which can help to optimise essential oil production for industrial applications.

Pharmacokinetic interaction between atorvastatin and fixed-dose combination of sofosbuvir/ledipasvir in healthy male Egyptian volunteers

PURPOSE

Comorbid conditions of heart and liver disorders added to HCV-induced hepatic steatosis make co-administration of statins, and direct-acting antivirals is common in clinical practice. This study aimed to evaluate the pharmacokinetic interaction of atorvastatin and fixed-dose combination of sofosbuvir/ledipasvir "FDCSL" with rationalization to the underlying mechanism.

METHODS

A randomized, three-phase crossover study that involves 12 healthy volunteers was performed. Participants received a single-dose of atorvastatin 80 mg alone, atorvastatin 80-mg plus tablets containing 400/90 mg FDCSL, or tablets containing 400/90 mg FDCSL alone. Plasma samples were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for atorvastatin, sofosbuvir, ledipasvir, and sofosbuvir metabolite "GS-331007," and their pharmacokinetics parameters were determined.

RESULTS

Compared to atorvastatin alone, the administration of FDCSL caused a significant increase in both areas under the concentration-time curve from time zero to infinity (AUC_0-∞) and maximum plasma concentration (C_max) of atorvastatin by 65.5% and 156.0%, respectively. Also, atorvastatin caused a significant increase in the AUC_0-∞ and C_max of sofosbuvir by 32.0% and 11.0%, respectively. Similarly, AUC_0-∞ and C_max of sofosbuvir metabolite significantly increased by 84.0% and 74.0%, respectively. However, ledipasvir AUC_0-∞ showed no significant change after atorvastatin intake. The elimination rate in all drugs revealed no significant changes.

CONCLUSION

After concurrent administration of FDCSL with atorvastatin, the AUC_0-∞ of both atorvastatin and sofosbuvir were increased. Caution should be taken with close monitoring for possible side effects after co-administration of atorvastatin and FDCSL in clinical practice.

Bioactive constituents from Thunbergia erecta as potential anticholinesterase and anti-ageing agents: Experimental and in silico studies

Acetylcholinesterase (AChE) inhibitor and telomerase reverse transcriptase (TERT) potentiator phytochemicals are highly targeted as anti-Alzheimerꞌs disease and as an anti-ageing process. A phytochemical study of Thunbergia erecta aerial parts resulted in the isolation of ten compounds (1-10). Their structures were identified based on spectral data and comparison with literature values. The activity of our pure isolates on AChE and TERT enzymes by documented in vitro assay methods were evaluated. The results indicated that apigenin (2), vanillic acid (4), and acacetin-7-O-β-D-glucoside (7) exhibited potent inhibition of AChE (IC₅₀ 37.33, 30.80 and 49.57 ng/mL, respectively), compared to the standard drug donepezil (IC₅₀ 31.25 ng/mL). In the TERT enzyme assay, compound 7 triggered a 1.66‑fold increase in telomerase activity at the concentration of 2.85 ng/ml. This is the first study that demonstrates that compound 7 isolated from T. erecta can lead to such telomerase activity relative to control cells. Virtual screening studies including docking, rapid overlay chemical structure (ROCS), and calculated structure-property relationships (SPR) were implemented in this work. Molecular docking studies supported the binding of compounds 2, 4, and 7 through hydrogen bonds (HBs) formation to essential amino acid residues namely ARG:24 A, SER:347 A, LYS:51 A, PHE:346 A, and GLY:345 A of acetylcholinesterase. ROCS and SPR analyses realized compound 2 as a possible treatment of Alzheimer's disease and as a lead compound for drug development process through applying semisynthetic modifications.

Double vest lipodermal flaps for depressed facial scars

INTRODUCTION

Depressed tethered scar is a common problem that can cause emotional, social and behavioural problems, especially when it involves the exposed body parts. Several techniques have been described for treating these depressed scars, but none of these can fulfil the optimal results.

AIM

Evaluating the aesthetic outcome of using a double vest lipodermal flaps for treating depressed facial scars.

MATERIALS AND METHODS

The study included 25 patients with depressed facial scars who underwent scar revision. Their mean age was 31 years. Under local anaesthesia, the scarred area was de-epithelialised and double dart lipodermal flaps were used for revision. Visual analogue and Vancouver scar scales were used as subjective and objective parameters of evaluation, respectively.

RESULTS

All the patients followed up for five to eight months. No complications were observed during the scar healing period. Patients satisfaction according to the visual analogue scale showed an average value of 8. The mean total scale according to the Vancouver scar scale was 2.6.

CONCLUSION

The new technique of using double vest lipodermal flaps is simple and offers a promising alternative for revising depressed scars.

Fabrication of a novel low-cost superoleophilic nonanyl chitosan-poly (butyl acrylate) grafted copolymer for the adsorptive removal of crude oil spills

A novel superoleophilic-hydrophobic nonanyl chitosan-poly (butyl acrylate) grafted copolymer was fabricated as a low-cost oil-adsorbent. Chitosan (CS) was coupled with a hydrophobic nonanal (N) to form nonanyl chitosan (NCS) schiff base, and followed by grafting with butyl acrylate monomers (ButA). The grafted copolymer was characterized by FTIR, TGA and SEM tools. The grafting percent was augmented and reached 88.5% with increasing ButA concentration up to 156 mM. Moreover, measurements of contact angle proved the superoleophilic character of NCS-g-poly (ButA) copolymer with an oil-contact angle 31°. Factors affecting the removal process such as contact time, oil type, oil dose, adsorbent dose, temperature and agitation speed were optimized. An increment in the oil removal (%) was observed with increasing the oil viscosity in the order of gasoil < mobil-1 oil < light crude oil < heavy crude oil. Besides, the adsorption process followed the pseudo-second order model and the equilibrium data were sufficiently fitted with the Langmuir model with a maximum adsorption capacity 108.79 g/g at 25 °C. Thermodynamic parameters computed from Van't Hoff plot confirmed the process to be exothermic, favorable and spontaneous. The results nominate the superoleophilic adsorbent as a potential oil- adsorbent for petroleum oil spills removal.

