Prevalence of Acute Tonsillitis and Its Association With Oral Hygiene Among the Population of Taif City, Saudi Arabia

Introduction  Dental surfaces have dense bacterial deposits, and poor oral hygiene can exacerbate bacterial infections, causing acute tonsillitis. The study aims to quantify acute tonsillitis prevalence and assess its association with oral hygiene practices. Methods  A descriptive cross-sectional study aimed to assess the prevalence of acute tonsillitis and its association with oral hygiene was conducted among adults aged 20 and above in Taif City, Saudi Arabia. Illiterates and those unwilling to participate were excluded. We employed an Arabic online self-administered questionnaire that was disseminated conveniently via Google Forms to social media assessing oral hygiene such as last dental visit, age at starting dental care, number of toothbrushes per day, frequency of toothbrush change, and duration of brushing teeth, and acute tonsillitis characteristics of the participants. Results About 393 participated in the study. Of them, 54% were aged 20-30, 53% were males, and 70% had a university education. The prevalence of acute tonsillitis was 64%. Approximately 28% reported dental clinic visits within three months, and 21% initiated oral hygiene practices at age 20. Among participants, 43% brushed twice daily, with 33% spending one minute and 43% two minutes. About 31% replaced toothbrushes every three months, while 23% acknowledged having bad breath. Experiencing bad breath, changing toothbrushes every three months, and having dental visits within less than three months were associated with having acute tonsillitis (p<0.05). However, regression analysis revealed that experiencing bad breath (OR: 2.11, 95% CI: 1.23, 3.70) was associated with a higher risk of acute tonsillitis, while less frequent toothbrush changes correlated with a lower risk (OR: 0.54, 95% CI: 0.30, 0.94). Conclusion  This study revealed a substantial prevalence of acute tonsillitis among adults in Taif City. Oral care practices need improvement. There are significant associations between oral hygiene practices, bad breath, and the occurrence of acute tonsillitis. Addressing oral hygiene practices could be a key focus for preventative measures.

Evaluating the Knowledge, Attitudes, and Practices of Saudi Arabian Parents Regarding Red Flags in Developmental Milestones

Background Parents serve a fundamental role in monitoring developmental milestones and identifying potential delays during early childhood, enabling timely interventions. However, previous studies in Saudi Arabia have shown limited awareness among parents regarding age-specific norms and red flags across developmental domains. This knowledge gap can severely impact the detection and management of abnormalities. Hence, a comprehensive understanding of Saudi parental knowledge, attitudes, and practices concerning childhood developmental trajectories is imperative.  Methodology This cross-sectional study assessed developmental milestone awareness, beliefs, and behaviors among Saudi parents. A sample of 1,052 parents completed a validated 38-item questionnaire covering knowledge, attitudes, practices, and demographics. Knowledge was assessed across developmental domains using 22 multiple-choice questions, with scores categorized as excellent (≥75%), good (50%-75%), fair (40%-50%), or poor (≤39%). Attitudes and practices were captured on five-point Likert scales. Descriptive and chi-square analyses were conducted using IBM SPSS Statistics for Windows, Version 28.0 (IBM Corp., Armonk, NY).  Results The majority of participants were females (844, 80.2%), with a mean age of 38.8 years. Serious knowledge inadequacies existed regarding developmental timelines across domains, especially motor milestones like crawling (93, 29.4% correct), sitting unsupported (45, 27.6%), pointing at objects (278, 26.4%), and responding to names (440, 41.8%). Overall, 2 (0.2%) participants showed excellent and 281 (26.7%) showed good understanding, while 490 (46.6%) had poor knowledge. Significant sociodemographic variations were observed, with women and experienced parents demonstrating greater awareness (P < 0.001). Despite knowledge gaps, 542 (51.5%) actively sought developmental information themselves, and over 50% trusted pediatric guidance. Most participants expressed a willingness to undergo screenings if risk factors existed and reported spending a considerable amount of daily interaction time with their children, focusing on developmental needs. Conclusions Critical developmental milestone knowledge shortfalls and selective attitudes persist among Saudi parents, warranting public education and physician-parent communication that enhance interventions to enable impactful developmental monitoring and prompt responses to abnormalities in a timely manner.

Knowledge, Awareness, and Attitude Regarding Obstructive Sleep Apnea Among Primary Healthcare Physicians in the Al-Baha Region of Saudi Arabia

INTRODUCTION

Obstructive sleep apnea (OSA) is a clinically significant disorder that requires attention from healthcare professionals. This study aimed to assess the knowledge, awareness, and attitude of primary healthcare physicians regarding OSA in Saudi Arabia.

