A p90(rsk) mutant constitutively interacting with MAP kinase uncouples MAP kinase from p34(cdc2)/cyclin B activation in Xenopus oocytes

The efficient activation of p90(rsk) by MAP kinase requires their interaction through a docking site located at the C-terminal end of p90(rsk). The MAP kinase p42(mpk1) can associate with p90(rsk) in G(2)-arrested but not in mature Xenopus oocytes. In contrast, an N-terminally truncated p90(rsk) mutant named D2 constitutively interacts with p42(mpk1). In this report we show that expression of D2 inhibits Xenopus oocyte maturation. The inhibition requires the p42(mpk1) docking site. D2 expression uncouples the activation of p42(mpk1) and p34(cdc2)/cyclin B in response to progesterone but does not prevent signaling through p90(rsk). Instead, D2 interferes with a p42(mpk1)-triggered pathway, which regulates the phosphorylation and activation of Plx1, a potential activator of the Cdc25 phosphatase. This new pathway that links the activation of p42(mpk1) and Plx1 during oocyte maturation is independent of p34(cdc2)/cyclin B activity but requires protein synthesis. Using D2, we also provide evidence that the sustained activation of p42(mpk1) can trigger nuclear migration in oocytes. Our results indicate that D2 is a useful tool to study MAP kinase function(s) during oocyte maturation. Truncated substrates such as D2, which constitutively interact with MAP kinases, may also be helpful to study signal transduction by MAP kinases in other cellular processes.

The localization of facial motor impairment in sporadic Mobius syndrome

OBJECTIVE

To investigate the neurophysiologic aspects of facial motor control in patients with sporadic Möbius syndrome defined as nonprogressive congenital facial and abducens palsy.

METHODS

The authors assessed 24 patients with sporadic Möbius syndrome by performing a complete clinical examination and neurophysiologic tests including facial nerve conduction studies, needle electromyography examination of facial muscles, and recording of the blink reflex and of the trigeminofacial inhibitory reflex.

RESULTS

Two distinct groups of patients were identified according to neurophysiologic testing. The first group was characterized by increased facial distal motor latencies (DMLs) and poor recruitment of small and polyphasic motor unit action potentials (MUAPs). The second group was characterized by normal facial DMLs and neuropathic MUAPs. It is hypothesized that in the first group, the disorder is due to a rhombencephalic maldevelopment with selective sparing of small-size MUs, and in the second group, the disorder is related to an acquired nervous injury during intrauterine life, with subsequent neurogenic remodeling of MUs. The trigeminofacial reflexes showed that in most subjects of both groups, the functional impairment of facial movements was caused by a nuclear or peripheral site of lesion, with little evidence of brainstem interneuronal involvement.

CONCLUSION

Two different neurophysiologically defined phenotypes can be distinguished in sporadic Möbius syndrome, with different pathogenetic implications.

Pathological yawning as a presenting symptom of brain stem ischaemia in two patients

Two cases of brain stem stroke involving the upper pons and the ponto-mesencephalic junction presented with transient excessive pathological yawning, associated with gait ataxia and in one subject with upper limb and facial hemiparesis. A causal relation is hypothesised between the brain stem lesion and pathological yawning, possibly related to denervation hypersensitivity of a putative brain stem yawn centre. Excessive yawning may herald brain stem ischaemia.

Variations of antioxidant efficiency and presence of endosymbiotic diatoms in the Antarctic porifera Haliclona dancoi

The role of endosymbiotic diatoms as pro-oxidant stressors in porifera has been investigated in the Antarctic sponge Haliclona dancoi in which the presence of diatoms is influenced by marked seasonal variations during the austral summer. Both chlorophaeopigments and frustules were absent in sponge tissues sampled in early November at the beginning of the summer and increased from the mid of December with slightly shifted temporal trends. The efficiency of antioxidant defenses in the sponge showed a marked response to symbionts with clearly enhanced values corresponding to the peak of diatoms.

