Chronomodulated rupturable pulsatile drug delivery of theophylline: preparation and in vitro characterization

The aim of the present study was to develop and evaluate chronomodulated rupturable pulsatile drug delivery of theophylline for the treatment of nocturnal asthma. Core tablets containing theophylline were coated with two consecutive layers, an inner swelling layer and an outer rupturable coating layer. The effect of formulation variables such as molecular weight of outer rupturable coating layer, type and amount of swelling layer, weight gain of coating film and influence of paddle speed on drug release were investigated. The drug release from the pulsatile tablets exhibited an initial lag period, followed by a stage of rapid drug release. The optimal level of swelling layer (crospovidone) to achieve a fast and complete release was 20 % w/w. The results indicated that lag time was prolonged with the increased weight gain of coating film. Also no significant difference in the drug release was observed for different rotational speeds. In accordance with the chronomodulated therapy of asthma, the lag time criterion of 5 hours was satisfied by formulation having 11 % weight gain of outer rupturable layer.Colegio de Farmacéuticos de la Provincia de Buenos Aire

The role of color Doppler and spectral flow analysis in the management of pregnancy induced hypertension

Background: Nearly one third intrauterine death of normally formed singleton fetuses are associated with IUGR coexisting with or without pregnancy induced hypertension (PIH). Abnormal fetal circulation is considered a major factor in fetal growth restriction, both as a cause and an indicator. Doppler ultrasound is a relatively new technique which merits investigations as a screening method for IUGR and PIH as both are associated with placental vascular pathology. The development of Doppler ultrasonographic technology, particularly during last 10 years, has provided an opportunity to obtain both qualitative and quantitative assessment of maternal and fetal hemodynamics using a non-invasive method. Objectives were to assess the role of color Doppler and spectral flow analysis in the management of pregnancy induced hypertension.Methods: It was a prospective observational study in which 50 pregnant women were taken as cases with pregnancy induced hypertension and 25 as matched controls without any high-risk factor. All patients were examined for colour Doppler spectral flow analysis. Detailed USG results in the form of maturity by biparietal diameter, head circumference, femoral length, abdominal circumference, liquor, and expected fetal weight were measured and noted. Doppler study of umbilical artery, fetal middle cerebral artery, both maternal uterine arteries and ductus venosus was carried out. Parameters in the form of resistive index (RI), pulsatility index (PI) and systolic/diastolic ratio (S/D) of all four arteries were taken. In ductus venosus waveform, changes in the ‘a’ wave were noted. All participants were followed up from the point of the recruitment up to the time of delivery. At the time of delivery, the mode of delivery, any complications, the Apgar score, weight of the baby, birth asphyxia and admission in NICU were noted.Results: The number of patients with PIH were highest in the age group of 21-25 years [n=31 (62%)]. IUGR of fetus occurred in 74% of the cases with PIH, while no any patients with IUGR fetus among the control group. 92% patients among uterine notches showed abnormal fetal outcome in the form of low birth weight, preterm delivery, LSCS for fetal distress, birth asphyxia or NICU admission of the neonate. Out of total 37 (74%) IUGR cases, 24 (65%) cases had fetoplacental Doppler abnormality. Out of total 6 cases with absent end-diastolic flow (AEDF) 4 cases had abnormal fetal outcome and 2 cases had delivered still-born babies. 20 out of 30 cases had abnormal fetal middle cerebral arterial Doppler (MCA) PI, out of which 19 patients had abnormal fetal outcome. 23 cases had abnormal CPR, out of them 20 (87%) cases had abnormal outcome and only 3 cases had normal fetal outcome. The parameters at the time of delivery are number of cases with delivery before 37 weeks of GA (63.3%), SGA babies (70%), LSCS for fetal distress (43.3%), and NICU admission (43.3%).Conclusions: Examining the maternal vessels using Doppler ultrasound, it is possible to determine the risk of complication developing in the course of pregnancy long before clinical signs of preeclampsia appear, so that therapeutic measures may be undertaken early

Pulsatile drug delivery for the treatment of nocturnal asthma: a chronopharmaceutical approach

