Investigation of structural, optical and electrical conductivity of a new organic inorganic bromide: [C12H17N2]2ZnBr4

A new organic-inorganic hybrid, namely the [C₁₂H₁₇N₂]₂ZnBr₄ compound, has been synthesized and studied by single-crystal X-ray diffraction and optical and complex impedance spectroscopy. It crystallized in the centrosymmetric P2₁/n space group at room temperature. The asymmetric unit is constituted by [ZnBr₄]^2- anions, showing slightly distorted tetrahedral geometry, surrounded by four organic (C₁₂H₁₇N₂)⁺ cations. The crystal packing is stabilized by N-H⋯Br and C-H⋯Br hydrogen bonds arranged in a three-dimensional network. The optical absorption measurement confirms the semiconductor nature with a band gap of around 3.94 eV. Additionally, the analysis of Nyquist plots (-Z'' vs. Z') shows that the electrical properties of the material are heavily dependent on frequency and temperature, indicating a relaxation phenomenon and semiconductor-type behavior. Reduction in Z' was observed as a function of temperature and frequency which indicates an increase in ac conductivity and the negative temperature coefficient of resistance. The frequency dependent plots of (-Z'') show that the electrical relaxation is non-Debye in nature. The ac conductivity spectrum obeys Jonscher's universal power law. The Correlated barrier hopping model CBH has been suggested to agree with the conduction mechanism of σ _ac for the [C₁₂H₁₇N₂]₂ZnBr₄ compound.

Optical-electrical properties and global reactivity analysis of aluminum phthalocyanine chloride

Global reactivity descriptors, Milliken’s charge distribution and molecular electrostatic potential based on Density Functional Theory (DFT), are used to understand the relationship between structure, stability and global chemical reactivity. In addition, these descriptors are used in the development of quantitative structure-activity and structure-property relationships. The study also shows the intense effect of the chlorine atom in the charge distribution. X-ray pattern reveals the crystalline structure along the (242) orientation of Aluminum Chloride phthalocyanine (AlCl-Pc) organic thin layer. Absorbance of such layer exhibits a high value within UV range and two consecutive peaks within visible range, spin coating is used to make an organic diode based on the AlCl-Pc cluster and the diode high rectifying facility is discovered. The height barrier is constant and saturation current is greatly reliant on light, the ideality factor of such a diode increases to 6.9 which confirms the non-ideality of such device.

A pilot study of single nucleotide polymorphisms in the interleukin-6 receptor and their effects on pre- and post-transplant serum mediator level and outcome after allogeneic stem cell transplantation

Interleukin (IL)-6 is an important regulator of immunity and inflammation in many diseases. Single nucleotide polymorphisms (SNPs) in the IL-6 gene influence outcome after allogeneic stem cell transplantation (ASCT), but the possible importance of SNPs in the IL-6 receptor has not been examined. We therefore investigated whether SNPs in the IL-6R gene influenced biochemical characteristics and clinical outcomes after ASCT. We examined the IL-6 promoter variant rs1800975 and the IL-6R SNPs rs4453032, rs2228145, rs4129267, rs4845374, rs4329505, rs4845617, rs12083537, rs4845618, rs6698040 and rs4379670 in a 101 population-based cohort of allotransplant recipients and their family donors. Patients being homozygous for the major alleles of the IL-6R SNPs rs2228145 and rs4845618 showed high pretransplant CRP serum levels together with decreased sIL-6R levels; the decreased IL-6R levels persisted 6 months post-transplant. In contrast, patients being homozygous for the minor allele of the IL-6R SNP rs4379670 showed decreased pretransplant CRP levels. Furthermore, the IL-6R rs4845618 donor genotype showed an association with severe acute graft-versus-host disease (GVHD), whereas the donor genotype of the IL-6 SNP rs1800795 was associated with decreased survival 100 days post-transplant. Finally, the recipient genotype of the IL-6R SNP rs4329505 showed a strong association with 2-years non-relapse mortality, and this effect was also highly significant in multivariate analysis. IL-6 and IL-6R SNPs influence the clinical outcome after allogeneic stem cell transplantation.

