bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on the Interaction of Human Phospholipid Scramblase 1 with C‐Terminal Domain of Topoisomerase IIα
Authors: Sivagnanam Ulaganathan , Gummadi Sathyanarayana Naidu
Published: November 2023

Human phospholipid scramblase 1 (hPLSCR1) is a multifunctional protein that plays key roles in several cellular processes including apoptosis, tumorigenesis, anti‐viral defense, cell signalling and several protein‐protein interactions. It has been shown that hPLSCR1 interacts with the C‐terminal domain of topoisomerase IIα (topo IIα) and enhances its decatenation activity in vitro. The interacting region in topo IIα was identified but till date, no reports exist on the binding region in hPLSCR1. This study aims to identify the region of hPLSCR1 that interacts with topo IIα. To identify the topo IIα interacting sites in hPLSCR1, N‐terminal deletion constructs of hPLSCR1 viz Δ25‐hPLSCR1, Δ50‐hPLSCR1, Δ75‐hPLSCR1, Δ100‐hPLSCR1 and Δ160‐hPLSCR1 were generated by PCR, cloned, overexpressed and purified to homogeneity using Ni2+‐NTA purification. The C‐terminal domain (CTD) of topo IIα was cloned in pGEX6P‐1 and was expressed as a GST fusion protein. GST pull down assays will be performed with the deletion constructs of hPLSCR1 and the GST‐CTD‐topo IIα. The binding region in hPLSCR1 will be confirmed by peptide competition assays. Our initial results show that the decatenation activity of topo IIα was enhanced when topo II was pretreated with hPLSCR1. Δ100‐hPLSCR1 did not show any enhancement of the decatenation activity compared to full length hPLSCR1. Hence, the binding region could be in the 1–100 region of hPLSCR1. Further deletions were done in the 1–100 region of hPLSCR1 as described earlier. GST‐pull down assays and decatenation assays will be performed for the deletion constructs to narrow down the region of hPLSCR1 that binds to topo IIα. We conclude that hPLSCR1 interacts with and enhances the activity of topo IIα and the 1–100 region of hPLSCR1 is critical for enhancement of decatenation activity. Further work is under progress to identify the exact topo IIα binding region of hPLSCR1 and the physiological relevance of this interaction in the cell.

Support or Funding Information

This work was funded by Council of Scientific and Industrial Research (CSIR), Government of India. Authors thank Ministry of Human Resources and Development Govt. of India and Indian Institute of Technology Madras for fellowship.
ICAM‐1 Augments Myoblast Fusion through Homophilic Interactions
Authors: Springer Evan , Martin Ryan , Leffler Maxwell , Woelmer Bryce , Leaman Douglas , Pizza Francis X.
Published: November 2023

We previously demonstrated that intracellular adhesion molecule‐1 (ICAM‐1) expression by satellite cells/myoblasts contributes to muscle regeneration in vivo and augments myogenesis in vitro. Recently, we demonstrated that forced expression of ICAM‐1 by cultured myoblasts enhances myoblast‐myoblast adhesion through homophilic trans‐interactions. The primary purpose of this study was to determine if homophilic trans‐interactions for ICAM‐1 augments myoblast fusion to myoblasts and myotubes. A secondary purpose was to determine if ICAM‐1‐ICAM‐1 interactions augment the myogenic conversion of fibroblasts. Hypotheses were tested in cell mixing experiments using control myoblasts and fibroblasts, which do not express ICAM‐1, ICAM‐1+ fibroblasts, and ICAM‐1+ myoblasts that express green fluorescent protein in the nucleus. We found that homophilic trans‐interactions for ICAM‐1 augmented myotube formation and myonuclear accretion. In addition, ICAM‐1‐ICAM‐1 interactions between myoblasts and fibroblasts did not enhance the myogenic conversion of the fibroblasts. We conclude that ICAM‐1 augments myoblast fusion to myoblasts and myotubes through its ability to self‐associate.
Color Vision and Signal Color Evolution in Anolis lizards
Authors: Maximov Katherine Joy , Wadman Catherine
Published: November 2023

Animals rely on different signaling patterns to communicate both within and between different species. Anolis is a diverse genus of small arboreal lizards that utilize a colorful expandable throat‐fan (or dewlap) for visual communication, in order to attract females and repel males. The environment the lizard lives in has influenced the coloring of these dewlaps in different species. Species that occupy shaded habitats tend to have yellow dewlaps while those that inhabit brighter, less shaded, habitats, tend to have red or orange dewlaps. Natural backgrounds are formed by green vegetation. Modelling these dewlap colors in a perceptual color space predicts that red is more visible against a green background than yellow, yet studies have shown that the majority of anoles have yellow dewlaps. However, quantal fluctuations under low lighting may result in a higher degree of receptor noise for some colors which can affect the discrimination of one color from another by changing the distance between them in perceptual color space. Modelling that takes receptor noise into account predicts that yellow colors, which reflect more photons, will be more visible than red in low light conditions, while red should be more visible in bright light where receptor noise is less.

