Stirrer tank: an appropriate technology to immobilize the CB.Hep-1 monoclonal antibody for immunoaffinity purification

The CB.Hep-1 monoclonal antibody was coupled to CNBr-activated Sepharose CL 4B at three different immobilization scales for purification of recombinant hepatitis B surface antigen. Standard laboratory apparatus to obtain immunosorbents of 1 l (scale I) and 3 l (scale II) as well as a stirrer tank to prepare 6 l immunosorbents (scale III) were used. The binding capacity at scale III was 2- and 1.5-fold higher with respect to the scales II and I, while a reduction in the ligand leakage of 5- and 2-folds was observed. Immunosorbents from scale II showed a significantly reduced adsorption, and an increased ligand leakage. Differences in the coupling efficiency were not observed. Antigen purity eluted from the immunosorbents was always above 85%.

Synthesis and antiparasitic activity of 2-(trifluoromethyl)-benzimidazole derivatives

2-(Trifluoromethyl)benzimidazole derivatives substituted at the 1-, 5-, and 6-positions have been synthesized and in vitro tested against the protozoa Giardia lamblia, Entamnoeha histolytica. and the helminth Trichinella spiralis. Results indicate that all the compounds tested are more active as antiprotozoal agents than Albendazole and Metronidazole. One compound (20) was as active as Albendazole against T. spiralis. These compounds were also tested for their effect on tubulin polymerization and none inhibited tubulin polymerization.

Porphyria cutanea tarda affecting lower lip

In porphyria cutanea tarda, the most common type of porphyria, blisters of the skin occur because of high sensitivity to sunlight. This case report describes porphyria cutanea tarda of the lower lip mimicking an actinic cheilitis in a 62-year-old man with a history of Hodgkin's lymphoma.

Crystallographic studies of the interaction between the ferredoxin-NADP+ reductase and ferredoxin from the cyanobacterium Anabaena: looking for the elusive ferredoxin molecule

Ferredoxin-NADP(+) reductase (FNR) and its physiological electron donor ferredoxin (Fd) from the cyanobacterium Anabaena PCC7119 have been co-crystallized. The unit-cell parameters are a = b = 63.72, c = 158.02 A and the space group is P2(1)2(1)2(1). The crystal structure has been solved with 2.4 A resolution synchrotron data by molecular replacement, anomalous dispersion and R(min) search methods. For the computations, the crystal was treated as a merohedral twin. The asymmetric unit contains two FNR molecules and one ferredoxin molecule. The packing of the FNR molecules displays a nearly tetragonal symmetry (space group P4(3)2(1)2), whereas the ferredoxin arrangement is orthorhombic. This study provides the first crystallographic model of a dissociable complex between FNR and Fd.

A redox-dependent interaction between two electron-transfer partners involved in photosynthesis

Ferredoxin:NADP+:reductase (FNR) catalyzes one terminal step of the conversion of light energy into chemical energy during photosynthesis. FNR uses two high energy electrons photoproduced by photosystem I (PSI) and conveyed, one by one, by a ferredoxin (Fd), to reduce NADP+ to NADPH. The reducing power of NADPH is finally involved in carbon assimilation. The interaction between oxidized FNR and Fd was studied by crystallography at 2.4 A resolution leading to a three-dimensional picture of an Fd-FNR biologically relevant complex. This complex suggests that FNR and Fd specifically interact prior to each electron transfer and disassemble upon a redox-linked conformational change of the Fd.

[Incomplete sagittal septum of the bladder]

OBJECTIVE

To describe an additional case of incomplete sagittal septum of the bladder.

METHODS

A case of incomplete sagittal septum of the bladder in a young, asymptomatic patient with paralysis of both lower limbs is presented and literature is briefly reviewed.

RESULTS

The diagnosis was made by intravenous urography performed five years after the accident that had caused the paralysis. Radiological evaluation showed an "apple heart" bladder with reduced capacity. No treatment was required.

CONCLUSIONS

Incomplete sagittal septum of the bladder is rare. To our knowledge, only 7 cases have been previously reported. Incomplete sagittal septum is like complete septum, but both cavities communicate anteriorly or distally, according to the direction and depth the septum protrudes into the bladder.