METHODOLOGY

A cross-sectional observational study design was employed from January 18, 2023, to August 18, 2023, focusing on primary healthcare physicians practicing in the Al-Baha region of Saudi Arabia. The survey included questions related to knowledge, awareness, and attitudes toward OSA, using the Obstructive Sleep Apnea Knowledge and Attitude (OSAKA) questionnaire for OSA, and demographic information. Descriptive statistics and chi-square tests were used to analyze the data.

RESULTS

A total sample size of 174 primary health care physicians was collected, where the majority of participants were male (101, 58.0%), and the mean age of the participants was 32.73 years (SD = 9.14). The item with the most correct answers was "The majority of patients with obstructive sleep apnea snore" (150, 86.2%). On the other hand, the item with the lowest number of correct answers was "Laser-assisted uvulopalatoplasty is an appropriate treatment for severe obstructive sleep apnea" (17, 9.8%). The majority of participants agreed that it is essential for physicians to know about OSA as a clinical disorder (161, 92.5%). However, when it came to screening all patients for possible OSA, there was a higher proportion of participants who disagreed or strongly disagreed (111, 63.8%). In general, the majority of participants had a low level of knowledge (109, 62.6%). Gender was significantly associated with both knowledge (p = 0.021) and awareness (p = 0.039), as well as nationality (knowledge (p = 0.012) and awareness (p = 0.039)), and specialty training, which was significantly associated with both knowledge (p = 0.000) and awareness (p = 0.002).

CONCLUSION

Although all participants acknowledged that OSA is a clinical disease, their perspectives on screening and levels of confidence in utilizing screening techniques varied. While the participants exhibited commendable understanding in the majority of domains, there were some facets of OSA in which they lacked expertise.

Retraction: Emphysematous Cystitis: A Radiological Diagnosis of Potentially Life-Threatening Infection

[This retracts the article DOI: 10.7759/cureus.20201.].

Self-Medication Practices Among the General Population in Al-Baha City, Saudi Arabia: A Cross-Sectional Study

Background The practice of self-medication (SM) is the use of self-consuming medication without consulting healthcare which carries its own risks. SM patterns differ across populations and are influenced by several factors. This study aimed to assess the prevalence of SM practices in Al-Baha, Saudi Arabia, to identify the factors contributing to this practice and develop effective strategies to decrease its occurrence and associated risks. Methodology This cross-sectional study was conducted in Al Baha Province, Saudi Arabia, over two weeks in July 2023, with a sample of 580 participants. Eligible participants were males and females, both Saudi and non-Saudi, aged 18-65. The data were collected using a self-administered online questionnaire. Results Of all participants, 48.7% admitted taking medications without a healthcare practitioner's prescription in the last three months. Analgesics were the most common SM (29.1%), followed by vitamins and minerals (16.2%), and antipyretics (14.1%). The side effects experienced from SM included nausea (24.5%), headache (20.5%), and shortness of breath (8.7%). Regarding the source of medication, the majority (61.9%) obtained medications from a pharmacy and 14.6% used existing stock. Age was significantly associated with higher rates in the 18-29 and 40-49 age groups. Educational status was significantly associated with higher SM among graduates. Regarding reading medical instructions, 39.2% always read, 47.7% sometimes read, and 13.1% never read. Regarding antibiotic SM, 61 participants reported using over-the-counter (OTC) antibiotics. Common reasons for use included sore throat (27.8%) and common cold (19.6%). The most common reason for SM was to save time (25.9%), followed by avoiding crowds and long waits (17.1%). Conclusions A significant prevalence of SM practice concerning antibiotic misuse and sex differences with female dominance was detected. We recommend further public awareness activities from related organizations and more regulations for OTC prescription practices to ensure safe SM practices. In addition, further research is needed to explore SM patterns.

