The Assembly of HTLV-1-How Does It Differ from HIV-1?

Retroviral assembly is a highly coordinated step in the replication cycle. The process is initiated when the newly synthesized Gag and Gag-Pol polyproteins are directed to the inner leaflet of the plasma membrane (PM), where they facilitate the budding and release of immature viral particles. Extensive research over the years has provided crucial insights into the molecular determinants of this assembly step.

Academy for Quality and Safety Improvement (AQSI) project to improve diagnosis and documentation of malnutrition in a community hospital.

Background: Malnutrition is a significant public health problem that affects many patients in inpatient settings. Timely identification and addressing malnutrition in an inpatient setting presents an opportunity to improve patient care and reduce costs. There is a clear link between malnutrition, increased length of hospital stay, higher risk of readmissions and infections, skin breakdown, and higher hospital costs due to complications.

Novel pneumococcal capsule type 33E results from the inactivation of glycosyltransferase WciE in vaccine type 33F.

The polysaccharide (PS) capsule is essential for immune evasion and virulence of Streptococcus pneumoniae. Existing pneumococcal vaccines are designed to elicit anticapsule antibodies; however, the effectiveness of these vaccines is being challenged by the emergence of new capsule types or variants. Herein, we characterize a newly discovered capsule type, 33E, that appears to have repeatedly emerged from vaccine type 33F via an inactivation mutation in the capsule glycosyltransferase gene, wciE.

Discovery and Characterization of Pneumococcal Serogroup 36 Capsule Subtypes, Serotypes 36A and 36B.

Streptococcus pneumoniae can produce a wide breadth of antigenically diverse capsule types, a fact that poses a looming threat to the success of vaccines that target pneumococcal polysaccharide (PS) capsule. Yet, many pneumococcal capsule types remain undiscovered and/or uncharacterized. Prior sequence analysis of pneumococcal capsule synthesis () loci suggested the existence of capsule subtypes among isolates identified as "serotype 36" according to conventional capsule typing methods.

Structural Insights into the Mechanism of HIV-1 Tat Secretion from the Plasma Membrane.

Human immunodeficiency virus type 1 (HIV-1) trans-activator of transcription (Tat) is a small, intrinsically disordered basic protein that plays diverse roles in the HIV-1 replication cycle, including promotion of efficient viral RNA transcription. Tat is released by infected cells and subsequently absorbed by healthy cells, thereby contributing to HIV-1 pathogenesis including HIV-associated neurocognitive disorder. It has been shown that, in HIV-1-infected primary CD4 T-cells, Tat accumulates at the plasma membrane (PM) for secretion, a mechanism mediated by phosphatidylinositol 4,5-bisphosphate (PI(4,5)P).

Atomic view of the HIV-1 matrix lattice; implications on virus assembly and envelope incorporation.

During the late phase of HIV type 1 (HIV-1) infection cycle, the virally encoded Gag polyproteins are targeted to the inner leaflet of the plasma membrane (PM) for assembly, formation of immature particles, and virus release. Gag binding to the PM is mediated by interactions of the N-terminally myristoylated matrix (myrMA) domain with phosphatidylinositol 4,5-bisphosphate. Formation of a myrMA lattice on the PM is an obligatory step for the assembly of immature HIV-1 particles and envelope (Env) incorporation.

Molecular Determinants of Human T-cell Leukemia Virus Type 1 Gag Targeting to the Plasma Membrane for Assembly.

Assembly of human T-cell leukemia virus type 1 (HTLV-1) particles is initiated by the trafficking of virally encoded Gag polyproteins to the inner leaflet of the plasma membrane (PM). Gag-PM interactions are mediated by the matrix (MA) domain, which contains a myristoyl group (myr) and a basic patch formed by lysine and arginine residues. For many retroviruses, Gag-PM interactions are mediated by phosphatidylinositol 4,5-bisphosphate [PI(4,5)P]; however, previous studies suggested that HTLV-1 Gag-PM interactions and therefore virus assembly are less dependent on PI(4,5)P.

A periplasmic cinched protein is required for siderophore secretion and virulence of Mycobacterium tuberculosis.

Iron is essential for growth of Mycobacterium tuberculosis, the causative agent of tuberculosis. To acquire iron from the host, M. tuberculosis uses the siderophores called mycobactins and carboxymycobactins.

A 58-Year-Old Woman with Gallstones, Chronic Pancreatitis, and Pancreatic Pseudocyst Presenting with Pleural Effusion Due to a Pancreaticopleural Fistula.

BACKGROUND Pancreaticopleural fistula (PPF) is a rare complication of acute and chronic pancreatitis. PPF results from the release of pancreatic enzymes, either from a damaged pancreatic duct or pancreatic pseudocyst. This report is of a 58-year-old woman with a history of chronic pancreatitis associated with gallstones who had a known pancreatic pseudocyst that was being managed conservatively and who presented to the Emergency Department with pleural effusion due to a PPF.

Hypercalcaemia Caused by Sunflower Seeds and Calcium Carbonate Supplements.

Introduction: Hypercalcaemia is commonly associated with malignancy or endocrinological disorders. However, sometimes it can occur due to increased oral intake of calcium. We present an interesting case of hypercalcaemia due to ingestion of sunflower seeds and calcium carbonate supplements.

Anatomical Site-Specific Carbohydrate Availability Impacts Streptococcus pneumoniae Virulence and Fitness during Colonization and Disease.