Quality indicators in ambulatory surgery. A prospective study

Introduction: Ambulatory Surgery has emerged and developed in Spain in a similar way as in other occidental countries. Once established as a model for surgical care, results must be improved using objective quality indicators to assure minimal morbidity, efficient use of resources and satisfaction of patients and family. Objective: To provide a list of quality assessment indicators in Ambulatory Surgery and to discuss the necessity of obtaining a general consensus regarding the complexity of both the operations and the patients undergoing surgery. Design: Prospective and descriptive study. Patients and Methods: The study was performed on 833 ambulatory patients operated on in the Ambulatory Surgical Unit of the Can Misses Hospital of Ibiza. Surgical specialities involved were General Surgery, Ophthalmology, Orthopaedics, Urology, Gynaecology, and E.N.T. All diagnoses and proceedings were classified according to the CIE-9 and DGR systems, showing as an example the codes related to the General Surgery department. Quality Indicators evaluated were: (a) unplanned admission index; (b) re-admission index; (c) emergency department consultations; (d) cancellation index; (e) substitution index; and (f) postoperative pain evaluation. Results: Specialities involved were: Ophthalmology 277 patients (33.2%), General Surgery 189 (22.8%), Orthopaedics 142 (17%), Urology 90 (10.8%), E.N.T. 79 (9.5%) and Gynaecology 56 (6.7%). Unplanned Admission Index was 7.2%; Re-Admission Index 0.4%; Emergency department consultation 1.6%; Cancellation Index 3.3% and Substitution Index 70%. The reasons for unplanned admission were due to specific complications in 36 cases (60.1%), followed by those secondary to an inadequate selection of the patient in 22 cases (36.6%). Conclusions: It is necessary to apply a series of Quality Indicators in Ambulatory Surgery. Their systematic evaluation may help us define national standards in order to continuously improve our results.

Refined X-ray structures of the oxidized, at 1.3 A, and reduced, at 1.17 A, [2Fe-2S] ferredoxin from the cyanobacterium Anabaena PCC7119 show redox-linked conformational changes

The chemical sequence of the [2Fe-2S] ferredoxin from the cyanobacterium AnabaenaPCC7119 (Fd7119) and its high-resolution X-ray structures in the oxidized and reduced states have been determined. The Fd7119 sequence is identical to that of the ferredoxin from the PCC7120 strain (Fd7120). X-ray diffraction data were collected at 100 K with an oxidized trigonal Fd7119 crystal, at 1.3 A resolution, and with an orthorhombic crystal, previously reduced with dithionite and flash frozen under anaerobic conditions, at 1.17 A resolution. The two molecular models were determined by molecular replacement with the [2Fe-2S] ferredoxin from the strain PCC7120 (Rypniewski, W. R., Breiter, D. R., Benning, M. M., Wesenberg, G., Oh, B.-H., Markley, J. L., Rayment, I., and Holden, H. M. (1991) Biochemistry 30, 4126-4131.) The final R-factors are 0. 140 (for the reduced crystal) and 0.138 (for the oxidized crystal). The [2Fe-2S] cluster appears as a significantly distorted lozenge in the reduced and oxidized redox states. The major conformational difference between the two redox forms concerns the peptide bond linking Cys46 and Ser47 which points its carbonyl oxygen away from the [2Fe-2S] cluster ("CO out") in the reduced molecule and toward it ("CO in") in the oxidized one. The "CO out" conformation could be the signature of the reduction of the iron atom Fe1, which is close to the molecular surface. Superposition of the three crystallographically independent molecules shows that the putative recognition site with the physiological partner (FNR) involves charged, hydrophobic residues and invariant water molecules.

[The search for clinical markers of abnormal hypercoagulable states among factors that trigger venous thromboembolic disease]

We proposed to search for markers of hypercoagulable states in function of age, sex or factors that trigger venous thromboembolic disease (VTD) in a group of patients so diagnosed. The following patient data were analyzed: age, sex and triggering factors of VTD categorized as associative-transient, permanent or unknown. In patients under age 55 years of age in whom the triggering factor of VTD was unknown, and in those who had a family and/or personal history of VTD, coagulability was assessed approximately three months after the episode of acute thrombosis and was repeated during follow-up. From April 1993 to July 1996 we saw 297 patients diagnosed of VTD and performed 187 coagulability tests (63%). Eighty-six were normal (46%) and 101 (54%) abnormal. No significant relations were found for age, sex or triggering factors and the results of follow-up coagulability testing. We conclude that factors known to trigger VTD are not the only ones relevant for indicating the need to order the assessment of coagulability, given that the presence of coagulopathy is not confined to patients with supposed clinical markers.

