Prospectives and challenges of nano-tailored biomaterials-assisted biological molecules delivery for tissue engineering purposes

Nano carriers have gained more attention for their possible medical and technological applications. Tailored nanomaterials can transport medications efficiently to targeted areas and allow for sustained medication discharge, reducing undesirable toxicities while boosting curative effectiveness. Nonetheless, transitioning nanomedicines from experimental to therapeutic applications has proven difficult, so different pharmaceutical incorporation approaches in nano scaffolds are discussed. Then numerous types of nanobiomaterials implemented as carriers and their manufacturing techniques are explored. This article is also supported by various applications of nanobiomaterials in the biomedical field.

Hypothyroidism: morphological and metabolic changes in the testis of adult albino rat and the amelioration by alpha-lipoic acid

BACKGROUND

The objective of this study is to evaluate the influence of carbimazole- induced hypothyroidism on the testes of adult albino rats and the probable protective effect of alpha-lipoic acid (ALA).

MATERIALS AND METHODS

The rats were divided into four groups; control group, ALA group, carbimazole, and carbimazole + ALA groups. Rats were exposed to ALA (60 mg/kg body weight) or carbimazole (1.35 mg/kg body weight), or both, administered via gavages for 30 days.

RESULTS

Morphometric analysis revealed a significant decrease in tubular diameter, germinal epithelium thickness, and interstitial space as compared to the controls. Also, rats exposed to carbimazole showed a significant decline in testicular weight, sperm motility, and count. Additionally, deterioration of the testicular architecture was observed. ALA supplementation resulted in a significant improvement in the tubular diameter and germinal epithelium thickness, but no significant improvement regarding interstitial space was observed. Another observation was the significant decline in serum testosterone and follicle-stimulating hormone (FSH) in the carbimazole group, indicating reduced steroidogenesis. A significant reduction in reduced glutathione content was detected in the testes of the carbimazole group compared with the controls, while malonaldehyde concentration significantly increased. Conversely, ALA supplementation ameliorated the toxicity induced by hypothyroidism as illustrated by enhanced reproductive organ weights, testosterone, luteinizing hormone, and FSH levels, testicular steroidogenesis, and oxidative stress parameters.

CONCLUSIONS

Hypothyroidism altered testicular antioxidant balance and negatively affected spermatogenesis. On the other hand, ALA through its antioxidant properties alleviated testicular toxicity in carbimazole-exposed rats.

Elevated IgA antiphospholipid antibodies in healthy pregnant women in Sudan but not Sweden, without corresponding increase in IgA anti-β2 glycoprotein I domain 1 antibodies

Objective

The role of antiphospholipid antibodies (aPL) during apparently normal pregnancy is still unclear. IgA aPL are prevalent in populations of African origin. Our aim was to measure all isotypes of anticardiolipin (anti-CL) and anti–β₂ glycoprotein I (anti-β₂GPI) in healthy pregnant and non-pregnant women of different ethnicities.

Methods

Healthy Sudanese pregnant women (n = 165; 53 sampled shortly after delivery), 96 age-matched Sudanese female controls and 42 healthy pregnant and 249 non-pregnant Swedish women were included. IgA/G/M anti-CL and anti-β₂GPI were tested at one time point only with two independent assays in Sudanese and serially in pregnant Swedes. IgA anti-β₂GPI domain 1 and as controls IgA/G/M rheumatoid factor (RF), IgG anti–cyclic citrullinated peptide 2 (anti-CCP2) and anti–thyroid peroxidase (anti-TPO) were investigated in Sudanese females.

Results

Pregnant Sudanese women had significantly higher median levels of IgA anti-CL, IgA anti-β₂GPI (p < 0.0001 for both antibodies using two assays) and IgM anti-β₂GPI (both assays; p < 0.0001 and 0.008) compared with non-pregnant Sudanese. IgA anti-CL and anti-β₂GPI occurrence was increased among Sudanese pregnant women compared with national controls. No corresponding increase during pregnancy was found for IgA anti-β₂GPI domain 1 antibodies. Both IgG anti-CL and IgG control autoantibodies decreased during and directly after pregnancy among Sudanese. Serially followed Swedish women showed no changes in IgA aPL, whereas IgG/M anti-CL decreased.

Conclusions

IgA aPL are increased in Sudanese but not in Swedish women, without corresponding increase in IgA domain 1. Whether due to ethnicity and/or environmental influences the occurrence of IgA aPL during Sudanese pregnancies, and its clinical significance, is yet to be determined.

