Advancements and Challenges in Hydrogel Engineering for Regenerative Medicine

This manuscript covers the latest advancements and persisting challenges in the domain of tissue engineering, with a focus on the development and engineering of hydrogel scaffolds. It highlights the critical role of these scaffolds in emulating the native tissue environment, thereby providing a supportive matrix for cell growth, tissue integration, and reducing adverse reactions. Despite significant progress, this manuscript emphasizes the ongoing struggle to achieve an optimal balance between biocompatibility, biodegradability, and mechanical stability, crucial for clinical success. It also explores the integration of cutting-edge technologies like 3D bioprinting and biofabrication in constructing complex tissue structures, alongside innovative materials and techniques aimed at enhancing tissue growth and functionality. Through a detailed examination of these efforts, the manuscript sheds light on the potential of hydrogels in advancing regenerative medicine and the necessity for multidisciplinary collaboration to navigate the challenges ahead.

Advancements in Cellulose-Based Superabsorbent Hydrogels: Sustainable Solutions across Industries

The development of superabsorbent hydrogels is experiencing a transformative era across industries. While traditional synthetic hydrogels have found broad utility, their non-biodegradable nature has raised environmental concerns, driving the search for eco-friendlier alternatives. Cellulose-based superabsorbents, derived from sustainable sources, are gaining prominence. Innovations include biodegradable polymer hydrogels, natural cellulose-chitosan variants, and cassava starch-based alternatives. These materials are reshaping agriculture by enhancing soil fertility and water retention, serving as potent hemostatic agents in medicine, contributing to pollution control, and providing eco-friendly construction materials. Cellulose-based hydrogels also offer promise in drug delivery and hygiene products. Advanced characterization techniques aid in optimizing their properties, while the shift towards circular economy practices further highlights sustainability. This manuscript provides a comprehensive overview of these advancements, highlighting their diverse applications and environmental benefits.

Enhancing Therapeutic Efficacy of Curcumin: Advances in Delivery Systems and Clinical Applications

Curcumin, a potent active compound found in turmeric and Curcuma xanthorrhiza oil, possesses a wide range of therapeutic properties, including antibacterial, anti-inflammatory, antioxidant, and wound healing activities. However, its clinical effectiveness is hindered by its low bioavailability and rapid elimination from the body. To overcome these limitations, researchers have explored innovative delivery systems for curcumin. Some promising approaches include solid lipid nanoparticles, nanomicelle gels, and transdermal formulations for topical drug delivery. In the field of dentistry, curcumin gels have shown effectiveness against oral disorders and periodontal diseases. Moreover, Pickering emulsions and floating in situ gelling systems have been developed to target gastrointestinal health. Furthermore, curcumin-based systems have demonstrated potential in wound healing and ocular medicine. In addition to its therapeutic applications, curcumin also finds use as a food dye, contraception aid, corrosion-resistant coating, and environmentally friendly stain. This paper primarily focuses on the development of gel compositions of curcumin to address the challenges associated with its clinical use.

High-Performing Conductive Hydrogels for Wearable Applications

Conductive hydrogels have gained significant attention for their extensive applications in healthcare monitoring, wearable sensors, electronic devices, soft robotics, energy storage, and human-machine interfaces. To address the limitations of conductive hydrogels, researchers are focused on enhancing properties such as sensitivity, mechanical strength, electrical performance at low temperatures, stability, antibacterial properties, and conductivity. Composite materials, including nanoparticles, nanowires, polymers, and ionic liquids, are incorporated to improve the conductivity and mechanical strength. Biocompatibility and biosafety are emphasized for safe integration with biological tissues. Conductive hydrogels exhibit unique properties such as stretchability, self-healing, wet adhesion, anti-freezing, transparency, UV-shielding, and adjustable mechanical properties, making them suitable for specific applications. Researchers aim to develop multifunctional hydrogels with antibacterial characteristics, self-healing capabilities, transparency, UV-shielding, gas-sensing, and strain-sensitivity.

