Implications of Heavy Metal Accumulation in Fish Feed, Water, Sediment, and Different Fish Species in a Polyculture System.

Heavy metal bioaccumulation in organisms is primarily a result of dietary uptake. The current study examines the concentrations of heavy metals (Pb, Cd, Cr, and Cu) in fish feed, water, sediment, and three fish species (Catla catla, Labeo rohita, and Cyprinus carpio) from different feeding zones in a polyculture pond system. Furthermore, associated human health risks were also evaluated. The fish samples (n = 25 for each species) were collected from 10 different fish ponds in the Kohat district, Pakistan. Heavy metals were determined using an atomic absorption spectrometer. Results revealed higher concentrations of heavy metals in sediment, followed by water. However, the concentration of heavy metals in fish feed was lower than the standard limits. In the case of fish, the bottom feeder (C. carpio) notably exhibited higher (P < 0.05) levels of heavy metals than the column feeder (L. rohita) and surface feeder (C. catla) fish. Moreover, in the liver of all fish species, the bioaccumulation of heavy metals was higher, followed by the gills. Principal component analysis (PCA) demonstrated a strong correlation of heavy metals in C. carpio gills, flesh, feed, and pond water, while the heavy metals in the liver correlated with the detected metals in sediment. The human health risk analysis shows that bottom feeder fish had higher estimated daily intake (EDI), target hazard quotient (THQ), and hazard index (HI) values (> 1). Consequently, the exposed population may experience adverse health effects. The findings of this study suggest that the bottom feeder (C. carpio) bioaccumulates a higher concentration of heavy metals than column (L. rohita) and surface feeder (C. catla) in the polyculture system.

Diagnostic Accuracy of Cerebrospinal Fluid Multiplex Polymerase Chain Reaction Panel Testing in Patients With Suspected Central Nervous System Infections: A Multi-Center Study in the United Arab Emirates.

Background Delays in diagnosis and treatment of central nervous system (CNS) infections can lead to significant morbidity and mortality among children and adults. Prior antibiotic treatment is a major hurdle to accurate diagnosis due to falsely negative cerebrospinal fluid (CSF) cultures in partially treated patients. Increasingly, molecular diagnostic methods using multiplex polymerase chain reaction (mPCR) testing on CSF samples are being utilized in clinical practice for timely and accurate diagnosis. However, there is no data regarding the diagnostic accuracy or clinical impact of CSF mPCR testing in the Middle East region. We sought to compare the diagnostic accuracy of an automated mPCR CSF panel with routine CSF culture, the current gold standard, in the United Arab Emirates (UAE).  Methods This single-gated, multi-center, diagnostic accuracy study included patients from birth onwards who were admitted to any of the three participating hospitals with an initial diagnosis of meningitis or encephalitis, between January 2017 and March 2021, and had CSF samples collected for mPCR and culture. Sociodemographic, clinical, and molecular data were collected for all. Results A total of 353 CSF samples were collected from patients from 0-90 years old hospitalized for suspected CNS infection. Children constituted 51% of the study population, and males were slightly over-represented (55.2%). Pathogens were detected by mPCR in 78 (22%) CSF samples, of which 19 (24%) were bacteria and 59 (76%) were viruses. No fungal pathogens were detected. Enteroviruses were the most prevalent CNS pathogen among our cohort (40%), followed by herpes simplex virus type 2 (HSV-2) (12.5%). Children constituted 69% of positive samples for enterovirus, while HSV-2 was exclusively detected among adults. Using CSF culture as the diagnostic gold standard, the mPCR panel demonstrated high specificity (100%) and sensitivity (96.3%) in diagnosing CNS infection among all age groups. mPCR testing demonstrated a high overall percentage of agreement (OPA) with CSF culture (98.9%). Patients with bacterial meningitis had a significantly longer hospitalization (p=0.004) and duration of antibiotic therapy (p=0.001) compared to those with viral meningitis. Three CSF samples were negative on mPCR testing but positive on culture. These pathogens included: methicillin-sensitive Staphylococcus aureus(MSSA), Bacillus cereus, and Mycobacterium Tuberculosis (MTB). In addition, 13 patients had negative CSF cultures but tested positive on CSF mPCR. These pathogens included Streptococcus pneumoniae (seven patients), Haemophilus influenzae (three patients), Streptococcus agalactiae (two patients), and Escherichia coli (one patient). All discordant results were confirmed by reviewing the patient's clinical presentation, CSF analysis, clinical course, and final diagnosis. Conclusion CSF mPCR panel is a highly sensitive and specific diagnostic tool for the diagnosis of CNS infections among all age groups in the UAE. Routine use of CSF mPCR panels can decrease healthcare costs by reducing the length of stay and can also aid antibiotic stewardship efforts by reducing antibiotic overuse in patients with viral CSF infections. CSF culture and mPCR complement each other by identifying CNS pathogens in patients with prior antibiotic exposure who would otherwise be missed if relying on CSF culture alone. However, concomitant CSF culture samples should be sent to avoid missing unusual CNS pathogens.

