1
|
Measurement of the fluorescence lifetime of GFP in high refractive index levitated droplets using FLIM. Phys Chem Chem Phys 2020; 22:14704-14711. [PMID: 32573569 DOI: 10.1039/c9cp06395a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Green fluorescent protein (GFP) is a widely used fluorescent probe in the life sciences and biosciences due to its high quantum yield and extinction coefficient, and its ability to bind to biological systems of interest. This study measures the fluorescence lifetime of GFP in sucrose/water solutions of known molarity in order to determine the refractive index dependent lifetime of GFP. A range of refractive indices from 1.43-1.53 were probed by levitating micron sized droplets composed of water/sucrose/GFP in an optical trap under well-constrained conditions of relative humidity. This setup allows for the first reported measurements of the fluorescence lifetime of GFP at refractive indices greater than 1.46. The results obtained at refractive indices less than 1.46 show good agreement with previous studies. Further experiments that trapped droplets of deionised water containing GFP allowed the hygroscopic properties of GFP to be measured. GFP is found to be mildly hygroscopic by mass, but the high ratio of molecular masses of GFP to water (ca. 1500 : 1) signifies that water uptake is large on a per-mole basis. Hygroscopic properties are verified using brightfield microscope imaging, of GFP droplets at low and high relative humidity, by measuring the humidity dependent droplet size. In addition, this experiment allowed the refractive index of pure GFP to be estimated for the first time (1.72 ± 0.07). This work provides reference data for future experiments involving GFP, especially for those conducted in high refractive index media. The work also demonstrates that GFP can be used as a probe for aerosol studies, which require determination of the refractive index of the aerosol of any shape.
Collapse
|
2
|
1064 nm Dispersive Raman Microspectroscopy and Optical Trapping of Pharmaceutical Aerosols. Anal Chem 2018; 90:8838-8844. [PMID: 29956916 DOI: 10.1021/acs.analchem.8b00817] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Raman spectroscopy is a powerful tool for investigating chemical composition. Coupling Raman spectroscopy with optical microscopy (Raman microspectroscopy) and optical trapping (Raman tweezers) allows microscopic length scales and, hence, femtolitre volumes to be probed. Raman microspectroscopy typically uses UV/visible excitation lasers, but many samples, including organic molecules and complex tissue samples, fluoresce strongly at these wavelengths. Here we report the development and application of dispersive Raman microspectroscopy designed around a near-infrared continuous wave 1064 nm excitation light source. We analyze microparticles (1-5 μm diameter) composed of polystyrene latex and from three real-world pressurized metered dose inhalers (pMDIs) used in the treatment of asthma: salmeterol xinafoate (Serevent), salbutamol sulfate (Salamol), and ciclesonide (Alvesco). For the first time, single particles are captured, optically levitated, and analyzed using the same 1064 nm laser, which permits a convenient nondestructive chemical analysis of the true aerosol phase. We show that particles exhibiting overwhelming fluorescence using a visible laser (514.5 nm) can be successfully analyzed with 1064 nm excitation, irrespective of sample composition and irradiation time. Spectra are acquired rapidly (1-5 min) with a wavelength resolution of 2 nm over a wide wavenumber range (500-3100 cm-1). This is despite the microscopic sample size and low Raman scattering efficiency at 1064 nm. Spectra of individual pMDI particles compare well to bulk samples, and the Serevent pMDI delivers the thermodynamically preferred crystal form of salmeterol xinafoate. 1064 nm dispersive Raman microspectroscopy is a promising technique that could see diverse applications for samples where fluorescence-free characterization is required with high spatial resolution.