EBV-associated leukoencephalopathy with late onset of central nervous system lymphoma in a kidney transplant recipient

Central nervous system (CNS) lymphoma is a rare posttransplant lymphoproliferative disorder (PTLD), which usually has a poor outcome. To date, no specific conditions predisposing to this complication have been identified. We here describe the case of a renal transplant patient who was initially diagnosed as having Epstein-Barr virus (EBV)-associated leukoencephalopathy and ultimately developed EBV-positive CNS lymphoma. The patient was a young lady who, 2 years after transplantation, presented with focal neurological and electroencephalographic abnormalities and diffuse white matter lesions on brain magnetic resonance imaging. EBV-DNA was detected in the cerebrospinal fluid (CSF) by polymerase chain reaction. After acyclovir therapy and immunosuppressive drug tapering, the symptoms and electroencephalographic abnormalities subsided, and EBV-DNA disappeared from the CSF. Ten years later, a bulky cerebral mass was found. After excision, a diagnosis of EBV-positive, Hodgkin-like monomorphic B-cell PTLD was made. This case illustrates the potential pathophysiological relationships between EBV infection, leukoencephalopathy and CNS lymphoma; although a long time elapsed from the initial neurological illness to CNS lymphoma, a link between these two conditions cannot be excluded. Therefore, a careful long-term follow-up of EBV-related encephalopathy is advisable.

Olfactory responses of Trissolcus mitsukurii to plants attacked by target and non-target stink bugs suggest low risk for biological control

In crop systems, successful management of invasive insect herbivores can be achieved through the introduction of exotic biocontrol agents, parasitoids or predators, having a coevolutionary history with the pest. To avert threats to local biodiversity, recent legislations require a risk assessment for the organism to be released. Evaluation of its ability to exploit, for host location, odours associated with target and non-target species is crucial for a better definition of its ecological host range. Using Y-tube olfactometer bioassays in a quarantine laboratory, we investigated the ability of the Asian egg parasitoid Trissolcus mitsukurii (Hymenoptera: Scelionidae) to exploit odours associated with the global invader Halyomorpha halys (Hemiptera: Pentatomidae) and with non-target stink bugs native to Southern Europe. We demonstrated that T. mitsukurii is attracted by plants exposed to feeding and egg deposition of the coevolved H. halys and the native Nezara viridula, while it is not attracted by physogastric (gravid) females or eggs alone. Remarkably, T. mitsukurii is repelled by plants bearing eggs of the beneficial Arma custos. Our results contribute to a more thorough and nuanced assessment of the potential non-target risks in the case of mass-release of parasitoids as part of a biological control programme for invasive stink bugs.

Evaluation of the effect of agroclimatic variables on the probability and timing of olive fruit fly attack

Agroclimatic variables may affect insect and plant phenology, with unpredictable effects on pest populations and crop losses. Bactrocera oleae Rossi (Diptera: Tephritidae) is a specific pest of Olea europaea plants that can cause annual economic losses of more than one billion US dollars in the Mediterranean region. In this study, we aimed at understanding the effect of olive tree phenology and other agroclimatic variables on B. oleae infestation dynamics in the Umbria region (Central Italy). Analyses were carried out on B. oleae infestation data collected in 79 olive groves during a 7-year period (from 2015 to 2021). In July-August, B. oleae infestation (1% attack) was negatively affected by altitude and spring mean daily temperatures and positively by higher winter mean daily temperatures and olive tree cumulative degree days. In September-October, infestation was negatively affected by a positive soil water balance and high spring temperatures. High altitude and cumulative plant degree days were related to delayed attacks. In contrast, high winter and spring temperatures accelerated them. Our results could be helpful for the development of predictive models and for increasing the reliability of decision support systems currently used in olive orchards.

Laboratory and field efficacy of natural products against the invasive pest Halyomorpha halys and side effects on the biocontrol agent Trissolcus japonicus

The brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), is an invasive pest causing major economic losses to crops. Since its outbreaks in North America and Europe, H. halys has been controlled with synthetic pesticides. More sustainable methods have been proposed, including biocontrol and use of natural products. Here, we conducted laboratory and field investigations to evaluate organically registered products for their effectiveness against H. halys and their non-target effect on the egg parasitoid, Trissolcus japonicus (Hymenoptera: Scelionidae). In the laboratory, azadirachtin, orange oil, potassium salts of fatty acids, kaolin, basalt dust, diatomaceous earth, zeolite, sulphur formulations, calcium polysulfide, and mixtures of sulphurs plus diatomaceous earth or zeolite demonstrated higher lethality against H. halys nymphs compared to control. Calcium polysulfide, azadirachtin and sulphur achieved more than 50% mortality. All treatments except azadirachtin and kaolin had negative effects on T. japonicus, with mortality exceeding 80% for calcium polysulfide and sulphur. Field experiments were conducted in 2021 and 2022 in pear orchards. Diatomaceous earth alone or alternated with sulphur or calcium polysulfide provided similar H. halys control, when compared to farm strategies based mostly on neonicotinoid (acetamiprid) treatments. Implications for H. halys control in integrated pest management are discussed.

