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Background and aimsLiving root tissues significantly constrain plant water uptake under drought, but we lack functional traits to feasibly screen diverse plants for variation in the drought responses of these tissues. Water stress causes roots to lose volume and turgor, which are crucial to root structure, hydraulics and growth. Thus, we hypothesized that root pressure-volume (p-v) curve traits, which quantify the effects of water potential on bulk root turgor and volume, would capture differences in rootstock drought tolerance.MethodsWe used a greenhouse experiment to evaluate relationships between root p-v curve traits and gas exchange, whole-plant hydraulic conductance and biomass under drought for eight grapevine rootstocks that varied widely in drought performance in field trials (101-14, 110R, 420A, 5C, 140-Ru, 1103P, Ramsey and Riparia Gloire), grafted to the same scion variety (Vitis vinifera 'Chardonnay').Key resultsThe traits varied significantly across rootstocks, and droughted vines significantly reduced root turgor loss point (πtlp), osmotic potential at full hydration (πo) and capacitance (C), indicating that roots became less susceptible to turgor loss and volumetric shrinkage. Rootstocks that retained a greater root volume (i.e. a lower C) also maintained more gas exchange under drought. The rootstocks that previous field trials have classified as drought tolerant exhibited significantly lower πtlp, πo and C values in well-watered conditions, but significantly higher πo and πtlp values under water stress, than the varieties classified as drought sensitive.ConclusionsThese findings suggest that acclimation in root p-v curve traits improves gas exchange in persistently dry conditions, potentially through impacts on root hydraulics or root to shoot chemical signalling. However, retaining turgor and volume in previously unstressed roots, as these roots deplete wet soil to moderately negative water potentials, could be more important to drought performance in the deep, highly heterogenous rooting zones which grapevines develop under field conditions.

We have previously reported that low doses of external beam ionizing irradiation reduced amyloid-β (Aβ) plaques and improved cognition in APP/PS1 mice. In this study we investigated the effects of radiation in an age-matched series of 3xTg-AD mice. Mice were hemibrain-irradiated with 5 fractions of 2 Gy and sacrificed 8 weeks after the end of treatment. Aβ and tau were assessed using immunohistochemistry and quantified using image analysis with Definiens Tissue Studio. We observed a significant reduction in Aβ plaque burden and tau staining; these two parameters were significantly correlated. This preliminary data is further support that low doses of radiation may be beneficial in Alzheimer's disease.

In the retina, somatostatin (SRIF) acts as a neuromodulator by interacting with specific SRIF subtype (sst) receptors. Aim of this investigation was to determine the cellular localization of the sst2A receptor isoform in the postnatal rabbit retina. Receptor immunoreactivity was localized using the antiserum K-230, directed to the C-terminus of the human sst2A receptor. In the postnatal rabbit retina, sst2A receptors were abundantly expressed without significant regional differences. They were localized predominantly to rod bipolar cells, identified with a protein kinase C (PKC) antibody, to amacrine cells, some of which also containing tyrosine hydroxylase (TH), and to presumed rare horizontal cells. Quantitative analysis showed that sst2A-immunoreactive (-IR) bipolar and amacrine cells reached their maximum density and absolute number at the time of eye opening, when the expression pattern of sst2A receptors was similar to that in adult retinas. In the adult retina, 68% of the PKC-IR rod bipolars and 34% of the TH-IR amacrine cells were observed to also express sst2A receptors. The appearance of sst2A receptor immunolabeling prior to eye opening and the developmental profile of sst2A receptor expression are compatible with a role of SRIF in the maturation of retinal circuitries. The partial expression of sst2A receptors in PKC-IR rod bipolar cells and in TH-IR amacrine cells may suggest some type of heterogeneity within these cell populations.

Purpose: To detect mRNAs for somatostatin (somatotropin release-inhibiting factor [SRIF]) receptor subtypes 1 to 5 (sst(1) through sst(5)) in rabbit retinas by reverse transcription-polymerase chain reaction (RT-PCR) and to investigate the distribution of sst(1) by single- and double-label immunocytochemistry., Methods: Semiquantitative RT-PCR using sst-specific primers from mouse sequences was performed. sst(1) was localized using a polyclonal antiserum directed to human sst(1) in cryostat sections of retinas from either normal or optic nerve-transected animals. Immunolabeled cell sizes and densities were measured in wholemounted retinas using computer-assisted image analysis. Double-label immunofluorescence was performed using the sst(1) antiserum in conjunction with monoclonal antibodies directed to SRIF, tyrosine hydroxylase (TH), parvalbumin (PV), or gamma-aminobutyric acid (GABA)., Results: With RT-PCR it was found that all five sst mRNAs were expressed in the rabbit retina, with highest levels of sst(1) mRNA. sst(1) immunolabeling was localized to amacrine cells in the proximal inner nuclear layer (INL) of all retinal regions and to displaced amacrine cells in the ganglion cell layer (GCL) of the ventral retina. Some large sst(1)-immunoreactive (IR) somata were also present in the GCL. They were not observed after optic nerve transection. Double-label immunofluorescence showed sst(1) expression by all TH-IR amacrine cells and by other amacrine cells that were neither PV-IR nor GABA-IR. In addition, sst(1) was expressed by all SRIF-containing displaced amacrine cells., Conclusions: All five sst mRNAs are expressed in the rabbit retina. The localization of sst(1) suggests that it may mediate SRIF actions onto amacrine (including dopaminergic) and sparse ganglion cells. sst(1) expression in SRIF-IR cells suggests that this receptor may also act as an autoreceptor.

The authors report a rare case of recurrence of lumbar nerve root compression caused by herniated intradiscal gas treated surgically with resolution of pain symptoms. They describe the possible causes of the formation of gaseous material reported in the literature. They believe that to avoid recurrence it is important to associated removal of the hernia with complete emptying of the disc and resection of the posterior longitudinal ligament.

Snapping hip is a polymorphous pathology the genesis of which is multifactorial, characterized by a snapping sensation which may be painful, and occurring during movement of the hip or during walking. Clinical and instrumental diagnosis for an accurate etiopathogenetic classification is essential to correct surgical treatment, that must be reserved only for cases with painful symptoms and with disorders in walking. The authors provide a classification system of the syndrome, describing four different varieties of the pathology and relative surgical treatment.

The authors describe the surgical method used and present the preliminary results obtained in 29 patients affected with recurrent anterior dislocation of the shoulder treated by Neer capsuloplasty and Statak screws. The long-term results were evaluated based on the Rowe system: the score was excellent in 18 cases, good in 2, fair in 4, and poor in 5. All of the patients resumed work activity, with no restrictions, within 4 months of the onset of functional rehabilitation. The use of Statak screws allows us to simplify surgery, while guaranteeing repair of the Bankart lesion, when present. The method reported permits correction of instability, without excessive reduction of joint movement.

The authors present an original solution for distal screw fixation in locked nail intramedullary osteosynthesis, traditionally carried out with image intensifier. The system includes the determination of an electromagnetic field produced by a microbobbin placed in the hole and, thus, coaxial with it. The study, conducted through a probe equipped with special magnet-resistant sensors capable of picking up electromagnetic variations, is based on the same principle as a compass. In addition to being effective and simple, the method avoids exposure to ionizing radiations required for the search for holes.