Advancements and Applications of Injectable Hydrogel Composites in Biomedical Research and Therapy

Injectable hydrogels have gained popularity for their controlled release, targeted delivery, and enhanced mechanical properties. They hold promise in cardiac regeneration, joint diseases, postoperative analgesia, and ocular disorder treatment. Hydrogels enriched with nano-hydroxyapatite show potential in bone regeneration, addressing challenges of bone defects, osteoporosis, and tumor-associated regeneration. In wound management and cancer therapy, they enable controlled release, accelerated wound closure, and targeted drug delivery. Injectable hydrogels also find applications in ischemic brain injury, tissue regeneration, cardiovascular diseases, and personalized cancer immunotherapy. This manuscript highlights the versatility and potential of injectable hydrogel nanocomposites in biomedical research. Moreover, it includes a perspective section that explores future prospects, emphasizes interdisciplinary collaboration, and underscores the promising future potential of injectable hydrogel nanocomposites in biomedical research and applications.

Cryogels: Advancing Biomaterials for Transformative Biomedical Applications

Cryogels, composed of synthetic and natural materials, have emerged as versatile biomaterials with applications in tissue engineering, controlled drug delivery, regenerative medicine, and therapeutics. However, optimizing cryogel properties, such as mechanical strength and release profiles, remains challenging. To advance the field, researchers are exploring advanced manufacturing techniques, biomimetic design, and addressing long-term stability. Combination therapies and drug delivery systems using cryogels show promise. In vivo evaluation and clinical trials are crucial for safety and efficacy. Overcoming practical challenges, including scalability, structural integrity, mass transfer constraints, biocompatibility, seamless integration, and cost-effectiveness, is essential. By addressing these challenges, cryogels can transform biomedical applications with innovative biomaterials.

Common polymorphisms of protein tyrosine phosphate non-receptor type 2 gene are not associated with risk of Crohn’s disease in Indian

BACKGROUND

Multiple genetic risk factors for Crohn’s disease (CD) have been identified. However, these observations are not consistent across different populations. The protein tyrosine phosphate non-receptor type 2 (PTPN2) gene plays a role in various aspects of host defense including epithelial barrier function, autophagy, and innate and adaptive immune response. Two common polymorphisms in the PTPN2 gene (rs2542151 and rs7234029) have been associated with risk of CD in Western countries.

AIM

To evaluate the association of PTPN2 gene polymorphisms with risk of CD in Indian population.

METHODS

We conducted a prospective case-control study. Patients with CD were recruited, and their clinical and investigation details were noted. Controls were patients without organic gastrointestinal disease or other comorbid illnesses. Two common polymorphisms in the PTPN2 gene (rs2542151 and rs7234029) were assessed. DNA was extracted from peripheral blood samples of cases and controls and target DNA was amplified using specific sets of primers. The amplified fragments were digested with restriction enzymes and the presence of polymorphism was detected by restriction fragment length polymorphism. The frequency of alleles was determined. The frequencies of genotypes and alleles were compared between cases and controls to look for significant differences.

RESULTS

A total of 108 patients with CD (mean age 37.5 ± 12.7 years, females 42.6%) and 100 controls (mean age 39.9 ± 13.5 years, females 37%) were recruited. For the single nucleotide polymorphism (SNP) rs7234029, the overall frequency of G variant genotype (AG or GG) was noted to be significantly lower in the cases compared to controls (35.2% vs 50%, P = 0.05). For the SNP rs2542151, the overall frequency of G variant genotype (GT or GG) was noted to be similar in cases compared to controls (43.6% vs 47%, P = 0.73). There were no significant differences in minor allele (G) frequency for both polymorphisms between the cases and controls. Both the SNPs had no significant association with age of onset of illness, gender, disease location, disease behaviour, perianal disease, or extraintestinal manifestations of CD.

CONCLUSION

Unlike observation form the West, polymorphisms in the PTPN2 gene (rs7234029 and rs2542151) are not associated with an increased risk of developing CD in Indian patients.

Clinical profile and outcome of chronic pancreatitis in children

OBJECTIVE

To evaluate the etiology, presentation, complications and management of chronic pancreatitis in children.

DESIGN

Retrospective chart review.

SETTING

Gastroenterology department at Christian Medical College and Hospital, Vellore, India between January 2005 and December 2010.

