Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Pediatr Emerg Care ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849150

ABSTRACT

OBJECTIVE: Screening for blunt intra-abdominal injury in children often includes directed laboratory evaluation that guides need for computed tomography. We sought to evaluate the use of urinalysis in identifying patients with clinically important intraabdominal injury (ci-IAI). METHODS: A retrospective chart review was performed for all patients less than 18 years who presented with blunt mechanisms at a level I trauma center between 2016 and 2019. Exclusion criteria included transfer from an outside facility, physical abuse, and death within thirty minutes of arrival. Demographics, physical exam findings, serum chemistries, urinalysis, and imaging were reviewed. Clinically important intraabdominal injury was defined as injury requiring ≥2 nights admission, blood transfusion, angiography with embolization, or therapeutic surgery. RESULTS: Two hundred forty patients were identified. One hundred sixty-five had a completed urinalysis. For all patients an abnormal chemistry panel and abnormal physical exam had a sensitivity of 88.9% and a negative predictive value of 99.3%. Nine patients had a ci-IAI. Patients with a ci-IAI were more likely to have abdominal pain, tenderness on exam, and elevated hepatic enzymes. When patients were stratified by the presence of an abnormal chemistry or physical exam with or without microscopic hematuria, urinalysis did not improve the ability to identify patients with a ci-IAI. In fact, presence of microscopic hematuria increased the rate of false positives by 12%. CONCLUSIONS: Microscopic hematuria was not a useful marker for ci-IAI and may lead to falsely assuming a more serious injury.

2.
JPRAS Open ; 39: 49-59, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38162533

ABSTRACT

Microvascular free tissue transfer surgery is a frequently used technique for head and neck reconstruction involving anticoagulants, and the present study aimed to analyse the postoperative outcomes of aspirin use in conjunction with this procedure. We searched databases for articles published between 2007 and 2022 on microvascular free tissue transfer surgery using aspirin and assessed them for primary and secondary outcomes. Odds ratios (ORs) and 95 % confidence intervals (CIs) were determined through analyses, followed by constructing a forest plot for complication rates. A total of 617 articles were retrieved from the databases, including 14 original full-text articles. Overall complication rates ranged from 0.7-38 % (95 % CI, 17.85 ± 0.503 (±2.8 %) [17.347-18.353]), while flap survival rates ranged from 95-99.2 % (95 % CI, 96.28 ± 0.0956 (±0.10 %) [96.184-96.376]). Two studies reported similar complication rates of 38 %, the highest among all reported studies. The ORs between the studies for the complications and flap survival rates were 2.614 and 0.722, respectively. Although the complication rates associated with aspirin use were not significantly high among the studies, they cannot be ignored. Flap survival rates were independent of the dose and type of anticoagulants used during surgery.

3.
J Pediatr Surg ; 58(6): 1200-1205, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36925399

ABSTRACT

BACKGROUND: Venous thromboembolism (VTE) causes significant morbidity in pediatric trauma patients. We applied machine learning algorithms to the Trauma Quality Improvement Program (TQIP) database to develop and validate a risk prediction model for VTE in injured children. METHODS: Patients ≤18 years were identified from TQIP (2017-2019, n = 383,814). Those administered VTE prophylaxis ≤24 h and missing the outcome (VTE) were removed (n = 347,576). Feature selection identified 15 predictors: intubation, need for supplemental oxygen, spinal injury, pelvic fractures, multiple long bone fractures, major surgery (neurosurgery, thoracic, orthopedic, vascular), age, transfusion requirement, intracranial pressure monitor or external ventricular drain placement, and low Glasgow Coma Scale score. Data was split into training (n = 251,409) and testing (n = 118,175) subsets. Machine learning algorithms were trained, tested, and compared. RESULTS: Low-risk prediction: For the testing subset, all models outperformed the baseline rate of VTE (0.15%) with a predicted rate of 0.01-0.02% (p < 2.2e-16). 88.4-89.4% of patients were classified as low risk by the models. HIGH-RISK PREDICTION: All models outperformed baseline with a predicted rate of VTE ranging from 1.13 to 1.32% (p < 2.2e-16). The performance of the 3 models was not significantly different. CONCLUSION: We developed a predictive model that differentiates injured children for development of VTE with high discrimination and can guide prophylaxis use. LEVEL OF EVIDENCE: Prognostic, Level II. TYPE OF STUDY: Retrospective, Cross-sectional.