DFT computations on: Crystal structure, vibrational studies and optical investigations of a luminescent self-assembled material

The current work undertakes the growth and the physicochemical properties of a novel green-yellow luminescence semi-organic material, the 3-picolylammonium bromide abbreviated (Pico-Br). In this paper, we report the X-ray diffraction measurements which show that the crystal lattice consists of distinct 3-picolylammonium cations and free bromide anions connected via NH⋯Br and NH⋯N hydrogen bonds leading to form a two dimensional frameworks. Molecular geometry compared with its optimized counterpart shows that the quantum chemical calculations carried out with density functional method (DFT) well produce the perceived structure by X-ray resolution of the studied material. To provide further insight into the spectroscopic properties, additional characterization of this material have been performed with Raman and infrared studies at room temperature. Theoretical computations have been computed using the (DFT) method at B3LYP/LanL2DZ level of theory implemented within Gaussian 03 program to study the vibrational spectra of the investigated molecule in the ground state. Optical absorption spectrum inspected by UV-visible absorption reveals the appearance of sharp optical gap of 280nm (4.42eV) as well as a strong green photoluminescence emission at 550nm (2.25eV) is detected on the photoluminescence (PL) spectrum at room temperature. Using the TD/DFT method, HOMO-LUMO energy gap and the Mulliken atomic charges were calculated in order to get an insight into the material. Good agreement between the theoretical results and the experimental ones was predicted.

INTRAMEDULLARY TUBERCULOMA OF THORACIC SPINAL CORD IN AN APPARENTLY HEALTHY NIGERIAN: CASE REPORT

Spinal intramedullary is an uncommon form of tuberculosis causing spinal cord injury in this environment. We report a case of thoracic intramedullary tuberculoma in an immunocompetent male Nigerian with negative screening for tuberculosis. He presented with 8 months history of back pain and 2 months history of progressive weakness in both lower limbs. Physical examination revealed a well-nourished man with spastic paraplegia. Chest radiograph and CT scan were normal but Magnetic resonance imaging (MRI) of the thoracolumbar region showed cord oedema and circumscribed intramedullary lesions at D12 and L1 levels with target sign. The patient was promptly prepared and had D12 and L1 laminectomy and posterior myelotomy with excision of the intramedullary lesion. Histology showed granulomatous lesion with central caseation in keeping with a tuberculoma. He was treated with a 4-drug antituberculous regimen with physiotherapy and he made complete neurological recovery 8 months post-operatively. Intramedullary tuberculoma should be considered in differential diagnosis of intramedullary tumors in this environment. Treatment with antituberculous drugs results in good outcome.

Synthesis, crystal structure, vibrational spectroscopy, optical properties and theoretical studies of a new organic-inorganic hybrid material: [((CH3)2NH2)(+)]6·[(BiBr6)(3-)]2

A new organic-inorganic hybrid material, [((CH3)2NH2)(+)]6·[(BiBr6)(3-)]2, has been synthesized and characterized by X-ray diffraction, FT-IR, Raman spectroscopy and UV-Visible absorption. The studied compound crystallizes in the triclinic system, space group P1¯ with the following parameters: a=8.4749(6)(Å), b=17.1392(12)(Å), c=17.1392(12)(Å), α=117.339(0)°, β=99.487(0)°, γ=99.487(0)° and Z=2. The crystal lattice is composed of a two discrete (BiBr6)(3-) anions surrounded by six ((CH3)2NH2)(+) cations. Complex hydrogen bonding interactions between (BiBr6)(3-) and organic cations from a three-dimensional network. Theoretical calculations were performed using density functional theory (DFT) for studying the molecular structure, vibrational spectra and optical properties of the investigated molecule in the ground state. The full geometry optimization of designed system is performed using DFT method at B3LYP/LanL2DZ level of theory using the Gaussian03. The optimized geometrical parameters obtained by DFT calculations are in good agreement with single crystal XRD data. The vibrational spectral data obtained from FT-IR and Raman spectra are assigned based on the results of the theoretical calculations. The energy and oscillator strength calculated by Time-Dependent Density Functional Theory (TD-DFT) results complements with the experimental findings. The simulated spectra satisfactorily coincide with the experimental UV-Visible spectrum. The results show good consistent with the experiment and confirm the contribution of metal orbital to the HOMO-LUMO boundary.

Rome III subgroups of functional dyspepsia exhibit different characteristics of antral contractions measured by strain rate imaging - a pilot study

PURPOSE

Rome III defines two distinct entities of functional dyspepsia (FD), namely epigastric pain syndrome (EPS) and postprandial distress syndrome (PDS). We aimed at studying these subgroups of FD by simultaneously assessing antral strain, gastric accommodation and emptying and visceral hypersensitivity.

MATERIALS AND METHODS

Strain during antral contractions was assessed by ultrasound strain rate imaging in 15 controls and 19 FD patients (8 EPS patients and 11 PDS patients). Gastric accommodation and emptying were assessed using B-mode ultrasonography. Symptoms were assessed by visual analogue scale (VAS).

