Association between periodontitis and vitamin D status: A case-control study

Vitamin D deficiency and periodontitis are commonly prevalent among Saudi adults. However, the association between periodontitis and vitamin D status has not been well documented. This study aims to examine the association between periodontitis and vitamin D status among adults in the Albaha region of Saudi Arabia. A case-control study of 123 Saudi adults was conducted; 60 had severe or moderate periodontitis, and 63 were periodontally healthy. Data was collected by an online self-reported sociodemographic questionnaire. All participants then underwent a full periodontal examination. Blood samples were also provided to assess participants’ vitamin D statuses through serum levels of 25-hydroxyvitamin D (25(OH)D). A total of 60 cases and 63 controls matched for BMI (30.2 ± 4.86 kg/m²), age (40.01 ± 7.73 years), and sex (46.3% and 53.7% male and female, respectively) participated in the study. Mean levels of 25(OH)D were significantly lower in periodontitis participants than in controls (25.03 ± 8.55 ng/ml, 29.19 ± 12.82 ng/ml, p = 0.037, respectively). Lower odds of periodontitis were detected per unit of 25(OH)D level (OR 0.964, 95% CI; 0.931–0.999, p = 0.043). In conclusion, periodontitis is significantly associated with deficient and insufficient levels of vitamin D among Saudi adults in the Albaha region. Future longitudinal research with a larger sample size may be suggested to confirm these results.     

A quantitative study of the phytoplankton in the Blue and White Niles at Khartoum

The variation in numbers of the major planktonic algae in the surface waters of the Blue Nile and White Nile were followed for 29 months (August 1968–December 1970). In terms of biomass, the phytoplankton was dominated by diatoms and blue-green algae; other groups were of minor importance. High phytoplankton densities occurred during winter in both rivers, and during summer in the Blue Nile, with values in the latter river greater than in the former. Melosira granulata and its variety angustissima and Anabaena flos-aquae var. intermedia f. spiroides were the most important taxa in the two Niles. Melosira distans and Attheya zachariasi, which are reported for the first time in the present study, preponderated at certain times in the Blue Nile. Microcystisflos-aqua which had been a minor component of the phytoplankton in both rivers during the early 1950s, showed a profuse growth in the Blue Nile. Lyngbya limnetica, Anabaenopsis cunningtonii and A. tanganyikae, which constituted important components of the phytoplankton in the early 1950s, either disappeared or maintained themselves in reduced numbers during the present study. This change in the algal flora of the two Niles may be attributed to the construction of the Roseres dam across the Blue Nile in 1966 and to the invasion of the White Nile by Eichhornia crassipes in 1957.     

Sepsis triggered oxidative stress-inflammatory axis: the pathobiology of reprogramming in the normal sleep–wake cycle

Molecular and Cellular Biochemistry - In individuals with sepsis-related neurodegenerative illness, sleep and circadian rhythm disturbance are common. The alteration in genomic expression linked...     

Micro-morpho-anatomical transitions at various stages of in vitro development of Crinum malabaricum Lekhak and Yadav: A critically endangered medicinal plant

• Crinum malabaricum Lekhak & Yadav is a recently discovered and critically endangered aquatic bulbous plant of the family Amaryllidaceae. It gained attention as a wild source of the acetylcholinesterase inhibiting alkaloid ‘galanthamine’ used to treat Alzheimer and Parkinson diseases. The bulbs of this plant contain the highest amount of galanthamine among Crinum species.
• In vitro regeneration systems were developed to produce quality uniform plantlets of C. malabaricum. Bright field light microscopy was used to analyse micro-morpho-anatomical developments taking place in the leaves and roots during in vitro, ex vitro and in vivo transitions of plantlets.
• Leaves and roots of plants raised in vitro possessed a higher degree of microscopic structural anomalies, such as underdeveloped epicuticular wax deposition, immature and non-functional stomata, more aquiferous parenchyma with a reduced lumen. Roots developed in vitro were characterized by extremely large, uneven cortical cells and reduced intercellular spaces. The vascular tissues were under-developed and only primary vascular tissues were observed. As a result of ex vitro acclimation, there was a significant acceleration in the improvement of tissue systems in leaves and roots. Such plantlets can tolerate elevated temperatures and light under in vivo conditions.
• Thus, the microscopic evaluation of the structural trajectory in different stages of plantlet development provides an understanding of the acclimation process and structural adaptations, which could help enhance survival of in vitro raised plantlets under ex vitro and in vivo conditions.

     

Starch-based extruded plastic films and evaluation of their biodegradable properties

Plastic formulations containing up to 40% starch were prepared and blown into thin films using extrusion methods. Extruded films were evaluated for their biodegradability by exposing them to a consortium of starch degrading bacteria in the laboratory for 45 days and in the ‘La Silla’ river located in Monterrey, N.L. Mexico for up to 60 days. Biodegradability was assessed by measuring changes in weight loss and chemical composition of the films using Fourier transform infrared (FTIR) spectroscopy. While little or no degradation was apparent in control films made up of 100% low density polyethylene (LDPE) or 100% poly-(ethylene-co-acrylic acid) (EAA), most of the starch was depleted in starch-containing films exposed in the river. Starch degradation in films exposed to amylolytic bacteria in the laboratory was relatively slower. Also, increasing the amount of EAA from 25% to 50% substantially reduced starch depletion in these films.     