Subject(s)
Venous Thromboembolism , Humans , Child , Venous Thromboembolism/epidemiology , Venous Thromboembolism/etiology , Venous Thromboembolism/prevention & control , Retrospective Studies , Cross-Sectional Studies , Risk Factors , Algorithms , Machine Learning
4.
Front Microbiol ; 13: 832054, 2022.
Article in English | MEDLINE | ID: mdl-35350619

ABSTRACT

"Ancestral" Mycobacterium tuberculosis complex (MTBC) strains of Lineage 1 (L1, East African Indian) are a prominent tuberculosis (TB) cause in countries around the Indian Ocean. However, the pathobiology of L1 strains is insufficiently characterized. Here, we used whole genome sequencing (WGS) of 312 L1 strains from 43 countries to perform a characterization of the global L1 population structure and correlate this to the analysis of the synthesis of phenolic glycolipids (PGL) - known MTBC polyketide-derived virulence factors. Our results reveal the presence of eight major L1 sub-lineages, whose members have specific mutation signatures in PGL biosynthesis genes, e.g., pks15/1 or glycosyltransferases Rv2962c and/or Rv2958c. Sub-lineage specific PGL production was studied by NMR-based lipid profiling and strains with a completely abolished phenolphthiocerol dimycoserosate biosynthesis showed in average a more prominent growth in human macrophages. In conclusion, our results show a diverse population structure of L1 strains that is associated with the presence of specific PGL types. This includes the occurrence of mycoside B in one sub-lineage, representing the first description of a PGL in an M. tuberculosis lineage other than L2. Such differences may be important for the evolution of L1 strains, e.g., allowing adaption to different human populations.

5.
Cureus ; 14(12): e33142, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36721591

ABSTRACT

Scarlet fever is an infectious illness, which is caused by Streptococcus pyogenes. It causes exanthema and a characteristic tonsillopharyngitis. Its diagnosis is typically straightforward. However, due to the diverse clinical presentation of scarlet fever, one has to be cautious about atypical rash distribution that might go unrecognized or be misdiagnosed. Despite the fact that scarlet fever is primarily a pediatric illness, it can affect people of any age group. The case presented describes the clinical difficulty in the diagnosis of scarlet fever in an adult patient with atypical rash distribution involving dorsum of the hand and feet only till the level of wrists and ankles joints. A high degree of suspicion is required to diagnose this rare presentation and early treatment is essential to limit the spread of the disease.

6.
J Infect Public Health ; 13(1): 154-157, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31431418

ABSTRACT

We describe the clinical and genetic characteristics of multi-drug resistant tuberculosis (MDR-TB) in a family cluster in the western region of Kingdom of Saudi Arabia diagnosed between 2012 and 2016. All cases had risk factors for tuberculosis acquisition and they were not household contacts of the index case. Genetic analysis detected both MDR-TB and pre-extensively drug-resistant tuberculosis (pre-XDR TB) strains in the index case and confirmed tuberculosis transmission between two cases. Lack of early diagnosis of MDR-TB by molecular testing and lack of extended contact tracing contributed to the transmission of MDR-TB among this family cluster over four years.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Family , Mycobacterium tuberculosis/genetics , Thorax/diagnostic imaging , Tuberculosis, Multidrug-Resistant/diagnosis , Adult , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Extensively Drug-Resistant Tuberculosis/drug therapy , Female , Humans , Infant , Male , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Saudi Arabia , Thorax/microbiology , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/microbiology
8.
Int Orthod ; 13(3): 287-301, 2015 Sep.
Article in English, French | MEDLINE | ID: mdl-26277455