Effect of microplastics and watering regimes on a plant-soil system: Data on behavioural responses of an insect herbivore

The data presented here are related to the article titled "Microplastics alter behavioural responses of an insect herbivore to a plant-soil system" by Rondoni, G., Chierici, E., Agnelli, A., Conti, E. (2021). The data describe the changes in the attractiveness of a plant-soil system towards females of a herbivorous fungus gnat (Diptera: Sciaridae) when exposed to different combinations of the following treatments: (1) low or high plant (lentil)-soil watering regime; (2) absence (0%) or presence (5%) of HDPE microplastics in soil; (3) 1-day or 7-day duration of HDPE presence; (4) addition of fungus mycelium to the plant-soil system. We report data of female behaviour, i.e. the residence time in choice vs. no-choice sector of one-way olfactometers using a multiple olfactometer device.

Small fibers peroneal mononeuropathy in a patient with Sjögren's syndrome

Sjögren's syndrome (SS) is an autoimmune epithelitis characterized by lymphocytic infiltration of exocrine glands and epithelia in multiple sites. One third of the patients present with peripheral nervous system involvement. We describe the case of a woman aged 62 affected by a peroneal nerve mononeuropathy with painful disturbances secondary to a prevalent involvement of small fibers as demonstrated by electrophysiological investigations and skin biopsy. Asymmetric peripheral nerve involvement is not uncommon in SS, though, to our knowledge, it has never been reported of a mononeuropathy involving primarily small fibers.

Something more to say about calcium homeostasis: the role of vitamin K2 in vascular calcification and osteoporosis

BACKGROUND

Vascular calcification and osteoporosis share similar etiopathogenetic mechanisms. Vitamin K2 deficiency could be responsible of the so called "calcium paradox", that is the lack of calcium in the bone and its storage in the vessel wall. These events may have clinically relevant consequences, such as cardiovascular accidents, and bone fractures.

AIM

To review the biological function of vitamin K2 metabolism, the main factors related to its deficiency and the consequent clinical significance.

DISCUSSION

Vitamin K2 is essential for the function of several proteins, involved in the maintenance of the normal structure of arterial wall, osteoarticular system, teeth, and for the regulation of cell growth. It has been demonstrated to have a pivotal role in the inhibition of vascular foci of calcification, and in the regulation of calcium deposition in the bone. Vitamin K2 deficiency is often subclinic in a large part of healthy population. This deficiency is related to the interaction of various factors, such as the reduced dietary intake, the alteration of intestinal absorption or production, with a possible role of intestinal microbiota and the increased consumption at the vessel wall.

CONCLUSIONS

Vitamin K2 deficiency has recently been recognized as a protagonist in the development of vascular calcification and osteoporosis. Data reported so far are promising and, dietary supplementation seems a useful tool to contrast these diseases. However, large studies or solid clinical correlations regarding vitamin K2 deficiency and its pathologic consequences are needed to confirm these preliminary experiences.

Characterization of Olive Fruit Damage Induced by Invasive Halyomorpha halys

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive species causing economic crop losses. This species was recently detected attacking olive fruits. The aim of this study was to characterize feeding damage. Olive samples were initially collected from a field where H. halys was reported to cause damage to olive fruits. Hence, we conducted a field trial on the Moraiolo variety using sleeve cages to test the effect of H. halys feeding pressure on olive fruit drop and evaluated the effect of feeding on fruit quality. We tested two densities of H. halys (two or eight adults/cage) at two different stages of olive development, pre- and post-pit hardening. High pressure of H. halys before pit hardening caused a significant fruit drop compared to the control. In addition, chemical analysis of damaged and infested fruits revealed higher levels of total phenols compared to healthy fruits. These findings indicate that feeding by H. halys induced a stress response in the plants that could translate in quality variations in the olive drupes.