Prevalence of Shoulder and Neck Pain Among Healthcare Workers in the Central Region of Saudi Arabia

Introduction Musculoskeletal disorders (MSDs) have a tremendous impact on working people and are becoming a serious problem in the modern society. The healthcare system is regarded as having one of the most physically demanding jobs, and the risk of musculoskeletal injuries is high. Irrespective of their age, healthcare workers (HCWs) worldwide frequently experience shoulder and neck pain. In our study, we sought to understand what initiates shoulder and neck pain, such as stress or environmental factors, and what causes shoulder and neck discomfort among Saudi Arabian healthcare professionals. Methods A descriptive, cross-sectional study was conducted from 2022 to 2023, assessing shoulder and neck pain among healthcare workers in the central region of Saudi Arabia. An online survey was used, with 409 participants aged 20 or older. The questionnaire included socio-demographic data, Shoulder Pain and Disability Index (SPADI) questionnaire to measure shoulder pain and disability, neck Bournemouth questionnaire (NBQ) to assess neck pain, and quadruple visual analogue scale (QVAS) to measure the intensity of pain. Results Of the 409 HCWs, 56% were males, and 56.5% belonged to the age group of 20-30 years. The prevalence of high-intensity pain based on QVAS criteria was 29.3%. The mean percentage of neck pain (32.3%) was slightly higher than shoulder pain (31.8%). There was a significant association between the level of pain intensity in terms of the total score of NBQ, SPADI score, and its dimensions. It is interesting to know that HCWs with associated chronic diseases had higher scores in all three questionnaires (NBQ, SPADI, and QVAS). Conclusion High-intensity musculoskeletal pain was relatively high among HCWs. It was found that neck pain affected HCWs more than shoulder pain. Furthermore, an increased pain intensity in the shoulder and neck was more frequently seen in HCWs with chronic diseases. More studies are needed to determine the causes and risk factors for neck and shoulder pain to help improve the healthcare system and patient care.

Assessment of the Current Knowledge and Practice of General Practitioners Towards Laryngopharyngeal Reflux in Saudi Arabia

Background General practitioners (GPs) have a significant role in the diagnosis of patients with laryngopharyngeal reflux (LPR). Some published data revealed a lack of knowledge among GPs about the disease, consequently, this lack of knowledge impacted their performance. This survey aims to assess the current knowledge and practice of general practitioners regarding laryngopharyngeal reflux in Saudi Arabia. Methodology This survey study was conducted to assess the current knowledge and practice of general practitioners regarding laryngopharyngeal reflux in Saudi Arabia using an online questionnaire. The questionnaire was distributed and collected from the five regions in Saudi Arabia, which are The Central Region (Riyadh, Qassim), Eastern Region (Dammam, Al-Kharj, Al-Ahasa), Western Region (Makkah, Madinah, Jeddah), Southern Region (Asir, Najran, Jizan), and Northern Region (Tabuk, Jouf, Hail). Results In the current study, we collected data from 387 general practitioners, 61.8% of whom were aged between 21-30 years old, and 57.4% of the participants were males. Moreover, 40.6% of the participants thought that both LPR and gastroesophageal reflux disease (GERD) share pathophysiology, however, they are two different diseases considering their clinical presentation. Moreover, it was found that heartburn was the most known symptom of LPR among the participants (Mean score 2.14 (SD=1.31), where a lower score indicated more relation). Considering the treatment of LPR, 40.6% and 40.3% of the participants reported using proton pump inhibitors once or twice daily respectively. In contrast, antihistamine/H2 blockers, alginate, and magaldrate were used to a lesser extent as reported by 27.1%, 21.7%, and 12.1%. Conclusion The current study showed limited knowledge among general practitioners considering LPR with a higher rate of referring patients to other departments depending on symptoms which may increase the pressure on other departments of mild cases.

Melatonin attenuates thioacetamide-induced liver fibrosis in male rats through modulation of interleukin-6, interleukin-4, apoptosis and urokinase plasminogen activator receptor-associated protein/Endo180

Liver fibrosis is a chronic progressive disease, its resolution still unclear, and the current study explored the role of melatonin in modulation of interleukin-6 (IL-6), interleukin-4 (IL-4), transforming growth factor beta1 (TGF-β1) and urokinase plasminogen activator receptor-associated protein/Endo180 (uPARAP/Endo180) pathway in thioacetamide (TAA)-induced hepatotoxicity. Thirty two adult Sprague-Dawley rats were divided into four groups: vehicle control group, TAA-induced liver fibrosis group that was left untreated, melatonin administration before and along with TAA and melatonin along with TAA group. TTA-induced massive liver necrosis, fibrosis around portal tract and increases serum levels of liver enzymes and total bilirubin when compared with control vehicle group. While both melatonin pretreatment and treatment retained liver parenchyma and liver enzymes quite similar to control group and reduced TAA-induced liver injury. Notably, melatonin pretreatment and treatment increased collagen degradation in TAA liver injury by19, 31.7-fold respectively evidence by collagen percentage area. Melatonin also decreased the amount of thiobarbituric acid reactive compounds and retained the reduced glutathione and superoxide dismutase to basal level quite similar to control group. Additionally, melatonin significantly (P value ≤0.05) decreased the levels of TGF-β1, epidermal growth factor (EGF), hydroxyproline, tissues IL-6, caspase-3, and receptor interacting serine/threonine kinase1 (RIPK1), fibrillin-1, and - smooth muscle actin in the liver tissues while significantly (P value ≤0.05) increasing the levels of IL-4 and uPARAP/Endo180. Due to its anti-inflammatory, anti-apoptotic, and antioxidant capabilities as well as its ability to decrease hepatic stellate cell activation and fibrogenesis, these data imply that melatonin has a powerful anti-fibrotic effect.