Collapse
|
3
|
Cloud condensation nucleation activities of calcium carbonate and its atmospheric ageing products. Phys Chem Chem Phys 2015; 17:32194-203. [PMID: 26578034 DOI: 10.1039/c5cp03795f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Aerosol particles can serve as cloud condensation nuclei (CCN) to form cloud droplets, and its composition is a main factor governing whether an aerosol particle is an effective CCN. Pure mineral dust particles are poor CCN; however, changes in chemical composition of mineral dust aerosol particles, due to heterogeneous reactions with reactive trace gases in the troposphere, can modify their CCN properties. In this study we investigated the CCN activities of CaCO3 (as a surrogate for mineral dust) and its six atmospheric ageing products: Ca(NO3)2, CaCl2, CaSO4, Ca(CH3SO3)2, Ca(HCOO)2, and Ca(CH3COO)2. CaCO3 has a very low CCN activity with a hygroscopicity parameter (κ) of 0.001-0.003. The CCN activities of its potential atmospheric ageing products are significantly higher. For example, we determined that Ca(NO3)2, CaCl2 and Ca(HCOO)2 have κ values of ∼0.50, similar to that of (NH4)2SO4. Ca(CH3COO)2 has slightly lower CCN activity with a κ value of ∼0.40, and the κ value of CaSO4 is around 0.02. We further show that exposure of CaCO3 particles to N2O5 at 0% relative humidity (RH) significantly enhances their CCN activity, with κ values increasing to around 0.02-0.04. Within the experimental uncertainties, it appears that the variation in exposure to N2O5 from ∼550 to 15,000 ppbv s does not change the CCN activities of aged CaCO3 particles. This observation indicates that the CaCO3 surface may be already saturated at the shortest exposure. We also discussed the atmospheric implications of our study, and suggested that the rate of change in CCN activities of mineral dust particles in the troposphere is important to determine their roles in cloud formation.
Collapse
|
4
|
RSV-associated hospitalizations in Alaska Native infants. Int J Circumpolar Health 1999; 57 Suppl 1:255-9. [PMID: 10093285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
PURPOSE Retrospective reviews for 1986-1992 suggested that Alaska Native children experience high rates of respiratory syncytial virus (RSV)-associated hospitalization; however, the epidemiology of RSV infections has been poorly characterized. METHODS A prospective hospital-based surveillance study was undertaken to determine rates of RSV-associated hospitalization in Alaska Native children < 36 months from the Yukon-Kuskokwim Delta. RESULTS During the first study year, October 1993 to September 1994, there were 40 RSV cases (hospitalization rate, 53/1,000 infants < 1 year of age); however, during the second year, October 1994 to September 1995, there were 251 RSV cases (hospitalization rate, 294/1,000 infants). An unusually high proportion, 12%, of RSV cases were < 1 month of age. Disease severity was higher for children with a history of prematurity, heart, or lung disease (p = .001, X2 analysis). Of 255 cell cultures during 1994-1995, 190 were RSV-positive, 11 were positive for influenza, 4 for adenovirus, and 1 for parainfluenza. This study demonstrates wide seasonal variation in a population with an extremely high RSV hospitalization rate; increased disease severity associated with young age and pre-existing medical conditions; and co-circulation of RSV with other viruses.
Collapse
|
5
|
|
6
|
Constitutional mass torts: sovereign immunity and the human radiation experiments. COLUMBIA LAW REVIEW 1996; 96:1203-1251. [PMID: 12568077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
|
7
|
|
8
|
Abstract
Kikuchi-Fujimoto disease (KFD) has been widely reported from Japan and sporadically from many parts of the world including Saudi Arabia, since its original description in 1972 but the disease remains poorly known by clinicians. In this paper we report two Saudi patients seen in Tabuk, Saudi Arabia. One was a 36-year-old Saudi man and the other a 16-year-old Saudi girl. Both presented with cervical lymphadenopathy and pyrexia. Histological examination of biopsy material from both showed classical features of KFD. Other laboratory findings were unremarkable except for leucopenia. Following excision biopsy both patients recovered without sequelae. KFD is a self-limiting process of uncertain aetiology that predominantly affects young women aged 20-30 years. We review the pathology, clinical featuers and possible aetiology of this interesting disease, which may well be underdiagnosed. Increased awareness of KFD will minimize the risk of confusing this entity with malignant lymphoma or other serious conditions.