RESULTS

During fasting, antral strain in EPS patients (mean±SEM) was 61.4 ± 6.4 %, significantly higher than in controls (47.5 ± 3.3 %; p = 0.042) and in PDS patients (28.6 ± 1.7 %; p = 0.001). PDS patients had lower strain than controls (p < 0.001). Postprandially, EPS patients had higher strain than both controls and PDS patients (p < 0.01) but no difference was found between controls and PDS patients. Compared with controls, PDS patients had significantly larger fasting proximal area than controls (14.9 ± 1.6 cm2 vs. 7.8 ± 0.2 cm2; p < 0.001), whereas EPS patients did not differ (12.1 ± 1.9 cm2; p = 0.057). Gastric emptying fraction (1 - proximal area at 40 min postprandially/area at 1 min postprandial × 100) at 40 min postprandially in EPS patients 46.4 ± 6.6 % was lower than in controls (62.9 ± 1.3 %; p = 0.032), but higher than PDS patients (27.4 ± 5.3 %; p = 0.018).

CONCLUSION

Anterior radial strain measured by ultrasound strain rate imaging may discriminate between subgroups of FD and healthy controls. This study supports the Rome III classification of FD into EPS and PDS groups.

Structural, vibrational and DSC investigations of the bis-4-benzyl piperidinium tetraoxoselenate monohydrate crystal

A new organic-inorganic salt, bis-4-benzyl piperidinium tetraoxoselenate monohydrate has been synthesized and characterized by X-ray diffraction, FT-IR and FT-Raman spectroscopies. The title compound crystallizes in the monoclinic system P2(1)/c at room temperature with the following parameters: a=8.617(3)Å, b=27.140(9)Å, c=10.926(5)Å, β=96.46(4)° and Z=4. Its vibrational spectra have been discussed on the basis on quantum chemical density theory (DFT) calculation using B3LYP/6-31G(*) approach. The role of the intermolecular interaction in this crystal is analyzed. Acidic protons of the selenate group were transferred to the organic cation giving the singly-protonated cation. The ability of ions to form spontaneous three-dimensional structure through O-H···O and N-H···O hydrogen bond is fully utilized. These hydrogen bonds give notable vibrational effects.

Vibrational spectra and non linear optical proprieties of L-histidine oxalate: DFT studies

This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a nonlinear optical material L-histidine oxalate. Due to the lack of sufficiently precise information on geometric structure in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine oxalate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro symmetric space group P2(1)2(1)2(1) of orthorhombic system. The FT-IR and Raman spectra of L-histidine oxalate were recorded and analyzed. The vibrational wave numbers were examined theoretical with the aid of Gaussian98 package of programs using the DFT//B3LYP/6-31G(d) level of theory. The data obtained from vibrational wave number calculations are used to assign vibrational bands obtained in IR and Raman spectroscopy of the studied compound. The geometrical parameters of the title compound are in agreement with the values of similar structures. To investigate microscopic second order non-linear optical NLO behaviour of the examined complex, the electric dipole μ(tot), the polarizability α(tot) and the hyperpolarizability β(tot) were computed using DFT//B3LYP/6-31G(d) method. According to our calculation, the title compound exhibits non-zero β(tot) value revealing microscopic second order NLO behaviour.

Minor histocompatibility antigens in Tunisians: could platelet endothelial cell adhesion molecule 1 marker be one of them?

Platelet endothelial cell adhesion molecule 1 (PECAM-1/CD31) is one of the human minor histocompatibility antigens that are the main targets of alloreactive T-cells after hematopoietic stem cells or solid organs transplantation. In order to investigate its polymorphism in Tunisians, three single nucleotide polymorphisms (SNPs) (rs668, rs12953 and rs1131012) were selected to perform an allele and haplotype analysis. Hundred-and-forty-two healthy and unrelated subjects were enrolled in this survey. Genomic DNAs were extracted using salting out method. SNP genotyping assays were performed with home-designed sequence-specific primers polymerase chain reaction (SSP-PCR). As a result, molecular analysis showed that PECAM-1 is one of the most polymorphic markers in the Tunisian population because minor allele frequency was 0.3, and minimum haplotype frequency was 0.03. A low linkage disequilibrium (D' = 0.45) between rs12953 and rs1131012 was noticed, although all other loci were in the Hardy-Weinberg equilibrium (minimum P value = 0.07). The frequencies were close to those reported in African-American and Caucasian groups.