Insights into pathological and molecular characterization of avipoxviruses circulating in Egypt

1. Avipoxvirus (APV) infections are one of many threats inflicting economic losses within the poultry industry, particularly in tropical and subtropical countries. A proper and comprehensive study for APVs is needed to increase the knowledge concerning the diversity and evolution of the virus.2. For this purpose, 136 bird flocks of different species and breeding types were examined for APV infection between October 2016 and November 2017. One hundred and thirty samples had visible pocks on the chorioallantoic membrane (CAM) which were designated as fowl pox-like viruses via amplification of 578 bp from the P4b gene and 1800 bp from the fpv140 locus.4. A comprehensive phylogenetic analysis of fpv167 locus (P4b), fpv140 locus (fpv139 and fpv140) and fpv94 (DNA polymerase) revealed that all the analysed strains belong to fowl pox-like viruses (clade A; subclade A1 and A2). Based on the fpv140 locus full nucleotide sequence, three turkey originated strains were seen to be divergent from chicken originated sequences and branched into novel subclade A1.b.5. Trees comparison, within the term of speculation of virus-host specificity, clearly highlighted a high order specific subgrouping among subclades in the case of the fpv140 locus (including fpv139 and fpv140). Hence, the fowl poxvirus, turkey poxvirus and pigeon poxvirus strains clustered into distinct host-specific subclades A1a, A1.b and A2, respectively, which could not be seen in the FWPV-P4b and DNA polymerase phylogeny.

Extreme tuning of wetting on 1D nanostructures: from a superhydrophilic to a perfect hydrophobic surface

The tuning of wetting over an extreme range, from superhydrophilic to superhydrophobic, was demonstrated on 1D Al/Al₂O₃ nanostructures. While chaotic and tangled 1D Al/Al₂O₃ nanostructures exhibited complete wetting, they became water repellent (with a water contact angle (CA) ≥173°) after the infiltration of poly[bis(2,2,2-trifluoroethoxy)phosphazene] (PTFEP) solution. This simple strategy allows the achievement of two extreme wetting regimes, perfect wetting and non-wetting, without altering the nanostructured surface topography. The same surface was also found to exhibit repellency towards artificial blood and hexadecane.

Effect of subchronic intake of green tea extract on liver of albino rat histomorphometric, ultrastructural and biochemical study

BACKGROUND

There are conflicting reports on the effect of green tea extract (GTE) on the liver of animals. Some studies failed to show any adverse hepatic effects following administration of GTE to mice, rats, and dogs. Others reported severe hepatic necrosis, resulting in death in female Swiss-Webster mice following its administration. The aim of the study was to examine the subchronic toxicity of GTE on the liver of the adult male albino rats.

MATERIALS AND METHODS

Forty male adult Wistar albino rats were used in the study. The rats were divided into four groups; group I (control), group II (low-dose green tea), group III (medium-dose green tea) and group IV (high-dose green tea). Histological, biochemical and histomorphometric analyses were done.

RESULTS

Mild hepatic affections were observed in group II. The affections were severe in groups III and IV. The central veins and hepatic sinusoids were congested. The hepatocytes were degenerated. Hypertrophy of the hepatic arteries, dilation of the bile ducts and cellular infiltration were clearly observed in the last two groups. Mild degenerative changes were observed in the hepatocytes in rat's group II; the cytoplasm was rarefied and vacuolated. Some mitochondria were ruptured. The blood sinusoids were congested. The rough endoplasmic retinaculum was fragmented in group III. More degenerative changes were observed in group IV; the hepatic architectures were lost with disruption of cell membranes. Most of the cell organelles were degenerated and most of mitochondria were ballooned. As compared to that of the control groups: the total serum protein values in groups II, III and IV showed a statistically significant decrease (12%, 20% and 21%, respectively), the mean area per cent of collagen fibres in groups III and IV increased 5 and 7 folds.

CONCLUSIONS

Subchronic administration of GTE resulted in structural and functional affection of the rats' liver. The dose of 250 mg/kg/day seemed to be safe, while the doses of 500 mg/kg/day and 1000 mg/kg/day had deleterious effect being more evident in the latter dose.

Materno-foetal leptin and insulin-like growth factor in low birth weight neonates

Low birth weight (LBW) is a health concern in developing countries. Leptin and insulin-like growth factor-I (IGF-I) are factors that influence LBW. A case-control study was conducted at Medani hospital, Sudan. Cases were women who had LBW deliveries ( 2,500 g) and controls were women with normal-weight babies ( 2.500 – 4,000 g). Sociodemographic and obstetrical characteristics were gathered from both groups and leptin and IGF-I levels were measured by ELISA. Cases and controls (45 in each arm) were matched in their basic data. The median (interquartile) of maternal leptin levels [9.9 (1.9 – 21.8) vs. 16.0 (9.6 – 20.8), ng/ml; P0.001] and IGF-I [1.6 (0.7 – 20.0) vs. 6.1 (4.3 – 7.1) ng/ml ; P 0.001] were significantly lower in cases than in controls. Likewise, cord serum leptin [5.8 (2.1 – 12.6) vs. 20.0 (5.1 – 37.8) ng/ml; P0.001] and cord serum IGF-I [1.7 (1.3 – 2.0) vs. 6.9 (5.9 – 7.4) ng/ml; P0.001] levels were significantly lower in cases than in controls. Significant positive correlation was found between birth weight and cord leptin ( r0.398), maternal ( r0.795) and cord ( r0.863) IGF-I levels. Maternal and cord leptin and IGF-I levels were significantly lower in LBW babies.