ABSTRACT

OBJECTIVE: To compare the percentage force decay of clear and semi-clear elastomeric chain products from eight different manufacturers and to evaluate the amount of discoloration after immersion in colored dietary media of the same elastomeric chain products. MATERIAL AND METHODS: An in vitro study was designed using an electronic force gauge to measure six samples from each of 19 types of elastomeric chains stretched for a period of four weeks. A spectrophotometer was used to measure the color of each specimen (10 of each type) at baseline and after being soaked in a dietary medium (coffee, tea, cola, and wine in 250 ml amounts) for 72 h. RESULTS: There was a significant difference in the percentage of the lost initial force between all the tested E-chains (P<0.001). ANOVA shows a significant difference in the amount of discoloration between the E-chain types (P<0.001). Semi-clear (tooth-color/pearl/obscure) E-chain types (TP-ToothC, OrthO-Pearl, GAC-SiliPearl, 3M-Obscure) present significantly less change in color than clear E-chains of the same brand (TP-Clear, OrthoO-Clear, GAC-SiliClear, 3M-Clear). CONCLUSIONS: Significant differences in the mean percentage force decay between the 19 studied clear elastomeric chain types were present. AO-Memory and Ormco maintained most of their original force at the end of the four-week interval. Significant differences in discoloration also exist between the various types of E-chains. TP Orthodontics (Tooth-Colored, SuperSlick, Clear) and Ortho Organizers (Pearl) showed the least discoloration.


Subject(s)
Elastomers/chemistry , Orthodontic Appliances , Carbonated Beverages , Coffee , Color , Elasticity , Humans , Materials Testing , Orthodontic Appliance Design , Spectrophotometry/instrumentation , Stress, Mechanical , Surface Properties , Tea , Time Factors , Wine
9.
Ann Saudi Med ; 32(3): 312-4, 2012.
Article in English | MEDLINE | ID: mdl-22588446

ABSTRACT

Mycobacterium abscessus is a rapidly growing non-tuberculous mycobacterium that is a common water contaminant, and an exclusive opportunistic pathogen in immunosuppressed patients; however, it occasionally causes lung infections in immunocompetent persons as well. We report two cases of chronic pulmonary infection caused by M abscessus in two young migrant workers; they were nonreactive to HIV antigen, without any history of pulmonary disorders and no evidence of any immunocompromized status. Both were initially suspected as having pulmonary tuberculosis, and antituberculosis drugs were administered. The preliminary culture found the isolate as a rapidly growing nontuberculous mycobacteria and later by advanced molecular genotyping of the isolates revealed it as M abscessus. The patients were treated with multiple drugs including clarithromycin. The symptoms resolved slowly, the smears and culture became negative, and they recovered completely. This is the first case of its type to be reported from Saudi Arabia.


Subject(s)
Lung/microbiology , Mycobacterium Infections/diagnosis , Mycobacterium Infections/microbiology , Nontuberculous Mycobacteria , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/microbiology , Tuberculosis, Pulmonary/diagnosis , Adult , Diagnosis, Differential , Humans , Immunocompetence , Male , Saudi Arabia , Transients and Migrants
10.
J Clin Microbiol ; 48(10): 3813-6, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20686077

ABSTRACT

Five Mycobacterium tuberculosis isolates were obtained from three body sites from a Dutch patient. The isolates displayed a single genotype by 24-locus MIRU-VNTR typing (except for a single locus not amplified from one isolate) but were differentiated by small variations in IS6110 fingerprints, spoligotypes, 6 hypervariable MIRU-VNTR loci, and/or DiversiLab profiles, revealing patterns of microevolution in a clonal infection.