Microcomputer decision support system for intensive care

This article describes a computer system to support decisions in Intensive Medicine developed for a multipurpose Intensive Care Unit (13 beds and about 700 yearly patients). The system is used in a microcomputer (486DX4). Works done in this area are mentioned; and the different programs which integrate the system, the advantages of its use and the results accomplished are described. Some of the most important results are the quality increment of the medical care given, physicians' possibilities of dedicating more time to their patients, cost reductions, and improvements in the development of teaching and in the conditions to carry out research work in the Intensive Care Unit (ICU). An analysis is made of the system requirements that guarantee its integration to the Unit work, and the easy and safe use of it by the physicians and nurses.

Medicinal and veterinary plants of El Caurel (Galicia, northwest Spain)

A study of the medicinal and veterinary plants popularly used in El Caurel region (Lugo province, northwest Spain) and their relationships is reported. We obtained data for 85 species belonging to 31 families of vascular plants. Their vernacular names, properties, preparations, mode and popular uses are presented.

Role of thyroid hormone in regulation of renal phosphate transport in young and aged rats

In the present study, we have examined the cellular mechanisms mediating the regulation of renal proximal tubular sodium-coupled inorganic phosphate (Na/Pi) transport by thyroid hormone (T3) in young and aged rats. Young hypothyroid rats showed a marked decrease in Na/Pi cotransport activity, which was associated with parallel decreases in type II Na/Pi cotransporter (NaPi-2) protein and messenger RNA (mRNA) abundance. In contrast, administration of long-term physiological and supraphysiological doses of T3 resulted in significant increases in Na/Pi cotransport activity, protein, and mRNA levels. Nuclear run-on experiments indicated that thyroid hormone regulates NaPi-2 mRNA levels by a transcriptional mechanism. In aged rats, although there were no changes in T3 serum levels (when compared with young animals), there were significant decreases in serum Pi concentration, renal Na/Pi cotransport activity, and NaPi-2 protein and mRNA abundance. These effects were mediated, at least in part, by a reduction in the transcriptional rate of the NaPi-2 gene, probably caused by, among other factors, a smaller response to the stimulatory action of T3. Compared with young rats, the old rats exhibited less sensitivity of the Na/Pi cotransporter to thyroid hormone, with-decreased effects in both hypothyroid (inhibitory) and hyperthyroid (stimulatory) animals.

An encyclopedia of mouse genes

The laboratory mouse is the premier model system for studies of mammalian development due to the powerful classical genetic analysis possible (see also the Jackson Laboratory web site, http://www.jax.org/) and the ever-expanding collection of molecular tools. To enhance the utility of the mouse system, we initiated a program to generate a large database of expressed sequence tags (ESTs) that can provide rapid access to genes. Of particular significance was the possibility that cDNA libraries could be prepared from very early stages of development, a situation unrealized in human EST projects. We report here the development of a comprehensive database of ESTs for the mouse. The project, initiated in March 1996, has focused on 5' end sequences from directionally cloned, oligo-dT primed cDNA libraries. As of 23 October 1998, 352,040 sequences had been generated, annotated and deposited in dbEST, where they comprised 93% of the total ESTs available for mouse. EST data are versatile and have been applied to gene identification, comparative sequence analysis, comparative gene mapping and candidate disease gene identification, genome sequence annotation, microarray development and the development of gene-based map resources.

HCV genotypes in Northern Italy: a survey of 1368 histologically proven chronic hepatitis C patients

BACKGROUND/AIMS

Hepatitis C virus (HCV) easily undergoes genomic changes, thus accounting for the presence of different genotypes, with different geographic distributions and different outcomes of chronic hepatitis. Type 1b is frequently found in advanced diseases; however, since this genotype is the most prevalent in older patients, the association with advanced age and severity of the disease is confounding. The aim of this study was to assess changes in the prevalence of HCV genotypes by surveying a large population of chronic hepatitis C patients in Northern Italy, and to assess if the high prevalence of genotype 1b in older patients with advanced diseases simply reflects the duration of HCV infection, rather than intrinsic biological properties of HCV.

METHODS

We studied 1368 HCV-RNA positive patients, with histologically proven chronic hepatitis. Drug addiction, blood transfusions and sporadically acquired infections represented the risk factors.

