Loss of calcineurin in the spinal dorsal horn contributes to neuropathic pain,and intrathecal administration of the phosphatase provides prolonged analgesia

Calcineurin (protein phosphatase 3) regulates synaptic plasticity in the brain. The development of neuropathic pain appears dependent on some of the same mechanisms that underlie brain synaptic plasticity. In this study, we examined whether calcineurin regulates chronic constriction injury (CCI)-elicited plasticity in the spinal dorsal horn. CCI animals exhibited mechanical and thermal hypersensitivity 7 days after ligation of the sciatic nerve. Neither control uninjured nor sham-operated animals exhibited pain behavior. Calcineurin activity and content of its Aα isoform were significantly decreased in the ipsilateral postsynaptic density (PSD) of dorsal horn neurons in CCI animals. Calcineurin activity and content in the contralateral PSD of CCI animals or either side of the dorsal horn in sham animals were not modified. The pain behavior in CCI animals was attenuated by intrathecal application of exogenous calcineurin. The treatment was long-lasting as a single injection provided analgesia for 4 days by restoring the phosphatase’s activity and Aα content in the PSD. No signs of toxicity were detected up to 14 days after the single intrathecal injection. Intrathecal application of the calcineurin inhibitor FK-506 elicited pain behavior in control uninjured animals and significantly reduced calcineurin activity in the PSD. CCI may elicit neuropathic pain at least in part as a result of the loss of calcineurin-mediated dephosphorylation in the dorsal horn. Addition of the phosphatase by intrathecal injection reverses the injury-elicited loss and provides prolonged pain relief. Clinical therapy with calcineurin may prove to be a novel, effective, and safe approach in the management of well-established neuropathic pain.     

Both TLR2 and TLR4 are required for the effective immune response in Staphylococcus aureus-induced experimental murine brain abscess

Toll-like receptors (TLRs) play central roles in the innate reaction to bacterial products and transmit specific immune responses against these pathogens. TLRs are expressed on numerous cell types, including innate immune cells, and on astrocytes, neurons, and microglial cells of the central nervous system (CNS). Lipoproteins and lipopolysaccharides are specifically recognized by TLR2 and TLR4, respectively. We examined the in vivo role of TLR2 and TLR4 in Staphylococcus aureus-induced brain abscess. Phenotypically, 87% of TLR2(-/-) mice and 43% of TLR4(-/-) mice died whereas all wild-type (WT) mice recovered. Clearance of bacteria from the CNS was significantly delayed in TLR2(-/-) mice compared with TLR4(-/-) and WT animals. Recruitment of granulocytes and macrophages to the CNS, as well as microglial activation and expansion, was up-regulated in TLR2(-/-) mice. Although inflammation persisted especially in the CNS of TLR2(-/-) mice, but also of TLR4(-/-) mice, WT mice terminated the infection more effectively. Collectively, these data show that the immune response to experimental S. aureus-induced brain abscess depends crucially on the recognition of S. aureus by TLR2 but that TLR4 is also required for an optimal intracerebral immune response in this disorder.     

The relationship between urinary calcium, sodium, and potassium excretion and the role of potassium in treating idiopathic hypercalciuria