The use of multiplex PCR for the diagnosis of viral severe acute respiratory infection in children: a high rate of co-detection during the winter season

Respiratory tract infection is a major cause of hospitalization in children. Although most such infections are viral in origin, it is difficult to differentiate bacterial and viral infections, as the clinical symptoms are similar. Multiplex polymerase chain reaction (PCR) methods allow testing for multiple pathogens simultaneously and are, therefore, gaining interest. This prospective case-control study was conducted from October 2013 to February 2014. Nasopharyngeal (NP) and oropharyngeal (throat) swabs were obtained from children admitted with severe acute respiratory infection (SARI) at a tertiary hospital. A control group of 40 asymptomatic children was included. Testing for 16 viruses was done by real-time multiplex PCR. Multiplex PCR detected a viral pathogen in 159/177 (89.9 %) patients admitted with SARI. There was a high rate of co-infection (46.9 %). Dual detections were observed in 64 (36.2 %), triple detections in 17 (9.6 %), and quadruple detections in 2 (1.1 %) of 177 samples. Seventy-eight patients required intensive care unit (ICU) admission, of whom 28 (35.8 %) had co-infection with multiple viruses. AdV, HBoV, HRV, HEV, and HCoV-OC43 were also detected among asymptomatic children. This study confirms the high rate of detection of viral nucleic acids by multiplex PCR among hospitalized children admitted with SARI, as well as the high rate of co-detection of multiple viruses. AdV, HBoV, HRV, HEV, and HCoV-OC43 were also detected in asymptomatic children, resulting in challenges in clinical interpretation. Studies are required to provide quantitative conclusions that will facilitate clinical interpretation and application of the results in the clinical setting.

FOLFOX as Perioperative Chemotherapy of localized Gastric Cancer: Efficacy and Tolerance

BACKGROUND

Use of perioperative chemotherapy had significantly improved prognosis of localized gastric cancer. Two studies have validated this approach using cisplatin based chemotherapy despite important toxicities. We conducted this study with the aim to evaluate efficacy and toxicity of FOLFOX regimen in this setting.

MATERIAL AND METHODS

This is a retrospective study including patients followed for gastric cancer in the Oncology Department of the military hospital Mohamed V in Rabat, Morocco over a period of 7 years from 2007 to 2013. Patients received 4 cycles of mFOLFOX as perioperative regimen. Assessment of tumor response after completion of preoperative chemotherapy was granted by comparative CT scan, tumor markers measurements and R0 surgery rate.Adverse events were graded according to classification of the National Cancer Institute Common Toxicity Criteria version 4.0.

RESULTS

Thirty-one patients were included in this study. Use of preoperative chemotherapy showed partial response in fourteen patients (45.1%), stabilization in fifteen patients (48.4%). Tumor markers CEA and CA 19- 9 were significantly decreased. R0 resection rate was 83.87%. Only 2 (6.45%) cases of grade 3/4 hematologic toxicity were reported in our study. Achieving programmed postoperative chemotherapy was possible in 72.41% of patients.

CONCLUSIONS

Our study is limited by the retrospective design and small sample size but FOLFOX chemotherapy seems effective and well tolerated in this setting and its place deserves to be studied in a larger study.

Field evaluation of a PfHRP-2/pLDH rapid diagnostic test and light microscopy for diagnosis and screening of falciparum malaria during the peak seasonal transmission in an endemic area in Yemen

BACKGROUND

Malaria is a public health threat in Yemen, with 149,451 cases being reported in 2013. Of these, Plasmodium falciparum represents 99%. Prompt diagnosis by light microscopy (LM) and rapid diagnostic tests (RTDs) is a key element in the national strategy of malaria control. The heterogeneous epidemiology of malaria in the country necessitates the field evaluation of the current diagnostic strategies, especially RDTs. Thus, the present study aimed to evaluate LM and an RDT, combining both P. falciparum histidine-rich protein-2 (PfHRP-2) and Plasmodium lactate dehydrogenase (pLDH), for falciparum malaria diagnosis and survey in a malaria-endemic area during the transmission season against nested polymerase chain reaction (PCR) as the reference method.

METHODS

A household-based, cross-sectional malaria survey was conducted in Mawza District, a malaria-endemic area in Taiz governorate. A total of 488 participants were screened using LM and PfHRP-2/pLDH RDT. Positive samples (160) and randomly selected negative samples (52) by both RDT and LM were further analysed using 18S rRNA-based nested PCR.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the RDT were 96.0% (95% confidence interval (CI): 90.9-98.3), 56.0% (95% CI: 44.7-66.8), 76.3% (95% CI: 69.0-82.3), and 90.4% (95% CI: 78.8-96.8), respectively. On the other hand, LM showed sensitivity of 37.6% (95% CI: 29.6-46.3), specificity of 97.6% (95% CI: 91.7-99.7), PPV of 95.9% (95% CI: 86.3-98.9), and NPV of 51.3% (95% CI: 43.2-59.2). The sensitivity of LM dropped to 8.5% for detecting asymptomatic malaria. Malaria prevalence was 32.8% (32.1 and 37.5% for ≥10 and <10 years, respectively) with the RDT compared with 10.7% (10.8 and 9.4% for age groups of ≥10 and <10 years, respectively) with LM. Among asymptomatic malaria individuals, LM and RDT-based prevalence rates were 1.6 and 25.6%, respectively. However, rates of 88.2 and 94.1% of infection with P. falciparum were found among patients who reported fever in the 48 h prior to the survey by LM and PfHRP-2/pLDH RDT, respectively.

CONCLUSIONS

The PfHRP-2/pLDH RDT shows high sensitivity for the survey of falciparum malaria even for asymptomatic malaria cases. Although the RDT had high sensitivity, its high false-positivity rate limits its utility as a single diagnostic tool for clinical diagnosis of malaria. On the other hand, low sensitivity of LM indicates that a high proportion of malaria cases is missed, underestimating the true prevalence of malaria in the community. Higher NPV of PfHRP-2/pLDH RDT than LM can give a straightforward exclusion of malaria among febrile patients, helping to avoid unnecessary presumptive treatments.

