The literature about salivary lactate dehydrogenase (LDH) activity shows different results, conditioned by the diversity of methods used for sampling, handling and analysis.
Objetives: The aim of ...this study was to design a protocol for quantifying salivary lactate dehydrogenase activity.
Methods: Whole saliva samples were collected from 100 healthy volunteers by chewing a roll of cotton. Lactate dehydrogenase activity determinations were made with the Cobas Mira Plus II
® autoanalyser using the recommendations proposed by the International Federation of Clinical Chemistry (IFCC) and the French Society of Clinical Biology (SFBC). Samples were stored at room temperature (20–22
°C), in the refrigerator (4
°C) and freezer (−20
°C). The correction capacity of the autoanalyser was evaluated by making serial determinations in samples of saliva diluted in water.
Results: The frozen samples, but not those stored in the refrigerator or at room temperature, showed an important degradation of lactate dehydrogenase activity. When the samples were diluted in water, the lactate dehydrogenase activity varied substantially with the International Federation of Clinical Chemistry method after correction, but not when using the French Society of Clinical Biology method.
Conclusion: For salivary lactate dehydrogenase activity quantification we suggest that samples be stored at 4
°C and analyse with the French Society of Clinical Biology method.
The development of spinal cord interneurons and the formation of interneuronal synaptic connections has received little attention; the most comprehensively studied developing circuit has been the ...connection between motoneurons and the muscle they innervate. All motoneurons are cholinergic whereas spinal interneurons are mostly glutamatergic, glycinergic or GABAergic neurons. In this study, we show quantitative data, obtained by high-pressure liquid chromatography (HPLC), on the levels of amino acid neurotransmitters during mouse spinal cord neurogenesis, from embryonic day (E) 12 until postnatal day (P) 30. At E12, high levels of glutamate, glycine and taurine were already detected but between E16 and P3, significant increments in their contents were observed, indicating the occurrence of maximum synaptogenesis during this period. Important reductions in their contents were also observed in two stages: between E12-E16 and P3-P7. These results suggest that the apoptotic death of interneurons and motoneurons in the developing brain or the synapse refinement of neural circuitry during maturation reduced the number of synapses, thereby decreasing the levels of neurotransmitters. The contents of these neurotransmitters were also analyzed in primary cultures of mouse spinal cord prepared from embryos between E13 and E19. As deduced from light microscopy, ultrastructural studies, as well as results from HPLC analysis, the cultures derived from E15-E16 embryos showed the highest degree of histotypic features and neurotransmitter contents comparable with those obtained in situ. Although glycine, GABA and taurine levels reached about 80-90% of normal in situ values, the contents of aspartate and glutamate were lower by about 40%, which could be mainly due to deafferentation of both sensory and supraspinal afferent axon terminals. These results indicate that intrinsic synaptic circuits can be maintained in histotypic spinal cord cultures prepared from E15-E16 mouse embryos. Histotypic cultures of the spinal cord will serve as a good model for studies on the pathophysiology of amino-acid-based neurotransmission and repair strategies in many CNS disorders.
The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary ...asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 minutes was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (\(\beta\)) was possible. In the years prior to impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 +/- 1.0 (3\(\sigma\)) minutes. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a significant amount of momentum to the asteroid beyond what the DART spacecraft carried.
Hodgkin lymphoma is a highly curable disease.
To evaluate the clinical characteristics and the treatment results of Hodgkin lymphoma patients of the National Cancer Program in Chile.
Prospective ...assessment of 682 patients treated in 18 adult cancer centers. Progression free survival (PFS) and overall survival (OS) were calculated. Median follow up was 127, 95, 87, 72 and 50 months for C-MOPP, radiotherapy (RT), C-MOPP/ABV, NOVP and ABVD, respectively.
Median age was 37 years (15-84). Nodular sclerosis and mixed cellularity were equally expressed. Advanced stages (III & IV) were present at diagnosis in 61% of cases. Age over 40 was an adverse prognostic factor (p<0.001). The rate of PFS at 5 and 10 years for early stages was 73% and 66% with RT, 80% and 74% with C-MOPP+RT, 73% and 71% with C-MOPP/ABV, 59% and 59% with NOVP+RT, and 81% with ABVD+RT, at 5 years, being significantly lower for NOVP (p=0.02). The rate of OS at 5 and 10 years for advanced stages was 82% and 70% with RT, 82% and 76% with C-MOPP+RT, 82% and 80% with C-MOPP/ABV, 68% and 60% with NOVP, and 85% with ABVD at 5 years, also significantly lower for NOVP (p=0.04). For advanced stages, the rate of PFS at 5 and 10 years was 49% and 43% with C-MOPP, 69% and 62% with C-MOPP/ABVD or C-MOPP/ABV, and 71% at 5 years with ABVD, significantly lower for C-MOPP (p=0.01). The rate of OS at 5 and 10 years was 52% and 46% with C-MOPP, 70% and 63% with C-MOPP/ABVD or C-MOPP/ABV and 76% with ABVD at 5 years, significantly lower for C-MOPP (p=0.0002).
Age over 40 years was an adverse prognostic factor. C-MOPP/ABVD, C-MOPP/ABV and ABVD had comparable results and reached a high tumor control and overall survival in both early and advanced stages.
To determine Lactate Dehydrogenase Activity (LDHA) in whole saliva in individuals with periodontal disease and the effect of ultrasonic scaling on this enzyme activity.
A study group of 50 patients ...with PD (Community Periodontal Index of Treatment Needs > or = 3) was selected at random. Half of the patients (n=25) received ultrasonic periodontal treatment (Group 1). In the other 25 patients with PD the ultrasonic scaling was not performed (Group 2). A control group was selected (Group 3) consisting of 25 adults without PD (Community Periodontal Index of Treatment Needs = 0), with age and gender distribution similar to the study group. LDHA determinations were carried out with a Cobas Mira Plus II autoanalyzer pursuant to the recommendations of the French Society of Clinical Biology. A baseline determination of LDHA was carried out on all the participants and a second determination was performed 3 months later.
Baseline determination of LDHA was higher in patients with PD than in the control group. These differences were statistically significant (P< 0.001). LDHA was significantly reduced in patients with PD after ultrasonic scaling with respect to baseline determination (P< 0.0001). LDHA differences between Groups 2 and 3 were statistically significant (P< 0.0001), but it was not so between Groups 1 and 3.