Vitamin D3 supplementation ameliorates ovariectomy-induced cardiac apoptotic and structural changes in adult albino rats

The effect of vitamin D on cardiac dysfunction after menopause is still under investigation. Therefore, we investigated the effect of vitamin D3 on cardiac apoptotic and structural changes in ovariectomized rats. Forty adult female albino rats were divided into 4 equal groups: sham rats, sham rats treated with vitamin D3, ovariectomized rats, and ovariectomized rats treated with vitamin D3 (500 IU/kg per day for 6 weeks, orally). Body mass, blood pressure, heart rate, and whole heart mass (WHM) were measured. Serum soluble receptors of advanced glycation end products (sRAGE), C-reactive protein, malondialdehyde, and total antioxidant capacity were estimated. Cardiac sections were stained with haematoxylin-eosin and Masson's trichrome stain. Fas and FasL apoptosis-related proteins were detected by immunohistochemistry. Vitamin D3 treatment significantly decreased ovariectomy-induced cardiac Fas and FasL apoptosis-related proteins, whole heart mass, body mass, C-reactive protein, and malondialdehyde accompanied by decreased inflammation and reduced collagen deposition between cardiac muscle fibres. However, vitamin D3 significantly increased total antioxidant capacity and sRAGE in ovariectomized and sham treated groups. Our findings suggest that vitamin D3 treatment can prevent ovariectomy-induced cardiac structural and apoptotic changes in rats via increasing sRAGE and antioxidant activity. Our results suggest that vitamin D3 has therapeutic effect against postmenopausal cardiovascular disease.

The effect of antidepressant drugs on thioacetamide-induced oxidative stress

OBJECTIVE

The aim of the present study was to investigate the effect of the serotonin selective reuptake inhibitors (SSRIs) fluoxetine and sertraline and the tricyclic drug imipramine on oxidative stress in the brain and liver caused by thioacetamide in rats.

MATERIALS AND METHODS

Drugs were administered orally once daily at doses of 10 and 20 mg/kg for two weeks prior to intraperitoneal injection of thioacetamide (300 mg/kg). Rats were euthanized 24 h after thioacetamide. Reduced glutathione (GSH), malondialdehyde (MDA) and nitric oxide were measured in brain and liver. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were measured in serum and histopathological evaluation of liver injury was performed.

RESULTS

The administration of thioacetamide increased MDA by 151.8% and 161.2%, increased nitric oxide by 57.2% and 63.9% and decreased GSH by -40.6% and -67% in the brain and liver, respectively. Thioacetamide markedly increased serum ALT, AST and ALP by 277.8, 80.8 and 121%, respectively. In the brain, MDA was decreased in rats treated with fluoxetine or sertraline. The level of GSH increased by fluoxetine and by the higher dose of sertraline. Nitric oxide in brain was unchanged by fluoxetine, but increased after sertraline at 20 mg/kg. Brain MDA was increased by imipramine, which also decreased brain nitrite level. In the liver, fluoxetine or sertraline treatment increased GSH and nitrite levels. MDA was also increased by either drug. The drugs markedly decreased ALT, but increased ALP in serum. Meanwhile, imipramine decreased liver nitric oxide levels (at the lower dose only -32.9%), markedly increased hepatic GSH, but did not change MDA level. Serum ALT decreased by imipramine (but AST and ALP showed no change). Histopathological and histochemical examinations indicated that thioacetamide-induced liver injury was not decreased after treatment with the antidepressant drugs.

CONCLUSIONS

In thioacetamide-treated rats, pretreatment with the SSRIs drugs fluoxetine and sertraline is associated with decreased lipid peroxidation in brain; liver peroxidation, however, is increased. Imipramine displayed opposite effects. The thioacetamide-induced hepatic damage was not reduced by fluoxetine, sertraline or imipramine.  

Biomechanics of the Birmingham hip resurfacing arthroplasty

The effects of the method of fixation and interface conditions on the biomechanics of the femoral component of the Birmingham hip resurfacing arthroplasty were examined using a highly detailed three-dimensional computer model of the hip. Stresses and strains in the proximal femur were compared for the natural femur and for the femur resurfaced with the Birmingham hip resurfacing. A comparison of cemented versus uncemented fixation showed no advantage of either with regard to bone loading. When the Birmingham hip resurfacing femoral component was fixed to bone, proximal femoral stresses and strains were non-physiological. Bone resorption was predicted in the inferomedial and superolateral bone within the Birmingham hip resurfacing shell. Resorption was limited to the superolateral region when the stem was not fixed. The increased bone strain observed adjacent to the distal stem should stimulate an increase in bone density at that location. The remodelling of bone seen during revision of failed Birmingham hip resurfacing implants appears to be consistent with the predictions of our finite element analysis.