Collapse
|
9
|
Decline of Haemophilus influenzae type b disease in a region of high risk: impact of passive and active immunization. Pediatr Infect Dis J 1994; 13:362-7. [PMID: 8072817 DOI: 10.1097/00006454-199405000-00006] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Haemophilus influenzae type b (Hib) is a major cause of serious childhood bacterial infections. Before 1989 Alaska Native infants in the Yukon Kuskokwim Delta (YKD) had the highest recorded Hib disease rate, 2960:100,000 in children less than 1 year of age with 6 to 35 (mean, 13) cases/year between 1980 and 1988. In July, 1989, Alaska Area Native Health Service initiated a passive immunization project in the YKD using bacterial polysaccharide immunoglobulin (BPIG) administered at 3-month intervals to prevent Hib infections in infants less than 13 months of age. On January 1, 1991, after licensure of Hib conjugate vaccines for infants, the program was modified to a passive-active strategy using BPIG at birth and PedvaxHIB at 2, 4 and 12 months of age. Between July 1, 1989, and December 31, 1990, 80% of YKD children less than 1 year of age received at least 1 dose of BPIG. During this period there were 7 Hib cases in this age group, but only 1 of the cases had received any BPIG. Between January 1, 1991, and December 31, 1992, 4 Hib cases occurred in 2 YKD children. During the combined period, July 1, 1989, to December 31, 1992, the incidence of Hib disease for infants less than 1 year of age was 302:100,000. A dramatic decrease in Hib disease was observed in this high incidence region concurrent with implementation of passive and passive-active immunization strategies.
Collapse
|
10
|
Games: teaching strategy for professionals. DIABETES EDUCATOR 1989; 15:532-3. [PMID: 2627870 DOI: 10.1177/014572178901500612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
11
|
Peripartum cardiac failure. A ten year follow-up study. TROPICAL AND GEOGRAPHICAL MEDICINE 1989; 41:190-6. [PMID: 2595796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A cohort of patients with peripartum cardiac failure (PPCF) was followed for 10 years after the initial illness. The follow up rate was 78%. Fifty two per cent of patients improved without further episodes of heart failure. PPCF recurred in 26 per cent. Heart failure unrelated to pregnancy was seen in 13%, and 9% of the patients progressed to dilated cardiomyopathy. Transient hypertension was seen in 87% of patients on admission, and later hypertension was found in 45%. Late hypertension influenced heart size more when recurrent PPCF or progressive heart failure was present. Anaemia on admission had no effect on subsequent heart size. The electrocardiogram may continue to be abnormal for up to 10 years in normotensive patients who had no heart failure. The abnormal electrocardiogram in patients with persistent cardiomegaly may represent progressive myocardial damage. Mortality rate was highest (11%) in the first year and declined thereafter. Cardiac deaths were common in patients with recurrent PPCF or progressive heart failure.
Collapse
|
12
|
|
13
|
|
14
|
Abstract
A case of a woman on tocainide who developed abnormal liver function. A causal relationship is postulated.
Collapse
|
15
|
|
16
|
Abstract
Peripheral white and red blood cell changes were studied in response to acute insulin-induced hypoglycaemia in six normal, six splenectomized and five sympathectomized (tetraplegic) subjects. The normal subjects were restudied during beta (propranolol) and beta 1-selective (metoprolol) adrenergic blockade. In the normal subjects a lymphocytosis immediately followed the acute hypoglycaemic reaction (R) with a neutrophilia 2 h later. The early lymphocytosis was absent in sympathectomized subjects (P less than 0.001) and reduced under beta blockade (P less than 0.02) in normal subjects, indicating mediation via an adrenergic mechanism. The later neutrophilia from R + 60 min was not abolished by adrenergic blockade or preceding sympathectomy; the enhanced response with propranolol was associated with an elevated plasma cortisol. Haemoglobin, packed cell volume and total erythrocyte count rose maximally at R in all groups except the sympathectomized subjects in whom all parameters declined progressively from basal values. These peripheral erythrocytes changes appear to be mediated via an adrenergic mechanism which is unaffected by beta adrenergic blockade and which does not involve splenic contraction.