The objective of the present study was to develop and evaluate a pulsatile system of theophylline based on chronopharmaceutical considerations. The basic design consists of an impermeable capsule body, which contains the drug and is closed by an erodible tablet plug. The body portion of the hard gelatin capsules was cross-linked by the combined effect of formaldehyde and heat treatment. The formulation variables such as type of plug material, capsule content, different plug composition, plug weight and plug hardness was investigated to characterize the lag time (t10).The results indicated that drug release from the pulsatile capsule exhibited an initial lag period, followed by a stage of rapid drug release. For the complete and rapid drug release from the capsule body, 15% of effervescent agent had to be included in the capsule content. The lag time criterion of 5 hrs was satisfied by the tablet plug containing 16%HPMC K100LV. A good correlation was observed between erodible tablet weight and lag time.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Chronomodulated rupturable pulsatile drug delivery of theophylline: preparation and in vitro characterization

The aim of the present study was to develop and evaluate chronomodulated rupturable pulsatile drug delivery of theophylline for the treatment of nocturnal asthma. Core tablets containing theophylline were coated with two consecutive layers, an inner swelling layer and an outer rupturable coating layer. The effect of formulation variables such as molecular weight of outer rupturable coating layer, type and amount of swelling layer, weight gain of coating film and influence of paddle speed on drug release were investigated. The drug release from the pulsatile tablets exhibited an initial lag period, followed by a stage of rapid drug release. The optimal level of swelling layer (crospovidone) to achieve a fast and complete release was 20 % w/w. The results indicated that lag time was prolonged with the increased weight gain of coating film. Also no significant difference in the drug release was observed for different rotational speeds. In accordance with the chronomodulated therapy of asthma, the lag time criterion of 5 hours was satisfied by formulation having 11 % weight gain of outer rupturable layer.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Educating the world: a remote experiment in photovoltaics

The increasing deployment of photovoltaic (PV) systems requires large numbers of skilled engineers with a greater understanding of all aspects of PV teehnology both theoretical and practical. Developing experimental rigs at universities is expensive and limited to students physically attending the university. One recent approach to increase access to laboratories is the development of remote experiments. Here students can control real experimental equipment using a visual interface via the Internet. In this paper we explore the development of a photovoltaic laboratory to enable users to access and remotely control experimental equipment based at Loughborough University, UK, from anywhere in the world

The development of a remote laboratory for distance learning at Loughborough University

The increasing deployment of photovoltaic systems requires large numbers of skilled engineers with a greater understanding of all aspects of PV technology both theoretical and practical. Developing experimental rigs at universities is expensive and limited to students physically attending the university. One recent approach to increase access to laboratories is the development of remote experiments. Here students can control real experimental equipment using a visual interface via the Internet. In this paper we explore the development of a photovoltaic laboratory to enable users to access and remotely control experimental equipment based at Loughborough University from anywhere in the world

The development of a photovoltaic remotely operated laboratory experiment: a contribution to meeting the challenge of the renewable energy skills shortage

Skills shortages are often quoted as a threat to renewables growth. The increasing deployment of photovoltaic (PV) systems around the world requires large numbers of trained engineers with a greater understanding of all aspects of PV technology both theoretical and practical. The development of experimental rigs at universities and training establishments is expensive and limited to students physically being present for time constrained activities. One recent approach to increase access to laboratories is the development of remote experiments. Here students can control real experimental equipment using a graphical user interface via the Internet. In this paper we explore the development of a PV laboratory that characterises PV panels under different environmental conditions. It enables users to access and remotely control experimental equipment based at Loughborough University, UK, from anywhere in the world via an Internet connection. We report on student experiences using the laboratory from distance

Group B Streptococcus GAPDH Is Released upon Cell Lysis, Associates with Bacterial Surface, and Induces Apoptosis in Murine Macrophages

Glyceraldehyde 3-phosphate dehydrogenases (GAPDH) are cytoplasmic glycolytic enzymes that, despite lacking identifiable secretion signals, have been detected at the surface of several prokaryotic and eukaryotic organisms where they exhibit non-glycolytic functions including adhesion to host components. Group B Streptococcus (GBS) is a human commensal bacterium that has the capacity to cause life-threatening meningitis and septicemia in newborns. Electron microscopy and fluorescence-activated cell sorter (FACS) analysis demonstrated the surface localization of GAPDH in GBS. By addressing the question of GAPDH export to the cell surface of GBS strain NEM316 and isogenic mutant derivatives of our collection, we found that impaired GAPDH presence in the surface and supernatant of GBS was associated with a lower level of bacterial lysis. We also found that following GBS lysis, GAPDH can associate to the surface of many living bacteria. Finally, we provide evidence for a novel function of the secreted GAPDH as an inducer of apoptosis of murine macrophages