Molecular structure, vibrational spectra and nonlinear optical properties of orthoarsenic acid-tris-(hydroxymethyl)-aminomethane DFT study

In this work, we report a theoretical study on molecular structure, vibrational spectra and nonlinear optical properties of orthoarsenic acid-tris-(hydroxymethyl)-aminomethane (OATA). The theoretical geometrical parameters in the ground state have been investigated by density functional method (B3LYP and BLYP) with 6-311G(d,p) basis set. The influence of intermolecular interactions effects on molecular properties has been considered by calculation performed on (OATA) dimer. The optimized geometric bond lengths and bond angles are in well agreement with the experimental data. As compared to theoretical frequencies of the monomer, the calculated values obtained for (OATA) dimer are in much better agreement with the experiment. All experimental vibrational bands have been discussed and assigned to normal modes on the basis of our theoretical calculations. B3LYP method has shown better fit to experimental ones than BLYP in calculation vibrational frequencies. To investigate nonlinear optical behaviour, the electric dipole moment mu, the polarizability alpha and the hyperpolarizability beta were computed using DFT//B3LYP/6-311G(d,p) method.

Crystal studies, vibrational spectra and non-linear optical properties of L-histidine chloride monohydrate

This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a non-linear optical material L-histidine chloride monohydrate. Due to the lack of sufficiently precise information on geometric parameters available in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine chloride monohydrate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro-symmetric space group P2(1)2(1)2(1) of orthorhombic system. IR spectrum has been recorded in the range [400-4000 cm(-1)]. All the experimental vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our calculations. The optimized geometric bond lengths and bond angles obtained by using DFT//B3LYP/6-31G (d) method show a good agreement with the experimental data. The calculated vibrational spectra are in well agreement with the experimental one. To investigate microscopic second-order non-linear optical NLO behavior of the examined complex, the electric dipole mu, the polarizability alpha and the hyperpolarizability beta were computed using DFT//B3LYP/6-31G (d) method. The time-dependent density functional theory (TD-DFT) was employed to descript the molecular electron structure of the title compound using the B3LYP/6-31G (d) method. According to our calculations, L-histidine chloride monohydrate exhibits non-zero beta value revealing microscopic second-order NLO behavior.

Strain measurement during antral contractions by ultrasound strain rate imaging: influence of erythromycin

Strain rate imaging (SRI) is a non-invasive ultrasound (US) modality that enables the study of mechanical deformation (strain) with high spatial and temporal resolution. A total of 244 contractions in seven healthy volunteers were studied by SRI on two separate days to characterize radial strain of antral contractions in the fasting and fed states and to assess the influence of intravenous erythromycin. Gastric accommodation and emptying were assessed by 2D ultrasonography. The perception of hunger was registered by the participants. The strain increased from early to late phase II and phase III activity by (median) 18%, 58% and 82%, respectively, P < 0.05. Erythromycin infusion in phase I induced contractions with median strain of 35%, but did not increase postprandial strain. Both fasting and postprandially, lumen-occlusive contractions with erythromycin were more frequent than in naturally occurring contractions, 69%vs 48%, P = 0.036 and 40%vs 5%, P < 0.001 respectively. All subjects had rumbling in their abdomens when intraluminal air was detected sonographically (85% of all phase III contractions) and that rumbling was perceived by the participant as maximal awareness of hunger. SRI enabled detailed strain measurement of individual antral contractions. Erythromycin initiated fasting antral contractions and increased the number of lumen-occlusive contractions.

The effect of metformin on blood glucose control in overweight patients with Type 1 diabetes

AIMS

In a randomized, double-blind, cross-over study, we investigated the effect of metformin on blood glucose control and daily insulin dose in overweight patients with Type 1 diabetes.

METHODS

We studied 15 C-peptide-negative patients, aged 48 +/- 12 years, with a body mass index of 31.3 +/- 2.6 kg/m(2). Each patient had a 'screening visit', followed by a 4-week 'run-in' period. This was followed by two separate 16-week 'study' (treatment) periods, separated by a 4-week 'wash-out' period. Patients received either metformin or placebo during the 'study' periods, in random order.

RESULTS

HbA(1c) was significantly lower following 16 weeks of treatment with metformin (7.8 +/- 1.1%) compared with baseline (8.5 +/- 1.4%; P < 0.005) and placebo (8.6 +/- 1.2%; P < 0.005). Fasting plasma glucose, following 16 weeks of metformin treatment, was significantly lower (8.3 +/- 2.8 mmol/l) compared with baseline (12.4 +/- 3.0 mmol/l; P < 0.01) and placebo (12.6 +/- 3.4 mmol/l; P < 0.01). Compared with baseline (60 +/- 14 units), total daily insulin dose was significantly lower following the addition of metformin (50 +/- 13 units; P < 0.05) and this final total daily insulin dose in the metformin group was lower compared with placebo (58 +/- 12 units, P < 0.05). Body weight did not change following metformin or placebo treatment.

CONCLUSION

Metformin can effectively improve glycaemic control and reduce the total daily insulin dose in overweight people with Type 1 diabetes.

