Spectroscopic characterization of the a3Π state of aluminum monofluoride.

Spectroscopic studies of aluminum monofluoride (AlF) have revealed its highly favorable properties for direct laser cooling. All Q lines of the strong A1Π â† X1Σ+ transition around 227 nm are rotationally closed and thereby suitable for the main cooling cycle. The same holds for the narrow, spin-forbidden a3Π â† X1Σ+ transition around 367 nm, which has a recoil limit in the µK range. We here report on the spectroscopic characterization of the lowest rotational levels in the a3Π state of AlF for v = 0-8 using a jet-cooled, pulsed molecular beam. An accidental AC Stark shift is observed on the a3Π0, v = 4 ← X1Σ+, v = 4 band. By using time-delayed ionization for state-selective detection of the molecules in the metastable a3Π state at different points along the molecular beam, the radiative lifetime of the a3Π1, v = 0, J = 1 level is experimentally determined as τ = 1.89 ± 0.15 ms. A laser/radio frequency multiple resonance ionization scheme is employed to determine the hyperfine splittings in the a3Π1, v = 5 level. The experimentally derived hyperfine parameters are compared to the outcome of quantum chemistry calculations. A spectral line with a width of 1.27 kHz is recorded between hyperfine levels in the a3Π, v = 0 state. These measurements benchmark the electronic potential of the a3Π state and yield accurate values for the photon scattering rate and for the elements of the Franck-Condon matrix of the a3Π-X1Σ+ system.

Bedside hyperspectral imaging indicates a microcirculatory sepsis pattern - an observational study.

INTRODUCTION: Microcirculatory alterations are key mechanisms in sepsis pathophysiology leading to tissue hypoxia, edema formation, and organ dysfunction. Hyperspectral imaging (HSI) is an emerging imaging technology that uses tissue-light interactions to evaluate biochemical tissue characteristics including tissue oxygenation, hemoglobin content and water content. Currently, clinical data for HSI technologies in critical ill patients are still limited. METHODS AND ANALYSIS: TIVITA® Tissue System was used to measure Tissue oxygenation (StO2), Tissue Hemoglobin Index (THI), Near Infrared Perfusion Index (NPI) and Tissue Water Index (TWI) in 25 healthy volunteers and 25 septic patients. HSI measurement sites were the palm, the fingertip, and a suprapatellar knee area. Septic patients were evaluated on admission to the ICU (E), 6 h afterwards (E+6) and three times a day (t3-t9) within a total observation period of 72 h. Primary outcome was the correlation of HSI results with daily SOFA-scores. RESULTS: Serial HSI at the three measurement sites in healthy volunteers showed a low mean variance expressing high retest reliability. HSI at E demonstrated significantly lower StO2 and NPI as well as higher TWI at the palm and fingertip in septic patients compared to healthy volunteers. StO2 and TWI showed corresponding results at the suprapatellar knee area. In septic patients, palm and fingertip THI identified survivors (E-t4) and revealed predictivity for 28-day mortality (E). Fingertip StO2 and THI correlated to SOFA-score on day 2. TWI was consistently increased in relation to the TWI range of healthy controls during the observation time. Palm TWI correlated positively with SOFA scores on day 3. DISCUSSION: HSI results in septic patients point to a distinctive microcirculatory pattern indicative of reduced skin oxygenation and perfusion quality combined with increased blood pooling and tissue water content. THI might possess risk-stratification properties and TWI could allow tissue edema evaluation in critically ill patients. CONCLUSION: HSI technologies could open new perspectives in microcirculatory monitoring by visualizing oxygenation and perfusion quality combined with tissue water content in critically ill patients - a prerequisite for future tissue perfusion guided therapy concepts in intensive care medicine.

Imaging cold molecules on a chip.

We present the integrated imaging of cold molecules in a microchip environment. The on-chip detection is based on resonance-enhanced multiphoton ionization, which is quantum state selective and generally applicable. We demonstrate and characterize time-resolved spatial imaging and subsequently use it to analyze the effect of a phase-space manipulation sequence aimed at compressing the velocity distribution of a molecular ensemble with a view to future high-resolution spectroscopic studies. The realization of such on-chip measurements adds the final fundamental component to the molecule chip, offering a new and promising route for investigating cold molecules.