Subject(s)
Bacterial Typing Techniques , DNA Fingerprinting , Evolution, Molecular , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/genetics , Tuberculosis/microbiology , Cluster Analysis , DNA Transposable Elements , DNA, Bacterial/genetics , Female , Genotype , Humans , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Netherlands
11.
Saudi Med J ; 30(12): 1515-9, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19936412

ABSTRACT

OBJECTIVE: To investigate possible cross-contamination events of Mycobacterium tuberculosis cultures, and also to shed light on cross-contamination problems in our laboratories. METHODS: At the TB Research Unit in the Department of Comparative Medicine Research Centre of King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia, we received 22 TB isolates sub-cultured on Lowenstein-Jensen media from a local laboratory in Riyadh on 1st July 2005. We finger printed all 22 isolates in question using a polymerase chain reaction-based spoligotype molecular technique. The epidemiological and clinical data were reviewed. RESULTS: All 22 cases had been proven to be cross-contaminated as a result of processing all specimens using a contaminated buffer. All of these patients had no clinical course consistent with tuberculosis. The discordant clinical pictures, and a deoxyribonucleic acid fingerprint that matches those of other culture-positive specimens processed concurrently, in addition to a lack of an epidemiological link between the patients suggest cross-contamination events. CONCLUSION: Using molecular techniques has become an absolute necessity to detect cross-contamination events in our laboratory, to prevent the deleterious consequences of cross-contamination in patients.


Subject(s)
Microbiological Techniques , Mycobacterium tuberculosis/classification , Humans , Laboratories , Mycobacterium tuberculosis/genetics , Quality Control
12.
Int J Syst Evol Microbiol ; 59(Pt 5): 1049-53, 2009 May.
Article in English | MEDLINE | ID: mdl-19406791

ABSTRACT

A non-chromogenic, slowly growing Mycobacterium strain was isolated from a maxillary sinus lavage from a symptomatic patient in Riyadh, Saudi Arabia. It was initially identified as a member of the Mycobacterium tuberculosis complex by a commercial line-probe assay. Its 16S rRNA, hsp65 and rpoB gene and 16S-23S internal transcribed spacer sequences were unique; phylogenetic analysis based on the 16S rRNA gene sequence groups this organism close to Mycobacterium szulgai and Mycobacterium malmoense. Its unique biochemical properties and mycolic acid profile support separate species status. We propose the name Mycobacterium riyadhense sp. nov. to accommodate this strain. The type strain is NLA000201958(T) (=CIP 109808(T) =DSM 45176(T)).


Subject(s)
Diagnostic Errors , Maxillary Sinus/microbiology , Maxillary Sinusitis , Mycobacterium tuberculosis/isolation & purification , Mycobacterium/classification , Reagent Kits, Diagnostic , Adult , Bacterial Proteins/genetics , DNA, Bacterial/analysis , DNA, Bacterial/genetics , DNA, Ribosomal Spacer/genetics , Genes, rRNA , Humans , Male , Maxillary Sinusitis/diagnosis , Maxillary Sinusitis/microbiology , Molecular Probe Techniques , Molecular Sequence Data , Mycobacterium/genetics , Mycobacterium/isolation & purification , Mycobacterium/physiology , Mycobacterium Infections/diagnosis , Mycobacterium Infections/microbiology , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/genetics , Mycolic Acids/analysis , Phylogeny , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , Saudi Arabia , Sequence Analysis, DNA , Species Specificity , Therapeutic Irrigation , Tuberculosis/diagnosis , Tuberculosis/microbiology , Young Adult
13.
J Bone Joint Surg Am ; 90 Suppl 2 Pt 1: 1-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18310682