ADVANCING THE UNDERSTANDING OF CLINICAL SEPSIS USING GENE EXPRESSION-DRIVEN MACHINE LEARNING TO IMPROVE PATIENT OUTCOMES.

ABSTRACT: Sepsis remains a major challenge that necessitates improved approaches to enhance patient outcomes. This study explored the potential of machine learning (ML) techniques to bridge the gap between clinical data and gene expression information to better predict and understand sepsis. We discuss the application of ML algorithms, including neural networks, deep learning, and ensemble methods, to address key evidence gaps and overcome the challenges in sepsis research. The lack of a clear definition of sepsis is highlighted as a major hurdle, but ML models offer a workaround by focusing on endpoint prediction. We emphasize the significance of gene transcript information and its use in ML models to provide insights into sepsis pathophysiology and biomarker identification. Temporal analysis and integration of gene expression data further enhance the accuracy and predictive capabilities of ML models for sepsis. Although challenges such as interpretability and bias exist, ML research offers exciting prospects for addressing critical clinical problems, improving sepsis management, and advancing precision medicine approaches. Collaborative efforts between clinicians and data scientists are essential for the successful implementation and translation of ML models into clinical practice. Machine learning has the potential to revolutionize our understanding of sepsis and significantly improve patient outcomes. Further research and collaboration between clinicians and data scientists are needed to fully understand the potential of ML in sepsis management.

Seasonal Prevalence of Respiratory Pathogens Among Children in the United Arab Emirates: A Multicenter Cross-Sectional Study in the Pre-COVID-19 Era.

Background Viral respiratory infections in children pose a significant burden on healthcare facilities globally. In the United Arab Emirates (UAE) these account for 15% of all healthcare encounters among children. However, the seasonal prevalence and molecular epidemiology of respiratory viral infections in the UAE remains unknown. We sought to determine trends in seasonal viral prevalence in order to monitor disease activity and optimize the timing of Respiratory Syncytial Virus (RSV) prophylaxis among high-risk infants in the UAE. Methods This cross-sectional multicenter study included children 0-18 years of age who presented to a large private healthcare group in Dubai, UAE, and had upper respiratory samples collected for multiplex polymerase chain reaction (mPCR) testing between January 1st and December 31st, 2019. Sociodemographic, clinical, and molecular data were examined for children who tested positive for any pathogen on the mPCR panel. Results A total of three thousand and ninety-eight infants and children had mPCR assays performed during the study period, of which 2427 (78.3%) were positive for any respiratory pathogen. The median age of our sample population was 39 months and 56.8% were male. Emergency room was the most common site (34.7%) of sample collection and the vast majority of children presented with fever (85.3%). Rhinovirus/enterovirus was the most prevalent viral infection (45%) throughout the year and peaked in September, followed by Influenza (20.2%), and RSV (17.1%). RSV season, defined as an infection prevalence of >10%, occurred from August to December with a peak in October. Adenovirus (15.6%) infections peaked in June and accounted for 43% of hospitalizations in our study (p<0.05). Viral co-infections with RSV and rhinovirus/enterovirus were most common and observed in 19.9 % of children. Conclusion Rhinovirus/enterovirus is the most prevalent viral pathogen throughout the calendar year among the pediatric population in the UAE. RSV season begins earlier than reported in other countries regionally, hence RSV prophylaxis should be initiated in August to optimize protection among high-risk infants.

