A Novel Heterozygous Variant in AICDA Impairs Ig Class Switching and Somatic Hypermutation in Human B Cells and is Associated with Autosomal Dominant HIGM2 Syndrome.

B cells and their secreted antibodies are fundamental for host-defense against pathogens. The generation of high-affinity class switched antibodies results from both somatic hypermutation (SHM) of the immunoglobulin (Ig) variable region genes of the B-cell receptor and class switch recombination (CSR) which alters the Ig heavy chain constant region. Both of these processes are initiated by the enzyme activation-induced cytidine deaminase (AID), encoded by AICDA. Deleterious variants in AICDA are causal of hyper-IgM syndrome type 2 (HIGM2), a B-cell intrinsic primary immunodeficiency characterised by recurrent infections and low serum IgG and IgA levels. Biallelic variants affecting exons 2, 3 or 4 of AICDA have been identified that impair both CSR and SHM in patients with autosomal recessive HIGM2. Interestingly, B cells from patients with autosomal dominant HIGM2, caused by heterozygous variants (V186X, R190X) located in AICDA exon 5 encoding the nuclear export signal (NES) domain, show abolished CSR but variable SHM. We herein report the immunological and functional phenotype of two related patients presenting with common variable immunodeficiency who were found to have a novel heterozygous variant in AICDA (L189X). This variant led to a truncated AID protein lacking the last 10 amino acids of the NES at the C-terminal domain. Interestingly, patients' B cells carrying the L189X variant exhibited not only greatly impaired CSR but also SHM in vivo, as well as CSR and production of IgG and IgA in vitro. Our findings demonstrate that the NES domain of AID can be essential for SHM, as well as for CSR, thereby refining the correlation between AICDA genotype and SHM phenotype as well as broadening our understanding of the pathophysiology of HIGM disorders.

Palladin isoforms 3 and 4 regulate cancer-associated fibroblast pro-tumor functions in pancreatic ductal adenocarcinoma.

Pancreatic Ductal Adenocarcinoma (PDAC) has a five-year survival under 10%. Treatment is compromised due to a fibrotic-like stromal remodeling process, known as desmoplasia, which limits therapeutic perfusion, supports tumor progression, and establishes an immunosuppressive microenvironment. These processes are driven by cancer-associated fibroblasts (CAFs), functionally activated through transforming growth factor beta1 (TGFß1). CAFs produce a topographically aligned extracellular matrix (ECM) that correlates with reduced overall survival. Paradoxically, ablation of CAF populations results in a more aggressive disease, suggesting CAFs can also restrain PDAC progression. Thus, unraveling the mechanism(s) underlying CAF functions could lead to therapies that reinstate the tumor-suppressive features of the pancreatic stroma. CAF activation involves the f-actin organizing protein palladin. CAFs express two palladin isoforms (iso3 and iso4) which are up-regulated in response to TGFß1. However, the roles of iso3 and iso4 in CAF functions remain elusive. Using a CAF-derived ECM model, we uncovered that iso3/iso4 are required to sustain TGFß1-dependent CAF activation, secrete immunosuppressive cytokines, and produce a pro-tumoral ECM. Findings demonstrate a novel role for CAF palladin and suggest that iso3/iso4 regulate both redundant and specific tumor-supportive desmoplastic functions. This study highlights the therapeutic potential of targeting CAFs to restore fibroblastic anti-tumor activity in the pancreatic microenvironment.

2.5-W, continuous-wave, 629-nm solid-state laser source.

We report an efficient, high-power, cw, 629-nm laser source based on a diode-pumped Nd:YAG laser and a periodically poled lithium niobate (PPLN) frequency converter. This device integrates two separate frequency-conversion steps in a single crystal, taking advantage of the ability to fabricate PPLN with nearly arbitrary grating periods and phase-matching temperatures. This device uses a single PPLN crystal that has two grating regions in series. The first region quasi-phase matches a standard optical parametric oscillator process (1064nm?1540nm +3450nm), and the second region quasi-phase matches a sum-frequency process whereby the pump and the signal light make red light (1064nm+1540nm ?629nm). Using a four-mirror ring cavity, we were able to convert 21% of the 1064-nm pump to 629-nm output, yielding 2.5W of red output with 11.8W of input.