PARTICIPANTS

99 Children (>18 yrs) diagnosed with chronic pancreatitis based on clinical and imaging features.

MAIN OUTCOME MEASURES

Etiology, clinical presentation, complications and management of chronic pancreatitis in children.

RESULTS

Of 3887 children who attended the Gastroenterology department, 99(2.5%) had chronic pancreatitis, of which 60 (60.6%) were males. In 95(95.9%) patients no definite cause was detected and they were labeled as Idiopathic chronic pancreatitis. All patients had abdominal pain, while 9(9.1%) had diabetes mellitus. Of the 22 children tested for stool fat, 10(45.5%) had steatorrhea. Pancreatic calcification was seen in 69 (69.7%). 68 (71.6%) patients with idiopathic chronic pancreatitis had calcification. Calcific idiopathic chronic pancreatitis was more frequent in males (67.6% vs. 48.1%, P=0.07), and was more commonly associated with diabetes mellitus (13.2% vs. none, P=0.047) and steatorrhea (61.5% vs. 16.7%, P=0.069). Pseudocyst (17.1%) and ascites (9.1%) were the most common complications. All children were treated with pancreatic enzyme supplements for pain relief. 57 patients were followed up. With enzyme supplementation, pain relief was present in 32 (56.1%) patients. Of those who did not improve, 10 underwent endotherapy and 15 underwent surgery. Follow up of 8 patients who underwent endotherapy, showed that 5 (62.5%) had relief. Follow up of 11 patients who underwent surgery showed that only 3 (27%) had pain relief. There was no death.

CONCLUSIONS

Idiopathic chronic pancreatitis is the predominant form of chronic pancreatitis in children and adolescents. It can present with or without calcification. The calcific variety is an aggressive disease characterized by early morphological and functional damage to the pancreas.

Dried papaya skin as a dietary ingredient for broiler chickens

The chemical composition of dried papaya (Carica papaya) skin (DPS) was determined and its potential as a dietary ingredient for broiler chickens was investigated at dietary concentrations of 0, 40, 80 and 120g/kg. DPS was found to give similar food consumption, food conversion efficiency, survivability and meat yields (except male liver weight) to a control diet when used up to 120 g/kg of diet. Weight gain tended to increase with dietary concentration of DPS up to 80 g/kg. It was concluded that DPS could safely be used up to 120 g/kg in the diet of broiler chickens.

Effects of dietary tamarind on cholesterol metabolism in laying hens

An experiment was conducted to evaluate the potential for dietary tamarind to alter serum and egg yolk cholesterol concentrations and overall performance in different layer strains. Thirty, 43-wk-old, Hisex Brown, ISA Brown, Lohmann Brown, Starcross Brown, Babcock B-300, and Starcross-579 strains (5 hens per strain) were fed diets supplemented with 0 (control), 2, 4, 6, or 8% oven-dried tamarind for 6 wk. Egg production, egg mass, and efficiency of feed utilization followed a quadratic response with a maximum when the diet contained 2% tamarind and a minimum when 8% tamarind was fed (P < 0.05). There were no differences (P > 0.05) among strains for egg production, egg weight, yolk weight, egg mass, feed consumption, or feed efficiency. Yolk weight increased linearly (P < 0.05) with increasing levels of dietary tamarind in wk 1, 2, and 3 as well as when averaged over 6 wk. Egg yolk cholesterol concentrations were not affected by dietary tamarind. Serum cholesterol concentrations, however, decreased quadratically with increasing levels of dietary tamarind (P < 0.05). It was concluded that 2% supplemental dietary tamarind could decrease serum cholesterol concentrations and increase layer performance.

