The bacterial nucleoid-associated proteins, HU and Dps, condense DNA into context-dependent biphasic or multiphasic complex coacervates.

The bacterial chromosome, known as its nucleoid, is an amorphous assemblage of globular nucleoprotein domains. It exists in a state of phase separation from the cell's cytoplasm, as an irregularly-shaped, membrane-less, intracellular compartment. This state (the nature of which remains largely unknown) is maintained through bacterial generations ad infinitum. Here, we show that HU and Dps, two of the most abundant nucleoid-associated proteins (NAPs) of Escherichia coli, undergo spontaneous complex coacervation with different forms of DNA/RNA, both individually and in each other's presence, to cause accretion and compaction of DNA/RNA into liquid-liquid phase separated condensates in vitro. Upon mixing with nucleic acids, HU-A and HU-B form (a) biphasic heterotypic mixed condensates in which HU-B helps to lower the Csat of HU-A and also (b) multiphasic heterotypic condensates, with Dps, in which demixed domains display different contents of HU and Dps. We believe that these modes of complex coacervation that are seen in vitro can serve as models for the in vivo relationships among NAPs in nucleoids, involving local and global variations in the relative abundances of the different NAPs, especially in demixed subdomains that are characterized by differing grades of phase separation. Our results clearly demonstrate some quantitative, and some qualitative, differences in the coacervating abilities of different NAPs with DNA, potentially explaining (i) why E. coli has two isoforms of HU, and (ii) why changes in the abundances of HU and Dps facilitate the lag, logarithmic, and stationary phases of E. coli growth.

The DNA-binding protein HU is a molecular glue that attaches bacteria to extracellular DNA in biofilms.

In biofilms, bacteria that possess a negatively charged surface are embedded within a matrix of polymers consisting mainly of negatively charged extracellular DNA (e-DNA). In all likelihood, a multivalent positively charged substance, for example, a basic protein, exists within biofilms to neutralize charge-charge repulsions and act as a 'glue' attaching negatively charged bacteria to negatively charged e-DNA; however, no protein capable of doing so has yet been identified. We decided to investigate whether a highly abundant nucleoid-associated histone-like protein (HU) happens to be the glue in question. In recent years, HU has been shown to possess qualities that could be considered desirable in the proposed glue, for example, (a) availability in association with e-DNA; (b) multivalent DNA binding; (c) non-sequence-specific DNA-binding; (d) enhancement of biofilm formation upon exogenous addition, and (e) disruption of biofilms, upon removal by HU-cognate antibodies. Geometric considerations suggest that basic residues in HU's canonical and noncanonical DNA-binding sites can interact with sugar-linked terminal phosphates in lipopolysaccharide (LPS) molecules in bacterial outer membranes. Here, using genetic, spectroscopic, biophysical-chemical, microscopy-based, and cytometry-based experiments, we demonstrate that HU's DNA-binding sites also bind to LPS, that this facilitates DNA-DNA, DNA-LPS, and LPS-LPS interactions, and that this facilitates bacterial clumping and attachment of bacteria to DNA. Exogenous addition of HU to bacteria in (nonshaken) cultures is shown to cause cells to become engulfed in a matrix of DNA, potentially arising from the lysis of bacteria with vulnerable cell walls (as they strain to grow, divide, and move away from each other, in opposition to the accreting influence of HUs).

HU-AB simulacrum: Fusion of HU-B and HU-A into HU-B-A, a functional analog of the Escherichia coli HU-AB heterodimer.