Seasonal variation and hypertensive disorders of pregnancy in eastern Sudan

The aim of this study was to investigate the seasonal variation and hypertensive disorders of pregnancy in eastern Sudan, in the period between January 2008 and December 2010. The medical files of women attending at Kassala hospital, eastern Sudan with hypertension, with or without proteinuria were retrospectively retrieved. The data of patients with hypertensive disorders of pregnancy were compared with a similar number of controls that were normotensive and non-proteinuric. During the study period, there were 9,578 deliveries; 153 patients had hypertensive disorders of pregnancy, yielding an incidence rate of 1.6%. Of all cases and controls (306), there were 183 (59.8%) deliveries in winter, 84 (27.5%) in summer and 39 (12.7%) in autumn. The highest rate of pre-eclampsia was in winter (1.1%) (CI = 1.1-2.7, OR = 1.7, p = 0.004) and the lowest rate was in autumn (0.2%) (CI = 0.4-1.8, OR = 0.8, p = 0.758.). Our study revealed significant association between the incidence of hypertensive disorders of pregnancy and the winter season (103 (67.3%) vs 80 (52.3%), p = 0.001). Thus, more attention in the winter season might reduce the morbidity and mortality of hypertensive disorders of pregnancy.

Bond durability of self-etch adhesive to ethanol-based chlorhexidine pretreated dentin after storage in artificial saliva and under intrapulpal pressure simulation

OBJECTIVE

To evaluate the bond strength durability of a single-step self-etch adhesive to dentin pretreated with either ethanol-based chlorhexidine (ECHX) or water-based chlorhexidine (WCHX) after storage in artificial saliva and under intrapulpal pressure simulation (IPPS).

METHODS

The occlusal enamel of 30 freshly extracted premolars was trimmed to expose midcoronal dentin. Roots were sectioned to expose the pulp chamber. Specimens were distributed over three groups (n=10) according to the dentin pretreatment used. In the first group, Adper Easy One (3M ESPE) was applied to the dentin surfaces according to the manufacturer's instructions (control group). In the second group, dentin was pretreated before bonding with 1 mL of 2% CHX diacetate dissolved in 100% ethanol (ECHX). The third group received the same pretreatment; however, CHX was dissolved in distilled water (WCHX). Pretreatment and bonding were carried out while the specimens were subjected to IPPS. Resin composite (Valux Plus, 3MESPE) buildups were made. After curing, specimens were stored in artificial saliva and under IPPS at 37°C in a specially constructed incubator (n=5/group) either for 24 hours or six months prior to testing. Thereafter, bonded specimens were sectioned into sticks with a cross section of 0.9 ± 0.01 mm(2) and subjected to microtensile bond strength (μTBS) testing (n=25/subgroup) using a universal testing machine. Data were statistically analyzed using two-way analysis of variance (ANOVA) with repeated measures, one-way ANOVA , and Bonferroni post hoc tests (p≤0.05). Failure modes were determined using a scanning electron microscope.

RESULTS

After 24 hours of storage, control and WCHX groups revealed significantly higher μTBS than the ECHX group. After six-month storage in artificial saliva and IPPS, only the WCHX group maintained its μTBS value. The predominant mode of failure was the mixed type, except for the ECHX group, which was mostly adhesive.

CONCLUSION

Pretreatment of the dentin with ECHX had a negative effect on bonding of the tested single-step self-etch adhesive; however, WCHX showed bond stability under IPPS.

Problems leading to conversion in laparoscopic cholecystectomy

In prospective study, the various reasons for conversion in laparoscopic cholecystectomy were shown and recommended various measures to decrease the incidence of conversion and associated complications with this procedure. Fifty cases of conversion in laparoscopic cholecystectomy were studied in Dhaka Medical College Hospital & Bangabandhu Sheikh Mujib Medical University from July 2002 to July 2004. The commonest cause of conversion was dense pericholecystic adhesion or unclear anatomy (24%). Next common cause was accidental injury to surrounding structures (18%) and uncontrolled bleeding (14%) and thick fibrosed gall bladder (14%). Other causes were gall bladder wall perforation (6%), carcinoma gall bladder (6%) and choledocholithiasis (6%), anatomic variation (4%), equipment failure (4%), cholecystoduodenal fistula (2%) and choledochal cyst (2%). Proper case selection, good laparoscopic skill and adequate experience of the surgeon are the prerequisites for safe laparoscopic cholecystectomy and thereby reducing conversion rate.

Association of positive thyroid auto antibodies with thyroid carcinoma

The association between thyroid autoimmunity and thyroid cancer was carried out in a series of solitary thyroid nodules submitted to fine-needle aspiration cytology and subsequent histopathology. US guided FNACs were obtained from 295 unselected consecutive patients with single thyroid nodules and positive (98) or negative (197) serum anti-thyroid antibody. Cytological results were classified in three classes of increased risk of malignancy: low risk (class II); indeterminate risk (class III); and suspect or malignant (class IV). A higher prevalence of class III (29.6%, p<0.05) and class IV (17.34%, p<0.05) and lower prevalence of class II (52.06%, p<0.01) were found in ATA+ nodules respectively. By multivariate logistic regression analysis ATA+ conferred a significant risk (odds ratio: 1.97 & 95% confidence interval: 0.97-3.97) for class IV cytology independently for age and sex. In 53 patients where thyroidectomy was carried out, thyroid cancer was found in (86.66%) patients with class IV nodules, in (19.4%) of class III nodules (all ATA-) and in none of 7 class II nodules. Histologically proven thyroid cancer (mostly papillary) was then observed in a higher proportion (13.2%) of ATA+, when compared with ATA- nodules (8.1%, p>0.01), but the significance of this finding is limited by the low number of class II nodules operated on. The presence of ATA+ confers an increased risk of suspicious or malignant cytology in solitary thyroid nodules.

