Longer Operative Time Results in a Higher Rate of Subsequent Periprosthetic Joint Infection in Patients Undergoing Primary Joint Arthroplasty

Background

Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA.

Immune checkpoint inhibitor-induced inflammatory arthritis: identification and management

ABSTRACT

Introduction

Immune checkpoint inhibitors (ICIs) have proved to be groundbreaking in the field of oncology. However, immune system overactivation from ICIs has introduced a novel medical entity known as immune-related adverse events (irAEs), that can affect any organ or tissue. ICI-induced inflammatory arthritis (ICI-IIA) is the most common musculoskeletal irAE and can lead to significant morbidity and limitation in anti-cancer therapy.     

Peak bone mass of Iranian population: the Iranian Multicenter Osteoporosis Study.

Osteoporosis is a major public health problem in the Western countries and is projected to have a similar impact in the Middle East. It has been suggested that peak bone mineral density (BMD), a major determinant of osteoporotic fractures later in life, may be lower in this part of the world compared with the Western world. The purpose of the Iranian Multicenter Osteoporosis Study was to determine peak bone mass in a randomly chosen sample of healthy Iranian subjects. A total of 5201 participants (2340 males, mean age 42.7+/-13.8) were recruited based on randomized clustered sampling from all regions of five major cities across the country. In women, peak lumbar BMD (1.182+/-0.127 g/cm2) occurred in the 29- to 33-yr age group, whereas peak total femur BMD (1.006+/-0.126 g/cm2) occurred in the 32- to 36-yr age group. In men, peak lumbar BMD (1.181+/-0.153 g/cm2) and femoral BMD (1.096+/-0.159 g/cm2) both occurred in the 20- to 24-yr age group. When standardized to mg/cm2 units using established formulas, Iranian peak bone mass values are comparable with that of Western countries and are generally higher than that of Eastern Asian and Middle Eastern countries.     

Tolerance of ocular iontophoresis in healthy volunteers.

To evaluate ocular tolerance, healthy volunteers were iontophoresed transclerally using novel OcuPhor trade mark hydrogel drug delivery applicators filled with balanced salt solution. In this three-period crossover study in 24 male and female subjects, 16 subjects received 0 mA and two of the following DC currents: 0.1, 0.5., 1.0, 2.0, 3.0, or 4.0 mA for 20 min; 6 subjects received 3 mA for 20 min and 1.5 mA for 40 min (both equivalent to 60 mAmin total charge). Safety and tolerance were determined by subjective VAS and objective ophthalmic assessments. Subjects were evaluated before and up to 22 hr after dosing. The applicators were well-tolerated and no clinically significant changes in symptomology or in ophthalmic assessments were seen following exposure to 0-3.0 mA for 20 min or 1.5 mA for 40 min. At 4.0 mA 2 of 4 subjects reported a burning sensation under the applicator during dosing which resolved by 22 hr post-dose; superficial changes in fluorescein staining were observed at 1 hr, but not at 22 hr. The OcuPhor trade mark system has promise for noninvasive drug delivery to the eye.     

Relationship between pregnancy outcomes and maternal vitamin D and calcium intake: A cross-sectional study.

Poor maternal vitamin D status affects fetal and infant skeletal growth. The aim of the present study was to determine the association between newborn outcomes and maternal calcium and vitamin D intakes. Four hundred and forty-nine pregnant women, healthy at the point of delivery, and their newborns were enrolled in the study, which was performed in three university hospitals in Tehran in March 2004. Maternal anthropometric data and energy, protein, calcium and vitamin D intakes were collected, and newborn outcomes (weight, length, head circumference and 1-min Apgar score) were determined. Almost two-thirds of the mothers (64.3%) took no supplements during pregnancy. Only one-third of the mothers (33.8%) had adequate intakes of calcium and vitamin D (from supplements and foods) compared with the Recommended Dietary Allowances. Mean length at birth and 1-min Apgar score were higher in newborns whose mothers had adequate calcium and vitamin D intake than in newborns whose mothers had inadequate intake (p = 0.03 and p = 0.04, respectively). Significant correlations were found between adequate maternal calcium and vitamin D intake and both appropriate birth weight and 1-min Apgar score of newborns and weight gain of mothers during pregnancy. Informing mothers of the critical importance of consuming adequate amounts of calcium and vitamin D seems necessary.     