Disease-specific quality of life in patients with diabetic neuropathy

OBJECTIVES

To compare health-related quality of life (HRQoL) among patients with diabetes mellitus (DM) and diabetic neuropathy (DN) (D+N) with patients with DM without DN (D-DN) and healthy participants. To evaluate factors associated with poor HRQoL in patients with DN.

METHODS

This study included 306 participants residing in Bisha, Saudi Arabia. Patients with DM were screened for DN using the Michigan Neuropathy Screening Instrument. Neuropathy severity, disability and HRQoL were determined using the Neuropathy Severity Scale (NSS), the Neuropathy Disability Score (NDS), and the Norfolk Quality of Life-Diabetic Neuropathy (QOL-DN) tool, respectively. Nerve conduction studies (NCSs) were also performed.

RESULTS

The D+DN group had poorer overall and domain HRQoL scores compared to the D-DN group (p<0.001). There was a strong correlation between overall HRQoL score and both NDS and NSS scores in the D+DN group (ρ= -0.71 and p<0.0001; ρ= -0.81 and p<0.0001, respectively). There was also a significant difference in all mean HRQoL domain scores between D+DN participants with normal and abnormal NCS. Physical inactivity (p=0.043), duration of DM (p<0.0001), abnormal NCS, NSS (p<0.0001), and NDS (p<0.0001) predicted HRQoL in the D+DN group.

CONCLUSION

D+DN participants had a worse HRQoL compared with D-DN and healthy counterparts. NDS, NNS, physical inactivity, abnormal NCS, and duration of DM independently predicted poor HRQoL in D+DN participants.

Emphysematous Cystitis: A Radiological Diagnosis of Potentially Life-Threatening Infection

Urinary tract infections are very prevalent among women. The majority of urinary tract infections are uncomplicated and can be managed empirically with no further investigations. However, imaging studies may be indicated in patients with severe or persistent symptoms. Complicated urinary tract infections typically develop in the setting of diabetes mellitus. We report a case of a 52-year-old woman who presented to the emergency department with severe lower abdominal pain for two days that was associated with nausea, vomiting, and fever. There was no history of change in urine or bowel habits. Besides the history of well-controlled asthma, the patient was not known to have any comorbid medical condition. Upon examination, the patient had tachycardia, low-grade fever, and a localized suprapubic tenderness with guarding. Laboratory investigation revealed leukocytosis, elevated erythrocyte sedimentation rate and C-reactive protein, and deranged renal functions. Further, urinalysis revealed numerous white blood cells, red blood cells, positive nitrite, and leukocyte esterase. A computed tomography scan demonstrated the presence of small locules of gas within the lumen and the wall of the bladder representing emphysematous cystitis. The patient was admitted to the intensive care unit. She received aggressive hydration therapy and a short course of opioid therapy for pain control. Broad-spectrum antibiotic therapy in the form of piperacillin-tazobactam was initiated. Over the following few days, the patient exhibited significant improvement in his symptoms and resolution of the laboratory parameters. Emphysematous cystitis is a rare infection of the lower urinary tract with gas formation. The case highlighted that such a condition may develop in the absence of diabetes mellitus or other risk factors. Prompt treatment is crucial as emphysematous cystitis can be life-threatening if the diagnosis is missed or delayed.

Synchronous incidental double parathyroid adenomas and papillary thyroid carcinoma: A case report with literature review

The association between parathyroid and thyroid diseases is not uncommon; however, the concurrent presence of parathyroid adenoma and thyroid cancer is rare. Awareness of this situation will enable clinicians to consider possible parathyroid pathology in patients with papillary thyroid cancer. The presence of parathyroid adenoma leading to primary hyperparathyroidism and the coexistence of thyroid papillary cancer is rare. We report a case of a 55-year-old female with papillary cancer admitted for surgery. Preoperative laboratory findings revealed normal calcium level and normal intact parathyroid hormone (PTH) level. Thyroidectomy and excision of abnormal enlarged double parathyroid glands were performed. Histological examination revealed parathyroid adenoma. Serum calcium was within the normal range after surgery. We recommend a preoperative check of calcium in patients with thyroid cancer.