Collapse
|
17
|
|
18
|
Abstract
1. The effects of insulin-induced hypoglycaemia on pupil size, parotid salivary secretion and sweating were studied in seven normal volunteers. 2. Hypoglycaemia was associated with an acute stimulation of parotid salivary secretion and of sweating, synchronous in onset with the rise in heart rate. There was no clear evidence of concurrent pupillary constriction.
Collapse
|
19
|
|
20
|
Hormonal and substrate responses during recovery from hypoglycaemia in man during beta 1-selective and non-selective beta-adrenergic blockade. Eur J Clin Invest 1981; 11:279-83. [PMID: 6795044 DOI: 10.1111/j.1365-2362.1981.tb02117.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Recovery from acute hypoglycaemia induced by the injection of insulin has been examined in six human subjects under control conditions, under non-selective beta blockade (propranolol) and under selective beta 1 blockade (metoprolol). The normal blood glucose recovery was biphasic with an initial rapid and a slower subsequent phase of recovery. The early recovery mechanism was unaffected by either form of beta blockade, but with propranolol the late phase of recovery was significantly prolonged. Rises in blood lactate and plasma free fatty acids following hypoglycaemia were markedly reduced by propranolol but to a much lesser degree with metoprolol. The counterregulatory hormonal responses of glucagon, cortisol and growth hormone were augmented appropriately for the prolonged hypoglycaemia associated with propranolol. Non-selective beta adrenergic blockade with propranolol is associated with an impairment of the late phase of blood glucose recovery from hypoglycaemia. The possible mechanisms of this impairment are discussed.
Collapse
|
21
|
|
22
|
Withdrawal of cyanocobalamin. BRITISH MEDICAL JOURNAL 1979; 2:1219-20. [PMID: 519368 PMCID: PMC1597301 DOI: 10.1136/bmj.2.6199.1219-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
23
|
Training of doctors in developing countries. Lancet 1979; 2:642. [PMID: 90309 DOI: 10.1016/s0140-6736(79)91705-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
24
|
|
25
|
Peri-partum cardiac failure. THE QUARTERLY JOURNAL OF MEDICINE 1978; 47:431-61. [PMID: 751087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The syndrome of peri-partum cardiac failure (PPCF) has been studied in 224 women seen in three years in Zaria, in northern Nigeria. A very high proportion were rural Hausa patients. There was a seasonal peak in July, and the incidence was about one per cent of deliveries. The risk increased with both age and parity. Symptoms began most commonly in the second week after delivery, and admission was commonest in the fourth. Typical signs of cardiac failure were found, and pulsus alternans, atrio-ventricular valvular incompetence, transient systemic hypertension and splenomegaly were common. The chest radiograph showed marked cardiomegaly, and extrasystoles and inverted T waves were often present in the electrocardiogram (ECG). Hypoalbuminaemia was common. Digoxin and diuretics were rapidly effective, causing a mean weight loss of 29 per cent in 15 days, resolution of hypertension, and a fall in the cardio-thoracic ratio (CTR) from 61 to 53 per cent. During the first year after diagnosis, the CTR became normal in 82 per cent of patients, and the ECG in 60 per cent. PPCF recurred, again with the same seasonal variation, after 19 per cent of subsequent pregnancies. During follow up for two to five years, 22 per cent of the women became hypertensive, and 11 per cent died. The prognosis was worst in those with an arrhythmia, hypertension, sustained cardiomegaly or aged 30 or more. Asymtomatic post-partum hypertension (PPHT) was found in 61 per cent of normal Hausa women, with a seasonal peak in May, especially in those with hypertension during pregnancy or labour, and twin pregnancies. Peri-partum cardiac failure may be due to the combined pressure load of PPHT, the volume load from eating the customary sodium-rich kanwa, and the cardiovascular demands of heat, both climatic and traditionally self-imposed.