High incidence of obstetric complications in Kassala Hospital, Eastern Sudan

Medical files of women delivered at Kassala Hospital, Eastern Sudan in the period of January-December 2009 were reviewed retrospectively. Out of 4,689 delivered women, 14.7% were teenagers, 67.1% had no antenatal care and 12.6% were grandmultiparous. Obstetric complications included: pre-term birth (2.6%); pre-eclampsia/eclampsia (4.2%); haemorrhage (2.9%); malpresentation (5.5%); obstructed labour (1.9%) and ruptured uterus (0.6%). Caesarean delivery rate was 31.1%. While 89.4% of the newborn babies were taken home, 6% were admitted to the nursery, 4.4% were stillbirths, and 0.2% immediate neonatal deaths. There were 26 maternal deaths (550 per 100,000 live births), mainly due to septicaemia (38.4%), haemorrhage (19.2%), embolism (15.3%) and malaria (11.5%). Thus, there is a high frequency of maternal morbidities and mortality which needs improvement in obstetric care. It is important to make visits from a tertiary hospital to the region to collect statistics and discuss management of the problems they reveal, with the local staff.

Acute abdomen 10 years after surgery for duodenal ulcer disease

A 55 years old male was admitted in the surgical unit of Dhaka Medical College & Hospital with the complaints of pain and discomfort in the upper abdomen for 1 day and hiccough and vomiting for several episodes for same duration. He had history of abdominal operation 10 years back for his peptic ulcer disease probably due to pyloric stenosis. On examination a linear scar mark was present along the upper midline region & visible peristalsis was seen on the left hypochondriac region. A palpable diffuse lump was present in the left hypochondriac region which was intraperitoneal seemed to be distended gut and the peristaltic wave moved from left to right. Endoscopy of upper GIT Showed loops of small intestine (evidenced by valvulae conneventes) protruded through a stoma suggestive of jejunogastric intussusception. Laparotomy revealed a portion of adherent small gut already become gangrenous so the whole portion of the intussuscepted gut was resected. After that revision and take-down of the anastomosis was done with vicryl stitches. The post operative period was uneventful. The patient underwent regular follow up.

Hearts from DCD donors display acceptable biventricular function after heart transplantation in pigs

Cardiac transplantation is in decline, in contrast to other solid organs where the number of solid organ transplants from donors after circulatory death (DCD) is increasing. Hearts from DCD donors are not currently utilized due to concerns that they may suffer irreversible cardiac injury with resultant poor graft function. Using a large animal model, we tested the hypothesis that hearts from DCD donors would be suitable for transplantation. Donor pigs were subjected to hypoxic cardiac arrest (DCD) followed by 15 min of warm ischemia and resuscitation on cardiopulmonary bypass, or brainstem death (BSD) via intracerebral balloon inflation. Cardiac function was assessed through load-independent measures and magnetic resonance imaging and spectroscopy. After resuscitation, DCD hearts had near normal contractility, although stroke volume was reduced, comparable to BSD hearts. DCD hearts had a significant decline in phosphocreatine and increase in inorganic phosphate during the hypoxic period, with a return to baseline levels after reperfusion. After transplantation, cardiac function was comparable between BSD and DCD groups. Therefore, in a large animal model, the DCD heart maintains viability and recovers function similar to that of the BSD heart and may be suitable for clinical transplantation. Further study is warranted on optimal reperfusion strategies.

Polymorphisms of the SLC11A1 gene and resistance to bovine tuberculosis in African Zebu cattle

Bovine tuberculosis (BTB) is a considerable health threat to livestock keepers and general communities in many developing countries. Information on genetic resistance or susceptibility because of polymorphisms of candidate genes could be used in making selection decisions for breeding disease tolerant/resistant animals. Here, we investigated associations between polymorphisms at the solute carrier family 11 (proton-coupled divalent metal ion transporters), member 1 gene (SLC11A1, previously known as natural resistant associated macrophage protein 1, NRAMP1), with BTB phenotypes in Chadian cattle. Phenotypes were (i) single intradermal comparative cervical tuberculin test (SICCT) outcome, (ii) presence of gross visible lung lesions, (iii) a bacteriological culture test outcome and (iv) a predicted true BTB infection status using a Bayesian model. All traits were recorded as binary (presence or absence) traits. A total of 211 cattle were genotyped for a microsatellite within the SLC11A1 candidate gene. Standard linear and threshold-liability models regressing BTB traits on copy number of SLC11A1 alleles revealed statistically significant effects of SLC11A1 alleles (P < 0.001) on most BTB traits. Polymorphisms (alleles 211, 215 and 217) are significantly related to lower incidence of BTB traits in Chadian cattle. This is the first study to report the association of SLC11A1 gene polymorphisms with BTB traits in Chadian or any other African cattle breeds.

Synthesis and spectral characterization of CoxMg1-xAl2O4 as new nano-coloring agent of ceramic pigment

New nano-blue ceramic pigments of Co(x)Mg(1-x)Al(2)O(4) (0< or =x< or =0.1) have been prepared by co-precipitate-combustion as a hybrid method using urea as a fuel at 500 degrees C in open furnace in air atmosphere. The structure of pigment is assigned based on TGA/DTA/DrTGA analyses, X-ray diffraction (XRD) and transmission electron microscopy (TEM). Also, electronic spectra, infrared (IR) and diffuse reflectance spectroscopy (DRS) using CIE L*a*b* parameter measurement techniques were used. The results revealed that the nano-particle size of pigments were obtained in the range 30-38 nm as well as the varying colors and particle size as a result of different calcinations temperatures within the range of 500-1200 degrees C for 2h.

Prevalence and etiology of nosocomial diarrhoea in children < 5 years in Tikrit teaching hospital

A cross-sectional hospital-based study was carried out at Tikrit teaching hospital, Iraq, from October 2004 to September 2005, to identify the prevalence and etiology of nosocomial infectious diarrhoea among children under 5 years of age. Of 259 children admitted to the paediatric ward for reasons other than diarrhoea and hospitalized for more than 3 days, clinical and laboratory analysis of stool samples showed nosocomial diarrhoea in 84 children (32.4%). The most common causative agents were enteropathogenic Escherichia coli (25.9%), Clostridium difficile (21.0%) and rotavirus (18.5%). Single infectious agents caused 63.1% of the cases, while mixed infections were detected in 16.7%; in 20.2% of children the cause remained unknown.