In this experiment, we used a color perception assay to test whether a red or yellow stimulus was more visible to the lizard under different light intensities against a green background, mimicking a dewlap appearing in a forested or open habitat. We flashed red, yellow, and green (control) stimuli against a green background. If the lizard detected a change, indicated by a swift head or eye movement towards the stimulus, a positive response was noted. We found that there was a significantly greater response to red stimuli in high light compared to low light. The visibility of yellow, however, did not change significantly with light intensity. In high light there was a greater response to red than to yellow, while in low light there was a greater response to yellow than to red. Our experiment confirmed the results predicted by the perceptual color space model when accounting for receptor noise. Since light intensity has a greater effect on the discriminability of red against green than yellow against green, this may account for the prevalence of yellow dewlaps in shaded habitats.
Influence of Spinal Neurotransmission on Renal Sympathetic Nerve Activity in Renovascular Hypertension
Authors: Campos Ruy R , Milanez Maycon I. O. , Nishi Erika E , Bergamaschi Cássia T
Published: November 2023

Studies performed in our laboratory showed a higher glutamate and angiotensin II type 1 (AT1) receptors activation in the rostral ventrolateral medulla (RVLM) that may lead to sympathoexcitation in renovascular hypertensive rats. However, the role of the spinal cord neurons on the renal sympathoexcitation remains unclear in this model. Thus, we aimed to assess the influence of spinal glutamatergic (ionotropic receptors) and AT1 receptors on the renal sympathetic nerve activity (RSNA) and blood pressure (BP) in renovascular hypertension. Male Wistar (250–300g) rats were divided into two independent groups: CTL‐control rats (n=11) and 2K1C‐hypertensive rats (n=9). All experiments were approved by the Institutional Ethical Committee. Renovascular hypertension was induced by clipping the renal artery with a silver clip. After six weeks, a polyethylene catheter (PE‐10) was inserted into the subarachnoid space and advanced to the T10–11 vertebrae level in urethane‐anaesthetized rats (1,2 g/Kg, iv). The effects of intrathecal (i.t.) injection of kynurenic acid (KYN) (2 μl, 160 nmol) or losartan (Los) (2 μl, 2nmol) on BP and RSNA were analyzed for 2 consecutive hours. KYN i.t. injection induced a larger and significant fall on RSNA in the 2K1C compared with control group (CTL × 2K1C: −8 ± 3 × −52 ± 9* spikes/s after 120′). Los i.t. injection also evoked a larger and significant fall in RSNA in the 2K1C compared with control group from 80' after Los i.t. administration (CTL × 2K1C – 80 min: −10 ± 2 × −32 ± 6*; 100 min: −15 ± 4 × −37 ± 9*; 120 min: −12 ± 5 × −37 ± 8* spikes/s). KYN decreased BP similarly in CTL and 2K1C groups, however, Los significantly decreased BP in the 2K1C group only. Therefore, our data show that ionotropic spinal cord excitatory aminoacid and AT1 receptors play an important role in the control of RSNA in the 2K1C model that may contribute to the maintenance of hypertension. The origin of those projections remains unclear. *p<0,05.

Support or Funding Information

CNPq, FAPESP (13/22522‐9), CAPES.
The Human Milk Oligosaccharide 3–Fucosyllactose Facilitates Preservation of Nitric Oxide‐Induced Vasodilation in Aortic Vessels In vitro
Authors: Varadharaj Saradhadevi , Helal Mustafa , Duska‐McEwen Geralyn O , Boslett Jim , Pereira Suzette L , Buck Rachael H , Ahmed Naseeruddin , Zweier Jay L
Published: November 2023

Background

The human milk oligosaccharides (HMOs) 2′‐Fucosyllactose (2′‐FL) and 3‐Fucosyllactose (3‐FL) structurally mimic human histo‐blood group antigens. It is estimated that ~1% of HMOs consumed are absorbed systemically. Although HMOs can reduce platelet‐neutrophil complex formation in vitro, direct effects on endothelial vascular reactivity and tone following an inflammatory stimulus are unknown. In vascular disease associated with intestinal ischemia, coronary ischemia, hypertension, diabetes and hyperlipidemia, vasodilation is impaired due to loss of endothelial nitric oxide synthase (eNOS) function with a pivotal switch from production of the vasodilator nitric oxide (NO) to vasoconstrictor superoxide (O2•−). Necrotizing enterocolitis (NEC) is a risk factor in premature infants with congenital heart disease and pulmonary hypertension due to altered vascular reactivity. We hypothesize that HMO facilitates NO‐mediated vascular smooth muscle cell relaxation leading to increased vasodilation. Therefore, we investigated the effect of HMO‐3‐FL on NO‐dependent aortic vessel relaxation.

Methods

Studies were performed using rat thoracic aortic rings treated with or without 3‐FL and the vessel rings were grouped as Control, Lipopolysaccharide (LPS), LPS + 3‐FL. The rings were pre‐incubated with 3‐FL (250 μg/500 μl) followed by incubation with LPS for 4 hours in 5 μg/500 μl LPS/media. The rings were then assessed for endothelial‐dependent and independent relaxation by pre‐constricting vessels with phenylephrine (PHE) 1 μM and then progressive addition of acetylcholine (Ach) 0.001 to 100 uM or nitroprusside (SNP), 0.01 – 1000 nM. Vasorelaxation was calculated as a percentage of the PE‐induced maximal response.

Results and Discussion

Cumulative dosing of Ach or SNP to PHE‐pre‐constricted rings caused typical dose‐dependent relaxation in control aortic rings. However, after LPS treatment, this response was impaired with ~80% decrease. In rings that were pre‐incubated with 3‐FL, significant preservation of relaxation was seen with over 50% higher maximal relaxation compared to vehicle control LPS treatment. When pre‐incubated with 3‐FL (0.5mg/ml) the LPS stimulated aortic rings showed an increase in vasorelaxation (p<0.05) over the full dose range of NO donor (SNP). Thus, 3‐FL enhanced endothelial‐independent relaxation, which is based on the function of the smooth muscle in the vessel wall. These results suggest an approach to prevent or limit NEC by reversing vasoconstriction. Preservation of vasomotor activity and vasodilation by HMOs may provide a novel nutritional approach for the prevention of NEC‐associated vascular dysfunction.
Nutrition versus Functional Respiratory Capacity: A Cardinal Interplay
Authors: Chakrabarty Kaveri , Gautam Dinesh Kumar , Guha Satyakam , Arora Anubhuti , Das Anup , Aggarwal Deepak , Gulati Divya , Sharma Harshita , Yadav Nitin , Chakraborty Ranabir , Thapliyal Somesh , Rathi Utkarsha , Chaudhary Vikas
Published: November 2023