ABSTRACT

BACKGROUND: Recent studies have shown a high prevalence of symptomatic malunion and nonunion after nonoperative treatment of displaced midshaft clavicular fractures. We sought to compare patient-oriented outcome and complication rates following nonoperative treatment and those after plate fixation of displaced midshaft clavicular fractures. METHODS: In a multicenter, prospective clinical trial, 132 patients with a displaced midshaft fracture of the clavicle were randomized (by sealed envelope) to either operative treatment with plate fixation (sixty-seven patients) or nonoperative treatment with a sling (sixty-five patients). Outcome analysis included standard clinical follow-up and the Constant shoulder score, the Disabilities of the Arm, Shoulder and Hand (DASH) score, and plain radiographs. One hundred and eleven patients (sixty-two managed operatively and forty-nine managed nonoperatively) completed one year of follow-up. There were no differences between the two groups with respect to patient demographics, mechanism of injury, associated injuries, Injury Severity Score, or fracture pattern. RESULTS: Constant shoulder scores and DASH scores were significantly improved in the operative fixation group at all time-points (p = 0.001 and p < 0.01, respectively). The mean time to radiographic union was 28.4 weeks in the nonoperative group compared with 16.4 weeks in the operative group (p = 0.001). There were two nonunions in the operative group compared with seven in the nonoperative group (p = 0.042). Symptomatic malunion developed in nine patients in the nonoperative group and in none in the operative group (p = 0.001). Most complications in the operative group were hardware-related (five patients had local irritation and/or prominence of the hardware, three had a wound infection, and one had mechanical failure). At one year after the injury, the patients in the operative group were more likely to be satisfied with the appearance of the shoulder (p = 0.001) and with the shoulder in general (p = 0.002) than were those in the nonoperative group. CONCLUSIONS: Operative fixation of a displaced fracture of the clavicular shaft results in improved functional outcome and a lower rate of malunion and nonunion compared with nonoperative treatment at one year of follow-up. Hardware removal remains the most common reason for repeat intervention in the operative group. This study supports primary plate fixation of completely displaced midshaft clavicular fractures in active adult patients.


Subject(s)
Bone Plates , Clavicle/injuries , Fracture Fixation, Internal/methods , Fractures, Bone/surgery , Fractures, Malunited/epidemiology , Fractures, Ununited/epidemiology , Humans , Postoperative Care , Prospective Studies , Recovery of Function , Suture Techniques , Treatment Outcome
14.
J Clin Microbiol ; 45(8): 2467-73, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17507515

ABSTRACT

This study constitutes a first attempt to describe the genetic population structure and drug resistance of the tubercle bacilli circulating in Saudi Arabia. A total of 1,505 clinical isolates of M. tuberculosis, isolated between 2002 and 2005 from seven regions of Saudi Arabia, were studied. The sample studied showed a male-to-female sex ratio of 1.27, with half of the cases among foreign-born individuals and 47% within the 21- to 40-year-old age group; a total resistance rate of 19.7%; and multiple drug resistance of 4.5%. Upon spoligotyping, a total of 387 individual patterns were obtained (clustering rate, 86.4%; 182 clusters containing between 2 and 130 isolates per cluster). A total of 94% of the strains matched the spoligotype patterns in an international database. Nearly 81% of the isolates in this study belonged to established phylogeographic clades: Central Asian (CAS), 22.5%; ill-defined T clade, 19.5%; East African-Indian (EAI), 13.5%; Haarlem, 7.5%; Latin American-Mediterranean, 7.2%; Beijing, 4.4%; Manu, 2.7%; X, 0.9%; and Bovis, 0.9%. Two clonal complexes with unique spoligotyping signatures (octal codes 703777707770371 and 467777377413771) specific to Saudi Arabia were identified. These belonged to the CAS and EAI clades, respectively, as confirmed upon secondary typing using mycobacterial interspersed repetitive units (MIRUs). The results obtained underline the predominance of historic clones of principal genetic group 1, which are responsible for roughly 45% of all tuberculosis cases in Saudi Arabia. The high rate of clustering observed might be an indication of rapid ongoing transmission within certain communities and/or subpopulations in Saudi Arabia; nonetheless, spoligotyping is known to overestimate clustering, and only a systematic second-line typing, such as MIRUs, coupled with a better tuberculosis registry and epidemiological investigations would allow us to know the exact rate of ongoing transmission and associated risk factors in Saudi Arabia.


