Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Anatomical variations in the first dorsal compartment of the wrist: meta-analysis

BACKGROUND

The first dorsal compartment of the wrist includes tendons of abductor pollicis longus (APL) and extensor pollicis brevis (EPB). However, many studies have showed multiple anatomical variations including anomalies in the number of both APL and EPB tendons and presence of intercompartmental fibro-osseous septum. Unfortunately, studies describing those variations are not consistent, hence, the aim of this study was to provide most accurate data about these anatomical variations in the population, using systematic review and meta-analysis.

MATERIALS AND METHODS

For this purpose, PubMed, Scopus, Web of Science, Embase and a number of minor online libraries were searched. Articles which included exact data about the number of APL or EPB tendons or a presence of intercompartmental septum were qualified for a more precise evaluation. Therefore, out of 1629 studies initially evaluated, 68 were finally included in this meta-analysis. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 5229 studied wrists have been included in this study. Double APL and single EPB are the most common variations of tendons in the first dorsal compartment, both in cadavers and patients with de Quervain's disease, with no statistically significant differences between those two groups. Presence of intercompartmental fibro-osseus septum is much more common in patients with de Quervain's disease than in cadavers.

CONCLUSIONS

Our results should improve the awareness of anatomical variations in the first dorsal compartment, which in turn should have impact on treatment of de Quervain's disease in clinical practice.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Variations in extra-hepatic biliary tree morphology and morphometry: a narrative review of literature with focus on cystohepatic triangle

The morphometry and morphology of the components of extrahepatic biliary tree show extensive variations. A beforehand recognition of these variations is very crucial to prevent unintended complications while performing surgeries in this region. This study was conducted to analyse the configuration of the extrahepatic biliary tree and its possible variations, as well as measure the components that limit the cystohepatic triangle. Articles were searched in major online indexed databases (Medline and PubMed, Scopus, Embase, CINAHL Plus, Web of Science and Google Scholar) using relevant key words. A total of 73 articles matched the search criteria of which 55 articles were identified for data extraction. The length of left and right hepatic duct in majority of studies was found to be > 10 mm. A wide range of diameters of hepatic ducts were observed between 5 and 43 mm. The average length of cystic duct is around 20 mm. The length and diameter of the common bile duct are 50-150 mm and 3-9 mm, respectively. The most frequently observed pattern of insertion of cystic duct into common hepatic duct is right lateral, rarely anterior, or posterior spiral insertion can present. The results of this study will provide a standard reference range which instead will help to differentiate the normal and pathological conditions.

Carpal tunnel syndrome: state-of-the-art review

Carpal tunnel syndrome is the most common peripheral nerve entrapment encountered worldwide. The aetiology can be related to repetitive exposure to vibrations or forceful angular motions, genetic predisposition, injury and specific conditions, such as diabetes, pregnancy and morbid obesity. This entity is observed with increased frequency in females and the elderly. The diagnosis is largely clinical and suspected when patients present with typical symptoms such as numbness, tingling, nocturnal paraesthesia and/or neuritic "pins-and-needles" pain in the radial 3.5 digits. Certain provocative manoeuvres can be employed to evoke the symptoms of the disease to guide the diagnosis. Further testing such as electrodiagnostic studies, ultrasound or magnetic resonance imaging is required in the case of diagnostic uncertainty or if there is a need for objective evaluation whether or not more invasive surgical intervention is required. If the presenting symptoms are mild and discontinuous, non-surgical measures are indicated. However, if the symptoms are moderate to severe, further testing modalities such as nerve conduction studies or needle electromyography are used to determine whether carpal tunnel syndrome is acute or chronic. If significant evidence of axonal injury is identified, surgical treatment may be indicated. Surgical release of the carpal tunnel has evolved over time to become the most common hand surgery procedure.

Unusual variations in the branching pattern of the coeliac trunk and their clinical significance

BACKGROUND

The anatomical variations of the coeliac trunk are due to developmental changes in the ventral segmental arteries. Multidetector computed tomography (MDCT) has been used to investigate vascular anatomy for scientific and diagnostic purposes. These studies allow for much larger sample sizes than traditional cadaveric studies. The aim of this research was to isolate rare anatomical variants of the coeliac trunk and emphasize their clinical significance.

MATERIALS AND METHODS

A descriptive, retrospective study was carried out on MDCT angiographies performed from January 2020 till March 2020 in Polish patients. Coeliac trunk was studied and normal and anatomical variations were identified.