Right from the very beginning of life on earth, organisms have always been in search for sources of energy. From the most primitive of organisms to where biodiversity stands today, the demand of energy has always been met by the supply of food. Nutrition plays a crucial role in normal functioning of all the organs of our body. Any form of imbalance in the dietary intake becomes evident in the concerned physiology. This study was undertaken to explore the variations of Functional Respiratory Capacities (FRCs) associated with diet and the underpinned lifestyle habits in a sample of 70 (36 male/34 female) college going students in Delhi within the age group of 19–21.

Balanced diet is a pre‐requisite for a healthy lifestyle. But one of the major problems faced by developing countries is malnourishment, wherein the nutrient intake is either insufficient or over‐sufficient. As dyspnea and poor lung volumes are theoretically expected in people with the global phenomenon of obesity, this study aimed at correlating the data of three major functional respiratory parameters, Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second of expiration (FEV) and FEV % {(FEV /FVC) × 100} obtained using a MiniSpir spirometer and the answers in the questionnaire concerning dietary and lifestyle habits filled by the volunteers themselves. An additional insight into the analysis was made by calculating the Body Mass Index (BMI) of the volunteers using a Tanita InnerScanV Body Composition Analyser.

The pulmonary function results obtained was typically a spectrum of restrictions and obstructions flanked by normal spirometry. Volunteers who indulged themselves in cigarettes and alcohol showed mild to severe obstructions, and those feeding on excessive calories showed mild to severe restrictions. High calorie intake (prolonged obesity) and cigarette smoking could increase the severity of the results (which were mild given the age group of volunteers) in due course of time, possibly deteriorating their pulmonary health further down the line.

Support or Funding Information

Research Council, University of Delhi
Buccal rhythm generation in metamorphic bullfrogs is dependent on glycine
Authors: Reed Mitchell , Iceman Kimberly , Varier Thorne , Harris Michael , Taylor Barbara
Published: November 2023

Fish and early developmental amphibians use gill structures to exchange gases in water. In jawless fish, the neural circuit responsible for generating gill ventilation (buccal) rhythm is adjacent to the trigeminal nerve (CN V). In amphibians, a homologous rhythm generating site has been identified just caudal to the vagus nerve (CN X). The amphibian buccal oscillator is reported to be driven by Cl− mediated mechanisms, and subsequent inhibition of either GABA or glycinergic receptors abolishes this rhythm. This study investigates the effects of Cl− mediated antagonism of buccal rhythm generation and the distribution of buccal rhythm generating circuits.

We isolated brainstems from bullfrog tadpoles, placed them in a recording chamber, and allowed them to recover for 1 hour perfused with artificial cerebral spinal fluid (aCSF) equilibrated with 98.5% O2 and 1.5% CO2 (pH 7.8). During this time, neural activity from the facial (CN VII) and hypoglossal (CN XII) cranial nerves was recorded. Following recovery, brainstems were either transected at the level of the glossopharyngeal nerve (CN IX), removing the caudal medulla (rostral to the amphibian “buccal oscillator”) or left intact. Activity from the trigeminal (CN V), facial (CN VII), or hypoglossal (CN XII) nerves were recorded. A cocktail containing bicuculline methochloride (5 μM) and strychnine (5 μM) or bicuculline or strychnine alone was subsequently bath applied for 30 minutes.

Small amplitude rhythms were observed following transection, similar to buccal rhythms of intact isolated brainstems. These were accompanied by large amplitude rhythms, which we consider putative lung rhythms. Upon application of bicuculline, putative buccal rhythms in transected and intact brainstems remained and lung activity increased. Application of strychnine alone or in the presence of bicuculline abolished the small amplitude rhythm, and still enhanced lung activity. These results suggest that buccal‐like rhythms are glycine dependent, and may be produced by a diffuse medullary network.

Support or Funding Information

Research reported in this publication was supported by the National Institute Of General Medical Sciences of the National Institutes of Health under Award Numbers UL1GM118991, TL4GM118992, or RL5GM118990. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Angiotensin‐(1–7) Promotes Resolution of the Inflammatory Process of Asthma
Authors: Campagnole‐Santos Maria Jose , Magalhaes Giselle Santos , Rodrigues‐Machado M Gloria , Gregorio Juliana Fabiana , Reis Alessandra , Pinho Vanessa , Barcelos Luciola , Santos Robson A S
Published: November 2023