Somatic mutation of the MEN1 gene in parathyroid tumours.

Primary hyperparathyroidism is a common disorder with an annual incidence of approximately 0.5 in 1,000 (ref. 1). In more than 95% of cases, the disease is caused by sporadic parathyroid adenoma or sporadic hyperplasia. Some cases are caused by inherited syndromes, such as multiple endocrine neoplasia type 1 (MEN1; ref. 2). In most cases, the molecular basis of parathyroid neoplasia is unknown. Parathyroid adenomas are usually monoclonal, suggesting that one important step in tumour development is a mutation in a progenitor cell. Approximately 30% of sporadic parathyroid tumours show loss of heterozygosity (LOH) for polymorphic markers on 11q13, the site of the MEN1 tumour suppressor gene. This raises the question of whether such sporadic parathyroid tumours are caused by sequential inactivation of both alleles of the MEN1 gene. We recently cloned the MEN1 gene and identified MEN1 germline mutations in fourteen of fifteen kindreds with familial MEN1 (ref. 10). We have studied parathyroid tumours not associated with MEN1 to determine whether somatic mutations in the MEN1 gene are present. Among 33 tumours we found somatic MEN1 gene mutation in 7, while the corresponding MEN1 germline sequence was normal in each patient. All tumours with MEN1 gene mutation showed LOH on 11q13, making the tumour cells hemi- or homozygous for the mutant allele. Thus, somatic MEN1 gene mutation for the mutant allele. Thus, somatic MEN1 gene mutation contributes to tumorigenesis in a substantial number of parathyroid tumours not associated with the MEN1 syndrome.

HRPT2, encoding parafibromin, is mutated in hyperparathyroidism-jaw tumor syndrome.

We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors.

Localizing the Primary Motor Cortex of the Hand by the 10-5 and 10-20 Systems for Neurostimulation: An MRI Study.

Background. The primary motor cortex of the hand (M1-Hand) is a target used in transcranial magnetic stimulation (TMS) and in transcranial direct current stimulation (tDCS) for the treatment and evaluation of motor neurological diseases. Magnetic resonance imaging-guided neuronavigation locates the M1-Hand with high precision, but at a high cost. Although less accurate, the C3/C4 points of the international 10-20 system (IS 10-20) are routinely used to locate the M1-Hand. The international 10-5 system (IS 10-5) was developed with additional points (C3h/C4h), which could make it more accurate, but has not yet been tested on the location of the M1-Hand. Objective. To analyze and compare the accuracy of C1/C2, C3h/C4h and C3/C4 points in locating the M1-Hand correspondence on the scalp. Methods. The authors comparatively analyzed the distances from points C1/C2, C3h/C4h, and C3/C4 to the correspondence of the M1-Hand on the scalp in 30 MRI head exams. Results. In most cases, the M1-Hand was located between C1-C3h and C2-C4h in the left and right hemispheres of the brain, respectively. The C3h (0.98 ± 0.49 cm) and C4h (0.98 ± 0.51 cm) points presented the shortest distances from the M1-Hand, with a significant difference when compared with C3/C4. The accuracy between C1/C2 and C3h/C4h was not statistically significant. Conclusion. The C3h/C4h and C1/C2 points were more accurate when compared with the C3 and C4 points in locating the M1-Hand correspondence on the scalp.

Microanatomical and immunohistochemical study of the human lateral antebrachial cutaneous nerve of forearm at the antecubital fossa and its clinical implications.