RESULTS

Out of total 350 patients, hepatogastrosplenic trunk was predominant. However, we observed: coeliaco-mesenteric and hepatogastric trunk type, hepatic artery variations and coeliac axis stenosis with collateral mesenteric circulation.

CONCLUSIONS

Rare variations of the coeliac trunk should always be anticipated before radiological and surgical interventions. Knowledge of unusual coeliac trunk anatomy is important in hepatopancreatobiliary surgery, transplantology, and interventional radiology.

Rare combined variations of the coeliac trunk, accessory hepatic and gastric arteries with co-occurrence of double cystic arteries

Many variations of the coeliac trunk and hepatic or gallbladder arterial supply have been reported before in many cadaveric and radiologic studies. In this case we present combined anomalies observed in dissected cadaver of a 73-year-old female. The left gastric artery arises directly from the abdominal aorta and gives two branches: the right inferior phrenic artery in the proximal part and the accessory left hepatic artery in the distal part. The coeliac trunk is bifurcated into the common hepatic artery and the splenic artery. The right gastric artery emerges from the left hepatic artery. The right hepatic artery gives two cystic arteries and the accessory right hepatic artery is noticed arising from the posterior superior pancreaticoduodenal artery. The deep cystic artery and the right inferior phrenic artery give hepatic branches. Also, we noticed small accessory biliary duct going to the cystic duct. This complexity of the arterial supply with anomaly of the biliary ducts has many surgical implications which will be herein discussed.

Anatomical variants of coeliac trunk in Polish population using multidetector computed tomography angiography

BACKGROUND

Multidetector computed tomography angiography (MDCTA) has become a major part in evaluation of normal anatomy and its variants in patients undergoing operative or interventional procedures. The purpose of this study was to assess the frequency of anatomical variation of coeliac trunk in patients undergoing MDCTA of the abdominal aorta.

MATERIALS AND METHODS

A descriptive, retrospective study was carried out on MDCTAs performed from January 2014 till January 2020 in Polish patients. Coeliac trunk was studied and normal and anatomical variations were noted according to Adachi's classification. All patients with abnormalities affecting the vessels or a history of any vascular abnormality were excluded from the study.

RESULTS

Out of total 1000 patients, hepatogastrosplenic trunk was found in 93.0%. True and false types of trifurcation were observed. Hepatosplenic trunk was found in 2.8%, coeliacomesenteric trunk in 1.1%, hepatomesenteric trunk in 1.7% gastrosplenic trunk was found in 1.4%. We have not observed hepatosplenomesenteric trunk.

CONCLUSIONS

The type and knowledge of anatomy is of prime importance for an optimum preoperative planning in surgical or radiological procedure. MDCTA allows minimally invasive assessment of arterial anatomy with high quality three-dimensional reconstruction images.

Coeliac trunk and its anatomic variations: a cadaveric study

BACKGROUND

Coeliac trunk (CT) is the first major visceral branch of the abdominal aorta. The aim of this work was to present the CT division pattern and its anatomical variants in a sample of Polish population.

MATERIALS AND METHODS

Coeliac trunk dissection was performed in 50 adult cadavers in the Department of Anatomy, Jagiellonian University Medical College. Cadavers of Polish subjects were included. Cadavers with previous upper abdominal surgery, abdominal trauma, disease process that distorted arterial anatomy or signs of putrefaction were excluded. CT variations, accessory vessels, and vertebral level of origin were described. CT patterns were reported according to the Adachi classification. This study was reviewed and approved by the local Ethics Committee.

RESULTS

Coeliac trunk consisting of the left gastric, common hepatic and splenic artery (type 1 according to the Adachi classification) was found in 82% of cadavers. The true tripod was found in 20% and the false one in 80%. Additional vessels were also found: greater pancreatic from the splenic artery and left inferior phrenic from the left gastric artery, which accounted for 2% sections. Type 2 according to the Adachi classification (i.e. the hepatosplenic trunk) was found in 16% of the sections. Other types of CT were not observed. The level of origin was found to be at the inter-vertebral disc between T12 and L1 in all of the cases.

CONCLUSIONS

Based on the analysis of the sectional material of the Department of Anatomy, it was found that the typical visceral segmental division is approximate to that observed by Adachi in its classification, whereas the second type of CT was twice as frequent and no other, less frequent types were found.