RESULTS

Genotype 1b, the most prevalent isolate, and genotype 2a were associated with older age, cirrhosis, sporadically-acquired infections and blood transfusion, while types 1a, 3a, and 4 were associated with younger age, chronic persistent hepatitis and drug addiction. Patients with a history of transfusions were divided into four groups depending on the period of transfusion. The prevalence of genotype 1b decreased with time. Type 3a appeared only after 1979.

CONCLUSION

The severity of chronic hepatitis C could be related more to the duration of the infection rather than to the intrinsic pathogenicity of HCV genotypes.

The interaction of phospholipase A2 with liposomes: an immunological approach to its study

Porcine pancreatic phospholipase A2 (PLA2) has been incubated for 2 hours at 34 degrees C with rabbit anti-pig pancreatic PLA2 polyclonal antiserum in the absence or presence of phosphatidylcholine liposomes in different physical states. Subsequent assay of hydrolysis -triggered through addition of 5 mM Ca2+- at 34 degrees C, shows that preincubation with antiserum in the presence of 1,2-dimyristoyl-3-sn-phosphatidylcholine liquid-crystalline vesicles, renders the PLA2 activity undetectable, similarly to what is found if preincubation is carried out in the absence of liposomes. In contrast, 1,2-dipalmitoyl-3-sn-phosphatidylcholine liposomes, which at 34 degrees C are in the gel-phase, protect the enzyme from the antiserum effect. The results are consistent with a stronger binding of PLA2 to gel phase, as compared to liquid crystalline vesicles and suggest that through the physical interaction with liposomes in the gel state, the enzyme is shielded from reaction with the antibodies. Taking into account the characteristic hydrolysis profiles of vesicles in different physical states, it can be concluded that the above interpretation agrees with the proposal that PLA2-membrane association promotes the interfacial activation of the enzyme.

Interferon alfa treatment of HCV RNA carriers with persistently normal transaminase levels: a pilot randomized controlled study

Most patients with serum hepatitis C virus (HCV) RNA and persistently normal alanine transaminase (ALT) levels show histological features of mild to moderately active chronic hepatitis. Some cirrhosis has also been reported. To assess whether interferon (IFN) treatment led to long-term HCV suppression in these patients, 31 previously untreated patients (15 men, 16 women; mean age, 44 years) with serum HCV RNA, persistently normal ALT levels on at least four consecutive occasions 2 months apart, and histological features of chronic hepatitis (21 mild activity, 10 moderate activity) were randomized to receive 1FN-alpha-2a, 3 MU three times a week for 6 months (n = 16), or no treatment (n = 15). All patients were followed up for at least 6 months after treatment ended. HCV RNA was tested by nested reverse-transcription polymerase chain reaction (RT-PCR) using 5'-untranslated region complementary primers, quantified by branched-DNA assay, and typed by nested RT-PCR testing for the HCV core region. Treated and untreated patients had similar epidemiological, virological, and histological characteristics. At the end of treatment, serum HCV RNA was still detected in 15 patients (94%) and 14 controls (93%). ALT levels flared up in 10 patients receiving IFN (62%) and in 1 control (62% vs. 7%; P < .005, chi2 test). In conclusion, 6 months' treatment with IFN-alpha-2a did not eradicate HCV RNA from serum in carriers with persistently normal ALT levels but caused ALT flare-ups in two thirds of them. Until more is known about the natural history of HCV RNA carriers with normal ALT levels, these patients should not be treated with IFN.

Reciprocal interaction between glutamate and dopamine in the pars reticulata of the rat substantia nigra: a microdialysis study

We studied the interactions between glutamate and dopamine in the pars reticulata of the substantia nigra by using microdialysis in unanaesthetized rats. Increased extracellular levels of glutamate in the pars reticulata were obtained by microinjecting the muscarinic agonist carbachol into the ipsilateral subthalamic nucleus. The increase of glutamate levels was followed by increments in extracellular levels of dopamine and GABA. Increased levels of the three neurotransmitters were also observed during the administration of N-methyl-D-aspartate through the microdialysis probe. The increase in glutamate and GABA caused by N-methyl-D-aspartate was blocked by SCH 23390, a selective D1 antagonist. However, the D1 antagonist did not prevent the increase in dopamine levels. The selective D1 agonist SKF 38393, added to the microdialysis probe, increased the levels of the three neurotransmitters. However, after the lesion of the subthalamic nucleus with kainic acid, SKF 38393 increased only the level of GABA but not those of glutamate and dopamine. In addition, the lesion of the subthalamic nucleus produced a drastic (80%) fall in the extracellular levels of glutamate. These data suggest that glutamate, through N-methyl-d-aspartate receptors, stimulates the release of dopamine from dopaminergic dendrites present in the substantia nigra pars reticulata, and that dopamine in turn stimulates the release of glutamate and GABA. Both effects are mediated by D1 dopamine receptors present on subthalamonigral and striatonigral axon terminals, respectively.