Changes in the intraneural anatomy with age can cause poor prognosis of nerve repair in patients after nerve injury. The occurrence of Complex Regional Pain Syndrome-Type II, secondary to peripheral nerve injury, is common. The purpose of this study is to asses changes in cross-sectional anatomy of the lateral antebrachial cutaneous nerve of forearm (LCNF) at the antecubital fossa in the fascicular, nonfascicular components (adipose and nonadipose tissue), and sympathetic fibers area with respect to age. For the purpose of the study, 32 human (37-88 years) fresh cadaveric LCNF were collected from left-antecubital fossae and processed for histological, morphometric analysis [total cross-sectional (Asc), fascicular (Af), and nonfascicular area (Anonf)], and immunohistochemical method (tyrosine hydroxylase) for sympathetic fibers. The LCNF's average total cross-sectional area was 3.024 mm(2), and fascicular area was 0.582 mm(2). The average number of fascicles per mm(2) was 3.09. The cross-sectional area in the nerve was mainly occupied by nonfascicular connective tissue (80.75%). There was increased adipose tissue deposition (48.48% of Asc) and decreased collagen fibers (32.24% of Asc) in interfascicular domains without any definite relationship with age. The average sympathetic fiber area was 0.026 mm(2) within the nerve fascicular area without any correlation with age. In LCNF, there was more adipose tissue and less collagen fibers deposition in the interfascicular domains of all age cases, and this may act as an obstacle for nerve fiber regeneration on using LCNF as an interpositional nerve graft.

Distribution of sympathetic fiber areas of radial nerve in the forearm: an immunohistochemical study in cadavers.

PURPOSE: Secondary to peripheral nerve injuries, involvement of sympathetic fibers complications such as complex regional pain syndrome (CRPS) have been reported. There are limited studies on the sympathetic fibers and their distribution in the upper limb nerves. There are no reports available in the distribution of the sympathetic fibers/areas of radial nerve in the forearm. The aim of the present study was an attempt to find the distribution of sympathetic fibers in the radial nerve just above cubital fossa (RN), superficial branch of radial nerve at cubital fossa (SBRN-1) and above wrist (SBRN-2). METHODS: We have studied on 19 fresh human cadaveric RN, SBRN-1, and SBRN-2 samples. Frozen sections of these nerves were processed by immunohistochemical (tyrosine hydroxylase) method for sympathetic fibers. RESULTS: The sympathetic fibers area (Asym) was found to be more in RN when compared to SBRN-1 and SBRN-2. The comparison of the sympathetic index (SI = sympathetic fibers area/total fascicular area of the nerve) between RN and SBRN-1 (p < 0.001), RN and SBRN-2 (p < 0.001), and SBRN-1 and SBRN-2 (p = 0.016) were statistically significant. The sympathetic index (SI) for SBRN-1 was more when compared to RN and SBRN-2. CONCLUSIONS: Sympathetic fibers area (Asym) was found to be more in RN when compared to SBRN-1 and SBRN-2. The sympathetic ratio (SI) and percentage of sympathetic fibers area (Asym %) was more in SBRN-1 when compared to RN and SBRN-2. These results of the study might help to explain sympathetic system-related diseases in the area of distribution of RN and SBRN.

Microanatomical and immunohistochemical study of the human anterior branch of the medial antebrachial cutaneous nerve of forearm at the antecubital fossa and its clinical implications.

PURPOSE: Poor prognosis of nerve repair in patients may be due to changes in intraneural anatomy with age. Also, chances of Complex Regional Pain Syndrome-Type I (CRPS-I) secondary to peripheral nerve injury are comparatively high. The present study is to find the fascicular pattern of the anterior branch of the medial antebrachial cutaneous nerve of forearm (MACN) (at antecubital fossa), microanatomic morphometric characteristics of its connective tissue components (adipose tissue) and changes with age and study of intraneural sympathetic fiber content. MATERIAL AND METHODS: Sixty six human (37-88-year-old) cadaveric anterior branch of MACN have been collected from antecubital fossa and the study has been performed at magnifications (5x, 10x, 20x, and 40x objective) after routine histological (Hematoxylin & Eosin stain, Masson's trichrome stain) processing was done for morphometric analysis (total cross-sectional, fascicular and non-fascicular area) and immunohistochemical (tyrosine hydroxylase) processing for sympathetic fibers. RESULTS AND CONCLUSIONS: The anterior branch of the MACN's average total cross section area was 1.150 mm(2) on right side and 1.156 mm(2) on left side. There was significant increase in non-fascicular connective tissue area. In non-fascicular area, there was very less amount of adipose tissue in 86.37% of cases and more adipose tissue in 13.63% (elderly) cases. The average sympathetic fiber area is 0.0109 mm(2) without definite relationship with age. Our study makes an attempt to build a normal data base for MACN which might be helpful during the application of diagnostic and surgical nerve graft procedures.