A TRANSCRIPTOMIC APPRECIATION OF CHILDHOOD MENINGOCOCCAL AND POLYMICROBIAL SEPSIS FROM A PRO-INFLAMMATORY AND TRAJECTORIAL PERSPECTIVE, A ROLE FOR VASCULAR ENDOTHELIAL GROWTH FACTOR A AND B MODULATION?

ABSTRACT: This study investigated the temporal dynamics of childhood sepsis by analyzing gene expression changes associated with proinflammatory processes. Five datasets, including four meningococcal sepsis shock (MSS) datasets (two temporal and two longitudinal) and one polymicrobial sepsis dataset, were selected to track temporal changes in gene expression. Hierarchical clustering revealed three temporal phases: early, intermediate, and late, providing a framework for understanding sepsis progression. Principal component analysis supported the identification of gene expression trajectories. Differential gene analysis highlighted consistent upregulation of vascular endothelial growth factor A (VEGF-A) and nuclear factor κB1 (NFKB1), genes involved in inflammation, across the sepsis datasets. NFKB1 gene expression also showed temporal changes in the MSS datasets. In the postmortem dataset comparing MSS cases to controls, VEGF-A was upregulated and VEGF-B downregulated. Renal tissue exhibited higher VEGF-A expression compared with other tissues. Similar VEGF-A upregulation and VEGF-B downregulation patterns were observed in the cross-sectional MSS datasets and the polymicrobial sepsis dataset. Hexagonal plots confirmed VEGF-R (VEGF receptor)-VEGF-R2 signaling pathway enrichment in the MSS cross-sectional studies. The polymicrobial sepsis dataset also showed enrichment of the VEGF pathway in septic shock day 3 and sepsis day 3 samples compared with controls. These findings provide unique insights into the dynamic nature of sepsis from a transcriptomic perspective and suggest potential implications for biomarker development. Future research should focus on larger-scale temporal transcriptomic studies with appropriate control groups and validate the identified gene combination as a potential biomarker panel for sepsis.

Pulmonary Artery Pseudoaneurysm: A Post-Covid Complication.

We present a case report of a potentially lethal post-COVID complication. A 65-year-old male presented with shortness of breath and fever with chills. He had recently recovered from COVID pneumonia. Contrast enhanced CT scan chest gave the suspicion of pulmonary pseudoaneurysm. CT aortogram revealed a well-defined rounded mass in the right lung mainly occupying the lower lobe of the right lung. Angiography through the right common femoral vein was performed and it confirmed a huge pseudoaneurysm arising from the posteromedial branch of the right descending interlobar artery. As the artery was not found suitable for endovascular embolization, the patient was referred to a thoracic surgeon.

A Rare Case of Primary Mycobacterium tuberculosis Myositis of the Thigh in an Immunocompetent Infant.

Mycobacterium tuberculosis (MTB) infection is a serious health condition that affects individuals of all age groups. Although MTB infections are more common in immunocompromised patients, they are frequently diagnosed in healthy individuals without apparent risk factors. Extrapulmonary infection is an uncommon manifestation of MTB infection, especially infection of the musculoskeletal system. Here, we present a rare case of a five-month-old immunocompetent infant who presented with a progressively enlarging swelling of the thigh without any other symptoms. After further evaluation, a diagnosis of primary MTB myositis of the thigh was made, which was treated successfully with first-line anti-tuberculosis therapy for nine months. This case report highlights the need to consider MTB infection in infants and children with unusual clinical findings. Due to its nonspecific symptoms and difficulty in diagnosis, clinicians need to maintain a high index of clinical suspicion for MTB infection, even in infants without risk factors for exposure.

Clinical Characteristics of Children With COVID-19 in the United Arab Emirates: Cross-sectional Multicenter Study.