Effects of dietary garlic on cholesterol metabolism in laying hens

Experiments were conducted to evaluate the potential for dietary garlic to influence egg yolk cholesterol concentrations and overall performance in different layer strains. Thirty-six, 28-wk-old, Hisex Brown,Isa Brown, Lohmann, Starcross, Babcock, and Starcross-579 strains (six hens per strain) were fed diets supplemented with 0 (control), 2, 4, 6, 8, or 10% sun-dried garlic paste for 6 wk. There were no differences (P > 0.05) among diets or strains in egg weight, egg mass, feed consumption, feed efficiency, and BW gain as averaged over 6 wk. Yolk weight, however, responded quadratically with increasing levels of dietary garlic and differed among strains (P < 0.05). Egg production and yolk weights were significantly higher in the Babcock strain in comparison with other strains. Serum and egg yolk cholesterol concentrations decreased linearly (P < 0.05) with increasing levels of dietary garlic. Serum and egg yolk cholesterol concentrations also differed among different strains (P < 0.05). It was concluded that garlic paste in the diets of laying hens reduced serum and yolk cholesterol concentrations. It was also concluded that dietary garlic paste had no adverse effects on layer performance.

Bedside ultrasound: a useful tool for the on-call urologist?

OBJECTIVE

To assess the accuracy and benefit of urgent bedside ultrasound scanning in urological emergencies by urology trainees.

METHODS

In this prospective study, 111 patients (86 acute flank pain, 15 renal failure, 10 haematuria) referred as urological emergencies, were scanned for urinary tract abnormalities at the bedside, by a trainee urologist, over 18 months. The ultrasound findings were compared with the results of imaging performed by a consultant radiologist and its influence on clinical management analysed.

RESULTS

Bedside ultrasound proved life saving in 5 patients (2 pyonephrosis, 2 leaking aneurysms, one bilateral ureteric injury). It significantly influenced management in 11 patients, excluded obstruction in the presence of infection.in 13 patients, helped in early diagnosis in 32 patients and ruled out gross urological pathology in 28 patients. It was misleading in 22 patients, mainly with ureteric colic (where the timing of the test can affect the findings), though the outcome was not adversely affected in any. Bedside ultrasound was reasonably accurate (sensitivity 81% and specificity 92%).

CONCLUSIONS

Bedside ultrasound is a useful tool to help the decision-making in urological emergencies and reasonably accurate in hands of a trainee urologist. It is especially helpful for excluding obstruction in presence of infection or renal failure. However it has inherent limitations in assessing acute ureteric colic.

Use of dried papaya skin in the diet of growing pullets

1. The chemical composition of dried papaya (Carica papaya) skin (DPS) was determined and the effect of diets containing different concentrations of this ingredient (0, 30, 60 and 90 g/kg) was studied using growing pullets as experimental animals. 2. Crude protein concentration was determined to be 229 g/kg and metabolisable energy content was estimated to be 6.4 MJ/kg. 3. Use of DPS in the diet up to 90 g/kg did not produce any significant difference in weight gain, food intake, food conversion and protein efficiency when compared with birds that received the control diet. 4. Survivability of growing pullets fed on DPS was 100%, as in the control group. 5. It was concluded that DPS can safely be used up to 90 g/kg in the diet of growing pullets.

Influence of dietary osteolathyrogens on the eggshell quality of laying hens

1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 or 0.4 g/kg or beta-aminopropionitrile fumarate at 0.5 or 0.6 g/kg diet to examine their effects on eggshell quality. 2. Shell quality characteristics considered for evaluation were shell surface area, shell thickness, shell weight, percentage shell, shape index and the specific gravity of eggs. Measurement of shell quality traits revealed that the hens fed osteolathyrogens laid eggs with significantly lower specific gravities and proportion of shell by weight. These differences were not explained by differences in shell thickness or weight or the shape index of eggs. 3. It was concluded that osteolathyrogens cause hens to lay eggs with poor shell quality and such eggs are weak and fragile.

Use of four types of litter for rearing broilers

1. One hundred and forty four Shaver broiler chicks (Starbro 15) were reared from 4 d to 56 d of age on 4 types of litter: sawdust, paddy straw, sand and rice husk each spread to a depth of 75 mm. 2. Birds reared on rice husk litter showed the greatest food consumption, greatest weight gain, best food conversion efficiency and scored highest in production number. 3. Survivability was also highest with rice husk group (94.4%) but differences in this variable were not thought to be attributable to types of litter. 4. Breast blisters were found only in birds reared on sand (8.3%). 5. It was concluded that rice husk is a suitable litter for rearing broilers on the floor, particularly in paddy-growing countries.