Histological and ultrasonographical study of the human superficial branch of the radial nerve at distal forearm and its clinical implications.

PURPOSE: Age as poor prognostic factor following nerve repair may be due to change in intraneural anatomy with age. The purpose of this study is to find out the cross sectional microanatomy of the superficial branch of radial nerve (SBRN) at distal part of forearm for changes in the fascicular, non-fascicular components with respect to age and also to find cross section area of SBRN in healthy volunteers. MATERIAL AND METHODS: Sixty fresh human (37-88-year-old) cadaveric SBRN were collected from the distal part of forearm and studied at different magnifications after histological processing for morphometric analysis - total cross-sectional (Asc), fascicular (Af) and non-fascicular area (Anonf). Fifteen volunteers SBRN cross sectional area was measured by ultrasonography (US). RESULTS: The SBRN was found to have 6-12 fascicles. Morphometric and correlation analysis confirmed that there was a significant increase of total cross section area, with significant increase of interfascicular adipose tissue in relation to advancing age. Ultrasonographic cross-sectional area ranged from 2 to 3.3 mm². CONCLUSIONS: Our study revealed comparatively more adipose tissue in human SBRN with advancing age. These findings may help to explain poor prognosis with advancing age following repair. SBRN ultrasonographical Asc was comparable to histological Asc. Further, it is possible to find Asc of SBRN by non-invasive US study and calculate the fascicular and non-fascicular area using our histological findings.

Million-year lag times in a post-orogenic sediment conveyor.

Understanding how sediment transport and storage will delay, attenuate, and even erase the erosional signal of tectonic and climatic forcings has bearing on our ability to read and interpret the geologic record effectively. Here, we estimate sediment transit times in Australia's largest river system, the Murray-Darling basin, by measuring downstream changes in cosmogenic 26Al/10Be/14C ratios in modern river sediment. Results show that the sediments have experienced multiple episodes of burial and reexposure, with cumulative lag times exceeding 1 Ma in the downstream reaches of the Murray and Darling rivers. Combined with low sediment supply rates and old sediment blanketing the landscape, we posit that sediment recycling in the Murray-Darling is an important and ongoing process that will substantially delay and alter signals of external environmental forcing transmitted from the sediment's hinterland.

Comment on: "A novel approach to peatlands as archives of total cumulative spatial pollution loads from atmospheric deposition of airborne elements complementary to EMEP data: Priority pollutants (Pb, Cd, Hg)" by Ewa Miszczak, Sebastian Stefaniak, Adam Michczynski, Eiliv Steinnes and Irena Twardowska.

A recent paper by Miszczak et al. (2020) examines metal contamination of mires in Poland and Norway. The authors conclude that lead (Pb) records in ombrotrophic peatlands cannot be used to reconstruct the chronological history of anthropogenic activities due to post-depositional mobility of the metal. We contest this general conclusion which stands in contrast with a significant body of literature demonstrating that Pb is largely immobile in the vast majority of ombrotrophic peatlands. Our aim is to reaffirm the crucial contribution that peat records have made to our knowledge of atmospheric Pb contamination. In addition, we reiterate the necessity of following established protocols to produce reliable records of anthropogenic Pb contamination in environmental archives.

Diagnosis of asymptomatic primary hyperparathyroidism: proceedings of the third international workshop.