Epidemiology and control of egg-associated Salmonella enteritidis in the United States of America

The isolation rate for Salmonella enterica serotype Enteritidis (SE) in humans in the United States of America (USA) increased from 1,207 sporadic isolates identified in 1976 (0.6 isolates/100,000 population) to 10,201 identified in 1995 (4.0/100,000 population). The proportion of reported Salmonella isolates which were SE increased from 5% to 25% during the same time period. In 1990, 1994, and 1995, SE was the most commonly reported reported Salmonella serotype in the USA. Much of this increase has been associated with the consumption of contaminated shell eggs. An examination of the results of a United States Department of Agriculture (USDA) survey of spent hens at slaughter and unpasteurised liquid egg at breaker plants (liquid egg processors) in 1991 and 1995 reveals an increase in the prevalence of SE isolates overall and in most regions of the USA. SE phage type 4 (pt 4), the predominant SE phage type in other parts of the world, has emerged in the egg industry in the western USA concurrent with a sharp increase in the number of sporadic human SE pt 4 isolates in California and Utah. Research on the molecular structure and virulence of SE pt 4 isolates from the USA as compared with isolates from other parts of the world (human and poultry) should be a priority. A comparison of DNA from pt 4 isolates from the USA and Europe may provide information about the potential threat to public health and poultry in the USA from this phage type. Some regional success in the reduction of human illness as a result of SE control efforts is apparent. The Pennsylvania Egg Quality Assurance Program has shown progress in reducing SE infection in participating flocks. At a national level, however, neither the incidence of human illness due to SE nor the prevalence of SE in flocks and unpasteurised liquid eggs have decreased significantly, despite the implementation of the USDA 'trace back' regulation from 1990 to 1995, and intensified efforts to educate food handlers and to enforce safe food handling practices. More effort is needed to control SE at every stage of the egg continuum, from production through to consumption. A risk-reduction approach, with barriers to the introduction and multiplication of the pathogen throughout the farm-to-table continuum, is the most practical method for reducing human illness from SE in shell eggs at present. An effective long-term solution will require interdisciplinary efforts involving government, industry, consumers, and academics. Interventions should be developed and evaluated in compliance with the potential for reducing the risk to human health and cost-effectiveness.

[A non-invasive test choice for the diagnosis of coronary disease in women]

BACKGROUND AND PURPOSE

Regarding coronary heart disease, women have often been excluded from clinical trials. Current practical recommendations are thus based on studies in men. To identify the non invasive technique of choice in detecting coronary artery disease in women, a study with different diagnostic tests has been undertaken.

METHODS

Exercise stress test, dipyridamole echocardiography (0.84 mg/kg), dobutamine echocardiography (up to a total dose of 40 micrograms/kg per minute and atropine if necessary), MIBI-SPECT during dobutamine infusion and coronary angiography, were performed in 40 consecutive women with chest pain and no previous history of coronary artery disease.

RESULTS

The four tests had similar sensitivity: exercise stress test (80%; CI 95%, 52-94), dipyridamole echocardiography (80%; CI 95%, 56-93), dobutamine echocardiography (80%; CI 95%, 56-93) and scintigraphy MIBI-SPECT (85%; CI 95%, 61-95). The specificity of dipyridamole echocardiography (100%; CI 95%, 83-100) and dobutamine echocardiography (90%; CI 95%, 67-98) was higher than that of exercise stress test (50%; CI 95%, 22-78) and MIBI-SPECT (65%; CI 95%, 41-84). The positive predictive values of dipyridamole and dobutamine echocardiography were 100% and 88% respectively.

CONCLUSIONS

The feasibility of exercise stress test in women is inferior to that of the other techniques. The sensitivity of the four tests to diagnose coronary artery disease is similar. The specificity of dipyridamole echocardiography and dobutamine echocardiography is higher than that of exercise stress test and MIBI-SPECT. Stress echocardiography can be considered the non invasive technique of choice for diagnosing coronary artery disease in women.