Patient-controlled epidural diamorphine for post-operative pain: verbal rating and visual analogue assessments of pain.

Twenty-two patients were studied while receiving epidural analgesia with diamorphine after major lower abdominal surgery under combined regional and general anaesthesia. Epidural PCA began when the intraoperative epidural block with bupivacaine wore off enough for the patient to request treatment. It was started with 2 mg of diamorphine and continued with a reducible background infusion that was initially set at 0.2 mg h-1 and supplemented by on-demand doses of 0.2 mg, with a lockout time of 15 min. The patients received routine post-operative monitoring and care, with pain at rest being assessed on a four-point verbal rating scale (VRS, none, mild, moderate, severe) at 5, 10, 15, 30, 45, 60, 90 and 120 min from the start of ePCA, then hourly until 24 h and then 2-hourly until 48 h. VRS on coughing and a 10 cm visual analogue score (VAS) at rest and on coughing were recorded at the same times at 4 h, then 4 hourly until 24 h and then at 48 h, at which times, blood samples were also taken to measure morphine concentrations by radioimmunoassay. Analgesia started promptly and reached a maximum at between 30 and 45 min, accompanied by maximum sedation. Thereafter clinically acceptable analgesia was maintained without undue sedation for 48 h, though pain on coughing was less well controlled than pain at rest. After the initial loading dose of diamorphine, the 95% confidence intervals (CI) for further consumption were 3.7 to 17 mg (average 9.7) in the first 24 h and 2.1 to 12.9 mg (average 6.7 mg) in the second 24 h. The plasma morphine concentrations rose to a plateau by about 15 min, with concentrations within 95% CI from 0 to 11 ng mliters-1 (average 5 ng mliters-1. The VRS and VAS pain scores were analysed by a conservative approach that treated them as ordinal data, and by a parametric approach that treated them as interval data. Both approaches conveyed broadly similar information about the post-operative analgesia.

Continuous-wave singly resonant optical parametric oscillator based on periodically poled LiNbO(3).

We report a continuous-wave singly resonant optical parametric oscillator (OPO) based on periodically poled lithium niobate. The simple, two-mirror OPO, pumped by a 1.064-microm Nd:YAG laser, had a 2.6-4.5-W threshold and an output of >1.2 W at 3.3 microm and was tuned over 1.45-1.62 microm (signal) and 3.98-3.11 microm (idler). The noise characteristics and the spectral properties of the device are described.

93% pump depletion, 3.5-W continuous-wave, singly resonant optical parametric oscillator.

We report two cw, singly resonant optical parametric oscillator (OPO) configurations based on periodically poled lithium niobate that result in significantly higher efficiency and output power than in previous studies. Using four-mirror OPO cavities and pumping with a 1.064-microm Nd:YAG laser, we observe 93% pump depletion and obtain ~86% of the converted pump photons as useful idler output. The single-beam, in-the-bucket idler output power of 3.55 W at 3.25 microm corresponds to ~80% of quantum-limited performance. We measure and compare the amplitude noise and spectral bandwidth of the two configurations. We also demonstrate >1 W of tunable cw output over the 3.3-3.9-microm spectral range.

Epidural diamorphine infusions with and without 0.167% bupivacaine for post-operative analgesia.