Collapse
|
26
|
Abstract
A single oral dose of 5 mg of bromocriptine significantly lowered the TSH response to 200 microgram TRH intravenously in eight healthy men compared with control experiments in the same subjects. This finding may be relevant in chronic bromocriptine therapy.
Collapse
|
27
|
|
28
|
Hypothalmic-pituitary adrenal responsiveness to dexamethasone-insulin tolerance test in acromegalic patients before and during treatment with bromocriptine. ACTA ENDOCRINOLOGICA 1978; 88:18-22. [PMID: 580533 DOI: 10.1530/acta.0.0880018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Insulin tolerance tests were carried out in 10 acromegalic patients after 1 mg dexamethasone had been given the previous evening (DEX-ITT). Nine patients showed a rise in plasma 11-OHCS and four patients showed a rise in plasma growth hormone (GH) levels. These responses were unaltered after treatment with bromocriptine 10 mg daily for two months. Basal plasma GH levels fell in 6 of the patients and the mean plasma GH levels of the 10 patients during an oral glucose tolerance test (OGTT) fell from 63.2 +/- 25.5 ng/ml before treatment to 53.0 +/- 27.1 ng/ml (mean +/- sem; p less than 0.05). These data fail to confirm a previous report of abnormal hypothalmic-pituitary-adrenal suppressibility during a DEX-ITT in acromegalic patients. They also indicate that bromcriptine does not alter the responses of plasma 11-OHCS and plasma GH to the DEX-ITT despite lowering plasma GH levels.
Collapse
|
29
|
|
30
|
Abstract
The number of patients with cardiac failure admitted to hospital in Zaria, Nigeria, month by month during 1972-75 differed highly significantly between the cooler dry months and the hot wet months. The reasons are uncertain, but seasonal changes in blood-pressure and the effects of heat on the circulation and of humidity on the efficiency of sweating may be responsible.
Collapse
|
31
|
Glibenclamide and syndrome of inappropriate secretion of antidiuretic hormone. BRITISH MEDICAL JOURNAL 1977; 1:1137. [PMID: 405069 PMCID: PMC1606687 DOI: 10.1136/bmj.1.6069.1137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
32
|
Abstract
The acute hypoglycaemic reaction is accompanied by a rise in systolic and a slight fall in diastolic blood pressure and a tachycardia. In contrast, during beta-blockade with propranolol there is a rise of both systolic and diastolic blood pressures and bradycardia. Restoration of blood glucose to normal is delayed. With metoprolol there is a lesser increase in diastolic blood pressure and a slight tachycardia. Restoration of the blood glucose to normal is little delayed. When patients liable to hypoglycaemia require a beta-blocking agent, it is suggested that a selective blocker such as metoprolol should be used.
Collapse
|
33
|
Inhibition of antibody-dependent cell-mediated cytotoxicity (ADCC) as a means of detection of immune complexes in the sera of patients with thyroid disorders and bronchogenic carcinoma. Clin Exp Immunol 1976; 25:270-9. [PMID: 986262 PMCID: PMC1541344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Circulating immune complexes in the sera of patients with thyroid disorders or bronchogenic carcinoma were investigated using an assay system based on the inhibition of the ADCC activity of rat spleen cells. Increased inhibition, as compared with that of the sera of age and sex matched controls, was found in patients with thashimoto thyroiditis, primary hypothyroidism and bronchogenic carcinoma. The degree of inhibition in the first two groups was markedly increased compared with control sera of the same IgG content. However, the results in the lung cancer group were slightly but not significantly greater than in controls with the same level of IgG. Increased IgG levels were found in patients with thashimoto thyroiditis and thyrotoxicosis, and also in patients with bronchogenic carcinoma who had mediastinal gland involvement. The lower level of sensitivity of the assay system was approximately 600 ng added aggregated IgG, corresponding to a concentration of 6mu g/ml in the sample assayed. It is possible that circulating immune complexes may exist in lung cancer, but at a level below that of the present assay system.