Interplay of Microbiota and Citrullination in the Immunopathogenesis of Rheumatoid Arthritis

Microbiota is a balanced ecosystem that has important functions to the host health including development, defense, digestion, and absorption of dietary fibers and minerals, vitamin synthesizes, protection, and training the host immune system. On the other hand, its dysbiosis is linked to many human diseases such as rheumatoid arthritis (RA). The RA is an inflammatory autoimmune disorder caused by genetic and environmental factors; microbiota may be considered as a risk environmental factor for it. Citrullination is a post-translation modification (PMT) that converts the amino acid arginine to amino acid citrulline in certain proteins. These citrullinated proteins are recognized as a foreign antigen by the immune system resulting in the upregulation of inflammatory action such as in RA. The current work highlights the effect of both gut and oral microbiota dysbiosis on the development of RA, as well as discusses how the alteration in microbiota composition leads to the overgrowth of some bacterial species that entangled in RA pathogenicity. The evidence suggested that some oral and gut microbial species such as Porphyromonas gingivalis and Prevotella copri, respectively, contribute to RA pathogenesis. During dysbiosis, these bacteria can mediate the citrullination of either human or bacteria proteins to trigger an immune response that leads to the generation of autoantibodies.

Aberrant right subclavian artery in a cadaver: a case report of an aortic arch anomaly

In early embryogenesis, aortic anomalies occur as a consequence of disorders in the development of the primitive aortic arches system. Aberrant right subclavian artery, also known as arteria lusoria, is one of the important congenital anomalies of the aortic arch, in which the right subclavian artery arises from the arch of aorta instead of the brachiocephalic trunk. During routine dissection of a female cadaver, we observed retro-oesophageal aberrant right subclavian artery arising as the fourth branch from the aortic arch. In this case, the brachiocephalic trunk was absent. Early detection of aortic arch anomalies through diagnostic interventions is helpful to avoid complications during surgical procedures.

Effect of sorafenib starting dose and dose intensity on survival in patients with hepatocellular carcinoma: Results from a Canadian Multicenter Database

Background

Sorafenib has been shown to improve survival in patients with advanced hepatocellular carcinoma (HCC), however, full dose can be difficult to tolerate. The aim of this study was to determine whether sorafenib starting dose and mean dose intensity affect survival.

Methods

Patients treated with sorafenib for HCC from January 2008 to July 2016 in several Canadian provinces were included and retrospectively analyzed. The primary end point was overall survival (OS) of patients starting on sorafenib full dose compared to reduced dose. Secondary analysis compared OS with different mean dose‐intensity groups. Survival outcomes were assessed with Kaplan‐Meier curves and Cox proportional hazards models. A propensity score analysis was performed to account for treatment bias and confounding.

Results

Of 681 patients included, sorafenib was started at full dose in 289 patients (42%). Median survival for starting full and reduced dose was 9.4 months and 8.9 months (P = .15) respectively. After propensity score matching and adjusting for potential confounders there was still no difference in survival (HR 0.8, 95% CI, 0.61‐1.06, P = .12). Almost half of the patients (45%) received a dose intensity < 50%. Median survival for mean dose intensity > 75%, 50%‐75%, and < 50% were 9.5 months, 12.9 months, and 7.1 months (P = .005) respectively. In multivariable models, starting dose(HR 1.16, 95% CI 0.93‐1.44, P = .180) and mean dose intensity were not associated with survival.

Conclusions

Starting HCC patients on a reduced dose of sorafenib compared to full dose may not compromise survival. Mean dose‐intensity of sorafenib may also not affect survival.

Incidental Extraspinal Findings in the Thoracic Spine during Magnetic Resonance Imaging of Intervertebral Discs

Objective:

The purpose of this research was to determine the frequency of incidental extraspinal findings in the thoracic spine on magnetic resonance imaging (MRI).

Materials and Methods:

A total of 120 thoracic spine MRI patients were prospectively examined in the period extending from August 2018 to April 2019. Both 1.5 and 0.35 Tesla MRI systems (Toshiba and Siemens Medical system) were applied to investigate patients with suspected intervertebral disc abnormalities at three MRI diagnostic centers in Khartoum, Sudan.