A survey of peri-operative use of magnesium sulphate in adult cardiac surgery in the UK

We conducted a postal survey of cardiac anaesthetists in the UK, to determine the extent of magnesium sulphate (MgSO4) use and the main indications for its administration. Questionnaires were sent to anaesthetists at 35 UK hospitals undertaking adult cardiac surgery. Responses were received from 24 hospitals (69%) totalling 124 individual responses. Twenty-five (20%) of the anaesthetists responding to the questionnaire routinely gave magnesium other than in cardioplegia. The most common indications for administration were arrhythmia prophylaxis and treatment, myocardial protection, and the treatment of hypomagnesaemia.

Tracheal intubation through the laryngeal mask airway using a gum elastic bougie: the effect of head position

STUDY OBJECTIVE

To determine the effect of head position on success of tracheal intubation through a Laryngeal Mask Airway (LMA) using a gum elastic bougie.

DESIGN

Randomized, controlled study.

SETTING

Anesthesia and operating rooms of the University Hospital, Nottingham, UK.

PATIENTS

20 patients scheduled to undergo routine elective surgery requiring the use of an LMA for anesthesia.

INTERVENTIONS

Blind placement of a gum elastic bougie through an LMA in two head positions.

MEASUREMENTS AND MAIN RESULTS

Final position of the gum elastic bougie after removal of the LMA as determined by fiberoptic laryngoscopy. The gum elastic bougie was correctly sited in the trachea in the classical intubating position in 4/20 (20%) and in the neutral position in 0/20 (0%). There was no difference in the success of this technique between the two head positions.

CONCLUSIONS

This technique cannot be recommended as an alternative to direct laryngoscopy following a failed intubation.

Cardiac output during hemiarthroplasty of the hip. A prospective, controlled trial of cemented and uncemented prostheses

In a prospective, controlled study, we measured the effect on cardiac output of the introduction of methylmethacrylate during hemiarthroplasty for displaced fractures of the femoral neck. We treated 20 elderly patients who were similar in age, height, weight and preoperative left ventricular function with either cemented or uncemented hemiarthroplasty. Using a transoesophageal Doppler probe, we measured cardiac output before incision and at six stages of the procedure: during the surgical approach, reaming and lavage of the femoral canal, the introduction of cement, the insertion of the prosthesis, and in reduction and closure. We found that before the cement was introduced, there was no difference in stroke volume or cardiac output (p > 0.25). Cementation produced a transient but significant reduction in cardiac output of 33% (p < 0.01) and a reduction in stroke volume of 44% (p < 0.02). The introduction of cement did not affect the heart rate or mean arterial pressure. There was no significant difference in cardiac function on insertion of the prosthesis. Standard non-invasive haemodynamic monitoring did not detect the cardiovascular changes which may account for the sudden deaths that sometimes occur during cemented hemiarthroplasty. The fall in stroke volume and cardiac output may be caused by embolism occurring during cementation, but there was no similar fall during reaming or insertion of the prosthesis.

Antimicrobial agent resistance in bacterial isolates from patients with diarrhea and urinary tract infection in the Sudan

Antimicrobial sensitivity tests were performed on four-hundred and ninety-seven bacterial isolates from Sudanese patients with diarrhea or urinary tract infections. Shigella dysenteriae type I and enteropathogenic Escherichia coli showed high resistance rates (percentage of isolates showing antibiotic resistance) against the commonly-used antimicrobial agents: ampicillin, amoxicillin, chloramphenicol, tetracycline, cotrimoxazole, nalidixic acid, sulfonamide, and neomycin, and were completely sensitive to ciprofloxacin. Eighteen resistance patterns against nine antimicrobial agents tested were observed in enteric pathogens. Resistance to ampicillin, amoxicillin, tetracycline, cotrimoxazole, and sulfonamide was the most frequent pattern. The common urinary pathogens, E. coli, Klebsiella pneumoniae, and Proteus mirabilis showed high rates of resistance to ampicillin, amoxicillin, cotrimoxazole, tetracycline, sulfonamide, trimethoprim, streptomycin, and carbenicillin. We recommend that physicians seek updated knowledge of the common antibiotic-sensitivity patterns when starting empirical antibiotic therapy in Sudanese patients with diarrhea or urinary tract infection.