Recent studies advanced our understanding on the renin‐angiotensin system actions in the pathogenesis of several diseases. We now recognize angiotensin‐(1–7) [Ang‐(1–7)] as having pivotal role in antagonizing cell proliferation, tissue fibrosis and inflammation. We previously showed that Ang‐(1–7) attenuates chronic allergic lung inflammation and airway hyperresponssiveness. In this study, we investigated the effect of Ang‐(1–7) in the resolution of the allergic lung inflammatory response. Balb/c mice were randomly assigned to three groups: Control group; ovalbumin (OVA)‐sensitized and ‐challenged group; and ovalbumin‐sensitized and ‐challenged group treated with Ang‐(1–7). Sensitization was made by two injections of OVA (50 μg per mouse, i.p) in 2% aluminum hydroxide gel adjuvant at 7 days interval. On the 12nd day, sensitized mice received OVA challenge until 19th day (10 μg of OVA or PBS, intranasal). Ang‐(1–7) treatment (2μg/ mouse, v.o.) 24h after the last OVA challenge. Mice were killed by anesthetic overdose, 24h after Ang‐(1–7) treatment and bronchoalveolar lavage fluid (BALF) was made and next, lungs were collected. Morphometric analysis and determination of ERK1/2, IκB‐α and GATA3 by Western blotting were performed in the lung. Analysis of the number of inflammatory cells and immunofluorescence for Caspase 3 and NF‐κB were performed in the BALF. Efferocytosis assay was performed in different group of FVBN mice. Briefly, human neutrophil apoptotic cells were injected i.p. in zymosan‐induced peritonitis mice control or treated with Ang‐(1–7) (3μg). The peritoneal lavage was collected. Ang‐(1–7) promotes resolution of airway inflammation by induction apoptosis and inhibition of NF‐κB in eosinophils. Ang‐(1–7) also increased efferocytosis. In addition, treatment with Ang‐(1–7) reduced the GATA‐3, ERK1/2 and IκB‐α expression in lung of asthmatic animals and decrease pulmonary remodeling. Our results show that Ang‐(1–7) activates events that are crucial for the resolution of the inflammatory process and the return to homeostasis indicating Ang‐(1–7) as a novel endogenous pro‐resolving mediator. Support: FAPEMIG, CNPq, CAPES, INCT‐Nanobiofar

Support or Funding Information

Support: FAPEMIG, CNPq, CAPES, INCT‐Nanobiofar
Assessing cysteine residue thiol status in t‐Darpp, a protein involved in chemoresistance.
Authors: Aldana‐Mendoza Jesus Antonio , Farias Phillip , Momand Jamil Antonio
Published: November 2023

The gene PPP1R1B expresses t‐Darpp, a protein that activates protein kinase A and the AKT pathway in breast cancer cells. t‐Darpp, when overexpressed in breast cancer cells, also confers resistance to trastuzumab, a therapeutic that binds to the Her2 receptor. Although t‐Darpp expression is relatively high in gastric, breast and colon cancers, its structure is unknown. Human t‐Darpp has two cysteine residues that can be exploited to explore t‐Darpp structure, Cys36 and Cys119. Methoxypolyethylene glycol‐maleimide (Mal‐PEG) was used to determine whether recombinant t‐Darpp cysteine thiols are on the surface of the protein and to find out if they are reversibly oxidized. This study shows that the two cysteine thiols are either buried or oxidized. Further work will be conducted to distinguish between these two possibilities.

Support or Funding Information

the NIH RISE program # GM 08101
Activation and binding mechanisms of the tandem collagen‐binding domain of ColG collagenase
Authors: Bauer Ryan , Janowska Katarzyna , Tanaka Keisuke , Matsushita Osamu , Sakon Joshua
Published: November 2023

Clinically viable Clostridium histolyticum collagenases, ColG and ColH, contain variable numbers of collagen‐binding domains (CBD) (s3a‐s3b in ColG; s3 in ColH). These segments can be utilized to deliver therapeutics directly to their site of action. Since clinical outcomes depend on which binder is used, understanding the collagen‐binding and activation mechanisms are essential. To help elucidate these mechanisms, the crystal structure of the Ca2+‐bound ColG tandem CBD, has been solved at 1.9 Å resolution. The structure revealed a pseudo‐two fold symmetry arrangement of s3a and s3b that suggests that the domain can bind trans to two collagen molecules. Collagen fiber formation studies further supported this mechanism. Furthermore, it is thought that the difference in Ca2+ concentrations between the clostridial cell and host extracellular matrix (ECM) can be exploited to facilitate secretion into the ECM and subsequent activation. Structure envelopes derived from small angle X‐ray scattering data of tandem CBD in the presence of different Ca2+ concentrations showed structural compacting upon increasing Ca2+ concentrations. Insights gained form this study will help guide therapeutic delivery strategies.
The renal benzamil‐insensitive K+ excretion is independent of the BK channel
Authors: Jensen Iben Skov , Ruth Peter , Leipziger Jens Georg , Sørensen Mads Vaarby
Published: November 2023

Introduction

Two different secretory K+ channels are involved in the final homeostatic K+ excretion that takes place in the aldosterone‐sensitive distal nephron. One is the ROMK channel that co‐localizes with ENaC in the apical membrane of principal cells (PC) in the connecting tubule and collecting duct. PCs have a high expression of basolateral Na+/K+‐ATPase allowing for pump‐leak secretion of K+. K+ secretion via ROMK depends on Na+ reabsorption by ENaC to generate the necessary driving force.

The BK (KCa1.1) channel is the other secretory pathway and is primarily found in the apical membrane of intercalated cells. The cellular mechanism of BK‐mediated K+ secretion is not fully understood. It is associated with flow‐induced K+ secretion (FIKS), since the kaliuretic response to increased flow is attenuated in KCNMA−/− (BK‐α knockout) mice as well as in IbTX treated tubules. Benzamil inhibits renal K+ excretion, however, leaving a blocker‐insensitive component intact. After chronic high K+ diet the benzamil‐insensitive renal K+ excretion is upregulated. In this project we asked, if the benzamil‐insensitive K+ excretion is mediated by the BK channel.

Methods

The benzamil‐sensitive and ‐insensitive kaliuresis was investigated in vivo in KCNMA+/+ and KCNMA−/− mice. This was performed on either control or high K+ (5 %) diet. Mice were pretreated with vehicle or benzamil and then received a volume‐load via gavage containing either control (sucrose 2%) or high K+ (2 %). Gavage increased diuresis and thus flow in the distal tubules. This is seen both with control gavage, where excess K+ excretion is unnecessary, and with K+ gavage that should naturally increase the need for K+ excretion.