Influence of dietary osteolathyrogens on the ultrastructure of shell and membranes of eggs from laying hens

1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 g/kg or beta-aminopropionitrile fumarate at 0.6 g/kg, to examine their effects upon the ultrastructure of shell and shell membranes by scanning electron microscopy. 2. Effects of the 2 lathyrogens were similar. Compared with the highly-branched network of fine fibres in normal membranes, there is widespread lack of separation of fibres in lathyritic specimens and hence, uneven distribution of nucleation sites. Pores are also uneven in size and distribution, which can account for increased permeability. 3. Establishment between shell and membranes is reduced. Within the cone layer both type A and type B mammillary bodies occur. Large interstitial spaces and late fusion of the palisade layer indicate reduced resistance to fracture.

Use of rice husk litter at different depths for broiler chicks during summer

1. Four groups of 36 one-day-old broiler chicks were reared for 8 weeks during summer on rice husk litter spread to depths of 20, 30, 40 or 50 mm. 2. The depth of the litter did not significantly affect live weight gain, food consumption, food conversion ratio, liveability or production number. 3. It was concluded that rice husks can be used as litter at depths of between 20 and 50 mm during summer to raise broilers without affecting performance.

Comparison of the effects of two lathyrogens on the reproductive system of the laying hen

The effects of two lathyrogens (beta-aminopropionitrile and semicarbazide) on the reproductive system of the laying hen were compared by measuring the changes in the ovary and oviduct associated with a diminished egg production rate. The laying hens were fed diets containing either beta-aminopropionitrile, the toxic constituent of certain legume seeds in the genus Lathyrus or semicarbazide to induce lathyrogenic effects in which reduced egg production was one of the toxic effects. The gross examination of the reproductive system of the hens revealed that ovarian activity was greatly impaired. The reduced egg production after feeding beta-aminopropionitrile was due to the reduced growth rate of the ovary, and in the case of semicarbazide, to the atresia of large yolky follicles.

Lathyrism in laying hens and increases in egg weight

The cause of the increased egg weight in hens with lathyrism was investigated by feeding laying birds with diets containing beta-aminopropionitrile, the toxic principle of certain legume seeds in the genus Lathyrus. There was a significant increase (P less than 0.01) in the amount of albumen in the egg owing to an increased formation of thin white. The water permeability of the shell membranes demonstrated an increased porosity and a loss of tensile strength which contributed not only to a high water uptake but also to abnormalities of the shape of eggs during 'plumping'. It was concluded that a defect in the shell membrane protein system alters the membrane's general properties and that the increased egg weight in lathyrism is a result of the defect.

The clinical presentation of Chlamydia trachomatis in a urological practice

Fifty-nine men with Chlamydia trachomatis (CT) infection have been studied. Epididymitis was the most common presentation (26) compared with urethritis (8) and prostatitis (9). Only 13 patients gave a history of a urethral discharge. Fifteen of 21 female consorts screened were CT positive and 13 of these were asymptomatic. This demonstrates the major aetiological role of CT in lower genitourinary infection and indicates the importance of screening and treating consorts.

Preliminary report on use of depot formulation of LHRH analogue ICI 118630 (Zoladex) in patients with prostatic cancer

A study was conducted of the response of the pituitary-testicular axis to two different methods of administration of the luteinising hormone releasing hormone (LHRH) analogue ICI 118630 (Zoladex) in patients with prostatic cancer. The analogue was given by continuous infusion to four previously untreated patients with prostatic cancer for 60 days (group 1). Subsequently a further four patients were given a depot formulation of the same analogue by subcutaneous injection once every 28 days (group 2). Both methods of administration produced similar, successful suppression of luteinising hormone (LH) associated with a reduction of testosterone to castrate concentrations. The median basal testosterone concentrations before treatment in groups 1 and 2 were 20.6 and 14.1 nmol/l (5.94 and 4.07 ng/ml) respectively; these were reduced to 1.4 and 1.1 nmol/l (0.40 and 0.32 ng/ml) within four weeks of the start of treatment. The median basal LH concentration in groups 1 and 2 were 7.9 and 16.6 IU/1 respectively, which were suppressed to 2.6 and 2.4 IU/1 by four weeks. The suppression of LH and testosterone was maintained with continuous subcutaneous infusion for up to 60 days in group 1, and by subsequent injections of the depot every 28 days in group 2. The use of depot preparation of an LHRH analogue to suppress gonadotrophin and sex hormone secretion offers the convenience of once monthly injections when LHRH analogues are required for the long term treatment of elderly patients with prostatic cancer and children with precocious puberty.