Subject(s)
Bacterial Typing Techniques , DNA, Bacterial/genetics , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Antitubercular Agents/pharmacology , Child , Child, Preschool , Cluster Analysis , Drug Resistance, Multiple, Bacterial , Female , Genotype , Humans , Infant , Interspersed Repetitive Sequences/genetics , Male , Middle Aged , Molecular Epidemiology , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Saudi Arabia/epidemiology , Tuberculosis/epidemiology
16.
Saudi Med J ; 28(2): 268-70, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17268708

ABSTRACT

This study represents the first time that molecular tracing techniques have been used to identify patterns of tuberculosis TB infection in Saudi Arabia. The 2 strains were isolated from a socio-economically advantage family who share a number of common facilities including a car and a driver. There are several factors that may play vital roles in on-going transmission of TB in Saudi Arabia including a high number of expatriates, the Hajj pilgrimage, and the social habits of Saudi citizens. Our sibling case series is believed to be a frequent pattern of disease transmission in this country. Control measures such as health education, active case finding, and prompt and supervised medical treatment are needed. More studies using molecular techniques are recommended to find the incidence of cross infection in Saudi Arabia. In addition, molecular techniques have to be established in all reference laboratories to help the detection of ongoing active transmission, molecular epidemiology and detect sources of infection.


Subject(s)
Disease Transmission, Infectious , Mycobacterium tuberculosis/isolation & purification , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/transmission , Adolescent , Adult , Antitubercular Agents/therapeutic use , DNA, Bacterial/analysis , Female , Humans , Male , Molecular Biology , Polymerase Chain Reaction , Risk Assessment , Saudi Arabia , Siblings , Treatment Outcome , Tuberculosis, Pulmonary/drug therapy
17.
BMC Microbiol ; 6: 23, 2006 Mar 06.
Article in English | MEDLINE | ID: mdl-16519816

ABSTRACT

BACKGROUND: The Direct Repeat locus of the Mycobacterium tuberculosis complex (MTC) is a member of the CRISPR (Clustered regularly interspaced short palindromic repeats) sequences family. Spoligotyping is the widely used PCR-based reverse-hybridization blotting technique that assays the genetic diversity of this locus and is useful both for clinical laboratory, molecular epidemiology, evolutionary and population genetics. It is easy, robust, cheap, and produces highly diverse portable numerical results, as the result of the combination of (1) Unique Events Polymorphism (UEP) (2) Insertion-Sequence-mediated genetic recombination. Genetic convergence, although rare, was also previously demonstrated. Three previous international spoligotype databases had partly revealed the global and local geographical structures of MTC bacilli populations, however, there was a need for the release of a new, more representative and extended, international spoligotyping database. RESULTS: The fourth international spoligotyping database, SpolDB4, describes 1939 shared-types (STs) representative of a total of 39,295 strains from 122 countries, which are tentatively classified into 62 clades/lineages using a mixed expert-based and bioinformatical approach. The SpolDB4 update adds 26 new potentially phylogeographically-specific MTC genotype families. It provides a clearer picture of the current MTC genomes diversity as well as on the relationships between the genetic attributes investigated (spoligotypes) and the infra-species classification and evolutionary history of the species. Indeed, an independent Naïve-Bayes mixture-model analysis has validated main of the previous supervised SpolDB3 classification results, confirming the usefulness of both supervised and unsupervised models as an approach to understand MTC population structure. Updated results on the epidemiological status of spoligotypes, as well as genetic prevalence maps on six main lineages are also shown. Our results suggests the existence of fine geographical genetic clines within MTC populations, that could mirror the passed and present Homo sapiens sapiens demographical and mycobacterial co-evolutionary history whose structure could be further reconstructed and modelled, thereby providing a large-scale conceptual framework of the global TB Epidemiologic Network. CONCLUSION: Our results broaden the knowledge of the global phylogeography of the MTC complex. SpolDB4 should be a very useful tool to better define the identity of a given MTC clinical isolate, and to better analyze the links between its current spreading and previous evolutionary history. The building and mining of extended MTC polymorphic genetic databases is in progress.