Results

We confirmed that benzamil attenuated, however, not completely abolished, urinary K+ excretion in all experiments. Hence, the K+ excretion could be divided into a benzamil‐sensitive and ‐insensitive fraction. The benzamil‐insensitive K+ excretion was upregulated by K+ loading, both acutely by K+ gavage but especially by chronic K+‐loading via high K+ diet. Importantly, we found no difference in the benzamil‐insensitive K+ excretion between KCNMA+/+ and KCNMA−/− mice in any of the investigated conditions.

Conclusion

Our data suggests (1) that K+ secretion via both ROMK and BK is highly dependent on ENaC activity and (2) that ROMK‐mediated K+ secretion compensates for the lack of BK‐mediated K+ secretion in KCNMA−/− mice. Furthermore (3), the benzamil‐insensitive K+ secretion appears independent of the BK channel and (4) is markedly regulated by both acute and chronic K+‐loading.
Multi‐Domain Dynamic Studies of Calcium Bound Polycystic Kidney Disease‐Like and Collagen Binding Domains
Authors: Ruth Christopher Eric , Sakon Joshua
Published: November 2023

Clostridium histolyticum secretes at least two collagenases, ColH and ColG, that allow for degradation of extracellular matrices of animal tissue. C. histolyticum collagenases virulence factors are proposed to undergo domain rearrangement upon secretion from the bacteria to the host. In order to accomplish this, collagenases seek the least ordered regions in collagen to efficiently disassemble the fibril. Two types of domains, Polycystic Kidney Disease‐Like (PKD) and Collagen Binding Domain (CBD), direct the collagenases ability to disassemble the fibril. Calcium dependent structural change, increases in thermal stability, increases in efficiency for collagen binding, for individual domains, PKD and CBD, have been reported. Different surface properties and indications of varied dynamics suggest unique roles for the PKD‐like domains in ColG and in ColH. These domains are useful in anchoring fused growth factors to lesions. The multi‐domain dynamics have been found to be dependent on calcium concentrations. Most recent results show that use of multi‐domain targeting segments result in more efficacious preclinical outcomes in various animal models. Single domain targeting segments have been extensively reported, however multi‐domain targeting segments have not been biophysically characterized. In this presentation, Small Angle X‐Ray Scattering (SAXS) methods were used to monitor calcium dependent structural change of multi‐domain segments. All SAXS data were collected at 10°C through the Advanced Light Source at Berkley National Lab (SIBYLS beamline, 12.3.1). The average of 33 beam exposures were collected and processed through primusqt (ATSAS 2.6.1 software package). The bacteria evolved to take advantage of calcium concentration differential between inside the bacteria and the extracellular matrix to efficiently secrete virulence factors.

Support or Funding Information

Supported by a grant from NIGMS (P20 GM103429) at NIH.
Surgical site infections in patients undergoing breast oncological surgery during the lockdown: An unexpected lesson from the COVID-19 pandemic
Authors: Cappelli Sonia , Corallino Diletta , Clementi Marco , Guadagni Stefano , Pelle Fabio , Puccica Ilaria , Barba Maddalena , Vici Patrizia , Sperduti Isabella , Costantini Maurizio , Botti Claudio
Published: November 2023

Background:

The present study aims to evaluate how the measures to contain the SARS-CoV-2 spreading affected the surgical site infections (SSIs) rate in patients who underwent nondeferrable breast cancer surgery (BCS).

Methods:

This study is a retrospective analysis of prospectively collected data from a consecutive series of patients underwent nondeferrable BCS in a regional Italian Covid-free hub during two different period: March to April 2020 (pandemic cohort [PC]) and March till April 2019 (control cohort [CC]). SSIs were defined according to the criteria established by the Center for disease control and prevention (CDC) and additional treatment, serous discharge, erythema, purulent exudate, separation of deep tissues, isolation of bacteria, and stay (ASEPSIS) scoring systems.

Results:

One hundred ninety-nine patients were included in the present study: 100 and 99 patients who underwent nondeferrable BCS from March to April 2020 (PC) and from March to April 2019 (CC), respectively. The overall SSIs rate in this series was 9.1% according to CDC criteria and 6.5% according to ASEPSIS criteria. The SSIs incidence decreased during the pandemic period. Moreover, the SSIs rate according to ASEPSIS criteria was statistically lower in the PC than in the CC. We observed significant evidence of higher SSIs, both in terms of CDC and ASEPSIS score, in patients having undergone breast reconstruction compared with patients not undergoing immediate reconstruction.

Conclusions:

The restrictive measures issued during the lockdown period seemed to lower the SSIs rates in patients undergoing nondeferrable BCS.
A case report of ectopic pancreas in the ileum incidentally diagnosed during laparotomy for acute colonic diverticulitis
Authors: Bigonzi Eleonora , Miconi Guglielmo , Colozzi Sara , Coletta Pietro , Palmieri Miriam , Ortenzi Monica , Guerrieri Mario
Published: November 2023