Patient with bilateral breast enlargement and hypospadias

A 20 year old man was admitted in the surgical unit of Dhaka Medical College Hospital on August 2007 presented with Hypospadias & underdeveloped penis from childhood, gradual enlargement of both breasts for the last 10 years, absence of axillary and pubic hair from puberty & painful swelling of both testes for the last 3 years. The patient was regarded as a female upto the age of 10 years. He has got no voice change since puberty. On examination he had average body built, there was bilateral gynaecomastia, hypospadias, rudimentary penis & absence of pubic and axillary hair. His testosterone level, serum prolactin level, serum progesterone level, serum estradiol level was done. Cytology on buccal smear done and ultrasonography revealed no ovary and uterus. Ultimately patient was diagnosed as a case of androgen insensitivity syndrome (AIS). The case is reported for clinical awareness & to share our experience.

Synthesis and characterization of new nano-particles as blue ceramic pigment

The synthesis of a new nano-blue ceramic pigment CoxMg1-xAl2O4 (0 < or = x < or = 0.1) using the combination between co-precipitation and combustion synthesis (CS) method. The structure of pigments is assigned based on thermogravimetric and differential thermogravimetric analysis (TG-DTGA), X-ray diffractions (XRD), and UV-vis spectroscopy. Also, diffuse reflectance spectroscopy (DRS) using CIE L*a*b* parameter measurement method, infrared spectroscopy (IR) and transmission electron microscopy (TEM) is used. The result revealed that the nano-size particle pigment was obtained in range 24-35 nm by using 3-methyl-pyrozole-5-one (3MP5O) as a fuel at 400 degrees C in open furnace. Also, results show the varying colors and particles' size as a result of different calcination temperatures from 500 to 1200 degrees C for 2h.

A comparative assessment of heavy metal accumulation in soft parts and byssus of mussels from subarctic, temperate, subtropical and tropical marine environments

Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the same protocols, analytical methodologies and analysts. Factor analysis demonstrated that mussels inhabiting extremely contaminated areas (e.g. from Japanese and Swedish metallurgy sources) could be separated from mussels from other contaminated areas, and that metals such as Cd, Pb, Cu and Zn could be used to identify heavily contaminated samples while Co, Fe, Cr and Ni concentrations were good markers for exposure to inputs from different industrial sources. Furthermore byssus, like soft tissue, selectively and sensitively reflects variations of certain metal concentrations in ambient waters and thus serves as a reliable biomonitor for these contaminants in a variety of coastal and estuarine areas.

Chronic elevation of parathyroid hormone in mice reduces expression of sclerostin by osteocytes: a novel mechanism for hormonal control of osteoblastogenesis

Both chronic excess of PTH, as in hyperparathyroidism, and intermittent elevation of PTH (by daily injections) increase the number of osteoblasts; albeit, the former is associated with bone catabolism and the later with bone anabolism. Intermittent PTH increases osteoblast number by attenuating osteoblast apoptosis, an effect that requires the transcription factor Runx2. However, chronic elevation of PTH does not affect osteoblast apoptosis because it stimulates the proteasomal degradation of Runx2. Here, we studied the effects of PTH on Sost, a Runx2 target gene expressed in osteocytes (former osteoblasts embedded in the bone matrix), which antagonizes the pro-osteoblastogenic actions of bone morphogenetic proteins and Wnts. We report that continuous infusion of PTH to mice for 4 d decreased Sost mRNA expression in vertebral bone by 80-90%. This effect was accompanied by a comparable reduction of sclerostin, the product of Sost, in osteocytes, as determined by quantitative immunoblot analysis of bone extracts and by immunostaining. In contrast, a single injection of PTH caused a transient 50% reduction in Sost mRNA at 2 h, but four daily injections had no effect on Sost mRNA or sclerostin. PTH strongly decreased Sost expression in osteocytes formed in primary cultures of neonatal murine calvaria cells as well as in osteocytic MLO-A5 cells, demonstrating a direct effect of PTH on this cell type. These results, together with evidence that sclerostin antagonizes bone morphogenetic proteins and Wnts, strongly suggest that suppression of Sost by PTH represents a novel mechanism for hormonal control of osteoblastogenesis mediated by osteocytes.

Tumour T-lymphocyte subset infiltration and tumour recurrence following curative resection for colorectal cancer

AIM

The relationship of tumour T-lymphocytic subset infiltration and recurrence in patients undergoing potentially curative resection for colorectal cancer has not been clearly defined.

METHODS

Tumour sections from patients who had undergone potentially curative resection for colorectal cancer were stained and counted for CD4+ and CD8+ T-lymphocytes.

RESULTS

Twenty-three patients developed recurrence during the follow-up period. Patients were grouped according to whether or not they developed recurrence. The groups were similar in age, sex, site of tumour, Dukes stage and the numbers of patients receiving adjuvant therapy. The total percentage volume of labelled CD4+ T-lymphocytes in the tumour was significantly lower in the patients who recurred (p<0.05).

CONCLUSIONS

The results of the present pilot study suggest that a reduction in tumour T-lymphocyte infiltration, in particular CD4+ T-lymphocyte infiltration, is associated with recurrence in patients following potentially curative resection for colorectal cancer.

Endometrial cancer metastasis presenting as a grossly swollen toe

Metastasis to the peripheral skeleton, especially in the face of low stage disease, is rare. This report describes the case of a 77-year-old lady with stage IC disease who underwent curative total abdominal hysterectomy and bilateral salpingo-oopherectomy 2 years prior to presenting with a painless gigantism of her fourth toe. A histologic diagnosis of dedifferentiated endometrial metastasis with sarcomatous differentiation was made following amputation of the toe. Osseous metastasis to bone is discussed in the context of endometrial carcinoma and the literature reviewed. This paper reports the first case of endometrial carcinoma metastasis presenting as gross swelling of a toe.