In enteric bacteria such as Escherichia coli, there are two homologs of the DNA-binding nucleoid associated protein (NAP) known as HU. The two homologs are known as HU-A and HU-B, and exist either in the form of homodimers (HU-AA, or HU-BB) or as heterodimers (HU-AB), with different propensities to form higher-order oligomers. The three different dimeric forms dominate different stages of bacterial growth, with the HU-AB heterodimer dominating cultures in the stationary phase. Due to similarities in their properties, and the facile equilibrium that exists between the dimeric forms, the dimers are difficult to purify away from each other. Although HU-AA and HU-BB can be purified through extensive ion-exchange chromatography, reestablishment of equilibrium interferes with the purification of the HU-AB heterodimer (which constitutes ∼90% of any population with equal numbers of HU-B and HU-A chains). Here, we report the creation of a functional analog of HU-AB that does not appear to partition to generate any minority populations of HU-AA or HU-BB. The analog was constructed through genetic fusion of the HU-B and HU-A chains into a single polypeptide (HU-B-A) with a glycine/serine-rich linker of 11 amino acids separating HU-B from HU-A, and a histidine tag at the N-terminus of HU-B. HU-B-A folds to bind 4-way junction DNA, and displays a significant tendency to form dimers (i.e., analogs of HU tetramers), and a higher thermodynamic stability than HU-BB or HU-AA, thus explaining why it dominates mixtures of HU-B and HU-A chains.

A novel protein-engineered dsDNA-binding protein (HU-Simulacrum) inspired by HU, a nucleoid-associated DNABII protein.

HU, a DNA-binding protein, has a helical N-terminal region (NTR) of ∼44 residues and a beta strand- and IDR-rich C-terminal region (CTR) of ∼46 residues. CTR binds to DNA through (i) a clasp (two arginine/lysine-rich, IDR-rich beta hairpins that bind to phosphate groups in the minor groove), (ii) a flat surface (comprising four antiparallel beta strands that abut the major groove), and (iii) a charge cluster (two lysine residues upon a short C-terminal helix). HU forms a dimer displaying extensive inter-subunit CTR-CTR contacts. A single-chain simulacrum of these contacts (HU-Simul) incorporating all DNA-binding elements was created by fusing together the CTRs of Escherichia coli HU-A and Thermus thermophilus HU. HU-Simul is monomeric, binds to dsDNA and cruciform DNA, but not to ssDNA.

Sociodemographic characteristics and aggression quotient among children in conflict with the law in India: A case-control study.

BACKGROUND: The incidence of juvenile delinquency has increased in the past decade in India and juvenile crimes are increasingly being reported. This has been attributed to many biopsychosocial factors. It is essential to understand these issues in the context of India to determine the response of acts of children in conflict with the law. We aimed to assess the sociodemographic characteristics and the aggression quotient of children in conflict with the law (juvenile delinquents) in observation homes across India and compare them with those who were not. METHODS: We did a case-control study in five juvenile homes in the cities of Hyderabad, Lucknow and Pune. Ninety inmates (74 boys, 16 girls) were included in the study. Sociodemographic characteristics and aggression quotient of children in conflict with the law were evaluated using two separate questionnaires, i.e. a sociodemographic questionnaire and the modified Buss and Perry aggression questionnaire. These were compared with a control group of similar age, sex and income status. RESULTS: All the children in conflict with the law surveyed belonged to the lower socioeconomic strata, had a significantly higher chance (p<0.05) of coming from broken homes, have addictions, jailed family members and suffered physical and sexual abuse than controls. They also scored higher on all domains of the aggression questionnaire than controls. CONCLUSION: A collection of sociodemographic attributes such as broken homes, addictions and abuse seem to have an important association with juvenile delinquency. Children in conflict with the law are also more likely to be associated with a higher aggression quotient as compared to children who were not.

Acromioclavicular Ganglion Cyst: A Rare Case Report.

Acromioclavicular ganglion cysts are uncommon, with only a limited number of cases reported in the medical literature. This case report presents a unique instance of an acromioclavicular ganglion cyst in an 81-year-old male patient, outlining the clinical presentation, diagnostic approach, and successful surgical management. The purpose of this report is to contribute to the existing body of knowledge on this rare condition and highlight the importance of accurate diagnosis and appropriate intervention.

Fixation of Gardens Type 4 Intracapsular Neck of Femur Fracture Using the GS Kulkarni Controlled Dynamic Hip Screw System.