Ectopic or heterotopic pancreas (EP) is defined as pancreatic tissue lacking anatomic or vascular connections with the orthotopic pancreas. It is a rare entity that occasionally causes symptoms, in fact most cases are asymptomatic and they are diagnosed incidentally at laparotomy or during autopsy. This case report describes a 75-year-old woman presenting with acute colonic diverticulitis, scheduled for elective surgery. The preoperative CT virtual colonoscopy revealed a persistently enhanced mass in the proximal ileum, which was suspected for GIST or NET. Histopathological examination revealed pancreatic tissue without evidence of malignancy. Although the rarity of this clinical condition, it is necessary to be aware that jejunal EP can lead to complications, such as bleeding or jejunojejunal intussusception. Resection is the management of choice for incidentally found lesions assuming that the diagnosis of EP and exclusion of neoplasm may not be possible without a histological specimen.
Giant exophytic dermatofibrosarcoma protuberans of the breast
Authors: D’Onghia Giuliano , Sanguinetti Alessandro , Macciò Tiziana , Cirocchi Roberto , Avenia Stefano , Avenia Nicola , Izzo Paolo , Izzo Luciano , Gabriele Raimondo , Miccini Michelangelo , D’Ermo Giuseppe , Polistena Andrea
Published: November 2023

Dermatofibrosarcoma protuberans (DFSP) is a rare neoplasm characterized by a high rate of local recurrence and a low risk of metastases. Occurrence in the breast is extremely rare and requires an adequate preoperative diagnosis for a correct management. We report a case of a giant exophytic DFSP of the right breast in a young-aged woman. Radical mastectomy was carried out without clinical evidence of local recurrence after 2 years follow-up. Specific pathological features and recommendations for the clinical management are discussed.
Laparoscopic transanal total mesorectal excision (taTME) for rectal cancer
Authors: Conti Pietro , La Greca Giorgio , Muratore Andrea , Trombatore Giovanni
Published: November 2023

Background:

Total mesorectal excision (TME) and multimodal approach have incredibly changed the long-term outcomes of the patients with mid-low rectal cancer. Open or laparoscopic transabdominal TME represents the gold-standard approach to rectal cancer. However, up-to-down TME is technically demanding, especially in male patients with narrow pelvis, in obese patients. The transanal total mesorectal excision (taTME) seems to exceed the limits of the laparoscopic TME.

Methods:

After a training made of courses, cadaver-labs, and proctored cases, we approached transanally patients with mild-low rectal cancer. Between 2015 and 2020, 33 patients with rectal cancer have undergone laparoscopic taTME procedure with a single-team approach. Aim of the present paper is to report our initial experience in term of short terms outcomes and histological results.

Results:

Thirty-three patients with rectal cancer were included in this study: 19 males (57.6%) and 14 females (42.4%). The median distance of the rectal cancer from anal verge was 6.5 cm. Overall, 23 patients (69.7%) underwent long-course neoadjuvant therapy. The overall morbidity rate was 36% (12 patients). Anastomotic leak occurred in two patients (6.2%) that required reoperation. Postoperative mortality was 3%. Specimen was graded as complete in 100% of patients. Circumferential resection margin (CRM) was in median 6.52 mm (range 4–18 mm).

Conclusion:

The taTME is a safe alternative to standard laparoscopic TME in selected patients with low rectal cancer. This technique which would seem to be feasible if performed by an experienced colorectal surgeon even if practiced in a suburban hospital.
NADPH oxidase-mediated sulfenylation of cysteine derivatives is key regulatory events for plant immune responses
Authors: Hino Yuta , Inada Taichi , Yoshioka Miki , Yoshioka Hirofumi
Published: November 2023

Reactive oxygen species (ROS) are rapidly generated during plant immune responses by RBOH, which is a plasma membrane-localizing NADPH oxidase. Although regulatory mechanisms of RBOH activity have been well documented, the ROS-mediated downstream signaling is unclear. We here demonstrated that ROS sensor proteins play a central role in the ROS signaling via oxidative post-translational modification of cysteine residues, sulfenylation. To detect protein sulfenylation, we used dimedone, which specifically and irreversibly binds to sulfenylated proteins. The sulfenylated proteins were labeled by dimedone inNicotiana benthamianaleaves, and the conjugates were detected by immunoblotting. In addition, a reductant dissociated H2O2-induced conjugates, suggesting that cysteine persulfide and/or polysulfides are involved in sulfenylation. Sulfenylation of cysteine and its derivatives in ROS sensor proteins were continuously increased during both PTI and ETI in an RBOH-dependent manner. Pharmacological inhibition of ROS sensor proteins by dimedone perturbated cell death, ROS accumulation induced by INF1 and MEK2DD, and defense against fungal pathogens. On the other hand, Rpi-blb2-mediated ETI responses were rather enhanced by dimedone. These results suggest that the sulfenylation of cysteine and its derivatives in various ROS sensor proteins are important events in downstream of RBOH-dependent ROS burst to regulate plant immune responses.

Highlight

NADPH oxidase-mediated ROS production induces sulfenylation of cysteine residues or their derivatives of ROS sensor proteins, which regulates HR cell death, ROS accumulation, and defense against diverse plant pathogens.
Developmental trajectories and differences in functional brain network properties of preterm and at-term neonates
Authors: López-Guerrero N , Alcauter S
Published: November 2023

