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International audience; We report on a two-flavour lattice QCD determination of the $B_s\to D_s$ and $B_s\to D_s^*$ transitions, which in the heavy quark limit can be parameterised by the form factors $\mathcal{G}$, and $h_{\text A_1}$, $h_{\text A_2}$ and $h_{\text A_3}$. In the search of New Physics through tests of lepton-flavour universality, $B_s$ decay channels are complementary to $B$ decays and widely studied at $B$ factories and LHCb. The purpose of our study is to explore a suitable method to extract form factors associated with $b\to c$ currents from lattice QCD. In particular, we present numerical results for $\mathcal{G}$ and $h_{\text A_1}$.

Objectives We aimed to investigate the conduction velocity of the cold spinal pathway in healthy humans. Methods Using a cold stimulator consisting of micro-Peltier elements that was able to produce steep cooling ramps up to -300°C/s, we recorded cold-evoked potentials after stimulation of the dorsal midline at C5, T2, T6 and T10 vertebral levels and calculated the conduction velocity of the cold spinal pathway. In all participants, we used laser stimulation to deliver painful heat (Aδ-fibres-mediated) and warm (C-fibres-mediated) stimuli to the same sites in order to compare the conduction velocity of the cold spinal pathway with that of the nociceptive and warm spinal pathways. Results Cold stimulation evoked large-amplitude vertex potentials from all stimulation sites. The mean conduction velocity of the cold spinal pathway was 12.0 m/s, which did not differ from that of the nociceptive spinal pathway (10.5 m/s). The mean conduction velocity of the warm spinal pathway was 2.0 m/s. Discussion This study provides previously unreported findings regarding cold spinal pathway conduction velocity in humans that may be useful in the assessment of spinal cord lesions as well as in intraoperative monitoring during spinal surgery. Significance This neurophysiological study provides previously unreported findings on cold spinal pathway conduction velocity in healthy humans. Cold-evoked potentials may represent an alternative to laser-evoked potential recording, useful to assess spinothalamic tract in patients with spinal cord lesions and monitor patients during spinal surgery.

BACKGROUND In this neurophysiological study, we aimed at verifying the nociceptive selectivity of the new, micropatterned electrode (150IDE), recently designed to generate an electric field limited to the intraepidermal free nerve endings. METHODS Using the new 150IDE, we recorded evoked potentials after stimulation of the face and hand dorsum in 22 healthy participants and in patients with exemplary conditions selectively affecting the nociceptive system. We also measured the peripheral conduction velocity at the upper arm and verified the nociceptive selectivity of 150IDE assessing the effect of a selective block of nociceptive nerve fibres of radial nerve with local anaesthetic infiltration. In healthy participants and in patients, we have also compared the 150IDE-evoked potentials with laser-evoked potentials. RESULTS In healthy participants, the 150IDE-evoked pinprick sensation and reproducible scalp potentials, with latency similar to laser-evoked potentials. The mean peripheral conduction velocity, estimated at the upper arm, was 12 m/s. The selective nociceptive fibre block of the radial nerve abolished the scalp potentials elicited by the 150IDE stimulation. In patients, the 150IDE-evoked potentials reliably detected the selective damage of the nociceptive system. CONCLUSIONS Our neurophysiological study shows that this new 150IDE provides selective information on nociceptive system. SIGNIFICANCE 150IDE is a promising new tool for investigating nociceptive system in patients with neuropathic pain.

We report on a two-flavor lattice QCD study of the Bs→Ds and Bs→Ds* transitions parametrized, in the heavy quark limit, by the form factors G, and hA1, hA2, and hA3, respectively. In the search for New Physics through tests of lepton flavor universality, Bs decay channels are complementary to the B decays widely studied at B factories and LHCb, while on the theory side they can be better controlled than the Bc and Λb decays. The purpose of this exploratory two-flavor study is, in preparation for future analyses of lattice QCD simulations with Nf>2 and physical quark masses, to gain experience on a suitable method for a lattice extraction of form factors associated with b→c currents that may yield tighter control over systematic effects like contamination from excited states and cutoff effects. We obtain the zero-recoil values GBs→Ds(1)=1.03(14) and hBs→Ds*(1)=0.85(16).

We report on a two-flavour lattice QCD study of the $B_s \to D_s$ and $B_s \to D^*_s$ transitions parameterized, in the heavy quark limit, by the form factors ${\cal G}$, and $h_{A_1}$, $h_{A_2}$ and $h_{A_3}$, respectively. In the search for New Physics through tests of lepton flavour universality, $B_s$ decay channels are complementary to the $B$ decays widely studied at $B$ factories and LHCb, while on the theory side they can be better controlled than the $B_c$ and $\Lambda_b$ decays. The purpose of this exploratory two-flavour study is, in preparation for future analyses of lattice QCD simulations with ${N_f>2}$ and physical quark-masses, to gain experience on a suitable method for a lattice extraction of form factors associated with $b \to c$ currents that may yield tighter control over systematic effects like contamination from excited states and cut-off effects. We obtain the zero-recoil values ${\cal G}^{B_s \to D_s}(1)=1.03(14)$ and $h^{B_s \to D^*_s}(1)=0.85(16)$.

BACKGROUND We aimed at evaluating the differential involvement of large myelinated Aβ-, small myelinated Aδ-, and unmyelinated C-fibers in patients with diabetic polyneuropathy and how they contribute to neuropathic pain. METHODS We collected clinical and diagnostic test variables in 133 consecutive patients with diabetic polyneuropathy. All patients underwent Aβ-fiber mediated nerve conduction study, Aδ-fiber mediated laser-evoked potentials and skin biopsy mainly assessing unmyelinated C-fibers. RESULTS Pure large-fiber and small-fiber polyneuropathy were relatively uncommon; conversely mixed-fiber polyneuropathy was the most common type of diabetic polyneuropathy (74%). The frequency of neuropathic pain was similar in the three different polyneuropathies. Ongoing burning pain and dynamic mechanical allodynia were similarly associated with specific small-fiber related variables. CONCLUSIONS Diabetic polyneuropathy mainly manifests as a mixed-fiber polyneuropathy, simultaneously involving Aβ-, Aδ-, and C-fibers. In most patients, neuropathic pain is distinctly associated with small-fiber damage. The evidence that the frequency of neuropathic pain does not differ across pure large-, pure small-, and mixed-fiber polyneuropathy, raises the possibility that in patients with pure large-fiber polyneuropathy nociceptive nerve terminal involvement might be undetected by standard diagnostic techniques.

Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use. Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form. Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results. Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy. Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use. Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form. Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results. Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy.

In human epidermal growth factor receptor 2 (HER2+) expressing breast cancer subtype, the incidence of brain metastases is common and patients often die due to uncontrolled cranial disease. This is a case report of a HER2+ breast cancer woman with diffuse brain metastases that experienced long survival and clinical benefit from multiple radiotherapy treatments and combined systemic therapy, without increased toxicity.