Randomized, placebo-controlled trial of combination antiemetic prophylaxis for day-case gynaecological laparoscopic surgery

In a randomized, double-blind trial, we compared i.v. ondansetron 4 mg (control), i.v. ondansetron 4 mg and cyclizine 50 mg (combination) and i.v. saline 0.9% (placebo), given after induction of standardized anaesthesia, for the prevention of nausea and vomiting (PONV) after day-case gynaecological laparoscopic surgery. Compared with placebo, fewer patients in the control group vomited (9/20 versus 11/59, P = 0.02) or needed rescue antiemetic (7/20 versus 9/59, P = 0.06) before discharge. Compared with the control, fewer patients in the combination group (n = 60) vomited (11/59 versus 2/60, P = 0.01) or needed rescue antiemetic (29/59 versus 2/60, P = 0.03) before discharge. The incidence of vomiting in the combination group was less than 5% overall. Compared with the control, the combination group had a significantly lower incidence (P = 0.001) and severity (P < 0.001) of nausea after discharge and more patients with no PONV at any time during the study (15/59 versus 27/60, P = 0.03). Unlike the placebo and control groups, no patient receiving combination prophylaxis was admitted overnight for PONV management.

Cardiovascular pharmacology: new drugs and new indications

This review presents a brief overview of some of the many exciting developments that are taking place in the field of cardiovascular pharmacology. Research continues to progress at a rapid rate, and we can expect many drugs to enter the clinical arena within the next few years. It must be borne in mind, however, that the pharmaceutical industry and hospital budgetary restrictions sometimes limit drug development and occasionally interrupt clinical trials, even before their results have been obtained.

Optimal provision of daytime NPH insulin in patients using the insulin analog lispro

OBJECTIVE

Insulin lispro improves early postprandial blood glucose control but can result in late interprandial hyperglycemia. As an approach to resolving this problem, we performed a randomized, crossover study with four treatment arms, comparing the daytime metabolic profile after either premeal lispro alone or premeal lispro with optimal daytime NPH insulin and with standard human regular insulin.

RESEARCH DESIGN AND METHODS

Twelve C-peptide negative type 1 diabetic patients were studied on four separate study days, at least 7 days apart. On each study day, patients received one of the four study insulin treatments, in random order, with identical meals and snacks. The four treatments were 1) premeal human regular insulin before lunch and supper at unchanged dose; 2) premeal lispro (unchanged dose) at lunchtime and dinner; 3) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 6-h interval until dinner; and 4) pre-lunch reduced-dose lispro (70%) before lunch and supper with supplemental lunchtime NPH and with a 8-h interval until dinner. All patients were using their usual premeal plus basal insulin regimen during the period of the study, with human regular insulin before meals and NPH insulin at bedtime.

RESULTS

Postprandial blood glucose concentrations (1230-1500) were lower after reduced or usual lispro dose compared with human regular insulin (5.5+/-0.2 and 5.6+/-0.2 vs. 8.2+/-0.5 mmol/l, P < 0.001), with no difference between the lispro doses. However, prepran-Dial (1800) blood glucose levels deteriorated to higher levels after usual-dose lispro alone compared with either human regular insulin (P < 0.05) or reduced-dose lispro plus NPH (P < 0.05) (8.9+/-0.3 vs. 7.1+/-0.8 and 6.4+/-0.4 mmol/l), with no difference between human regular insulin and reduced-dose lispro plus NPH. During the 2 h between the usual and delayed mealtime, blood glucose concentrations remained controlled on lispro plus NPH (2000: 6.5+/-0.4 mmol/l).

CONCLUSIONS

Reduced-dose lunchtime lispro plus NPH maintained the improvement in postprandial blood glucose control with no deterioration in interprandial blood glucose control, even up to a late meal.

A physiology simulator: validation of its respiratory components and its ability to predict the patient's response to changes in mechanical ventilation

We aimed to validate the mathematical validity and accuracy of the respiratory components of the Nottingham Physiology Simulator (NPS), a computer simulation of physiological models. Subsequently, we aimed to assess the accuracy of the NPS in predicting the effects of a change in mechanical ventilation on patient arterial blood-gas tensions. The NPS was supplied with the following measured or calculated values from patients receiving intensive therapy: pulmonary shunt and physiological deadspace fractions, oxygen consumption, respiratory quotient, cardiac output, inspired oxygen fraction, expired minute volume, haemoglobin concentration, temperature and arterial base excess. Values calculated by the NPS for arterial oxygen tension and saturation (PaO2 and SaO2), mixed venous oxygen tension and saturation (PvO2 and SvO2), arterial and mixed venous carbon dioxide tension (PaCO2 and PvCO2) and arterial pH were accurate compared with measured values. Subsequently, arterial gas responses to changes in minute volume of FiO2 were measured in 31 patients and were compared with the NPS prediction for each response. The 95% limits of agreement in predicting the magnitude of change were: arterial oxygen tension -2.07 to 2.47 kPa; PaCO2 -0.33 to 0.67 kPa; and pH -0.023 to 0.033. This investigation has validated respiratory components of the NPS. We recommend the NPS as a clinical tool for predicting the effects of alterations in mechanical ventilation in stable patients in the intensive care unit.