Activation of Classical Complement Pathway by Naturally Occurring Heteroantibodies in Normal Rabbit Serum. Effect on Subpopulations of Human Lymphoid Cells

Heteroantibodies present in normal rabbit serum (NRS) are toxic to human B lymphocytes, T lymphocytes, and monocytes. Even NRS, which exhibits little back ground cytotoxicity for human lymphoid cells in conventional HLA or B-cell lymphocytotoxic assays, can be shown to contain considerable activity by making two modifications in usual procedures: by washing cells in saline or balanced salt solutions devoid of protein or sugar substances, and by increasing incubation time for 1 h to 3--4 h. Using such modifications, the cytotoxic activity of NRS towards human lymphoid cells was investigated and was found to involve activation of the classical complement pathway rather than activation of the alternate complement pathway. Residual unwanted background cytotoxicity of NRS toward human lymphoid cells can be decreased without loss of desired complement activity either by heating NRS for 15 min at 50 degrees C or by mixing NRS with small amounts of normal human serum.     

Thymus involution in the acquired immunodeficiency syndrome

Acquired immunodeficiency syndrome (AIDS) is a severe disorder of unknown etiology and pathogenesis, predominantly affecting homosexual males and other high-risk groups and characterized by profound alterations in T-lymphocyte function. The authors have examined thymus tissue from 14 patients who died of AIDS and compared the results with findings in five control groups: healthy age-matched controls, elderly individuals, patients with chronic or debilitating illnesses other than AIDS, infants with conditions causing "stress atrophy," and patients with myasthenia gravis. The AIDS group included 11 homosexual males, 1 Haitian, 1 homosexual who was also a drug abuser, and a 10-month-old infant believed to have contracted AIDS following blood transfusion. All the AIDS cases showed marked thymus involution with severe depletion of both lymphocytes and epithelial elements. The latter component consisted primarily of thin cords and nests of primitive-appearing epithelial cells that could be defined by positive immunohistochemical staining for keratin. Many cases showed a variable plasma cell infiltration, and the majority exhibited distinct vascular changes in the form of hyalinization and/or onion-skin patterns, primarily in the adventitia. Most striking of all was the marked paucity of Hassall's corpuscles; four patients had none at all, while in the other ten patients all the Hassall's corpuscles were calcified. These changes were far more extensive than those seen in any of the control groups, which retained most of their complement of Hassall's corpuscles even in the face of marked overall involution. The physiologic function of Hassall's corpuscles is not known, but recent immunohistochemical studies have implicated them in the synthesis of "facteur thymique serique" (FTS, thymulin) and other thymic hormones known to play a role in regulating T-helper and suppressor cell activity. It is conceivable that the extensive destruction of Hassall's corpuscles observed in AIDS may be a crucial element in the pathogenesis of this syndrome.     

Inspiratory activation is not required for episodic hypoxia-induced respiratory long-term facilitation in postnatal rats

Episodic hypoxia causes repetitive inspiratory activation that induces a form of respiratory plasticity termed long-term facilitation (LTF). While LTF is a function of the hypoxic exposures and inspiratory activation, their relative importance in evoking LTF is unknown. The aims of this study were to: (1) dissociate the relative roles played by episodic hypoxia and respiratory activation in LTF; and (2) determine whether the magnitude of LTF varies as a function of hypoxic intensity. We did this by examining the effects of episodic hypoxia in postnatal rats (15–25 days old), which unlike adult rats exhibit a prominent hypoxia-induced respiratory depression. We quantified inspiratory phrenic nerve activity generated by the in situ working-heart brainstem before, during and for 60 min after episodic hypoxia. We demonstrate that episodic hypoxia evokes LTF despite the fact that it potently suppresses inspiratory activity during individual hypoxic exposures ( P < 0.05). Specifically, we show that after episodic hypoxia (three 5 min periods of 10% O₂) respiratory frequency increased to 40 ± 3.3% above baseline values over the next 60 min ( P < 0.001). Continuous hypoxia (15 min of 10% O₂) had no lasting effects on respiratory frequency ( P > 0.05). To determine if LTF magnitude was affected by hypoxic intensity, the episodic hypoxia protocol was repeated under three different O₂ tensions. We demonstrate that the magnitude and time course of LTF depend on hypoxic severity, with more intense hypoxia inducing a more potent degree of LTF. We conclude that inspiratory activation is not required for LTF induction, and that hypoxia per se is the physiological stimulus for eliciting hypoxia-induced respiratory LTF.     

Effectiveness of telephone-based screening and triage during COVID-19 outbreak in the promoted primary healthcare system: a case study in Ardabil province,Iran

Journal of Public Health - Screening services for early detection of patients is one of the important capabilities of the health system with a proper referral system. In the crisis of respiratory...