Do we really need three-dimensional convex inguinal hernia meshes?

PURPOSE

The aim of our study was to assess the anatomical variability in the curvature of the muscles in inguinal region and to determine the necessity of using three-dimensional convex-shape hernia meshes in spite of typical flat ones.

METHODS

The group analyzed consisted of 180 patients with no abnormalities in inguinal region: 30 males and 30 females for every subgroup, with decreased, normal, and increased BMI. For every patient a 3D software model of muscles in the inguinal region was built, based on the segmentation of pelvic CT images and its outer surface determining the shape of the hernia mesh was created. Correlation was tested between the diameter of sphere describing the shape, the height of mesh top, and BMI. The optimal number and diameter of prefabricated hernia mesh set was obtained.

RESULTS

Only a moderate correlation (r = - 0.32) was found between the diameter of sphere and BMI in females and between the height of the mesh top and BMI in females (r = 0.43) and in the whole group of patients (r = 0.33). Accepting fitting error < 5 mm for 62 from 180 cases there was no need to use a convex-shape hernia mesh, for the other cases one of 3 prefabricated hernia meshes with diameters: 854 mm, 434 mm, 298 mm was sufficient.

CONCLUSIONS

For about one-third of patients a commonly used flat hernia mesh is adequate, for the rest of the cases one of 3 convex-shape meshes is sufficient.

Potential for a localized immune response by the ruminal epithelium in nonpregnant heifers following a short-term subacute ruminal acidosis challenge

The aim of this study was to investigate whether the ruminal epithelium activates a local inflammatory response following a short-term subacute ruminal acidosis (SARA) challenge. Seven ruminally cannulated, nonpregnant, nonlactating beef heifers, fed a baseline total mixed ration (TMR) with 50:50 forage-to-concentrate ratio, were used in a crossover design with 2 periods and 2 treatments: SARA and control (CON). Induction of SARA included feed restriction (25% of dry matter intake [DMI] for 24 h) followed by a grain overload (30% of baseline DMI) and provision of the full TMR; whereas, the CON group received the TMR ad libitum. Ruminal pH was recorded using indwelling probes, and ruminal lipopolysaccharide (LPS) concentration was measured daily following the challenge until d 6. Biopsies of ruminal papillae from the ventral sac were collected on d 2 and 6 after the grain overload. Transcript abundance of genes associated with acute inflammation was measured by quantitative real-time PCR, normalized to the geometric mean of 3 stable housekeeping genes. Target genes included toll-like receptor-2 (TLR2), TLR4, TLR9, tumor necrosis factor-α (TNFA), prostaglandin endoperoxide synthase-1 (PTGS1), PTGS2 transforming growth factor β-1 (TGFB1), and 4 intermediate enzymes of leukotriene synthesis (ALOX5, ALOX5AP, LTA4H, and LTC4S). Protein localization and expression of TLR4 were quantified by image analysis of fluorescence intensity. Statistical analysis was performed using as a crossover design with fixed effects of treatment, day, and the treatment × day interaction with the random effect of day within period. Ruminal pH was below 5.6 for 4.5 h/d and below 5.8 for 6.9 h/d in the SARA group compared with 22 and 72 min/d, respectively, for CON. Ruminal LPS concentration peaked on d 2 in SARA heifers at 51,481 endotoxin units (EU)/mL compared with 13,331 EU/mL in CON. Following grain overload, small but statistically significant decreases in the transcriptional abundance of TLR2, TLR4, TNF, PTGS2, ALOX5, and ALOX5AP were seen in SARA versus CON heifers. A functionally relevant decrease in TLR4 expression in SARA heifers compared with CON was confirmed by a decrease in fluorescence intensity of the corresponding protein following immunohistofluorescent staining of papillae. The study results indicate a suppression of the inflammatory response in the ruminal epithelium and suggest that the response is tightly regulated, allowing for tissue recovery and return to homeostasis following SARA.