Premature infants, born before 37 weeks of gestation can have alterations in neurodevelopment and cognition, even when no anatomical lesions are evident. Resting-state functional neuroimaging of naturally sleeping babies has shown altered connectivity patterns, but there is limited evidence on the developmental trajectories of functional organization in preterm neonates. By using a large dataset (n=597) from the developing Human Connectome Project, we explored the differences in graph theory properties between at-term and preterm neonates at term-equivalent age, considering the age subgroups proposed by the World Health Organization for premature birth. Leveraging the longitudinal follow-up for some preterm participants, we characterized the developmental trajectories for preterm and at-term neonates. We found significant differences between groups in connectivity strength, clustering coefficient, characteristic path length and global efficiency. Specifically, at term-equivalent ages, higher connectivity, clustering coefficient and efficiency are identified for neonates born at later postmenstrual ages. Similarly, the characteristic path length showed the inverse pattern. These results were consistent for a variety of connectivity thresholds at both the global (whole brain) and local level (brain regions). The brain regions with the greatest differences between groups include primary sensory and motor regions and the precuneus which may relate to the risk factors for sensorimotor and behavioral deficits associated with premature birth. Our results also show non-linear developmental trajectories for premature neonates, but decreased integration and segregation even at term-equivalent age. Overall, our results confirm altered functional connectivity, integration and segregation properties of the premature brain despite showing rapid maturation after birth.
Well-Paired-Seq2: High-Throughput and High-Sensitivity Strategy for Characterizing Low RNA-Content Cell/Nucleus Transcriptomes
Authors: Yin Kun , Zhao Meijuan , Xu Yiling , Zheng Zhong , Huang Shanqing , Liang Dianyi , Dong He , Guo Ye , Lin Li , Song Jia , Zhang Huimin , Zheng Junhua , Zhu Zhi , Yang Chaoyong
Published: November 2023

High-throughput single-cell RNA sequencing (scRNA-seq) is recognized as a powerful technology for disentangling the heterogeneity of cellular states. However, the Poisson-dependent cell capture and low sensitivity in scRNA-seq methods pose challenges for throughput and for samples with low RNA-content. Herein, to address these challenges, we developed Well-Paired-Seq2 (WPS2) based on size-exclusion and locally quasi-static hydrodynamic principles to realize high efficiency of cell utilization, single cell/bead pairing, and cell-free RNA removal. WPS2 exploits molecular crowding effect, tailing activity enhancement in reverse transcription, and homogeneous enzymatic reaction in the initial bead-based amplification to achieve 3116 genes and 8447 transcripts. With an average of ∼20,000 reads per cell, WPS2 detected 1420 more genes and 4864 more transcripts than our previous Well-Paired-Seq. Using WPS2, we overcame the Poisson limit for the capture of both cells and beads and accurately characterized transcriptomes of low RNA-content single cells and nuclei with high sensitivity. WPS2 was further applied to comprehensively profile transcriptomes from frozen clinical samples. We found that clear cell renal cell carcinoma (ccRCC) has a complex microenvironment, and that chromophobe renal cell carcinoma (chRCC) exhibits abundant copy number variations (CNVs). In addition, metanephric adenoma (MA) was characterized at single-cell level for the first time and some potentially specific markers were revealed. With the advantages of high sensitivity, high throughput, and high fidelity, we anticipate that WPS2 will be broadly applicable in basic and clinical research.
Evaluating the performance of protein structure prediction in detecting structural changes of pathogenic nonsynonymous single nucleotide variants
Authors: Lai Hong-Sheng , Chen Chien-Yu
Published: November 2023

Abstract

Protein structure prediction serves as an efficient tool, saving time and circumventing the need for laborious experimental endeavors. Distinguished methodologies, including AlphaFold, RoseTTAFold, and ESMFold, have proven their precision through rigorous evaluation based on the last Critical Assessment of Protein Structure Prediction (CASP14). The success of protein structure prediction raises the following question: can the prediction tools discern structural alterations resulting from single amino acid changes? In this regard, the objective of this study is to assess the performance of existing structure prediction tools on mutated sequences. In this study, we posited that a specific fraction of the pathogenic nonsynonymous single nucleotide variants (nsSNVs) would experience structural alterations following amino acid mutations. We meticulously assembled an extensive dataset by initially sourcing data from ClinVar and subsequently applying multiple filters, resulting in 964 alternative sequences and their corresponding reference sequences. Utilizing UniProt, we acquired reference sequences and generated the corresponding alternative sequences based on variant information. This study performed three tools of structure prediction on both the reference and alternative sequences and expected some structural changes upon mutations. Our findings affirm AlphaFold as the foremost prediction tool presently; nonetheless, our experimental results underscore persistent challenges in accurately predicting structural alterations induced by nsSNVs. Discrepancies between the predicted structures of reference and alternative sequences, when observed, often stem from a lack of confidence in the predictions or the spatial separation between compact domains interrupted by disordered regions, posing challenges to successful alignment.
Formation of recurring transient Ca2+-based intercellular communities duringDrosophilahematopoiesis
Authors: David Saar Ben , Ho Kevin Y.L. , Tanentzapf Guy , Zaritsky Assaf
Published: November 2023

Tissue development occurs through a complex interplay between many individual cells. Yet, the fundamental question of how collective tissue behavior emerges from heterogeneous and noisy information processing and transfer at the single-cell level remains unknown. Here, we reveal that tissue scale signaling regulation can arise from local gap-junction mediated cell-cell signaling through the spatiotemporal establishment of an intermediate-scale of transient multicellular communication communities over the course of tissue development. We demonstrated this intermediate scale of emergent signaling using Ca2+signaling in the intact, ex vivo cultured, live developingDrosophilahematopoietic organ, the Lymph Gland (LG). Recurrent activation of these transient signaling communities defined self-organized signaling “hotspots” that receive and transmit information to facilitate repetitive interactions with non-hotspot neighbors, transfer information across cells, and regulate the developmental progression of hotspots. Overall, this work bridges the scales between single-cell and emergent group behavior providing key mechanistic insight into how cells establish tissue-scale communication networks.