The goal for surgical treatment of femoral neck fractures is achieving union through an anatomic reduction and stable fixation while avoiding osteonecrosis. This report describes the case of a 50-year-old male who presented with pain and swelling in his right hip and inability to bear weight over his right lower limb following a road traffic accident. The X-ray revealed a right-sided femoral neck fracture (Garden Type IV and Pauwels Type III). The patient was surgically treated with the GS Kulkarni (GSK) controlled dynamic hip screw. On follow-up, the bone healing time was 14 weeks and the patient achieved a Harris hip score of 93.65 with significant improvement.

Management of Grade Three Open Distal Humerus Intra-articular Fracture Using the BB Joshi External Fixator: A Case Study and Review of Outcomes.

Distal humeral intra-articular fractures often result in functional impairment if treated conservatively. These fractures are particularly challenging due to osteoporosis and severe comminution. A 32-year-old female with a grade three open distal humerus intra-articular fracture presented with a 5 cm x 5 cm open wound on her right elbow. The patient underwent open reduction and internal fixation (ORIF) using the BB Joshi external fixator and a local flap for skin coverage, achieving stable fixation and early mobilization. The patient regained a near-normal range of movements and adequate skin coverage of the wound at follow-up. Compared to traditional ORIF, it showed lower infection rates and comparable union rates, leading to better functional outcomes when compared with the studies reported earlier. The BB Joshi external fixator effectively treats grade three open distal humerus intra-articular fractures, minimizing complications and promoting functional recovery.

A Case of a Failed Hemiarthroplasty of the Hip Treated by an Extended Trochanteric Osteotomy.

Hip bipolar hemiarthroplasty, a widely employed surgical intervention for managing hip fractures and degenerative hip diseases, can pose significant challenges when revisions become necessary due to complications such as implant loosening, instability, or breakage. This case report presents the intricate management of a 58-year-old male who presented with worsening left hip pain a decade after undergoing hip replacement surgery. Despite a thorough preoperative assessment ruling out infection, intraoperative complexities included the necessity for extended trochanteric osteotomy (ETO) to address a broken stem and associated metallosis. Successful revision surgery was meticulously executed, incorporating techniques for implant removal, femoral shaft augmentation, and postoperative rehabilitation. The ensuing discussion explores the multifaceted aspects of failed hemiarthroplasty, emphasizing the critical roles of surgical precision, judicious patient selection, and ongoing research endeavors aimed at refining surgical strategies to optimize patient outcomes. This case underscores the imperative of a multidisciplinary approach and the continued imperative for advancements in surgical methodologies for effectively managing revision hip arthroplasty cases, thus enhancing the quality of patient care in this intricate clinical domain.

Fixation of Paediatric Proximal Humerus Fractures Using Percutaneous Pinning: A Case Report.

A 12-year-old male came to our Emergency Department with chief complaints of pain and inability to move the right shoulder for one day following a fall while playing. The range of motion of the right shoulder was restricted and painful in all directions. Initial radiographs revealed a transverse, displaced proximal humerus fracture at the head-shaft junction. The patient was managed by closed reduction internal fixation with percutaneous K-wiring (Kirschner wires). The K-wires were removed after four weeks, and the shoulder was mobilized. The patient had a near-normal and pain-free range of motion at three months of follow-up. Percutaneous K-wiring remains a viable option for the treatment of paediatric proximal humerus fractures, and good post-operative rehabilitation can help restore near-normal function, as demonstrated in this report.

An Unusual Pattern of Scapular Avulsion Fracture in the Spine: A Case Study.

Acromion fractures, particularly isolated cases, are uncommon but significant in shoulder injuries. There is no universally accepted treatment protocol, but the classification of the fracture helps to guide clinical decisions. We present a case report aiming to contribute to the understanding of treatment options for acromion fractures. A 22-year-old male sustained a left shoulder injury during a wrestling match, resulting in a type 2 acromion fracture. Conservative treatment was initiated with regular follow-ups. Serial imaging showed no further displacement. Gradual rehabilitation exercises were introduced based on healing progress. The rarity of isolated acromion fractures complicates their management. Conservative management, coupled with rehabilitation exercises, yielded positive outcomes in our case, suggesting its efficacy as a primary treatment option for isolated displaced acromion fractures. Further research is needed to establish standardized protocols for managing such fractures, but until then, conservative care remains a viable approach, potentially preferred over surgical intervention.