Zinc in post prostatic massage (VB3) urine samples: a marker of prostatic secretory function and indicator of bacterial infection

The value of biochemical examination of post-prostatic massage (VB3) urine samples has been investigated. Measurement of zinc levels provides a good marker of prostatic secretory function. In the absence of prostatic carcinoma findings of greater or equal to 100 micrograms zinc in VB3 urines is strong evidence (2% false negatives) of an absence of infectious or inflammatory prostatic disease. Less than 40 micrograms of zinc is suggestive (14% false positives) of prostatitis. There is little need to consider the endogenous urinary zinc levels. This simple test should be of particular value in cases where an expressed prostatic secretion is not obtained (about 40% of this series of patients), when it would be a valuable adjunct to cytological and bacteriological examination of split urine samples.

Renal function and hypertension in primary hyperparathyroidism

Fifteen patients with histologically proven primary hyperparathyroidism have been investigated with special reference to renal function and the occurrence of hypertension. The patients have been followed up clinically, biochemically, and radiographically for a period of 8 months to 5 years after surgery. In all cases the serum-calcium levels returned to normal immediately after parathyroid adenectomy.

Satisfactory renal function was maintained in all but I of the cases who had had normal preoperative renal function tests. However, renal damage once established persisted and even progressed after parathyroid adenectomy. Renal function, therefore, did not improve after operation.

At follow-up examination a decrease in the number of renal calculi was found in only 2 cases. None of the patients showed formation of new renal calculi or increase in size of those present preoperatively.

Hypertension was present in 6 patients preoperatively. Six months after operation 2 more patients became hypertensive. Both of these patients had shown evidence of renal damage preoperatively. In another case the patient became normotensive 3 months after operation. The severity of renal functional impairment did not bear any relationship to the degree of hypertension although it is possible that the hypertension is secondary to the renal lesion.

Chemical composition of some medicinal plant products of indigenous origin

Chemical compositions of leaves of neem (Azadirachta indica), sajna (Moringa oleifera), arjun (Terminalia arjuna), tulsi (Ocimum sanctum), turmeric (Curcuma longa); rhizomes of ginger (Zingiber officinale) and turmeric; fruits of amla (Emblica officinalis), haritaki (Terminalia chebula), bohera (Terminalia belerica) and bulbs of garlic (Allium sativum) of indigenous origin were determined. Proximate and mineral components [Calcium (Ca), Phosphorus (P), Sodium (Na), Potassium (K), Magnesium (Mg), Copper (Cu), Zinc (Zn), Manganese (Mn)] were determined. Dry matter (DM) varied from 964g/kg in arjun leaves to 892g/kg in tulsi leaves. Sajna leaves were high in protein (240g/kg), whereas haritaki fruits were low (34g/kg). Highest amount of ether extract (EE) was found in turmeric rhizomes and the lowest in amla fruits. The crude fibre (CF) ranged from 134 g/kg in turmeric leaves to 7g/kg in garlic bulbs. Highest amounts of ash were found in tulsi leaves (136g/kg), whereas haritaki had 42g/kg. All the plant products had high Nitrogen Free Extract (NFE) and haritaki ranked the highest. Neem leaves contained the highest amount of Ca and Mg. Fruits had lower amounts of P than other products. K content ranged between 8510 ppm in turmeric leaves and 4190 ppm in arjun leaves. Tulsi leaves contain higher amounts of Na, whereas arjun leaves contained less. Tulsi leaves contain higher amount of Cu and Zn than other plant products. The Mn content ranged from 17 ppm in ginger to 780 ppm in garlic bulbs. Only sajna and neem leaves are considered as fair sources of protein. Such ingredients may be considered as good sources of Ca and Mg. DOI: 10.3329/bvet.v25i1.4616 Bangl. vet. 2008. Vol. 25, No. 1, 32-39