Optimization of evening insulin dose in patients using the short-acting insulin analog lispro

OBJECTIVE

A three-way, crossover, open-label, randomized study was designed to compare the evening and night (1800-0800) glycemic control when the evening premeal lispro dose was reduced by 20% and the bedtime basal NPH dose increased by 25%, or when the basal NPH dose was moved to before dinner at 1800, compared with the control arm on standard premeal human regular insulin and pre-bedtime NPH insulin.

RESEARCH DESIGN AND METHODS

A total of 13 type 1 diabetic patients who use a premeal plus basal insulin regimen were studied on three separate days, with identical meals and snacks at the same times on each study day. On the control study day, patients received human regular insulin before dinner and NPH at bedtime in their usual doses. On another day, lispro was given before dinner with a dose reduction of 20%, and NPH at bedtime at 125% of usual dose. In the third regimen, the lispro and NPH were administered together in their usual dose before the evening meal by separate injections. The three regimens were tested in random order.

RESULTS

Postprandial (1800-2200) blood glucose concentrations were lower after reduced-dose lispro compared with human regular insulin (6.0 +/- 0.3 [SEM] vs. 7.4 +/- 0.3 mmol/l, P < 0.05). Nighttime (2400-0400) blood glucose concentrations were not different (8.6 +/- 0.3 vs. 9.2 +/- 0.3 mmol/l, NS), and prebreakfast concentrations were also unchanged (7.7 +/- 0.9 vs. 8.7 +/- 0.8 mmol/l) after lispro with increased-dose NPH compared with standard insulin. By contrast, both nighttime (10.0 +/- 0.3 mmol/l, P < 0.05) and fasting glucose concentrations (10.8 +/- 0.6 mmol/l, P < 0.05) were significantly higher with dinnertime usual-dose lispro plus dinnertime usual-dose NPH compared with standard human insulin. Hypoglycemia at night (blood glucose < 3.0 mmol/l) did not differ between study days, but it was more frequent postprandially after dinner usual-dose lispro plus early NPH (2 vs. 7 patients, P = 0.062).

CONCLUSIONS

With lower mealtime and higher basal bedtime insulin doses, patients using insulin lispro may be able to gain an overall improvement in evening blood glucose control without deteriorated nighttime glucose levels. Earlier basal NPH dosage alone does not ameliorate the nighttime hyperglycemia of short-acting insulin analog regimens.

The effect of the insulin analog lispro on nighttime blood glucose control in type 1 diabetic patients

OBJECTIVE

Unmodified regular insulin has a long absorption tail, unlike the fast-acting insulin analog lispro, and may contribute to hypoglycemia in the early part of the night. A randomized crossover double-blind study was performed to compare blood glucose concentrations in the early part of the night in type 1 diabetic patients receiving lispro or unmodified regular human insulin, in random order, on 2 separate study days.

RESEARCH DESIGN AND METHODS

We studied 23 C-peptide-negative patients; 12 were using a premeal plus basal insulin regimen, and 11 were using twice-daily insulin injections. Patients were admitted to the investigation unit at 5:00 P.M. and received a single dose of lispro or unmodified regular human insulin before the evening meal. In both groups, the NPH insulin dose remained unchanged. Identical meals and snacks were eaten at the same time during both study days.

RESULTS

Average postprandial (6:00-10:00 P.M.) blood glucose concentrations were significantly lower after lispro therapy compared with human insulin (7.1 +/- 0.4 [SE] vs. 8.5 +/- 0.4 mmol/l, P = 0.0002). Nighttime (midnight to 4:00 A.M.) blood glucose concentrations were significantly higher after lispro compared with human insulin (10.3 +/- 0.4 vs. 9.1 +/- 0.4 mmol/l, P = 0.02). This difference was greatest in patients on the premeal plus basal insulin regimen (11.6 +/- 0.5 vs. 8.7 +/- 0.4 mmol/l, P < 0.001). The incidence of nocturnal hypoglycemia (midnight to 4:00 A.M., blood glucose < 3.5 mmol/l) was less with lispro compared with unmodified insulin (1 vs. 6 patients, P = 0.04). Nighttime (midnight to 4:00 A.M.) 3-hydroxybutyrate (102 +/- 13 vs. 51 +/- 7 mumol/l, P = 0.000) and glycerol (52 +/- 3 vs. 42 +/- 2 mumol/l, P < 0.01) were significantly higher after lispro therapy compared with human insulin in patients on the premeal plus bolus insulin regimen.