Lipectomy Technique as a Second-stage Procedure for Primarily Matured, Deep Outflow Vein in Obese Individuals

Prevalence of obesity is growing in the general population as well as among end-stage renal disease (ESRD) patients requiring dialysis. Obesity often leads to a situation when a mature outflow vein is located deeper than 6 mm and is difficult to cannulate. These obese patients usually require additional procedures to able to successfully cannulate the fistula. The available surgical options include: outflow vein elevation, liposuction, and lipectomy. We present a case of a 57-year-old obese female with ESRD and matured, deeply running, inadequate for cannulation arteriovenous fistula. We present a technique of lipectomy with wide resection of adipose tissue from superior and lateral surfaces of outflow vein. Postoperatively, the skin without the underlying adipose tissue collapses allowing easy cannulation of the long segment of outflow vein with two needles. Lipectomy of mature but deeply located outflow vein is a second-stage elective procedure. Wide resection of adipose tissue helps create easy to access cannulation zone in obese individuals.

Effectiveness and Safety of Recombinant Human Erythropoietin (r-HuEPO) in the Treatment of Anemia of Chronic Renal Failure in Non Dialysis Patients

Seventy-five non-dialized patients with chronic renal failure (CRF) and severe renal anemia were enrolled in a study, receiving r-HuEPO subcutaneously thrice weekly for 6 months. In 64 patients (85%) 7 weeks of treatment with a weekly dose of 158 U/kg were required to achieve Hb concentrations within the target range of 10 to 12 g/dl. Of the 11 patients (15%) who failed to achieve the target Hb range, none were considered to be non-responders as they were excluded for unrelated reasons prior to week 16 (8 cases), or were iron deficient (2 cases), or had bleeding complications (1 patient). Maintaining the Hb concentration at a level of 10.5 g/dl required a mean r-HuEPO dose of 92 U/kg per week. Adverse events were generally mild or moderate. The most commonly reported were hypertension (8%), viral infection/including flu-like syndrome (7%), nausea (7%), and dizziness (5%). Statistically significant increases in mean creatinine concentrations observed after 12 and 24 weeks were most likely due to the progression of renal disease. These results confirm that 50 U/kg of r-HuEPO given 3 times per week subcutaneously provide a safe and effective therapy for anemic predialysis patients.

Interstitial cells of Cajal - systematic review

This paper reviews the distribution of interstitial cells of Cajal (ICC) in the human gastro-intestinal (GI) tract, based on ultrastructural and immunohistochemical evidence. The distribution and morphology of ICC at each level of the normal GI tracts is addressed from the perspective of their functional significance. Alterations of ICC reported in as well as in GI stromal tumours are reviewed, with emphasis on the place of ICC in the pathophysiology of disease.

Abrikossoff's tumor mimicking endometrial tumor--literature review and case report of the first described granular cell tumor in scar tissue after caesarean section

Abrikossoff's tumor (AT) is a rare, predominantly benign, asymptomatic, solitary, less than three cm-in-size tumor with usually favorable prognosis after surgical excision. Most of the tumors are found in the head and neck location in the third to fifth decade of life. Local wide excision, which is a treatment of choice, is curative in most of the cases.The case of 34-year-old female patient the authors report herein is the first described AT located in scar tissue after caesarean section. Physical and ultrasound examinations revealed a well-circumscribed, two-cm-in-size mass located in the fascia level. With a preoperative suspicion of endometrial tumor, the patient underwent surgery. Tumor was excised with wide tissue margin. Postoperative pathologic analysis revealed the presence of granular cell myoblastoma and was essential giving definitive diagnosis.

The porcine innate immune system: an update

Over the last few years, we have seen an increasing interest and demand for pigs in biomedical research. Domestic pigs (Sus scrofa domesticus) are closely related to humans in terms of their anatomy, genetics, and physiology, and often are the model of choice for the assessment of novel vaccines and therapeutics in a preclinical stage. However, the pig as a model has much more to offer, and can serve as a model for many biomedical applications including aging research, medical imaging, and pharmaceutical studies to name a few. In this review, we will provide an overview of the innate immune system in pigs, describe its anatomical and physiological key features, and discuss the key players involved. In particular, we compare the porcine innate immune system to that of humans, and emphasize on the importance of the pig as model for human disease.

Digit loss due to Demodex spp. infestation in a dog: clinical and pathological features

Here we describe a rare clinical manifestation of canine pododemodicosis. A dog was presented with pedal erythema, scaling, crusting, severe edema and digit loss. The following diseases were taken into account for the differential diagnosis: pododemodicosis, lethal acrodermatitis, zinc responsive dermatosis and pemphigus foliaceus. Results from skin biopsies revealed the presence of Demodex spp. of mites in the follicular infundibula and a severe inflammatory process (pododemodicosis). Upon the acaricidal treatment, the patient exhibited favorable signs of clinical improvement.