BACKGROUND: COVID-19 has infected over 123 million people globally. The first confirmed case in the United Arab Emirates (UAE) was reported on January 29, 2020. According to studies conducted in the early epicenters of the pandemic, COVID-19 has fared mildly in the pediatric population. To date, there is a lack of published data about COVID-19 infection among children in the Arabian region. OBJECTIVE: This study aims to investigate the clinical characteristics, laboratory findings, treatment, and outcomes of children with COVID-19. METHODS: This cross-sectional, multicenter study included children with confirmed COVID-19 infection admitted to 3 large hospitals in Dubai, UAE, between March 1 and June 15, 2020. Serial COVID-19 polymerase chain reaction (PCR) testing data were collected, and patients' demographics, premorbid clinical characteristics, and inpatient hospital courses were examined. RESULTS: In all, 111 children were included in our study and represented 22 nationalities. Of these, 59 (53.2%) were boys. The mean age of the participants was 7 (SD 5.3) years. About 15.3% of children were younger than 1 year. Only 4 (3.6%) of them had pre-existing asthma, all of whom had uneventful courses. At presentation, of the 111 children, 43 (38.7%) were asymptomatic, 68 (61.2%) had mild or moderate symptoms, and none (0%) had severe illness requiring intensive care. Fever (23/111, 20.7%), cough (22/111, 19.8%), and rhinorrhea (17/111, 15.3%) were the most common presenting symptoms, and most reported symptoms resolved by day 5 of hospitalization. Most patients had no abnormality on chest x-ray. The most common laboratory abnormalities on admission included variations in neutrophil count (22/111, 24.7%), aspartate transaminase (18/111, 22.5%), alkaline phosphatase (29/111, 36.7%), and lactate dehydrogenase (31/111, 42.5%). Children were infrequently prescribed targeted medications, with only 4 (3.6%) receiving antibiotics. None of the 52 patients tested for viral coinfections were positive. COVID-19 PCR testing turned negative at a median of 10 days (IQR: 6-14) after the first positive test. Overall, there was no significant difference of time to negative PCR results between symptomatic and asymptomatic children. CONCLUSIONS: This study of COVID-19 presentations and characteristics presents a first look into the burden of COVID-19 infection in the pediatric population in the UAE. We conclude that a large percentage of children experienced no symptoms and that severe COVID-19 disease is uncommon in the UAE. Various laboratory abnormalities were observed despite clinical stability. Ongoing surveillance, contact tracing, and public health measures will be important to contain future outbreaks.

Retraction: Nutritional and Biochemical Parameters Among Multiple Sclerosis Patients: A Case-Control Study.

[This retracts the article DOI: 10.7759/cureus.15108.].

Nutritional and Biochemical Parameters Among Multiple Sclerosis Patients: A Case-Control Study.

Background The pathogenesis and prognosis of multiple sclerosis (MS) is an area of active medical research. Dietary and biochemical parameters such as serum 25-dihydroxycholecalciferol, magnesium, and potassium play a role in disease progression. This study aimed to compare the nutritional status and biochemical profile of patients with and without MS. Methodology This case-control study included a total of 112 participants (56 in the control group and 56 in the MS group). The participants' socioeconomic and demographic profiles, nutritional status, and biochemical details were all gathered using history, patient files, and records. The effect of these parameters on the presence of MS was evaluated using a decision tree model. Student's t-test and Mann-Whitney U test were performed to compare these parameters. Results A decision tree model was developed with an accuracy rate of 86.52%. The vitamin and mineral intake of the groups showed significant statistical differences (p = 0.001). The differences were important in terms of biochemical parameters, especially serum levels of 25-dihydroxycholecalciferol and potassium. Conclusions The key parameters that varied between MS patients and the control group, according to the constructed decision tree, were serum levels of 25-dihydroxycholecalciferol, magnesium, calcium, potassium, and carbohydrate intake. Nutritional measures against MS can be taken based on the decision tree.

High diagnostic accuracy of automated rapid Strep A test reduces antibiotic prescriptions for children in the United Arab Emirates.