OBJECTIVES: 1) To evaluate the relationships between urinary sodium (UNa), potassium (UK), and calcium (UCa) excretion in the pediatric population; and 2) to determine the effect of increasing potassium intake in patients with idiopathic hypercalciuria and investigate whether this intervention can be offered as another mode of therapy in this patient population. DESIGN: Prospectively, we determined UNa, UK, UCa, and creatinine (Cr) concentrations in randomly collected urine samples from children on initial evaluation for urinary frequency, dysuria, hematuria, enuresis, or kidney stones to identify children with hypercalciuria. SETTING: The outpatient renal clinic of an academic hospital. PARTICIPANTS: Twenty-three black children (13 girls and 10 boys) and 77 white children (44 girls and 33 boys) 3.92 to 16.67 years of age. INTERVENTIONS: Eleven children with hypercalciuria were given potassium supplementation or placed on a high-potassium diet for at least 2 weeks. OUTCOME MEASURES: UNa to UK, UNa to Cr, UK to Cr, and UCa to Cr ratios were calculated from measured levels of urinary minerals. These were repeated in 11 hypercalciuric patients after 2 weeks of increased potassium intake. RESULTS: A total of 100 urine samples were analyzed. The UCa/Cr ratio in blacks 0.04 +/- 0.06 (mean +/- standard deviation) was significantly lower than in whites 0.16 +/- 0.12. There were 21 hypercalciuric white children versus only 1 black child. Linear regression analysis revealed a positive direct correlation between UNa/Cr and UCa/Cr in all 100 subjects and in whites alone but not in blacks. An inverse relationship existed between UK/Cr and UCa/Cr in all subjects and in whites and showed a strong trend in blacks. A marked direct relationship was found between UNa/K and UCa/Cr in all subjects (r = .43) as well as in whites (r = .59) and blacks (r = .49). One black child and 10 white hypercalciuric children were treated with "extra" K for at least 2 weeks. The UNa/K decreased from 4.73 +/- 2.28 to 1.98 +/- 1.09, and the UCa/Cr decreased from 0. 31 +/- 0.10 to 0.14 +/- 0.07, with resolution or improvement of the patients' symptoms. CONCLUSIONS: In our patient population with urinary symptoms, the UCa/Cr ratio in black children is lower and hypercalciuria less common than in white children. In both white and black populations, the UNa/K ratio had the strongest association with the UCa/Cr ratio, indicating an opposing role of UNa and UK on the UCa/Cr ratio. Increased potassium intake was found to be beneficial for hypercalciuric children by decreasing the UNa/K ratio and, consequently, the UCa/Cr ratio.     

L一粘附素单抗在缺血再灌注损伤中的作用

目的：中性粒细胞粘附在缺血再灌注损伤中有非常重要的作用。本文用ＳＤ大鼠趾长屈肌缺血再灌注损伤模型,观察Ｌ一粘附素单抗ＬＡＭ１—１１６在缺血再灌注损伤中的作用。方法：３０只ＳＤ大鼠被均分为２组：ＬＡＭ１—１１６组和生理盐水对照组。每只大鼠的一侧趾长屈肌作为正常对照,另外一侧进行 ３ ｈ缺血 ４ ｈ再灌注。结果：ＬＡＭ１— １１６组实验侧的髓过氧化物酶为正常的２倍（２．３±２．２）,生理盐水对照组则为正常的２８倍（２７．５±１１．７）（Ｐ＜０．００１）;ＬＡＭ１—１１６组的湿重比（１．１０± ０．１０）、疲劳肌力（７７． １％±１２．１％）与对照组相比（分别为 １． ２３± ０． １０和 ４９． ７％± ９ ．３％）明显改善（Ｐ＜ ０．０５）;组织学上,ＬＡＭ１—１１６组的中性粒细胞局部浸润显著减少,水肿减轻。结论：通过 Ｌ－粘附素单克隆抗体 ＬＡＭ１— １１６阻断 Ｌ－粘附素的功能,可以有效地降低中性粒细胞在再灌注肌肉中的浸润,防止组织水肿,从而改善肌肉的功能。     

The Emergence of SARS-CoV-2 within the Dog Population in Croatia: Host Factors and Clinical Outcome

Over a year into the COVID-19 pandemic, there is growing evidence that SARS-CoV-2 infections among dogs are more common than previously thought. In this study, the prevalence of SARS-CoV-2 antibodies was investigated in two dog populations. The first group was comprised of 1069 dogs admitted to the Veterinary Teaching Hospital for any given reason. The second group included dogs that shared households with confirmed COVID-19 cases in humans. This study group numbered 78 dogs. In COVID-19 infected households, 43.9% tested ELISA positive, and neutralising antibodies were detected in 25.64% of dogs. Those data are comparable with the secondary attack rate in the human population. With 14.69% of dogs in the general population testing ELISA positive, there was a surge of SARS-CoV-2 infections within the dog population amid the second wave of the pandemic. Noticeably seroprevalence of SARS-CoV-2 in the dog and the human population did not differ at the end of the study period. Male sex, breed and age were identified as significant risk factors. This study gives strong evidence that while acute dog infections are mostly asymptomatic, they can pose a significant risk to dog health. Due to the retrospective nature of this study, samples for viral isolation and PCR were unavailable. Still, seropositive dogs had a 1.97 times greater risk for developing central nervous symptoms.     