Interpretation of the TDx-FLM fluorescence polarization assay in pregnancies complicated by diabetes mellitus

The objective of this paper is to determine the applicability of the Abbott TDx-FLM fluorescence polarization assay in pregnancies complicated by diabetes mellitus. Retrospective review of records of women with pregnancies complicated by diabetes who underwent amniocentesis for fetal lung maturity using the Abbott TDx-FLM assay within 3 days of delivery was considered. Maternal diabetic control, neonatal birth weight, Apgar scores, umbilical cord gases, admissions to Neonatal Intensive Care Unit (NICU), development of respiratory distress syndrome (RDS) were evaluated. One hundred twenty-one patients with diabetes mellitus were identified. Thirteen (10.7%) had an FLM < or = 70 mg/g and 108 patients had > or = 70 mg/g. All obstetrical and diabetic variables were similar. RDS was not observed in neonates who had an FLM of > or = 70 mg/g. One neonate had RDS (FLM = 7.2 mg/g). The TDx-FLM > or = 70 mg/g may be interpreted as mature when obtained from transabdominal amniocentesis.

[Spontaneous rupture of renal angiomyolipoma]

OBJECTIVES

An additional case of spontaneous rupture of renal angiomyolipoma is described.

METHODS

The images and clinical data of the present case are presented.

RESULTS

A comparative analysis of the appropriate treatment described in the literature was performed.

CONCLUSIONS

If possible, conservative surgery should be attempted.

Growth enhancement in transgenic tilapia by ectopic expression of tilapia growth hormone

The generation of transgenic fish with the transfer of growth hormone (GH) genes has opened new possibilities for the manipulation of growth in economically important fish species. The tilapia growth hormone (tiGH) cDNA was linked to the human cytomegalovirus (CMV) enhancer-promoter and used to generate transgenic tilapia by microinjection into one-cell embryos. Five transgenic tilapia were obtained from 40 injected embryos. A transgenic animal containing one copy of the transgene per cell was selected to establish a transgenic line. The transgene was stably transmitted to F1 and F2 generations in a Mendelian fashion. Ectopic, low-level expression of tiGH was detected in gonad and muscle cells of F1 transgenic tilapia by immunohystochemical analysis of tissue sections. Nine-month-old transgenic F1 progeny were 82% larger than nontransgenic fish at p = .001. These results showed that low-level ectopic expression of tiGH resulted in a growth acceleration in transgenic tilapia. Tilapia GH gene transfer is an alternative for growth acceleration in tilapia.

Vacuum extraction of preterm infants with birth weights of 1,500-2,499 grams

This study evaluated neonatal morbidity in preterm infants with birth weights of 1,500-2,499 who were delivered by vacuum extraction. The retrospective, observational study covered 61 infants delivered vaginally with vacuum extraction versus 122 matched controls delivered spontaneously. All infants were at < 37 weeks of gestation, with birth weights ranging from 1,500 to 2,499 g. Main neonatal outcomes studied were Apgar scores, umbilical artery blood pH and base excess, intraventricular hemorrhage, admission to the neonatal intensive care unit and length of hospital stay. The study population did not differ in any maternal or neonatal demographic parameter. There was a decreased need for episiotomies in the vacuum-assisted deliveries versus the controls (41% versus 57%, P = .01, odds ratio = .51, confidence interval = .27, .96). Neonatal morbidity was not significantly different in infants with vacuum-assisted deliveries. Vacuum extraction does not seem to increase neonatal morbidity in preterm infants with birth weights of 1,500-2,499 g.

Dengue fever with thrombocytopenia: studies towards defining vulnerability of bleeding

PURPOSE

To define the period of greater vulnerability of bleeding in patients with Dengue fever in reference to the onset of their constitutional symptoms and the laboratory abnormalities.

PATIENTS AND METHODS

In a retrospective study we reviewed the records of all patients admitted to San Pablo Medical Center in 1991 with a diagnosis of Dengue Fever or Hemorrhagic Dengue. All patients with a platelet count of less than 125,000 were included for analysis. The exclusion criteria included the presence of systemic disorders which may influence the platelet count, and patients without documentation regarding the presence of constitutional symptoms suggestive of viral illness.