Forty patients who underwent upper or mid-abdominal surgery were randomly allocated to receive a post-operative epidural infusion of 0.083 mg ml-1 of diamorphine in either 0.167% bupivacaine or 0.9% NaCl solution. The nursing staff, who were unaware of which solution was being infused, managed the patients' pain according to a standardized scheme. They adjusted the epidural infusion rates to 3, 5 or 7 ml h-1 according to the patient's hourly reports of pain on a four point verbal rating scale (none, mild, moderate or severe), aiming to use the lowest allowed infusion rate to prevent or reduce any pain that was more than mild. Additional analgesia was given as diclofenac 75 mg intramuscularly if the patients report moderate pain while on the highest infusion rate. The nurses were instructed to summon anaesthetic help if pain relief was still unsatisfactory after diclofenac, but this was never necessary. Diclofenac was needed by six patients receiving diamorphine in saline and one receiving diamorphine in bupivacaine (P < 0.05). The range of average hourly epidural infusion rates was constrained by design to between 3 and 7 ml h-1 but the median of these values was 5 ml h-1 in the diamorphine-saline group and 3.35 ml h-1 in the diamorphine-bupivacaine group (P < 0.02). In patients receiving diamorphine in saline, a median of 6 (range 0-16) of the 24 h reports were of more than mild pain, whereas in the diamorphine-bupivacaine group, the corresponding figures were 2 (range 0-13) (P < 0.02)).(ABSTRACT TRUNCATED AT 250 WORDS)

Pain after laparoscopy related to posture and ring versus clip sterilization.

In an attempt to reduce pain after laparoscopy, presumed to be due to persistence of CO2 in the peritoneal cavity especially under the diaphragm, women were kept 30 degrees head down for 30 min immediately after operation. By random selection 67 treated patients were compared with 64 kept flat, postoperative symptoms being recorded at fixed times for 3 days. Although tilting was found to be of no significant benefit there were two useful findings. In both groups there was a significant fall in the frequency of upper abdominal pain during the first postoperative night from about 53% to about 25%, followed by a rise after returning home on the first postoperative day to about 60% and only a slow fall in the next 2 days. The severity of pain followed the same pattern. Patients should be warned to expect increased pain on ambulation after leaving hospital. Also, there was doubling in lower abdominal pain during the first 6 h associated with the use of Falope rings for sterilization, compared with either Hulka clip sterilization or only diagnostic laparoscopy.

Abdominal pain after laparoscopy: the value of a gas drain.

In an attempt to reduce pain after laparoscopy, a drain was left for 6 h in the peritoneal cavity through the umbilical incision to take advantage of visceral peristaltic and voluntary muscle movements to expel residual gas. In a randomized study 25 treated patients were compared with 28 controls. Use of the drain was found to approximately halve the frequency of pain throughout the first 2 postoperative days. The severity of pain was also significantly reduced in the first 6 h and after mobilization at home the next day when pain is usually at its worst.

Comparison of buprenorphine-hyoscine and papaveretum-hyoscine as premedicants for gynaecological surgery.

Buprenorphine 0.3 mg and papaveretum 20 mg, both combined with hyoscine 0.4 mg, were used as premedicants in female patients undergoing laparoscopy or abdominal hysterectomy. The effects were compared. It was found that the increase in drowsiness and tranquility was greater following buprenorphine than that following papaveretum. A low frequency of nausea was reported in the buprenorphine-hyoscine group of patients who had undergone hysterectomy. The analgesic effects of the drugs, in these doses, appeared to be similar in degree and duration.

A survey of pain relief clinics in the South Western Region.

All the district general hospitals in the South Western Health Region have a pain relief service in existence or planned for the immediate future. Almost all are recognized by the allocation of anaesthetic consultant sessions. In most cases, this allocation is less than the time required for pain relief. All the consultants concerned work in single disciplinary clinics and accept both in-patient and out-patient referrals. They provide an advisory and therapeutic service to patients in the care of other clinicians and give tuition, mainly to junior anaesthetists. Most also undertake domiciliary assessment and treatment. In most clinics the Pain Relief Service is hampered by inadequate facilities. The minimum facilities for a basic efficient service are here reviewed.