Results:

Out of the 120 patients, incidental extraspinal findings were found in 16 patients (13.3%). Various incidental findings (IFs) were seen, including renal cysts, liver mass, thyroid goiter, and pleural effusion. Out of these IFs, 37.5% were considered clinically significant.

Conclusions:

Various IFs were identified during a routine thoracic spine MRI, and approximately one-third of them were clinically significant. Therefore, it is essential for the reporting radiologists to pay attention to extraspinal findings while reporting thoracic spine MRI to avoid missing clinically significant findings.

Drug shortages in Saudi Arabia: Root causes and recommendations

Drug shortages are a multifaceted problem that has been recurring in Saudi Arabia over the past decade with its significant negative impact on patient care. However, there is a dearth of evidence about possible domestic reasons, if any, behind this recurring problem. Recently, the Pharmacy Education Unit at King Saud University College of Pharmacy has called for a meeting with multiple stakeholders from academia, pharmaceutical care, pharmaceutical industry, purchasing and planning, and regulatory bodies to unveil the root domestic causes of the drug shortages in the Kingdom. Four major topics were used to guide the discussion in this meeting, including: current situation of drug shortages in Saudi Arabia, major factors contributing to drug shortages, challenges and obstacles to improve drug supply, and stakeholders' recommendations to manage drug shortages. The meeting was audio-recorded and transcribed into verbatim by five authors. The text was then reviewed and analyzed to identify different themes by the first and third authors. Multiple causes were identified and several recommendations were proposed. The main domestic causes of drug shortages that were explored in this study included poor medication supply chain management, lack of government regulation that mandates early notification of drug shortages, a government procurement policy that does not keep pace with the changes in the pharmaceutical market, low profit margins of some essential drugs, weak and ineffective law-violation penalties against pharmaceutical companies and licensed drug importers and distributors, and overdependence on drug imports. The participants have also proposed multiple recommendations to address drug shortages. Policy makers should consider these factors that contribute to drug shortages in Saudi Arabia as well as the recommendations when designing future initiatives and interventions to prevent drug shortages.

Risk factors leading to peptic ulcer disease: systematic review in literature

This review is aiming to discuss the risk factors which lead to the occurrence of PUD during the period from July 2018 to August 2018. The present review was conducted by searching in Medline, Embase, Web of Science, Science Direct, BMJ journal and Google Scholar for, researches, review articles and reports, published over the past years. Books published on peptic ulcers and on the pathogenesis of human disease were also included., were searched up to August 2018 for published and unpublished studies and without language restrictions, the selected studies were summarized and un reproducible studies were excluded. If several studies had similar findings, we randomly selected one or two to avoid repetitive results. On the basis of findings and results this review found the H. Pylori and the use of NSAIDs are the most common risk factors for developing PUD, and also the genetic, stress and comorbidity increase the risk of PUD occurrence so successful eradication and prevention of the risk factors should be conducted to prevent the presence of PUD and is complication.

Genuine modified Bernstein-Durrmeyer operators

The present paper deals with genuine Bernstein-Durrmeyer operators which preserve some certain functions. The rate of convergence of new operators via a Peetre [Formula: see text]-functional and corresponding modulus of smoothness, quantitative Voronovskaya type theorem and Grüss-Voronovskaya type theorem in quantitative mean are discussed. Finally, the graphic for new operators with special cases and for some values of n is also presented.

Remediation of Cu(II), Ni(II), and Cr(III) ions from simulated wastewater by dendrimer/titania composites

Generation 4 polyamidoamine (PAMAM) dendrimers with ethylenediamine cores (G4-OH) were immobilized on titania (TiO(2)) and examined as novel metal chelation materials. Characterization results indicate both the effective immobilization of dendrimers onto titania and retention of the dendrimer on titania following remediation. The effective remediation of Cu(II), Ni(II), and Cr(III), which are model pollutants commonly found in industrial electroplating wastewater, is demonstrated in this work. Important parameters that influence the efficiency of metal ion removal were investigated; e.g. solution pH, retention time, metal ion concentration, and composite material dosage. Metal ion removal was achieved over a wide metal concentration range within a 1 h equilibration time. Maximum metal ion removal was achieved at pH ≥7 for both Cu(II) and Cr(III), and pH ≥9 for Ni(II). Further, the dendrimer/titania composite materials were even more effective when metal ion mixtures were tested. Specifically, a dramatic increase was observed for Ni(II) chelation when in a mixture was compared to a pure nickel solution. These findings suggest new strategies for improving metal ion removal from industrial wastewater.