CONCLUSIONS

Lispro can improve postprandial blood glucose control and reduce the incidence of nocturnal hypoglycemia at the expense of nocturnal hyperglycemia and hyperketonemia in patients using a premeal plus basal insulin regimen.

Anaesthetic management of a quadriplegic patient with severe respiratory insufficiency undergoing caesarean section

The anaesthetic management of a 30-year-old pregnant quadriplegic patient with severe respiratory insufficiency undergoing Caesarean section is described. Quadriplegia and respiratory insufficiency pose potential problems for anaesthetists and these are discussed. In particular autonomic hyperreflexia may occur and this may be mistaken for pre-eclampsia.

Toxoplasma gondii in Saudi blood donors a serological study using three tests

A total of one hundred and fifty Saudi blood donors were examined for Toxoplasma gondii antibodies (IgG-IgM) by three serological techniques, 50 normal cross matched controls were subjected to the same examination. The number of positive donors for IgG by Indirect Haemagglutination test (IHA) was 36 (24%), by Enzyme Linked Immunosorbent Assay (ELISA) was 70 (46.7%), and by Immunofluorescent test (IFAT) 74 (49.3%). As to IgM the ELISA and IFAT showed 3 positive cases among the blood donors (2%). Rheumatoid factor and antinuclear antibodies were done for positive cases, and showed no significant cross reaction, IgG antibodies were significantly high in donors than in controls. The three tests were more or less dependable. However regarding simplicity, specificity, accuracy and time consumption factor IFAT was recommended for Toxoplasma IgG for all blood donors to avoid the risk of in infection.

Sensitivity of LiF thermoluminescent dosemeters to 6-18 keV photons

The sensitivity of thermoluminescent dosemeters (TLD) to 6-18 keV photons at six different effective energies was determined using an extrapolation chamber as a dosimetric standard. Photons having effective energies of 8.1, 9.2, 13.5, 13.8 and 18.0 keV were generated from an x-ray machine using appropriate kilovoltages and aluminium filters. Photons from an 55Fe source (6 keV) were also used to broaden the range of energies investigated. Observed sensitivities relative to 137Cs were found not to differ from unity with the possible exception of 6.0 keV photons. At 6.0 keV the sensitivity was found to be 0.83 +/- 0.5.

Scales for measuring mania

This paper examines the utility of two scales for mania and the statistical validity of their use in a clinical setting. The literature is reviewed in regard to the present evaluation of accurate clinical scales in this area.

Tetracycline prophylaxis in families of cholera patients

The evaluation of tetracycline as a chemoprophylactic agent for cholera is described. Families of cholera patients were divided into 4 groups by strict rotation. The first group received multivitamin preparations and served as the control. The second received 1.0 g of tetracycline, divided into 4 doses, daily for 5 days, the third received 1.0 g of tetracycline in a single dose daily for 5 days, and the fourth received a single dose of 1.0 g of tetracycline. All families were visited daily for 10 days, a rectal swab being taken from each family member on each occasion. Tetracycline given daily for 5 days, either in divided doses or in a single daily dose, was effective in preventing subsequent infection. A single dose of tetracycline was less effective. The indications for chemoprophylaxis in cholera are discussed.

Increased plasma arginine vasopressin in clinical adrenocortical insufficeincy and its inhibition by glucosteroids

Trichloroacetic acid extracts of plasma were fractionated on a CG-50 resin column and the 50% acetic acid eluents chromatographed on silicic acid-impregnated glass paper in butanol-acetic acid-water. The specific arginine vasopressin (AVP) zone was eluted and assayed for antidiuretic activity in the diuretic rat. Thioglycolate inactivation was used to confirm AVP activity. Recovery of as little as 4 muU AVP per ml plasma ranged between 80 and 90%. In normal subjects after an overnight fast, plasma AVP ranged between 2.5 and 10.0 muU per ml. AVP secretion was inhibited by hemodilution and stimulated with nicotine and hypertonic saline. Plasma AVP was absent in patients with diabetes insipidus even after neurohypophyseal stimulation. Plasma AVP was abnormally elevated during mild dehydration and remained above the normal range despite hemodilution in patients with untreated adrenocortical insufficiency demonstrating a delayed water diuresis. Glucosteroid therapy lowered plasma AVP to normal in dehydrated patients. A normal diuretic response to hydration was accompanied by a fall in plasma AVP to zero in steroid-treated patients. These findings suggest that hypersecretion of AVP may play an important role in the abnormal water metabolism of adrenocortical insufficiency and that the glucosteroids promote normal water diuresis by inhibiting the secretion of AVP from the neurohypophysis.