Somatostatin receptor subtypes 2 and 5 mediate inhibition of egg yolk-induced gall bladder emptying in mice

BACKGROUND

Somatostatin inhibits gall bladder contraction. Impaired gall bladder emptying is associated with gall bladder stone formation. The incidence of cholecystolithiasis is high in patients treated with a somatostatin agonist octreotide, which predominantly interacts with somatostatin receptor subtype 2 (SSTR2). Therefore, it is believed that SSTR2 regulates gall bladder contraction; however, evidence has not been provided. Here, we evaluate the effects of SSTR1-SSTR5-selective agonists on egg yolk-induced gall bladder contraction in mice.

METHODS

Homozygous deletion of SSTR2 and SSTR5 was generated by cross-mating of SSTR2(-/-) with SSTR5(-/-) mice. Mice of different genotypes were injected with SSTR1-5-selective agonists or octreotide 15 min before induction of gall bladder emptying by egg yolk. One hour later, gall bladders were removed and weighed.

KEY RESULTS

Egg yolk-reduced gall bladder weights in all mice, irrespective of their genotype. Octreotide was the most potent inhibitor of gall bladder emptying in wild-type mice. In contrast, agonists with high selectivity for SSTR2 or SSTR5 inhibited gall bladder emptying by approximately 50-60%, whereas SSTR1-, SSTR3- and SSTR4-selective agonists failed to influence gall bladder contraction. In SSTR2(-/-) mice, octreotide and an SSTR5-selective agonist inhibited gall bladder emptying by approximately 50%, whereas SSTR2-selective agonists were inactive. Octreotide inhibited gall bladder emptying in SSTR5(-/-) mice by approximately 50%, without any effect in SSTR2(-/-)/SSTR5(-/-) mice.

CONCLUSIONS & INFERENCES

Our study provides evidence for the role of SSTR2 and SSTR5 in regulating gall bladder emptying in mice.

Nature of phosphorus limitation in the ultraoligotrophic eastern Mediterranean

Phosphate addition to surface waters of the ultraoligotrophic, phosphorus-starved eastern Mediterranean in a Lagrangian experiment caused unexpected ecosystem responses. The system exhibited a decline in chlorophyll and an increase in bacterial production and copepod egg abundance. Although nitrogen and phosphorus colimitation hindered phytoplankton growth, phosphorous may have been transferred through the microbial food web to copepods via two, not mutually exclusive, pathways: (i) bypass of the phytoplankton compartment by phosphorus uptake in heterotrophic bacteria and (ii) tunnelling, whereby phosphate luxury consumption rapidly shifts the stoichiometric composition of copepod prey. Copepods may thus be coupled to lower trophic levels through interactions not usually considered.

Growth and development of Argulus coregoni (Crustacea: Branchiura) on salmonid and cyprinid hosts

The obligate fish ectoparasite Argulus coregoni is strictly specific to salmonids and is very rarely found on other fish species. The ability of the parasite to grow and complete its life cycle on a cyprinid host, Rutilus rutilus, was compared with that on a typical salmonid host, Oncorhynchus mykiss. Rearing experiments were run for 42 d with newly hatched metanauplii in flow-through tanks. Body length and sex of the parasites were recorded every 5 d. Growth rates on O. mykiss exceeded those on R. rutilus from the age of 2 wk, at which time the parasites reached a length of about 3.5 mm. Males grew faster than females at the beginning of the experiment up to a length of 2.5 to 3.0 mm; thereafter, a faster growth rate was observed in females. In another experiment, association of parasites with the hosts was monitored and residence time defined as the period between attachment and first detachment from the host. Longer residence time was observed on O. mykiss than on R. rutilus; female parasites stayed on both fish species longer than did males. Faster growth of parasites could be associated with longer uninterrupted periods of attachment to hosts, since frequent detachment means higher energy losses and less time available for feeding. Despite its slower growth on R. rutilus, A. coregoni matured and laid egg clutches, but took 5 d longer than on O. mykiss. The potential of A. coregoni to complete its life cycle on cyprinids could have important ecological consequences, creating an infection reservoir when the main salmonid hosts are rare or temporarily missing.