Collapse
|
34
|
T, B and K cells in autoimmune thyroid disease. Clin Exp Immunol 1976; 25:17-22. [PMID: 1086749 PMCID: PMC1541376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The K-cell cytotoxic activity of peripheral blood lymphoid cells from 104 patients with autoimmune thyroid disease and from age and sex matched control subjects was measured using chicken erythrocytes as target cells. Patients with Hashimoto thyroiditis,primary hypothyroidism and thyrotoxicosis who were either newly diagnosed and untreated or had received therapy for less than or equal to 1 year showed a significant increase in K-cell cytotoxic activity. Patients who had received treatment for greater than 1 year and less than or equal to 5 years showed no such comparable increase in cytotoxic activity. Within the group of patients with untreated thyrotoxicosis it was found that K-cell cytotoxic activity was related to both goitre size and serum antibody titre. Thus patients with little or no goitre showed a highly significant elevation of cytotoxic activity whereas patients with moderate to large goitres gave values within the normal range. Similarly patients with no detectable serum thyroid autoantibodies showed high K-cell activity while patients with positive antibody titres did not. It was also shown that neither the absolute number nor the proportion of circulating T and B lymphocytes in patients with autoimmune thyroid disease as assessed by the sheep red cell rosette method and by indirect immunofluorescence was significantly different from that observed in the normal control population. No correlation was found between peripheral blood K-cell cytotoxic activity and the percentage of circulating null cells, i.e. 100-(percentage T + percentage B) in either patients or control subjects.
Collapse
|
35
|
Bites by the night adder (Causus maculatus) and burrowing vipers (genus Atractaspis) in Nigeria. Am J Trop Med Hyg 1976; 25:517-24. [PMID: 945703 DOI: 10.4269/ajtmh.1976.25.517] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Nineteen patients proven to have been bitten by the small African adders Causus maculatus, Atractapis dahomeyensis and A. microlepidota were studied in the Nigerian savanna region. One of the patients bitten by C. maculatus was drowsy, hypotensive and flaccid on admission but recovered without treatment. Mild or moderate local swelling, local lymphadenitis and mild fever were the only other features in this group. None of the patients bitten by Atractaspis had signs of systemic envenoming apart from moderate fever. Local blistering appeared in two cases but did not progress to necrosis. No patient showed any disturbance of blood coagulation, or evidence of spontaneous hemorrhage or of cranial nerve lesions. The small literature on the effects of Causus and Atractaspis venoms in man and in laboratory animals is reviewed. It appears that bites by these species are very unlikely to cause serious ill effects. A few deaths from Atractaspis bites have been reported, but the danger from these species has been exaggerated.
Collapse
|
36
|
Abstract
Six patients with proved rabies were studied with a combination of clinical, physiologic and pathologic technics. Three were given a type of intensive care but died with evidence of respiratory failure. Although circulatory failure did not develop in any of the six patients, three had supraventricular arrhythmias: interstitial myocarditis was found in one of these and rabies virus was isolated from the myocardium of another. Inspiratory muscle spasm was the dominant clinical feature in all cases. This occurred as part of the hydrophobic response and followed stimulation of the upper respiratory tract and skin. Hydrophobia may represent an exaggerated respiratory tract irritant reflex with associated arousal. Later in the course of the disease, various patterns of periodic and ataxic breathing were observed. Widespread brain stem encephalitis was discovered at autopsy, with particular involvement of the neighborhood of the nucleus ambiguous in two of three patients examined. In one patient cerebral metabolism was grossly abnormal, with greatly reduced cerebral oxygen consumption suggesting irreversible brain damage. Respiratory and circulatory disturbances may well be immediate causes of death in patients with rabies, but the present studies reemphasize the severity of the encephalitis which remains the ultimate barrier to survival. In the developing countries in which rabies is still a major problem and in which the cost precludes intensive care, the clinical management of rabies can aim only to reduce suffering by heavy sedation.