Subject(s)
Databases, Factual , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/genetics , Polymorphism, Genetic , Tuberculosis/epidemiology , Computational Biology , Genetics, Population , Mycobacterium tuberculosis/isolation & purification , Phylogeny , Serotyping
18.
Saudi Med J ; 25(11): 1545-8, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15573175

ABSTRACT

There is no doubt that the laboratory is the backbone for the diagnosis of tuberculosis (TB). Only through testing in the laboratory can the physician confirm suspicion of TB despite any previous clinical and x-ray findings. Recent visits to several laboratories in the Kingdom of Saudi Arabia showed that some need considerable improvement. Unless there are standardized procedures to diagnose TB, and safety measures are implemented in all laboratories, it will be impossible to diagnose accurately and control TB. The laboratories should be redesigned to conform to international TB Diagnostic Centers, with well trained staff and proper safety procedures.


Subject(s)
Bacteriological Techniques/standards , Clinical Laboratory Techniques/standards , DNA Fingerprinting/standards , Tuberculosis, Pulmonary/diagnosis , Humans , Laboratories, Hospital/standards , Laboratory Infection/prevention & control , Quality Control , Saudi Arabia , Tuberculosis, Pulmonary/prevention & control
19.
J Physiol ; 527 Pt 2: 213-23, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10970424

ABSTRACT

Noradrenaline is known to suppress transmission from group II muscle afferents when locally applied to gamma-motoneurones, and serotonin (5-HT) facilitates the transmission. The purpose of this investigation was to search for evidence of monoaminergic innervation of gamma-motoneurones. Eight gamma-motoneurones were labelled with rhodamine-dextran, and 50 micrometer thick sagittal sections of the spinal cord containing them were exposed to antibodies against dopamine beta-hydroxylase (DBH) and 5-HT. All the cells were directly and/or indirectly excited by muscle group II afferents from the muscle they innervated and/or other muscles. Appositions between monoaminergic fibres and the labelled somata and dendrites were located with three-colour confocal laser scanning microscopy by examining series of optical sections at 1 or 0.5 micrometer intervals. DBH and 5-HT varicosities formed appositions with the somata and dendrites of all the gamma-motoneurones. The mean packing densities for 5-HT (1.12 +/- 0.11 appositions per 100 micrometer(2) for somata and 0.91 +/- 0.07 per 100 micrometer(2) for dendrites) were similar to the densities of contacts reported for alpha-motoneurones. Monoaminergic varicosities in apposition to dendrites greatly outnumbered those on the somata. The density of DBH appositions was consistently lower - corresponding means were 53% and 62% of those for 5-HT on the somata and dendrites, respectively. It is concluded from an analysis of the distribution and density of varicosities in apposition to the gamma-motoneurones compared with the density in the immediate surround of the dendrites that there is indeed both a serotoninergic and noradrenergic innervation of gamma-motoneurones.


Subject(s)
Motor Neurons, Gamma/physiology , Neurons/physiology , Norepinephrine/physiology , Serotonin/physiology , Animals , Cats , Cell Communication/physiology , Dendrites/physiology , Dextrans , Dopamine beta-Hydroxylase/metabolism , Hindlimb/innervation , Image Processing, Computer-Assisted , Microscopy, Confocal , Motor Neurons, Gamma/ultrastructure , Nerve Fibers/physiology , Neurons/ultrastructure , Rhodamines , Spinal Cord/cytology
20.
Ophthalmic Physiol Opt ; 17(6): 516-21, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9666926

ABSTRACT

A subjective assessment of the optical quality of the human eye may be derived from a comparison between the contrast sensitivities obtained in response to a refracted grating display and a non-refracted grating display. The former may be generated on a cathode ray tube (CRT) while the latter may be obtained with laser interference fringes observed in the Maxwellian view. With this method, the rate of decline of the contrast ratio of the optical media with increasing spatial frequency has been shown to be appreciably less than the rate of decline of the neural performance represented by the laser contrast sensitivities. However, this comparison has been based on results in response to a green CRT display and red (Helium-Neon) interference fringes. In the present study, we have confirmed this result with respect to comparisons between a green CRT display and a green laser display, although the absolute value of the contrast ratio of the optical media for the green laser display was reduced compared with values for the red laser display.


Subject(s)
Contrast Sensitivity , Visual Perception , Helium , Humans , Lasers , Neon , Vision Tests/instrumentation
SELECTION OF CITATIONS
SEARCH DETAIL
...