RESULTS

A total of 101 patients were analyzed of which only 74 were included in the study. All patients had fever and chills; skin rash, asthenia and general malaise was seen in over 50% of patients. Over 70% of patients had recovery of their platelet count, and most had their maximal thrombocytopenia within the 5th day and 8th day from the onset of constitutional symptoms. Leukopenia was seen in over 70% of patients with its lowest level within the 5th and 8th day from the onset of the constitutional symptoms. Significantly prolonged partial thromboplastin time was seen in 11% of the patients. Proteinuria was seen in 22% of the patients, 38% of which had it within the first 4 days of the onset of constitutional symptoms and also noted on the 5th and 6th day. Alteration in liver enzymes were noted in 47% of patients, with a maximal severity distributed in all time frames. Hypoalbuminemia was present in 28% of the patients, of these 67% presented within the first 4 days from the onset of constitutional symptoms. The pulse rate was usually normal in spite of the patient's dehydration and fever.

CONCLUSIONS

We identified three phases that define the sequence of events seen in the majority of patients with Dengue Fever and Thrombocytopenia. These are: 1. proteinuria and hypoalbuminemia; 2. maximal cytopenia; 3. bradycardia and liver enzyme elevation. We believe this information is useful in the management of patients with Dengue Fever and thrombocytopenia.

Skeletal development in newborn and weanling northern elephant seals

The neonatal period in the northern elephant seal (Mirounga angustirostris) differs markedly from that of most mammals. An intense 1-mo nursing period is followed by 2-3 mo during which seal pups consume neither food nor water. Because skeletal development in other species is rapid during this period, we determined the capability of elephant seals to continue skeletal growth under fasting conditions. We analyzed indirect markers of bone turnover [serum osteocalcin and alkaline phosphatase activity and urinary calcium and hydroxyproline (Hyp) excretion] in samples obtained sequentially from live pups throughout the fast. Serum osteocalcin was low at the beginning of the fast, peaked between 17 and 42 days, and then decreased to initial levels after 10 wk. Alkaline phosphatase activity increased linearly through 9 wk of fasting. Urinary calcium was relatively constant through 9 wk but decreased after 10 wk, whereas free and total Hyp decreased linearly. Clearance of 3H-labeled Hyp showed that virtually all (> 99%) free Hyp was oxidized and that only bound Hyp, for which there is no degradative mechanism, was excreted. Kinetics of 45Ca clearance, a direct measurement of mineral turnover, was virtually identical to that for young humans. Histomorphometry of ulnae obtained from pups which died of natural causes (usually trauma inflicted by adult males) indicated active surfaces (osteoid plus eroded) between 30 and 60% of total surface of highly porous bone containing < 60% bone area/tissue area. Thus all indicators of skeletal activity confirmed that young elephant seals continue skeletal development, notwithstanding the prolonged period during which they take in no food or water.

Positional distribution of octadecadienoic acids in sponge phosphatidylethanolamines

The distribution of C14-C22 fatty acids in the phosphatidylethanolamines isolated from the sponges Agelas sp. and Spongia tampa was investigated. Selective changes with phospholipase A2 (from Agkistrodon halys blomhoffii) followed by thin-layer chromatographic separation of the resulting lysophosphatidylethanolamines and free fatty acids and subsequent methylation with HCl/MeOH and diazomethane, respectively, revealed that the 5,9-octadecadienoic acid and the 9,12-octadecadienoic acid present showed no preference for either position sn-1 or sn-2 in these phosphatidylethanolamines. The other saturated and unsaturated fatty acids with chains between 14 and 22 carbons long were also found to be equally distributed between positions sn-1 and sn-2 in the phosphatidylethanolamines in these sponges. The results contrast with what is known about the distribution in most mammalian phospholipids, such as the phosphatidylcholines from human erythrocytes, where octadecadienoic acid typically occupies the sn-2 position.

[Synergism of midazolam and propofol in the induction of anesthesia]

INTRODUCTION

The purpose of this study was to determine the possible interaction of midazolam and propofol in the induction of anesthesia.

METHODS

A double-blind study of 90 ASA I-II women undergoing elective general surgery and gynecology was performed. The patients were divided into three groups of 30 patients receiving midazolam, propofol and a combination of both as the anesthesia induction agent. As a test of anesthetic induction the response to the verbal order of opening their eyes was evaluated. The dose-response curves for each group were determined by a logistic regression procedure while isobolographic analysis compared the actions of both agents separately and together.

RESULTS

The ED50 in the propofol group was 1.56 mg.kg-1 and that of the midazolam group was 0.24 mg.kg-1. In the midazolam-propofol group the ED50 of midazolam was reduced approximately a quarter (0.068 mg.kg-1) when associated to the half of the ED50 of propofol anteriorly obtained. Isobolographic analysis revealed that the conjunctive action of both drugs was synergic (p = 0.04).