An efficient micropropagation system for Tylophora indica: an endangered, medicinally important plant

An efficient protocol is described for the rapid in vitro multiplication of an endangered medicinal plant, Tylophora indica (Burm. f.) Merrill, via enhanced axillary bud proliferation from nodal explants collected from young shoots of a two-year-old plant. The physiological effects of growth regulators [6-benzyladenine (BA), kinetin (Kin) thidiazuron (TDZ), indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) or α-naphthalene acetic acid (NAA)], ascorbic acid (AA), different strengths of Murashige and Skoog (MS) medium and various pH levels on in vitro morphogenesis were investigated. The highest number (8.6 ± 0.71) of shoots and the maximum average shoot length (5.2 ± 0.31 cm) were recorded on MS medium supplemented with 2.5 μM BA, 0.5 μM NAA and 100 mg/l AA at pH 5.8. Rooting was best achieved on half-strength MS medium augmented with 0.5 μM IBA. The plantlets regenerated in vitro with well-developed shoot and roots were successfully established in pots containing garden soil and grown in a greenhouse with a 90% survival rate. The regenerated plants did not show any immediate detectable phenotypic variation. The described method can be successfully employed for large-scale multiplication and long-term in vitro conservation of T. indica.     

Purification and properties of an extracellular levansucrase from Erwinia herbicola NRRL B-1678

Levansucrase (EC 2.4.1.10) was purified approximately 40-fold from the extracellular culture fluid of Erwinia herbicola NRRL B-1678. The purified enzyme in its native form occurred as an aggregate. Poly(acrylamide) gel electrophoresis in the presence of sodium dodecyl sulfate showed an active monomer having a molecular weight of 48,000. The enzyme had a K_m for sucrose of 28m and a pH optimum of 6.0, and was stable from −18 to +52°. It was free from - -glucosidase, amylase, and glucansucrase activities, but exhibited considerable β- -fructofuranosidase activity.     

Acid sphingomyelinase-dependent autophagic degradation of GPX4 is critical for the execution of ferroptosis

Ferroptosis is a type of regulated cell death characterized by ROS accumulation and devastating lipid peroxidation (LPO). The role of acid sphingomyelinase (ASM), a key enzyme in sphingolipid metabolism, in the induction of apoptosis has been studied; however, to date its role in ferroptosis is unclear. In this study, we report that ASM plays a hitherto unanticipated role in promoting ferroptosis. Mechanistically, Erastin (Era) treatment results in the activation of ASM and generation of ceramide, which are required for the Era-induced reactive oxygen species (ROS) generation and LPO. Inhibition of nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) or removal of intracellular ROS, significantly reduced Era-induced ASM activation, suggesting that NADPH oxidase-derived ROS regulated ASM-initiated redox signaling in a positive feedback manner. Moreover, ASM-mediated activation of autophagy plays a critical role in ferroptosis inducers (FINs)-induced glutathione peroxidase 4 (GPX4) degradation and ferroptosis activation. Genetic or pharmacological inhibition of ASM diminishes Era-induced features of autophagy, GPX4 degradation, LPO, and subsequent ferroptosis. Importantly, genetic activation of ASM increases ferroptosis in cancer cells induced by various FINs. Collectively, these findings reveal that ASM plays a novel role in ferroptosis that could be exploited to improve pathological conditions that link to ferroptosis.Subject terms: Lipid peroxides, Cancer models, Macroautophagy, Lipid signalling     

Comparison of abacavir-specific effector and proliferating functions of CD8 T cells in abacavir-treated HIV-1 patients

Susceptibility to abacavir hypersensitivity (ABH) in HIV-1-positive patients is strongly linked to the carriage of HLA-B*57:01 and the potential mechanism includes drug-specific activation of cytokine producing CD8 T cells exclusively in individuals carrying HLA-B*57:01. Here, we report a detailed characterization of abacavir-induced functional response of CD8 T cells in HLA-B*57:01^pos individuals. Peripheral blood mononuclear cells (PBMNCs) from HLA-B*57:01^posABH^pos and HLA-B*57:01^negABH^neg individuals were stimulated with abacavir. Multicolor flow cytometry was performed to assess the cytokine (IFNγ) production and degranulation (CD107a expression) after 6–18 hr culture and to enumerate proliferating CD4/CD8 T cells by culturing carboxyfluorescein diacetate succinimidyl ester-loaded PBMNCs for 7 days. CD8 T cells from HLA-B*57:01^posABH^pos individuals were multifunctional: proliferating, IFNγ producing, degranulating (CD107a^pos), and both degranulating and IFNγ producing (CD107a^posIFNγ^pos). Degranulating CD8 T cells in general and both degranulating and IFNγ producing CD8 T cells in particular dominated abacavir-specific immune response. All functional responses were partially blocked by addition of HLA-B*57:01-reactive Bw4 mAb, but not by non-HLA-B*57:01-reactive Bw6 mAb. In conclusion, the study demonstrates that abacavir-specific CD8 T-cell-restricted immune response in HLA-B*57:01^posABH^pos HIV-1 patients has multiple effector and proliferating functions, where the primary effector response appears to be the release of cytolytic granules. The findings have implications for immunotherapy of HLA-related drug hypersensitivities.     

O-diphenoloxidase concentrations in leprosy.

O-diphenoloxidase activity was studied in 15 patients with lepromatous leprosy, 15 with tuberculois leprosy, and 15 controls. O-diphenoloxidase isolated from skin and serum samples of patients with lepromatous leprosy had the specificity of a bacterially derived enzyme and not that of a mammalian-derived enzyme. Only the patients who had lepromatous leprosy for over two years showed enzyme activity in serum, though all showed it in skin tissue. O-diphenoloxidase activity in serum may be a useful diagnostic marker of lepromatous leprosy.