BACKGROUND: Diagnosis of Group A Streptococcus (GAS) pharyngitis in children is hindered by variable sensitivity of clinical criteria and rapid Strep A tests (SAT), resulting in reliance on throat cultures as the gold standard for diagnosis. Delays while awaiting culture reports result in unnecessary antibiotic prescriptions among children, contributing to the spread of antimicrobial resistance (AMR). METHODS: Diagnostic accuracy study of an automated SAT (A-SAT) in children up to 16 years of age presenting to an emergency room with signs and symptoms of pharyngitis between March and June 2019. Paired throat swabs for A-SAT and culture were collected. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for A-SAT were calculated. RESULTS: Two hundred and ninety-one children were included in this study. 168 (57.7%) were boys and the mean age was 4.2 years. A-SAT was positive in 94 (32.3%) and throat culture was positive in 90 (30.9%) children. A-SAT and throat culture results showed a high level of consistency in our cohort. Only 6 (2%) children had inconsistent results, demonstrating that the A-SAT has a high sensitivity (98.9%), specificity (97.5%), PPV (94.7%) and NPV (99.5%) for the diagnosis of GAS pharyngitis in children. Only 92 (32%) children were prescribed antibiotics while the vast majority (68%) were not. CONCLUSIONS: A-SAT is a quick and reliable test with diagnostic accuracy comparable to throat culture. Its widespread clinical use can help limit antibiotic prescriptions to children presenting with pharyngitis, thus limiting the spread of AMR.

HRCT Features Of COVID-19 In Relation To Duration Of Disease.

BACKGROUND: Despite the fact that much has been written on various aspects of COVID-19, literature lacks a detailed and accurate description of HRCT findings in relation to the duration of the disease. The aim of this study was to investigate the difference in HRCT scan findings depending on the time after onset of the disease. The objective of the study is to identify and compare findings of HRCT scan at different time points after onset of the disease. METHODS: A total of 224 patients, scanned over a period of 2 months, were placed in one of the four groups at the time of their scan depending on the days lapsed after their symptoms appeared. All scans were carried out on the same machine. Findings in each group were recorded and compared. A finding showing significant difference between groups indicates its importance in describing the course of the disease. Analysis was done on SPSS 23. RESULTS: Ground glass opacities in posterior segments of one or more lobes was the most common feature and had a significant association with first 5 days of the disease (p=.027). Interlobular thickening and subpleural reticulation, are found between 3-5 days or later in the course of the disease (p=.000). CONCLUSION: Ground glass opacities located in posterior segments are the predominant feature in patients who are scanned up to 5 days after their symptoms appear. This feature is the most common in scans done in asymptomatic cases too. Interlobular septal thickening and subpleural reticulation start appearing at 3 days of disease process.

Revisiting Drug Development Against the Neglected Tropical Disease, Amebiasis.

Amebiasis is a neglected tropical disease which is caused by the protozoan parasite Entamoeba histolytica. This disease is one of the leading causes of diarrhea globally, affecting largely impoverished residents in developing countries. Amebiasis also remains one of the top causes of gastrointestinal diseases in returning international travellers. Despite having many side effects, metronidazole remains the drug of choice as an amebicidal tissue-active agent. However, emergence of metronidazole resistance in pathogens having similar anaerobic metabolism and also in laboratory strains of E. histolytica has necessitated the identification and development of new drug targets and therapeutic strategies against the parasite. Recent research in the field of amebiasis has led to a better understanding of the parasite's metabolic and cellular pathways and hence has been useful in identifying new drug targets. On the other hand, new molecules effective against amebiasis have been mined by modifying available compounds, thereby increasing their potency and efficacy and also by repurposing existing approved drugs. This review aims at compiling and examining up to date information on promising drug targets and drug molecules for the treatment of amebiasis.

A rare case of orbital myositis.

The orbital myositis is a rare inflammatory disorder of extraocular muscles and is considered a subtype of nonspecific orbital inflammatory syndrome. It is usually a unilateral disease process with a limited course. We report a case of a 34-year-old man who was referred to the Radiology Department at Shifa International Hospital, Islamabad with 6 months history of severe pain, swelling, and redness in the left eye associated with blurring of vision and headache. Initially, the patient had contrast enhanced CT scan orbits which showed asymmetrically thickened, minimally enhancing left optic nerve having indistinct margins with thickened superior rectus and superior oblique muscles, indistinct superior ophthalmic vein, soft tissue nodularity in the medial intraconal space fat, and slight left exophthalmos. Differentials of orbital pseudo tumour and lymphoma were given. Further evaluation by post contrast MRI with orbits protocol was suggested which showed proptosis, the significant infiltrative disease in the superomedial aspect of left orbit involving the adjacent fat with thickening, enlargement, and heterogeneous enhancement of the superior rectus, medial rectus, and superior oblique muscles with relatively lesser degree involvement of their tendons. The infiltrative thickening also involved the optic nerve sheath and seen invading the optic nerve at the orbital apex. On basis of the imaging features and clinical picture, a diagnosis of orbital myositis with optic neuropathy was given. The patient was given corticosteroids and showed rapid symptomatic improvement.