Inferior Pole of the Patella Fracture Fixed by Percutaneous Approach: A Case Report.

Fractures of the inferior pole of the patella are rare but challenging orthopedic injuries. This case study presents the management of such a fracture using a percutaneous approach. A 70-year-old female patient presented with significant knee pain and swelling following a fall. Radiographic examination revealed a displaced fracture of the inferior pole of the patella along with an ipsilateral tibial plateau fracture. Surgical intervention was deemed necessary due to the extent of displacement and the potential for compromised knee function. A percutaneous technique was employed for fracture reduction and fixation using cannulated screws under fluoroscopic guidance. Postoperative rehabilitation focused on early mobilization and strengthening exercises. At a six-week follow-up, the patient demonstrated satisfactory clinical outcomes with restoration of knee function and minimal residual symptoms. This case highlights the efficacy of percutaneous fixation in managing inferior pole patellar fractures, offering a minimally invasive approach with favorable functional outcomes.

A Glomus Tumor Presenting on the Ventromedial Aspect of the Little Finger Causing Bony Erosion: A Rare Case From India.

Glomus tumors are rare neoplasms originating from the glomus body that predominantly manifest in the subungual region of the digits and are distinguished by severe pain and a heightened sensitivity to cold. Bony erosion associated with glomus tumors is a rare phenomenon. Here, we present a unique case of a glomus tumor situated on the ventromedial aspect of the little finger, leading to notable bony erosion. A 42-year-old female from India presented with a chief complaint of severe and localized pain in the ventromedial region of her right little finger, exacerbated by exposure to cold temperatures. Radiological investigations demonstrated focal bone erosion at the site of the tumor. Surgical excision of the lesion was performed. A fish-mouth incision was made on the ventromedial aspect of the little finger, which was extended to the tip of the finger. The nail bed was kept intact. The tumor was excised using small forceps. The patient experienced complete resolution of symptoms postoperatively and reported no recurrence during the follow-up period. This case report highlights the exceptional presentation of a glomus tumor causing bony erosion on the ventromedial aspect of the little finger, a manifestation rarely encountered in clinical practice. Furthermore, this case contributes to the limited body of literature on this combination of uncommon clinical entities, shedding light on its diagnosis and management.

Avoidance of the use of tryptophan in buried chromosomal proteins as a mechanism for reducing photo/oxidative damage to genomes.

In cells that are exposed to terrestrial sunlight, the indole moiety in the side chain of tryptophan (Trp) can suffer photo/oxidative damage (POD) by reactive oxygen species (ROS) and/or ultraviolet light (UV-B). Trp is oxidized to produce N-formylkynurenine (NFK), a UV-A-responsive photosensitizer that further degenerates into photosensitizers capable of generating ROS through exposure to visible light. Thus, Trp-containing proteins function as both victims, and perpetrators, of POD if they are not rapidly replaced through protein turnover. The literature indicates that protein turnover and DNA repair occur poorly in chromosomal interiors. We contend, therefore, that basic chromosomal proteins (BCPs) that are enveloped by DNA should have evolved to lack Trp residues in their amino acid sequences, since these could otherwise function as 'Trojan horse-type' DNA-damaging agents. Our global analyses of protein sequences demonstrates that BCPs consistently lack Trp residues, although DNA-binding proteins in general do not display such a lack. We employ HU-B (a wild-type, Trp-lacking bacterial BCP) and HU-B F47W (a mutant, Trp-containing form of the same bacterial BCP) to demonstrate that the possession of Trp is deleterious to BCPs and associated chromosomal DNA. Basically, we show that UV-B and UV-A (a) cause no POD in HU-B, but cause extensive POD in HU-B F47W (in vitro), as well as (b) only nominal DNA damage in bacteria expressing HU-B, but extensive DNA damage in bacteria expressing F47W HU-B (in vivo). Our results suggest that Trp-lacking BCPs could have evolved to reduce scope for protein-facilitated, sunlight-mediated damage of DNA by UV-A and visible light, within chromosomal interiors that are poorly serviced by protein turnover and DNA repair machinery.