The energetic cost of induced fit catalysis: Crystal structures of trypsinogen mutants with enhanced activity and inhibitor affinity

The contribution of induced fit to enzyme specificity has been much debated, although with little experimental data. Here we probe the effect of induced fit on enzyme specificity using the trypsin(ogen) system. BPTI is known to induce trypsinogen to assume a trypsinlike conformation. Correlations are observed between BPTI affinity and the values of k(cat)/K(m) for the hydrolysis of two substrates by eight trypsin(ogen) variants. The slope of both correlations is -1.8. The crystal structures of the BPTI complexes of four variant trypsinogens were also solved. Three of these enzymes, K15A, DeltaI16V17/D194N, and DeltaI16V17/Q156K trypsinogen, are 10- to 100-fold more active than trypsinogen. The fourth variant, DeltaI16V17 trypsinogen, is the lone outlier in the correlations; its activity is lower than expected based on its affinity for BPTI. The S1 site and oxyanion hole, formed by segments 184A-194 and 216-223, are trypsinlike in all of the enzymes. These structural and kinetic data confirm that BPTI induces an active conformation in the trypsin(ogen) variants. Thus, changes in BPTI affinity monitor changes in the energetic cost of inducing a trypsinlike conformation. Although the S1 site and oxyanion hole are similar in all four variants, the N-terminal and autolysis loop (residues 142-152) segments have different interactions for each variant. These results indicate that zymogen activity is controlled by a simple conformational equilibrium between active and inactive conformations, and that the autolysis loop and N-terminal segments control this equilibrium. Together, these data illustrate that induced fit does not generally contribute to enzyme specificity.

Proton and metal ion-dependent assembly of a model diiron protein

DF1 is a small, idealized model for carboxylate-bridged diiron proteins. This protein was designed to form a dimeric four-helix bundle with a dimetal ion-binding site near the center of the structure, and its crystal structure has confirmed that it adopts the intended conformation. However, the protein showed limited solubility in aqueous buffer, and access to its active site was blocked by two hydrophobic side chains. The sequence of DF1 has now been modified to provide a very soluble protein (DF2) that binds metal ions in a rapid and reversible manner. Furthermore, the DF2 protein shows significant ferroxidase activity, suggesting that its dimetal center is accessible to oxygen. The affinity of DF2 for various first-row divalent cations deviates from the Irving-Willliams series, suggesting that its structure imparts significant geometric preferences on the metal ion-binding site. Furthermore, in the absence of metal ions, the protein folds into a dimer with concomitant binding of two protons. The uptake of two protons is expected if the structure of the apo-protein is similar to that of the crystal structure of dizinc DF1. Thus, this result suggests that the active site of DF2 is retained in the absence of metal ions.

New phenolic antioxidants of PYA and PYE class increase the resistance S. cerevisiae strain SP4, its SOD- and catalase-deficient mutants to lipophilic oxidants

Was demonstrate the protection ability against reactive oxygen species afforded to S. cerevisiae (wild-type strain SP4 and its mutants deficient in major antioxidant enzymes--catalase T and A, CuZnSOD) by PYA and PYE, new groups of phenolic antioxidants (quaternary ammonium salts of dihydrocinnamic acid amino esters with different alkyl chains; synthesized in this laboratory). The survival of strains exposed to the lipophilic oxidation inducers tert-butyl hydroperoxide (TBHP) and 1,1'-azobis(4-cyclohexane carbonitrile) (ACCN) with or without antioxidant pretreatment was determined by plating. S. cerevisiae mutant deficient in SOD was found to be hypersensitive to TBHP and ACCN while the sensitivity of the strain deficient in catalase T and A was about the same as in the wild-type strain. A 1-h preincubation of cells of both the wild-type and the mutant strains with the phenolic antioxidants prior to exposure to TBHP or ACCN substantially increased the cell survival. The magnitude of protection depended on the strain and the length of the alkyl chain of the antioxidant; the best average protection against TBHP was provided by PYE and PYA compounds with 12- and 16-membered alkyl chains whereas PYE-8 and PYA-12 derivatives afforded the best average protection against ACCN.

Nipecotic and iso-nipecotic amides as potent and selective somatostatin subtype-2 receptor agonists

N-Substituted nipecotic and iso-nipecotic amides of beta-methylTrpLys tert-butyl ester were found to be novel, selective and potent agonists of the somatostatin subtype-2 receptor in vitro. For example iso-nipecotic amide 8a showed high hsst2 binding affinity (Ki = 0.5 nM) and good selectivity (h5/h2 = 832).