CONCLUSIONS

Propofol potentiates the action of midazolam in anesthetic induction. Although this synergism also reduces with the association of thiopental-midazolam, the mechanism of action is not demonstrated as the same. Thiopental increases the affinity of the benzodiazepines for the GABA complex receptors which has not been described for propofol.

[Echocardiography with intravenous dipyridamole infusion in the assessment of ischemic cardiopathy. A comparison with the stress test]

BACKGROUND

Diagnosis of ischemic cardiomyopathy by noninvasive methods is a challenge for the clinician. Echocardiography with intravenous administration of dipyridamole has been proposed as an alternative to exercise stress test in this setting.

METHODS

Intravenous administration of dipyridamole (0.84 mg/kg in 6 minutes) with two-dimensional echocardiography and 12-lead electrocardiographic monitoring was performed in 50 patients. The test was considered positive when contractility of any of the left ventricular segments decreased, at least, one grade. In that moment, dipyridamole administration was stopped and aminophylline (40-240 mg over 1 to 3 minutes) was given. All patients underwent exercise stress test and coronary angiography.

RESULTS

Significant coronary artery disease (70% stenosis in, at least, one of the major vessels) was demonstrated in 32 patients. Twenty of these had a positive dipyridamole echocardiography test (62%) and 23 had a positive exercise stress test (71%). None of the patients without significant coronary artery disease had a positive dipyridamole echocardiography test and 5 patients (23%) has a positive exercise stress test. Dipyridamole echocardiography test had and overall sensitivity of 60% and a specificity of 100%. Exercise stress test had an overall sensitivity of 75% (NS) and a specificity of 67% (p less than 0.01). Dipyridamole echocardiography test was well tolerated: there were no complications during the test. One patient had a transitory type I second-degree AV block.

CONCLUSIONS

Dipyridamole echocardiography is a high specificity test for coronary artery disease and has a similar sensitivity than exercise stress test. It is well tolerated and in the authors' experience there were no complications.

An interesting case presentation: peripartum meningococcal meningitis

Meningococcal disease during pregnancy is extremely rare. A single reported case occurred more than 20 years ago in England. We present the case of a young woman who just hours after delivery of her baby developed fulminant meningococcal meningitis with its classic findings. Our experience illustrates the importance of early diagnosis and appropriate therapy of meningococcal disease in the gravid as well as in the nongravid population.

The effect of progressive exercise on the equilibrium rebreathing cardiac output method

The equilibrium CO2 rebreathing method has been used in the study of exercise cardiac output (Q) in health and disease, but the requirement for a steady state has usually limited its application to step function exercise. This limits testing to only a few levels of exertion in a laboratory session. We have devised a treadmill test where the grade is flat at the beginning and rises continuously at 1%.min-1 after stable measurements are obtained during level walking. The walking speed is determined by the subject's comfort and tolerance for fast walking. In series I seven normal subjects were studied with this protocol, and an automated system was employed for estimation of Q and oxygen uptake (VO2). For comparison of steady state and progressive tests, an interpolation method was devised which furnished a value of Q (progressive) that could exist at the value of VO2 obtained during the steady state. The average difference in Q so estimated between the steady state and the unsteady state was 0.3 l.min-1, SD = 1.7. This difference was less than the difference between averages of duplicate values of Q obtained during the steady state (1.11.min-1, SD = 16), and the difference between the two differences was not significant. Based on 51 determinations of Q and VO2 in eight normal subjects the unsteady state procedure furnished an average value of the relation slope of delta Q/delta VO2(-1) of 4.8 l.l-1. We conclude that the equilibrium CO2 method can be used to depict the Q, VO2 relationship over the range of VO2 at which rebreathing is tolerable.

Use of phenytoin in the prevention of motion sickness

In a placebo-controlled double-blind crossover pilot study of acute Coriolis-induced motion sickness treatment/prevention in humans employing an anticonvulsant dose of phenytoin, a mean increase in tolerance to motion stress from 4.87 min (S.D. = 5.55) to 46.87 min (S.D. = 32.6) was obtained. This represents a greater than fourfold improvement in efficacy over any currently available single agent and is more than twice as effective as the scopolamine/dexadrine combination. There were none of the usual side effects of blurred vision, dizziness, dry mouth, or sedation.