Diagnostic accuracy of QuickVue® Dipstick Strep A test and its effect on antibiotic prescribing in children in the United Arab Emirates.

BACKGROUND: Unnecessary antibiotic prescription to patients with upper respiratory tract infections (URTIs) has led to the increase in antibiotics resistant bacteria rates. In this study, we evaluated the diagnostic accuracy of QuickVue® Dipstick Strep A test (QV-SAT) in children presenting with acute pharyngotonsillitis and its effect on antibiotic prescribing. METHODS: A single-gated diagnostic accuracy study of children with fever, runny nose, and tonsillitis presenting to a paediatric clinic between March 2016 and September 2018. Paired throat swabs for QV-SAT and culture were collected. None of the children received antibiotics prior to sample collection. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the test were calculated. RESULTS: Two hundred four children were included in this study. 111 (54.4%) were boys and 146 (71.6%) were under the age of 5 years. QV-SAT was positive in 44 (21.6%) and throat culture was positive for Group A ß- haemolytic Streptococcus (GAS) in 42 (20.6%) of the children. The results of QV-SAT were highly consistent with culture results: only 2 (0.9%) children with negative results had a positive throat culture. The sensitivity of the QV-SAT in the identification of GAS infection was 100% (95% CI 91.6%, 100%) and the NPV was 100% (95% CI 99.9%, 100%). Only 42 children ( 20.6%) were given antibiotics, while 162 (79.4%) were not. CONCLUSION: The QV-SAT is a quick and reliable test that can help dramatically reduce antibiotic prescriptions to children presenting with fever and acute pharyngotonsillitis.

Resilience as a translational endpoint in the treatment of PTSD.

Resilience is a neurobiological entity that shapes an individual's response to trauma. Resilience has been implicated as the principal mediator in the development of mental illness following exposure to trauma. Although animal models have traditionally defined resilience as molecular and behavioral changes in stress responsive circuits following trauma, this concept needs to be further clarified for both research and clinical use. Here, we analyze the construct of resilience from a translational perspective and review optimal measurement methods and models. We also seek to distinguish between resilience, stress vulnerability, and posttraumatic growth. We propose that resilience can be quantified as a multifactorial determinant of physiological parameters, epigenetic modulators, and neurobiological candidate markers. This multifactorial definition can determine PTSD risk before and after trauma exposure. From this perspective, we propose the use of an 'R Factor' analogous to Spearman's g factor for intelligence to denote these multifactorial determinants. In addition, we also propose a novel concept called 'resilience reserve', analogous to Stern's cognitive reserve, to summarize the sum total of physiological processes that protect and compensate for the effect of trauma. We propose the development and application of challenge tasks to measure 'resilience reserve' and guide the assessment and monitoring of 'R Factor' as a biomarker for PTSD.

Hypothalamic Response to Kisspeptin-54 and Pituitary Response to Gonadotropin-Releasing Hormone Are Preserved in Healthy Older Men.