Antioxidant requirements for bovine oocytes varies during in vitro maturation, fertilization and development

Antioxidants may be beneficial additives to synthetic culture media because these well defined media lack serum or other macromolecules that serve as reactive oxygen species scavengers. In this study, three separate experiments were performed to determine the effects of antioxidants on the development of oocytes to the morula and blastocyst stage when added during in vitro maturation (IVM) of bovine oocytes, during in vitro fertilization (IVF), and during embryo culture for the first 72 h of the development period. Bovine oocytes were matured, fertilized (under 20% O(2)), and embryos were cultured (under 7% O(2)) in defined conditioned medium in vitro with or without supplementation with the antioxidant cysteine, N-acetyl-L-cysteine (NAC), catalase and superoxide dismutase (SOD). Significant improvements in the proportion of oocytes undergoing morula and blastocyst development (33.3% versus 20.3%, P<0.05) were achieved when cysteine (0.6 mM) was added to the maturation medium as compared to control medium without antioxidant supplementation. However, the addition of NAC (0.6mM), catalase (5 or 127 U/ml) or SOD (10 or 1000 U/ml) to the maturation medium did not improve the proportion of oocytes undergoing morula and blastocyst development. During the IVF period, addition of antioxidants (cysteine or NAC 0.6mM, catalase 127U/ml, SOD 100U/ml) significantly reduced the subsequent rate of bovine embryo development to the morula and blastocyst stage (P<0.05). In a defined medium for embryo culture (7% O(2)), the addition of cysteine improved the development of bovine embryos while NAC, catalase and SOD had no positive effect on embryonic development. Our study showed that medium supplementation with cysteine during IVM and in vitro culture (IVC) improved the rate of bovine embryo development, in contrast to extracellular antioxidants like catalase and SOD that caused no improvement.

Invasive pulmonary aspergillosis complicating chronic obstructive pulmonary disease in an immunocompetent patient

Immunocompromised individuals are susceptible to pulmonary aspergillus infection, but invasive aspergillus infection is extremely rare in the presence of normal immunity. We report a case of invasive aspergillosis in an immunocompetent 63-year-old male with chronic obstructive pulmonary disease (COPD). Patients with COPD may be at risk for developing pulmonary aspergillus infection, which should be considered as a diagnostic possibility in patients with unresolving pulmonary infection.

Reversal of bone loss in mice by nongenotropic signaling of sex steroids

We show that sex steroids protect the adult murine skeleton through a mechanism that is distinct from that used to preserve the mass and function of reproductive organs. The classical genotropic actions of sex steroid receptors are dispensable for their bone protective effects, but essential for their effects on reproductive tissues. A synthetic ligand (4-estren-3alpha,17beta-diol) that reproduces the nongenotropic effects of sex steroids, without affecting classical transcription, increases bone mass and strength in ovariectomized females above the level of the estrogen-replete state and is at least as effective as dihydrotestosterone in orchidectomized males, without affecting reproductive organs. Such ligands merit investigation as potential therapeutic alternatives to hormone replacement for osteoporosis in both women and men [corrected].

Differential expression of members of the tumor necrosis factor alpha-related apoptosis-inducing ligand pathway in prostate cancer cells

Androgen ablation therapy induces apoptosis only in androgen-sensitive prostate cancer cells; therefore, other cytotoxic drugs are being used to induce apoptosis in androgen-refractory cells. Mifepristone, an antiprogestin used individually or together with the antiestrogen Tamoxifen, has been recommended for induction of cell death and treatment of several hormonal cancers. However, little is known about the mechanism of action of these drugs in prostate cancer. Therefore, we investigated the effect of Mifepristone on the tumor necrosis factor alpha-related apoptosis-inducing ligand (TRAIL) pathway, a newly identified and very effective member of tumor necrosis factor-alpha family. Mifepristone and Tamoxifen induced significant expression of death receptors in prostate cancer cells in vitro and in xenografts. However, Mifepristone in combination with Tamoxifen did not increase prostate cancer cell death compared with their individual values. The involvement of the TRAIL pathway was further confirmed by the activation of caspase-8 in Mifepristone-treated cells. This was followed by truncation of Bid, confirming that Mifepristone activates the TRAIL pathway. This knowledge is being used to design a combination treatment of TRAIL and Mifepristone to induce significant apoptosis in prostate cancer cells.

Attenuation of the self-renewal of transit-amplifying osteoblast progenitors in the murine bone marrow by 17 beta-estradiol

In agreement with evidence that estrogens slow the rate of bone remodeling by suppressing the production of both osteoclasts and osteoblasts, loss of estrogens leads to an increase in the number of osteoclast as well as early osteoblast progenitors (CFU-osteoblasts; CFU-OBs) in the murine bone marrow. Here we show that CFU-OBs are early transit-amplifying progenitors, i.e., dividing cells capable of limited self-renewal, and that 17 beta-estradiol acts in vivo and in vitro to attenuate their self-renewal by approximately 50%. Consistent with a direct receptor-mediated action of estrogens on early mesenchymal cell progenitors, anti-estrogen receptor-alpha (anti-ER alpha) Ab's stain a small number of marrow cells that exhibit characteristics of primitive undifferentiated cells, including a high nucleus/cytoplasm ratio and lack of lineage-specific biochemical markers; the effect of 17 beta-estradiol on CFU-OB self-renewal is absent in mice lacking ER alpha. Because both osteoblasts and the stromal/osteoblastic cells that are required for osteoclast development are derived from CFU-OBs, suppression of the self-renewal of this common progenitor may represent a key mechanism of the anti-remodeling effects of estrogens.