Intraoperative Identification and Mosaicplasty in a Case of Femur Subchondral Osteoid Osteoma.

Osteoid osteomas (OOs) are non-malignant primary bone abnormalities marked by a central nidus surrounded by reactive sclerosis. They typically manifest as aggravated nocturnal pain that responds to non-steroidal anti-inflammatory drugs (NSAIDs). These growths are most frequently found within the intracortical bone and the diaphysis of elongated bones. Within the realm of uncommon conditions, intra-articular OOs (IAOOs) exhibit distinctive presentations, often leading to postponed or inaccurate diagnoses. We present a patient with OO at the distal femur, accessible through the knee joint, which was intraoperatively identified and localized using a needle pricking technique and treated by arthrotomy and mosaicplasty.

Restoring Wrist Harmony: A Case Report of Ulnar Osteotomy for Correcting the Radius Malunion.

A 41-year-old female patient sought medical attention due to a malunited distal radius fracture with a positive ulnar variance, experiencing wrist pain and limited range of motion. The patient was successfully treated with an isolated ulnar osteotomy and bone grafting, resulting in significant alleviation of symptoms and improved wrist mobility. Various surgical methods have been proposed to address malunited radius fractures, and ulnar osteotomy has shown promise as an effective technique for such cases.

Spatiotemporal Regulation of CRISPR/Cas9 Enables Efficient, Precise, and Heritable Edits in Plant Genomes.

CRISPR/Cas-mediated editing has revolutionized crop engineering. Due to the broad scope and potential of this technology, many studies have been carried out in the past decade towards optimizing genome editing constructs. Clearly, the choice of the promoter used to drive gRNA and Cas9 expression is critical to achieving high editing efficiency, precision, and heritability. While some important considerations for choosing a promoter include the number and nature of targets, host organism, mode of transformation and goal of the experiment, spatiotemporal regulation of Cas9 expression using tissue-specific or inducible promoters enables higher heritability and efficiency of targeted mutagenesis with reduced off-target effects. In this review, we discuss specific studies that highlight the prospects and trade-offs associated with the choice of promoters on genome editing and emphasize the need for inductive exploration and discovery to further advance this area of research in crop plants.

Abdominal compartment syndrome secondary to myxedema ileus.

Acute pseudo-obstruction of the colon is known as Ogilvie syndrome (OS). There are varied causes of OS. Myxedema ileus (MI) as a cause of acute pseudo-obstruction is rare. Surgery in cases of MI is reserved only in cases of cecal distension of >12 cm, bowel ischemia, and perforated bowel. We present a rare case of a 71-year-old female who was operated for abdominal compartment syndrome secondary to MI.

Intraperitoneal bladder explosion during transurethral surgery.

Transurethral resection of prostate (TURP) is the most common operation performed for obstruction secondary to prostatic enlargement. Though considered as a safe procedure, occasionally life-threatening complications may be seen. Intravesical explosion, secondary to ignition by diathermy of the accumulated mixture of hydrogen, hydrocarbons and higher concentration of oxygen, is a rarely reported complication (only 38 cases reported until). We are reporting a 60-year-old man suffering from benign prostatic hyperplasia in whom during TURP bladder explosion occurred which was suspected early and immediately explored and repaired leading to a favourable outcome.

Ruptured primary mucinous cystadenoma of spleen leading to mucinous ascites.

Mucinous cystadenoma are rare benign mucin-producing tumours. Primary mucinous neoplasms most commonly involve ovary, pancreas or appendix. They may rupture to produce mucous ascites/pseudomyxoma peritonei. We are describing a 51-year-old man who presented to us with symptomatic gallstone disease but during preoperative ultrasound was found to have cystic lesions in spleen with free fluid in the abdomen. Splenectomy and drainage of mucin were done. Histopathology was done and a final diagnosis of primary mucinous cystadenoma of spleen with mucinous ascites was made.