Distribution of constitutive (COX-1) and inducible (COX-2) cyclooxygenase in postviral human liver cirrhosis: a possible role for COX-2 in the pathogenesis of liver cirrhosis

AIMS

Prostaglandins produced by the action of cyclooxygenases (COX) are important mediators of systemic vasodilatation and inflammation in liver cirrhosis. The aim of this study was to investigate the distribution of COX-1 and COX-2 in postviral cirrhosis.

METHODS

The immunohistochemical expression of the constitutive (COX-1) and the inducible (COX-2) isoenzymes was investigated in 15 patients with cirrhosis after hepatitis B and C infection; three normal control livers were also analysed.

RESULTS

COX-2 was absent from normal liver but was highly expressed in cirrhosis, mainly in the inflammatory, sinusoidal, vascular endothelial, and biliary epithelial cells. Low amounts of COX-1 were expressed in both normal and cirrhotic livers, exclusively in sinusoidal and vascular endothelial cells, with no differences seen between normal and cirrhotic livers.

CONCLUSIONS

COX-2 is overexpressed in liver cirrhosis, and possibly contributes to prostaglandin overproduction, which may be a major component of the inflammation and hyperdynamic circulation associated with cirrhosis. Because COX-2 is thought to contribute to tumour development, high COX-2 production could be a contributor to hepatocellular carcinoma development in cirrhosis. The finding of COX-2 and not COX-1 upregulation in cirrhosis could provide a possible new role for selective COX-2 inhibitors in reducing inflammation and minimising the occurrence of hepatocellular carcinoma in patients with cirrhosis.

Prevalence and correlates of childhood fears in Al-Ain, United Arab Emirates

The prevalence of fear was explored in 340 adolescents in Al-Ain, United Arab Emirates. More than 50% reported feeling extremely frightened of 6 out of 60 fear items surveyed. These items were: someone dying in the family (66.5%), parents getting divorced (65.3%), the devil (63.8%), breaking a religious law (61.5%), being kidnapped (53.2%) and being adopted (49.9%). The level of fear showed a significant positive correlation with female gender, parental death/divorce, living with a single parent/relatives, living in low income families and an adverse home environment. Nearly half of the children reported that the fear caused considerable distress and interfered with daily activities.

Experimental immune complex glomerulonephritis and the nephrotic syndrome in cats immunised with cationised bovine serum albumin

Membranous nephropathy was induced in four cats by repeated intravenous injections of 120 mg cationic bovine serum albumin (BSA, pI 9.5). All four cats developed diffuse granular deposits of IgG and C3 along the glomerular capillary walls as early as five weeks which persisted until the end of the experiment at 17 weeks. Ultrastructural studies revealed many subepithelial electron dense deposits. Two cats developed severe proteinuria and the nephrotic syndrome characterised by hypoalbuminaemia and oedema. An additional four cats received repeated injections of unmodified native BSA (pI 4.5) and remained basically normal. This is the first report of membranous nephropathy and the nephrotic syndrome in an experimental animal model which, unlike other animal models, is subject to the spontaneously occurring disease.

The acute phase reaction detected in dogs by concanavalin A binding

Using a kinetic turbidimetric assay based on the binding of serum glycoprotein to concanavalin A the acute phase reaction has been detected in dogs. Raised levels of glycoprotein were found in dogs which had undergone surgery, had been treated with bacterial endotoxin and had various inflammatory conditions.

Experimental immune complex glomerulonephritis in dogs receiving cationized bovine serum albumin

Eight 16-week-old dogs were used to induce immune complex glomerulonephritis by daily intravenous injections of 120 mg highly cationized bovine serum albumin (pI9.5). Of four control dogs, two received unmodified native anionic bovine serum albumin (pI 4.5) while the other two received only phosphate buffered saline. The renal glomeruli were examined by light, electron (transmission and scanning) and immunofluorescence microscopy at intervals from five to 11 weeks after the start of the injections. Animals receiving cationic antigen all developed generalised diffuse granular deposits of IgG and C3 along the capillary walls; these were detected as early as five weeks and continued until the termination of the experiment at 11 weeks. Ultrastructural studies revealed many electron dense deposits along the subepithelial regions of the glomerular basement membrane. The experimental disease resembled in many respects naturally occurring membranous nephropathy, the most common form of immune complex glomerulonephritis in dogs.