Co-oximetry interference by hemoglobin-based blood substitutes

The blood substitutes now being developed from molecularly modified hemoglobin interfere with a wide variety of clinical analyzers, but their effects on cooximeters are unknown. Therefore, we investigated the effects of five hemoglobin-based blood substitutes on the measurements of eight different oximeters and cooximeters: the AVL Omni 6, the AVOXimeters 1000 and 4000, the Ciba Corning (now Bayer) CC270 CO-Oximeter, the Instrumentation Laboratory Synthesis 35, the IL482 and IL682 CO-Oximeters, and the Radiometer OSM3 Hemoximeter. The five blood substitutes in this study were obtained from Apex Bioscience (Research Triangle Park, NC), Baxter Healthcare Corp. (Deerfield, IL), Biopure Corp. (Cambridge, MA), Hemoglobin Therapeutics, and Hemosol, Inc. (Etobicoke, Ontario, Canada). A cooximeter control was used to compare the eight different instruments' measurements on unaltered human hemoglobin. The instruments yielded measurements of total hemoglobin concentration in undiluted blood substitutes that were generally not more variable than those on the control material. By contrast, when compared with readings on controls, the test instruments yielded measurements of the fractional concentrations of oxy-, deoxy-, carboxy-, and methemoglobin that showed greater instrument-to-instrument disparities and larger standard deviations about the all-instrument means. In some cases, the interference was even more obvious: five of six cooximeters gave negative carboxyhemoglobin readings on one particular product. Our findings indicate that the instruments will give less accurate but clinically useful measurements in the presence of these hemoglobin-based blood substitutes.

IMPLICATIONS

We investigated the effects of five hemoglobin-based blood substitutes on the measurements of eight different cooximeters. Some blood substitutes caused obvious interference, such as negative carboxyhemoglobin readings; however, the findings indicate that cooximeters will generally give less accurate but clinically useful measurements in the presence of the hemoglobin-based blood substitutes that were tested.

Sorption kinetics of lead ions by zeolite tuff

The kinetics of sorption of Pb ions by zeolite tuff treated with NaCl solution was studied using agitated batch laboratory apparatus. The uptake of ions was determined as a function of time at different values of initial Pb ion concentration, zeolite particle size, slurry concentration, solution temperature and pH. The pseudo-second order reaction model was successfully applied to the experimental data with correlation coefficients higher than 0.98. Sorption rates decreased with increase in average particle diameter while it increased with increase in each of the initial Pb ion concentration, slurry concentration, solution temperature and solution pH. Results indicate the importance of chemisorption.

Report of a medical mission to Somaliland, 2001

Somaliland is a self-declared state, not recognized by the nations of the world. Sixty percent of the population are herders or small scale farmers. Gross national product and other data are not available, but it is evident, according to surveys conducted by the United Nations, that most of the population has a low income. The health-care system consists of a public sector, which covers primary care, hospital care, immunizations, and tuberculosis care. The major clinical problems are tuberculosis, malaria and childhood diarrhea. Lack of trained personnel is a major difficulty in the health care system. This paper describes visits to health care facilities in Somaliland, and suggests some improvements for the system.

Use of palm mid-fraction in dark chocolate as base filling centre at different storage temperatures

Dark chocolates filled with palm mid-fraction (PMF) were stored at different temperatures to evaluate the physical and chemical changes. Storage at low temperature (18 degrees C) reduces the PMF migration to negligible extent. Higher storage temperatures (30 and 35 degrees C) increased the PMF migration from the filling centre into the chocolate coating. As a consequence of fat migration, fatty acid composition, triglyceride composition, hardness, solid fat content, melting point and polymorphic structure changed, leading to bloom formation, which started by fat migration and was influenced by recrystallization tendency within the chocolate coating.

The heliangolide dihydrohirsutolide from Arctotis fastuosa and dichloromethyldihydrohirsutolide

Three of ten sesquiterpene lactones isolated from the herb of Arctotis fastuosa (Asteraceae) belong to the heliangolide series. The first was identified as hirsutolide, the second is new and named dihydrohirsutolide, and the third, dichloromethyldihydrohirsutolide, is an artifact. The known degraded carotenoid loliolide was also isolated. Structures were established by spectroscopic methods including IR, 1D-/2D-1H-NMR, 13C-NMR, GHSQC, GHMBC, HREIMS and CD.

H-reflex changes under spinal loading and unloading conditions in normal subjects

OBJECTIVE

The soleus H- reflex is usually tested clinically in patients lying prone, with the H-latency always the criterion of choice for detecting abnormality. However, stresses on the spine vary during lying, standing, loading (weight lifting) and unloading. So the objective of this study was to measure changes in the H-reflex under 4 different loading conditions and to investigate whether mechanical loading of the spine would affect the H-reflex parameters.

METHODS

Twenty healthy volunteers (22-46 years) with no history of significant low back pain or radiculopathy participated in the study. A Cadwell Excel electromyography unit was used to elicit and record the soleus H-reflex. The tibial nerve was stimulated at the popliteal fossa using 1 ms pulses at 0.2 pps of H-max. Each subject was tested under 4 different conditions: prone lying, free standing, standing while lifting 20% of his or her body weight, and standing while unloaded by 25% of his/or her body weight by a ZUNI II unloading system. For each subject, the peak-to-peak amplitudes of the maximum obtained H- reflex and the onset latencies of 8 separate traces were averaged for both lower extremities. Two-factor, repeated-measures ANOVAs were used to test the effect of the condition and side on the H-reflex amplitude and latency with ( approximately =0.025).

RESULTS

The H-reflex was inhibited during standing, loading and unloading as compared with prone lying. The H-reflex was recovered during loading as compared with during standing. There were no significant changes in the H-reflex latency under the 4 different conditions. Both lower extremities showed similar pattern of changes in the H-reflexes.

CONCLUSIONS

These results imply a significant interplay between peripheral and central mechanisms and their effects on the spinal motoneurons. This in turn suggests that testing of the H-reflex amplitude and latency under functional conditions, such as standing may be useful in detecting subtle changes in root impingement.

Dual renal transplant from a non-heart beating donor

In September 1998, a 48 year old male underwent bilateral renal transplantation from a 51 year old non-heart beating donor (NHBD) with ischemic heart disease. The grafts exhibited delayed graft function, otherwise short term results have been good, with a three month serum creatinine of 80 mumol/l, three month GFR of 79 ml/min per 1.73 m2 BSA, and no episodes of acute rejection. We advocate dual transplantation when sub-optimal NHBD kidneys are otherwise in danger of being discarded.