Significance statement

Cells coordinate their internal state and behavior by exchanging information with other cells in their vicinity. These local interactions are integrated across space and time to enable synchronized function at the tissue scale. Using live microscopy imaging of theDrosophilaLymph Gland, and by applying computational analyses, we identified and characterized a new mode of cellular communication through self-organized recurring coordinated short-term activation at the intermediate scale of 3-8 cells, which we call “hotspots”. We reveal that hotspots form over the course of tissue development, and are dependent on specific proteins, called gap-junctions, that enable communication between adjacent cells. Hotspots repeatedly transmit and retrieve information to and from their non-hotspot neighbors to spread information throughout the tissue to regulate and coordinate tissue function.
Influence of rifampicin-resistance mutations on the synthesis of antioxidant, DNA-protective, and SOS-inhibitory metabolites
Authors: Statsenko V.N. , Prazdnova E.V.
Published: November 2023

This work is aimed at studying the effects of rifampicin resistance mutations on the synthesis of secondary metabolites with antioxidant and DNA-protective properties.

We used probiotic strains of the genusBacillus:B. amyloliquefaciensB-1895 andB. subtilisKATMIRA1933.

The antioxidant, DNA-protective activity, and the ability to suppress the SOS-response inB. amyloliquefaciensB-1895 andB. subtilisKATMIRA1933 rifampicin-resistant mutants have been studied for the first time. It has been found that antioxidant, DNA protective, and SOS-inhibiting activity is higher in rifampicin-resistant mutants than that of original strains.

According to the study results, it has been discovered that the antioxidant, DNA-protective and SOS-inhibitory activity in mutantsB. amyloliquefaciensB-1895 andB. subtilisKATMIRA1933 resistant to rifampicin is higher than in control strains, which indirectly proves the pleiotropic effect of therpoBgene on these activities.
Connectivity underlying motor cortex activity during naturalistic goal-directed behavior
Authors: Finkelstein Arseny , Daie Kayvon , Rózsa Márton , Darshan Ran , Svoboda Karel
Published: November 2023

Neural representations of information are shaped by local network interactions. Previous studies linking neural coding and cortical connectivity focused on stimulus selectivity in the sensory cortex1–4. Here we study neural activity in the motor cortex during naturalistic behavior in which mice gathered rewards with multidirectional tongue reaching. This behavior does not require training and thus allowed us to probe neural coding and connectivity in motor cortex before its activity is shaped by learning a specific task. Neurons typically responded during and after reaching movements and exhibited conjunctive tuning to target location and reward outcome. We used an all-optical5,4,6,7method for large-scale causal functional connectivity mappingin vivo. Mapping connectivity between > 20,000,000 excitatory neuronal pairs revealed fine-scale columnar architecture in layer 2/3 of the motor cortex. Neurons displayed local (< 100 µm) like-to-like connectivity according to target-location tuning, and inhibition over longer spatial scales. Connectivity patterns comprised a continuum, with abundant weakly connected neurons and sparse strongly connected neurons that function as network hubs. Hub neurons were weakly tuned to target-location and reward-outcome but strongly influenced neighboring neurons. This network of neurons, encoding location and outcome of movements to different motor goals, may be a general substrate for rapid learning of complex, goal-directed behaviors.
CK-666 and CK-869 differentially inhibit Arp2/3 iso-complexes
Authors: Cao LuYan , Huang Shaina , Basant Angika , Mladenov Miroslav , Way Michael
Published: November 2023

The inhibitors, CK-666 and CK-869, are widely used to probe the function of actin nucleation by the Arp2/3 complexin vitroand in cells. However, in mammals, the Arp2/3 complex consists of 8 iso-complexes, as three of its subunits (Arp3, ArpC1, ArpC5) are encoded by two different genes. Here, we used recombinant Arp2/3 with defined composition to assess the activity of CK-666 and CK-869 against iso-complexes. We demonstrate that both inhibitors prevent linear actin filament formation when ArpC1A- or ArpC1B-containing complexes are activated by SPIN90. In contrast, inhibition of actin branching depends on iso-complex composition. Both drugs prevent actin branch formation by complexes containing ArpC1A, but only CK-869 can inhibit ArpC1B-containing complexes. Consistent with this, in bone marrow-derived macrophages which express low levels of ArpC1A, CK-869 but not CK-666, impacted phagocytosis and cell migration. CK-869 is also only able to inhibit Arp3-but not Arp3B-containing iso-complexes. Our findings have important implications for the interpretation of results using CK-666 and CK-869, given that the relative expression levels of ArpC1 and Arp3 isoforms in cells and tissues remains largely unknown.
Cyperus babakan Steud. (Liliopsida: Poales: Cyperaceae), a new record for southern India
Authors: B.S. Anakha  , A.R. Viji
Published: November 2023

Cyperus babakan Steud. is reported here for the first time from southern India based on the collection made from Kerala, India. Descriptions, images of the species, distribution and phenology  are provided here.
Diversity and Distribution of Birds in the Bharathapuzha river basin, Kerala, India
Authors: P.N. Anoop Raj  , A.D. Velankar  , P. Pramod
Published: November 2023

Bharathapuzha River is the second largest, west-flowing river in Kerala, Western Ghats. This river is exposed to high levels of anthropogenic and natural pressures. This study attempts to understand the diversity and distribution of birds in this river basin. The observations were made from October 2017 to July 2019 in 70*1 km2 grids distributed in three strata (i.e., upper, middle, and lower reaches). A total of 262 bird species were recorded from the river basin. The diversity and richness of birds were found high in the upper reaches of the river and the species abundance was found more in the lower reaches. Due to the high turnover of migratory species, the rank abundance model for upper and lower reaches showed a high degree of dominance while middle reaches showed a relatively even distribution of abundances. Deforestation, sand mining, and water pollution were found to be the major threats in the river basin. Hence the results show the importance of the protection and rejuvenation of the ecosystems associated with the river for the conservation of avian diversity in the region.