Comparison of different root canal sealers: cytotoxicity and the type of induced cell death

Summary  The aim of this study was to compare in vitro cytotoxicity and determine the type of cell death induced by Hermetic, Diaket, GuttaFlow, Epiphany, SuperEBA and IRM using human laryngeal carcinoma HEp2 cells as the model system. The cytotoxicity was determined by counting the total number of cells by electronic counter, while the number of viable cells was estimated under a light microscope. The number of apoptotic or necrotic cells was estimated under a fluorescent microscope according to their characteristic morphology and staining with specific fluorescent dyes. The results show that GuttaFlow was biocompatible, hardly reducing the number of living human laryngeal carcinoma HEp2 cells through all research periods (except after one month period). On the contrary, Diaket, Epiphany, IRM, Hermetic, and Super EBA exhibited strong toxicity. Diaket and IRM mostly induced apoptosis while for Epiphany, Hermetic and Super EBA, necrosis was the predominant or only type of cell death.      

Survey of Croatian dentists' restorative treatment decisions on approximal caries lesions

Aim

To assess Croatian dentists’ restorative treatment decisions on approximal caries lesions, including treatment threshold and restorative methods and materials.

Methods

Croatian translation of the questionnaire assessing restorative treatment decisions on approximal caries, previously validated and used in Norway and Sweden, was distributed to a random sample (n = 800) of Croatian dentists. A total of 307 (38%) dentists answered the questionnaire. The assessed variables were treatment threshold for hypothetical approximal caries lesion and the most favored types of restorative techniques and materials.

Results

A third of the respondents (39%, 95% confidence interval [CI], 34-44%) would intervene for an approximal caries lesion at the dentin-enamel junction, but a larger proportion (42%; 95% CI, 36-48%) would treat a caries lesion confined to the enamel. For restoration of approximal caries, the majority (66%; 95% CI, 61-71%) would use composite resin.

Conclusion

Croatian dentists tend to restore approximal caries lesions when the lesions are confined to the enamel and their development can still be arrested.Caries diagnosis remains a major challenge in dentistry. Since clinical pattern of caries in industrialized countries is changing and a growing proportion of caries shows slow progression and late cavitation (1), there is an increased risk of hidden approximal caries, ie, the caries that can progress beneath sound enamel surface. In this type of caries, visual examination alone is often insufficient (2) and the use of bitewing radiographs is required (3,4,5). Besides clinical and radiographic findings, the dentist''s decision on restorative threshold and restorative techniques and materials is influenced by patient’s characteristics such as age (6), dental hygiene, dietary habits, and fluoride uptake. Better understanding of demineralization and remineralization of caries lesions and availability of products for mineralization of caries lesions confined to the enamel have resulted in new minimally invasive approaches in restorative dentistry. These approaches can preserve healthy hard dental tissues and therefore should be used in preference to operative treatments indicated when the caries lesion has reached the dentin-enamel junction or cavitation stage (7). However, it is unclear to what extent these approaches have been adopted in Croatia. In addition to variations in materials and techniques, dentists in different countries differ in how well they detect approximal caries lesions (8) and how they plan treatment (9-19). Since dentists'' preferences for restorative treatment are often difficult to be directly inferred from patient files, anonymous questionnaire is used. For example, studies from Norway and Sweden (9,15) that used an anonymous questionnaire showed a relationship between dentists'' preferences for restorative treatment and their age and type of practice.To assess variations among Croatian dentists in the treatment threshold and restorative methods and materials, a pilot study using the survey from Sweden (15) was conducted among Croatian dentists in Split-Dalmatia county (20). The study found that dentists tended to restore caries lesions when the approximal lesion had reached the dentin-enamel junction or had just penetrated the dentin, and that they preferred to use tunnel preparation and composite resin material (20). The present study was designed as an extension of the pilot study and included more dentists, from all parts of Croatia.