OBJECTIVE: Asymptomatic primary hyperparathyroidism (PHPT) is a common clinical problem. The purpose of this report is to guide the use of diagnostic tests for this condition in clinical practice. PARTICIPANTS: Interested professional societies selected a representative for the consensus committee and provided funding for a one-day meeting. A subgroup of this committee set the program and developed key questions for review. Consensus was established at a closed meeting that followed. The conclusions were then circulated to the participating professional societies. EVIDENCE: Each question was addressed by a relevant literature search (on PubMed), and the data were presented for discussion at the group meeting. CONSENSUS PROCESS: Consensus was achieved by a group meeting. Statements were prepared by all authors, with comments relating to accuracy from the diagnosis subgroup and by representatives from the participating professional societies. CONCLUSIONS: We conclude that: 1) reference ranges should be established for serum PTH in vitamin D-replete healthy individuals; 2) second- and third-generation PTH assays are both helpful in the diagnosis of PHPT; 3) DNA sequence testing can be useful in familial hyperparathyroidism or hypercalcemia; 4) normocalcemic PHPT is a variant of the more common presentation of PHPT with hypercalcemia; 5) serum 25-hydroxyvitamin D levels should be measured and, if vitamin D insufficiency is present, it should be treated as part of any management course; and 6) the estimated glomerular filtration rate should be used to determine the level of kidney function in PHPT: an estimated glomerular filtration rate of less than 60 ml/min.1.73 m2 should be a benchmark for decisions about surgery in established asymptomatic PHPT.

Immunocytology with microwave-fixed fibroblasts shows 1 alpha,25-dihydroxyvitamin D3-dependent rapid and estrogen-dependent slow reorganization of vitamin D receptors.

Prior studies have given no evidence for regulation of vitamin D receptor (VDR) compartmentalization or subcellular organization. Microwave fixation (9-15 s) and an indirect immunodetection system of avidin-biotin enhancement and phycoerythrin fluorophore resulted in sufficient spatial and temporal resolution to allow analysis of these processes. We studied cultured fibroblasts from normals or from patients with four different types of hereditary defect compromising VDR function (mutant cells). Compartmentalization of VDRs in the absence of 1,25-dihydroxyvitamin D3 (calcitriol) was regulated by serum or estrogen. VDRs were mainly cytoplasmic in cells cultured without serum and phenol red, but VDRs were mainly intranuclear after addition of serum or an estrogen to cells for at least 18 h (slow regulation). Calcitriol initiated a rapid and multistep process (rapid regulation) of reorganization in a portion of VDRs: clumping within 15-45 s, alignment of clumps along fibrils within 30-45 s, perinuclear accumulation of clumps within 45-90 s, and intranuclear accumulation of clumps within 1-3 min. We found similar rapid effects of calcitriol on VDRs in various other types of cultured cells. These sequential VDR pattern changes showed calcitriol dose dependency and calcitriol analogue specificity characteristic for the VDR. In mutant fibroblasts VDR pattern changes after calcitriol were absent or severely disturbed at selected steps. Treatment of normal cells with wheat germ agglutinin, which blocks protein transport through nuclear pores, also blocked calcitriol-dependent translocation of VDRs. We conclude that immunocytology after microwave fixation provides evidence for regulation of VDR organization and localization.

Phosphorylation-dependent regulation of ryanodine receptors: a novel role for leucine/isoleucine zippers.

Ryanodine receptors (RyRs), intracellular calcium release channels required for cardiac and skeletal muscle contraction, are macromolecular complexes that include kinases and phosphatases. Phosphorylation/dephosphorylation plays a key role in regulating the function of many ion channels, including RyRs. However, the mechanism by which kinases and phosphatases are targeted to ion channels is not well understood. We have identified a novel mechanism involved in the formation of ion channel macromolecular complexes: kinase and phosphatase targeting proteins binding to ion channels via leucine/isoleucine zipper (LZ) motifs. Activation of kinases and phosphatases bound to RyR2 via LZs regulates phosphorylation of the channel, and disruption of kinase binding via LZ motifs prevents phosphorylation of RyR2. Elucidation of this new role for LZs in ion channel macromolecular complexes now permits: (a) rapid mapping of kinase and phosphatase targeting protein binding sites on ion channels; (b) predicting which kinases and phosphatases are likely to regulate a given ion channel; (c) rapid identification of novel kinase and phosphatase targeting proteins; and (d) tools for dissecting the role of kinases and phosphatases as modulators of ion channel function.