Streptococcus pneumoniae colonizes the nasopharynx asymptomatically but can also cause severe life-threatening disease. Importantly, stark differences in carbohydrate availability exist between the nasopharynx and invasive disease sites, such as the bloodstream, which most likely impact S. pneumoniae's behavior.

A Case of Evans Syndrome and Unstable Angina.

Evans syndrome (ES) is characterized by autoimmune hemolytic anemia (AIHA) and immune-mediated thrombocytopenia. It is more common in the pediatric population than in adults. ES has been reported to be associated with thrombotic events and rarely can lead to acute coronary syndrome (ACS).

Capsule Promotes Intracellular Survival and Vascular Endothelial Cell Translocation during Invasive Pneumococcal Disease.

The polysaccharide capsule that surrounds Streptococcus pneumoniae () is one of its most important virulence determinants, serving to protect against phagocytosis. To date, 100 biochemical and antigenically distinct capsule types, i.e.

An Interesting Case of Critical Spontaneous Ureteral Rupture.

Spontaneous rupture of the ureter in an uncommon presentation. We present a case of an 85-year-old female patient with a past medical history significant for hypertension and hyperlipidemia who presented to the emergency room (ER) due to abdominal pain and nausea. Computed tomography (CT) of abdomen and pelvis revealed proximal ureteral and ureteropelvic junction rupture with fluid within the left retroperitoneum and pelvis.

Structural Insights into the Mechanism of Human T-cell Leukemia Virus Type 1 Gag Targeting to the Plasma Membrane for Assembly.

Retroviral Gag targeting to the plasma membrane (PM) for assembly is mediated by the N-terminal matrix (MA) domain. For many retroviruses, Gag-PM interaction is dependent on phosphatidylinositol 4,5-bisphosphate (PI(4,5)P). However, it has been shown that for human T-cell leukemia virus type 1 (HTLV-1), Gag binding to membranes is less dependent on PI(4,5)P than HIV-1, suggesting that other factors may modulate Gag assembly.

Pancoast-Tobias Syndrome: A Unique Presentation of Lung Cancer.

A 65-year-old man with 50 pack-year smoking history presented to the emergency department for evaluation of upper back and right shoulder pain secondary to a fall. Physical examination was notable for anisocoria with a constricted left pupil (miosis), mild ptosis of the left eyelid, and bilateral shoulder pain, right more than left, with both passive and active movements. Chest computed tomography identified a soft tissue mass at the left lung apex with extension into the pleural surface, associated with destructive osseous changes of the right scapula, adjacent ribs, and thoracic vertebral bodies.

Structural characterization of HIV-1 matrix mutants implicated in envelope incorporation.

During the late phase of HIV-1 infection, viral Gag polyproteins are targeted to the plasma membrane (PM) for assembly. Gag localization at the PM is a prerequisite for the incorporation of the envelope protein (Env) into budding particles. Gag assembly and Env incorporation are mediated by the N-terminal myristoylated matrix (MA) domain of Gag.

A New Pneumococcal Capsule Type, 10D, is the 100th Serotype and Has a Large Fragment from an Oral Streptococcus.

(pneumococcus) is a major human pathogen producing structurally diverse capsular polysaccharides. Widespread use of highly successful pneumococcal conjugate vaccines (PCVs) targeting pneumococcal capsules has greatly reduced infections by the vaccine types but increased infections by nonvaccine serotypes. Herein, we report a new and the 100th capsule type, named serotype 10D, by determining its unique chemical structure and biosynthetic roles of all capsule synthesis locus () genes.

The Interplay between HIV-1 Gag Binding to the Plasma Membrane and Env Incorporation.

Advancement in drug therapies and patient care have drastically improved the mortality rates of HIV-1 infected individuals. Many of these therapies were developed or improved upon by using structure-based techniques, which underscore the importance of understanding essential mechanisms in the replication cycle of HIV-1 at the structural level. One such process which remains poorly understood is the incorporation of the envelope glycoprotein (Env) into budding virus particles.

Structural and biophysical characterizations of HIV-1 matrix trimer binding to lipid nanodiscs shed light on virus assembly.

During the late phase of the HIV-1 replication cycle, the viral Gag polyproteins are targeted to the plasma membrane for assembly. The Gag-membrane interaction is mediated by binding of Gag's N-terminal myristoylated matrix (MA) domain to phosphatidylinositol 4,5-bisphosphate (PI(4,5)P). The viral envelope (Env) glycoprotein is then recruited to the assembly sites and incorporated into budding particles.

Pneumococci Can Become Virulent by Acquiring a New Capsule From Oral Streptococci.

Pneumococcal conjugate vaccines have been successful, but their use has increased infections by nonvaccine serotypes. Oral streptococci often harbor capsular polysaccharide (PS) synthesis loci (cps). Although this has not been observed in nature, if pneumococcus can replace its cps with oral streptococcal cps, it may increase its serotype repertoire.

Implications of Left Bundle Branch Block in Takotsubo Cardiomyopathy: Propensity Match Analysis from the National Inpatient Sample.

Introduction: Takotsubo cardiomyopathy (TTC), also called stress cardiomyopathy, is a transient reversible left ventricular dysfunction mimicking acute coronary syndrome (ACS). Studies have shown similar rates of in-hospital complications in TTC and myocardial infarction (MI). Left bundle branch block (LBBB) is associated with increased mortality in patients with MI; however, similar studies comparing outcomes of TTC in the presence of LBBB are lacking.