Collapse
|
37
|
Necrosis, haemorrhage and complement depletion following bites by the spitting cobra (Naja nigricollis). THE QUARTERLY JOURNAL OF MEDICINE 1976; 45:1-22. [PMID: 943796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The Spitting Cobra, Naja nigricollis, is widely and densely distributed in Africa. Fourteen patients with proven N. nigricollis bites, who were seen in the savanna region of Nigeria, did not exhibit the neurological signs, such as cranial nerve lesions and respiratory paralysis, expected following Elapid poisoning. All had local swelling, in eight cases involving the entire limb, and ten developed local tissue necrosis. Spontaneous haemorrhage was detected in three cases and was the probable cause of death in one of them; the other death in this series was unexplained. Haematological abnormalities included prolonged clot lysis anf failure of clot retraction due to a platelet defect. There was no specific deficit in clotting factors and a delayed rise in fibrin degradation products was attributed to extensive tissue damage at the site of the bit. Most patients showed depletion of complement component C3 and glycine-rich beta-glycoprotein (GBG), suggesting activation of the alternative pathway of complement fixation. There was evidence of hepatocellular damage in two out of six patients investigated. There was no evidence that specific polyvalent antivenoms, used in doses of up to 80 ml, prevented any of the effects of N. nigricollis venom. Clinical laboratory diagnosis is discussed. In the past many bites were wrongly classified as viper bites on the basis of clinical findings. Immunodiagnosis is a promising method for assessing the true importance of N. nigricollis bite in West Africa.
Collapse
|
38
|
Bites by puff-adder (Bitis arietans) in Nigeria, and value of antivenom. BRITISH MEDICAL JOURNAL 1975; 4:697-700. [PMID: 1203728 PMCID: PMC1675831 DOI: 10.1136/bmj.4.5998.697] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ten patients bitten by the puff-adder (Bitis arietans) were studied in the North of Nigeria. Six showed severe local signs, and four also had evidence of systemic envenoming, including spontaneous bleeding with thrombocytopenia, hypotension, and bradycardia. Two patients died after developing circulatory collapse and renal failure. Antivenom and intravenous fluid restored blood pressure in two hypotensive patients, and antivenom probably prevented the development of local necrosis in four others with massive local swelling. Victims of B arietans who have swelling of more than half the bitten limb or show signs of systemic envenoming should be given at least 80 ml of specific polyvalent antivenom and watched carefully for signs of circulatory collapse. Debridement of necrotic tissue may be necessary.
Collapse
|
39
|
Proceedings: Postpartum hypertension and aetiology of peripartum cardiac failure. Heart 1975; 37:784. [PMID: 1156502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
40
|
Defaulters from follow-up after pre-partum cardiac failure. TROPICAL AND GEOGRAPHICAL MEDICINE 1975; 27:109-14. [PMID: 1169831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The problem of default from follow-up prejudices the study of disease in Africa. During studies of 224 patients with pre-partum cardiac failure were found that 119 had defaulted from follow-up for six months or more, after an average period of 22 months from their admission. A sociologist tried to find all these patients at home and interviewed those who were found. If the patient was not found, information was sought from the village head and from friends and relatives. Thirteen patients had died. The 69 who were traced gave a total of 101 reasons for default. Domestic reasons prodominated, of which poverty, moving home and the difficulties of travel were the most important. Among personal reasons, feeling well was the commonest single reason, and was given by 19 patients. The results show that the problems of a subsistence agricultural economy dominate the reasons for default, and that such problem cannot be overcome without changes in society. Our findings are relevant in the care of all chronic diseases and throughout rural Africa.
Collapse
|
41
|
Abstract
In three cases of human rabies, in which the diagnosis was proved postmortem, rabies antigen was detected by direct immunofluorescence of frozen sections of facial skin. The antigen was thought to be in nerve fibers in association with hair follicles. Development of this technique might enable the establishment of a method for the diagnosis of human rabies during life.