Coupled gating between individual skeletal muscle Ca2+ release channels (ryanodine receptors)

Excitation-contraction coupling in skeletal muscle requires the release of intracellular calcium ions (Ca2+) through ryanodine receptor (RyR1) channels in the sarcoplasmic reticulum. Half of the RyR1 channels are activated by voltage-dependent Ca2+ channels in the plasma membrane. In planar lipid bilayers, RyR1 channels exhibited simultaneous openings and closings, termed "coupled gating." Addition of the channel accessory protein FKBP12 induced coupled gating, and removal of FKBP12 uncoupled channels. Coupled gating provides a mechanism by which RyR1 channels that are not associated with voltage-dependent Ca2+ channels can be regulated.

Calcitonin receptors of kidney and bone.

Receptors for calcitonin, determined by activation of adenylate cyclase, were found in a distribution among zones of the kidney distinct from that of receptors for parathyroid hormone or vasopressin. Competitive binding studies showed that the receptors for calcitonin are similar in kidney and bone and that their high apparent affinity for salmon calcitonin accounts in part for the high biological potency in vivo of salmon calcitonin.

Vitamin D3--resistant fibroblasts have immunoassayable 1,25-dihydroxyvitamin D3 receptors.

Cultured fibroblasts obtained from patients with tissue resistance to 1,25-dihydroxyvitamin D3 (vitamin D3--dependent rickets, type II) contain normal, low, or undetectable concentrations of this hormone's receptor protein as measured by a ligand-binding assay. Extracts from these cells were evaluated for receptors by immunoassay with a recently developed monoclonal antibody to the chick receptor. The results show that a protein sedimenting at 3.7S and recognizable by the antibody exists in comparable concentrations in cells from both normal and resistant patients, irrespective of the hormone-binding abnormalities of the cells. This implies that deficiencies in hormone binding associated with inherited tissue resistance to 1,25-dihydroxyvitamin D3 probably arise from structural variations in the receptor molecule and not from defective receptor synthesis.

Positional cloning of the gene for multiple endocrine neoplasia-type 1.

Multiple endocrine neoplasia-type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by tumors in parathyroids, enteropancreatic endocrine tissues, and the anterior pituitary. DNA sequencing from a previously identified minimal interval on chromosome 11q13 identified several candidate genes, one of which contained 12 different frameshift, nonsense, missense, and in-frame deletion mutations in 14 probands from 15 families. The MEN1 gene contains 10 exons and encodes a ubiquitously expressed 2.8-kilobase transcript. The predicted 610-amino acid protein product, termed menin, exhibits no apparent similarities to any previously known proteins. The identification of MEN1 will enable improved understanding of the mechanism of endocrine tumorigenesis and should facilitate early diagnosis.

Unusual features of the c-ring of F1FO ATP synthases.

Membrane integral ATP synthases produce adenosine triphosphate, the universal "energy currency" of most organisms. However, important details of proton driven energy conversion are still unknown. We present the first high-resolution structure (2.3 Å) of the in meso crystallized c-ring of 14 subunits from spinach chloroplasts. The structure reveals molecular mechanisms of intersubunit contacts in the c14-ring, and it shows additional electron densities inside the c-ring which form circles parallel to the membrane plane. Similar densities were found in all known high-resolution structures of c-rings of F1FO ATP synthases from archaea and bacteria to eukaryotes. The densities might originate from isoprenoid quinones (such as coenzyme Q in mitochondria and plastoquinone in chloroplasts) that is consistent with differential UV-Vis spectroscopy of the c-ring samples, unusually large distance between polar/apolar interfaces inside the c-ring and universality among different species. Although additional experiments are required to verify this hypothesis, coenzyme Q and its analogues known as electron carriers of bioenergetic chains may be universal cofactors of ATP synthases, stabilizing c-ring and prevent ion leakage through it.