BACKGROUND: Male testosterone levels decline by 1% per year from the age of 40 years. Whilst a primary testicular deficit occurs, hypothalamic or pituitary dysregulation may also coexist. This study aimed to compare the hypothalamic response to kisspeptin-54 and the pituitary response to gonadotropin-releasing hormone (GnRH) of older men with those of young men. METHODS: Following 1 h of baseline sampling, healthy older men (n = 5, mean age 59.3 ± 2.9 years) received a 3-h intravenous infusion of either vehicle, kisspeptin-54 0.1, 0.3, or 1.0 nmol/kg/h or GnRH 0.1 nmol/kg/h, on five different study days. Serum gonadotropins and total testosterone were measured every 10 min and compared to those of young men (n = 5/group) (mean age 28.9 ± 2.0 years) with a similar body mass index (24 kg/m2) who underwent the same protocol. RESULTS: Kisspeptin-54 and GnRH significantly stimulated serum gonadotropin release in older men compared to vehicle (p < 0.001 for all groups). Gonadotropin response to kisspeptin-54 was at least preserved in older men when compared to young men. At the highest dose of kisspeptin-54 (1.0 nmol/kg/h), a significantly greater luteinising hormone (LH) (p = 0.003) response was observed in older men. The follicle-stimulating hormone (FSH) response to GnRH was increased in older men (p = 0.002), but the LH response was similar (p = 0.38). Serum testosterone rises following all doses of kisspeptin-54 (p ≤ 0.009) were reduced in older men. CONCLUSIONS: Our data suggest that healthy older men without late-onset hypo-gonadism (LOH) have preserved hypothalamic response to kisspeptin-54 and pituitary response to GnRH, but impaired testicular response. Further work is required to investigate the use of kisspeptin-54 to identify hypothalamic deficits in men with LOH.

The identification of elevated urinary kisspeptin-immunoreactivity during pregnancy.

BACKGROUND: Kisspeptin is an arginine-phenylalanine amide peptide hormone critical for reproductive function. Kisspeptin is also abundantly expressed in the placenta, where it has an important physiological role in regulating placental invasion. Accordingly, plasma kisspeptin concentrations rise dramatically during normal pregnancy. However, lower plasma concentrations of kisspeptin are associated with obstetric complications such as pre-eclampsia. It is not currently known whether kisspeptin-immunoreactivity (IR) can be detected in bodily fluids not requiring invasive collection such as saliva or urine. AIM: To determine the clinical utility of urinary and salivary kisspeptin measurement in healthy pregnant women. METHODS: Forty-nine healthy third trimester pregnant women (gestational age 34 ± 0.6 w) from a single maternity unit and 50 healthy non-pregnant women were recruited. Urine, saliva and blood were simultaneously collected from all volunteers. Kisspeptin concentrations were determined by in-house manual radioimmunoassay. RESULTS: Mean concentrations of plasma kisspeptin-IR were over 200-fold greater in third trimester pregnant women compared with non-pregnant women (13,783 ± 864 pmol/L, pregnant; 65 ± 13 pmol/L, non-pregnant; p < 0.0001). The urine kisspeptin:creatinine ratio was greater in pregnant women when compared with non-pregnant women (urine kisspeptin:creatinine: 37 ± 6 pmol/µmol, pregnant; 7 ± 1 pmol/µmol, non-pregnant; p < 0.0001). Mean concentrations of salivary kisspeptin-IR were not statistically different between pregnant and non-pregnant women (123 ± 34 pmol/L, pregnant; 83 ± 33 pmol/L, non-pregnant; p = 0.2). CONCLUSION: We demonstrate for the first time that kisspeptin-IR is elevated in urine during pregnancy. Urinary measurement of kisspeptin-IR may, therefore, offer a non-invasive and simple method of screening for pregnancy and obstetric complications.

Persistent antibodies to HPV virus-like particles following natural infection are protective against subsequent cervicovaginal infection with related and unrelated HPV.

Whether persistent human papillomavirus (HPV) IgG antibodies following natural infection are protective against subsequent infection is unknown. In a cohort of 508 college women followed for 3 y, persistent seropositivity was defined as the presence of type-specific HPV virus-like particle (VLP) antibodies at > or = 2 consecutive visits 1 y apart. Protection from incident infection with any HPV was conferred by persistent antibodies to HPV16 (p = 0.02), HPV31 (p < 0.001), HPV33 (p = 0.03), HPV35 (p = 0.002), HPV52 (p = 0.007), HPV45 (p = 0.003), and HPV53 (p = 0.01). The risk of incident infection with species-specific HPV types was also decreased in women with persistent antibodies to any HPV type in that group, suggesting that exposure to HPV with persistent development of antibody response can be protective, and may explain the decreased efficacy of HPV vaccine in women with prior exposure.