Collapse
|
42
|
Abstract
Management of a patient with snake bite is influenced by the nature of the offending snake. Species diagnosis based on the patient's history and physical signs is often unreliable and the possibility of making a species diagnosis by immunological means has therefore been investigated. Wound aspirates, blister fluids, sera, and urine samples from patients with snake bite were examined for the presence of species-specific venoms using immunodiffusion. A positive species diagnosis was made in 40 out of 101 patients. Immunodiagnosis was especially successful in patients bitten by the puff adder, Bitis arietans, and the African spitting cobra, Naja nigricollis. A higher success rate could probably be achieved using more specific antisera and more sensitive assay techniques.
Collapse
|
43
|
Bites by the saw-scaled or carpet viper (Echis carinatus): trial of two specific antivenoms. BRITISH MEDICAL JOURNAL 1974; 4:437-40. [PMID: 4154124 PMCID: PMC1612524 DOI: 10.1136/bmj.4.5942.437] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Echis carinatus is the most important cause of morbidity and mortality from snake bite in Nigeria and in many other parts of the world. Forty-six patients with systemic poisoning by this snake were given echis antivenom made either by the South African Institute for Medical Research (S.A.I.M.R.) or by Behringwerke (North and West African polyvalent antivenom). A simple test of blood coagulability was used to assess whether an adequate neutralizing dose of antivenom had been given. An average of 15.2 ml S.A.I.M.R. antivenom restored normal coagulability permanently in all 23 patients in one group, but in the other group receiving an average dose of 37.9 ml Behringwerke antivenom normal clotting resulted in only 18 out of 23 patients. Local tissue swelling was similar in both groups, but local necrosis occurred in three patients treated with Behringwerke antivenom and in none given S.A.I.M.R. antivenom.
Collapse
|
44
|
|
45
|
Perpartum cardiac failure. An explanation for the observed geographic distribution in Nigeria. Bull World Health Organ 1974; 51:203-8. [PMID: 4549486 PMCID: PMC2366230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Peripartum cardiac failure (PPCF) is common in Zaria, in northern Nigeria, but has not been described elsewhere in Nigeria except in Ibadan. The geographic origin of a series of 224 patients with PPCF was studied in Zaria, and a survey of the syndrome as seen in hospitals and by physicians in the northern states of Nigeria was carried out; information was also gathered from medical and nursing students from various tribal groups in the same area. It was found that PPCF is only common in the areas of Hausa majority, mostly around Zaria and Malumfashi, where the postpartum practices of taking hot baths, lying on a hot bed, and taking large amounts of kanwa (a lake-salt rich in sodium) are pursued with great vigour. These customs may impose a critical load on a vulnerable myocardium, and it seems that tribe and tradition could well explain the high incidence of PPCF around Zaria.
Collapse
|
46
|
|
47
|
Trial of chloramphenicol for meningitis in northern savanna of Africa. BRITISH MEDICAL JOURNAL 1973; 3:379-81. [PMID: 4199744 PMCID: PMC1586699 DOI: 10.1136/bmj.3.5876.379] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In a controlled trial chloramphenicol proved as effective and much cheaper than penicillin for the treatment of group A meningococcal meningitis in Zaria, Nigeria. A short course of five days cured most patients. Adults and older children were soon able to take chloramphenicol by mouth, which reduced the cost and simplified treatment.It is suggested that chloramphenicol is a suitable alternative to sulphonamides for the treatment of meningococcal meningitis in those parts of Africa where the organism is sulphonamide-resistant.
Collapse
|
48
|
|
49
|
Hyperparathyroidism and the delineation of adenomas by scanning. Proc R Soc Med 1969; 62:39. [PMID: 5763464 PMCID: PMC2279024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
50
|
Investigations on male hypogonadism. Proc R Soc Med 1969; 62:27-31. [PMID: 5763461 PMCID: PMC2279059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|