Decellularization of Skin Tissue

Biomaterials science encompasses elements of medicine, biology, chemistry, materials, and tissue engineering. They are engineered to interact with biological systems to treat, augment, repair, or replace lost tissue function. The choice of biomaterial depends on the procedure being performed, the severity of the patient's condition, and the surgeon's preference. Prostheses made from natural-derived biomaterials are often derived from decellularized extracellular matrix (ECM) of animal (xenograft) or human (allograft) origin. Advantages of using ECM include their resemblance in morphology and three-dimensional structures with that of tissue to be replaced. Due to this, scientists all over are now focusing on naturally derived biomaterials which have been shown to possess several advantages compared to synthetic ones, owing to their biocompatibility, biodegradability, and remodeling properties. Advantages of a naturally derived biomaterial enhance their application for replacement or restoration of damaged organs/tissues. They adequately support cell adhesion, migration, proliferation, and differentiation. Naturally derived biomaterials can induce extracellular matrix formation and tissue repair when implanted into a defect by enhancing attachment and migration of cells from surrounding environment. In the current chapter, we will focus on the natural and synthetic dermal matrix development and all of the progress in this field.

A randomized controlled trial of complete bed rest versus ambulation in the management of proteinuric hypertension during pregnancy

Forty patients participated in a randomized controlled trial of complete bed rest versus ambulation as desired in the management of proteinuric hypertension during pregnancy. Daily increases in serum human placental lactogen and oestriol concentrations were greater in the rested group. An especially 'at risk' group of 10 patients with both hyperuricaemia and severe fetal growth retardation was identified. Strict confinement to bed in these cases seemed to encourage the development of the premonitory symptoms of eclampsia, but was associated with a better prognosis for the fetus.

The effect of rest and ambulation on plasma urea and urate levels in pregnant women with proteinuric hypertension

Plasma urea and urate concentrations were determined daily for up to seven days in 40 pregnant women who had been admitted to hospital because of proteinuric hypertension and who were then allocated at random to either complete rest in bed or to being allowed to move freely in the ward. Neither management was superior to the other in improving renal function. The prognostic significance of plasma urea and urate concentrations to maternal and fetal outcome was confirmed.

A double-blind trial of single-dose chemoprophylaxis with co-trimoxazole during vaginal hysterectomy and repair

Twenty-five patients received 10 ml co-trimoxazole (800 mg sulphamethoxazole and 160 mg trimethoprim) and 25 a placebo by intravenous infusion during one hour from the commencement of surgery for vaginal hysterectomy with anterior colporrhaphy and posterior colpo-perineorrhaphy. Single-dose chemoprophylaxis with co-trimoxazole was shown to be effective in reducing the incidence of postoperative febrile morbidity and urinary tract infection, especially that caused by Proteus species.

A randomized controlled trial of a short course of cephaloridine in the prevention of infection after abdominal hysterectomy

One hundred patients took part in a randomized controlled trial to test the efficacy of three 1 g doses of cephaloridine in preventing infection after abdominal hysterectomy. The first dose was given as an intravenous bolus at the commencement of surgery and the second and third as intramuscular injections 6 and 12 hours later. Given in this way, cephaloridine was found to be very effective in preventing febrile morbidity, abdominal wound infection and urinary tract infection. It was less effective in preventing pelvic wound infection and postoperative colonization of the vagina with Escherichia coli.

Fetal well-being in gravidas with diminished fetal activity at term

Twenty-five patients reporting a marked diminution in fetal activity at term in otherwise normal pregnancies were compared with 25 controls, matched for age, parity, and other factors, in whom movements were reported to be vigorous. Fetal well-being was assessed by maternal serum human placental lactogen concentration, maternal urinary estriol excretion, and fetal scalp blood acid-base values and hemoglobin concentration. Fetal biologic maturity was assessed by liquor creatinine concentration, percentage of orange cells on Nile blue staining, and "shake" testing. The 2 groups of patients showed no difference in fetoplacental well-being or degree of fetal biologic maturity.

A double-blind trial of single-dose chemoprophylaxis with co-trimoxazole during total abdominal hysterectomy

Thirty patients received 10 ml co-trimoxazole and 29 a placebo by intravenous infusion during one hour from induction of anaesthesia for total abdominal hysterectomy. The incidence of postoperative urinary tract infections was significantly lower in patients who had received co-trimoxazole. Co-trimoxazole was also found to inhibit postoperative colonization of the upper vagina with Escherichia coli. The incidences of postoperative pyrexia (38 degrees C or over) and both early and late abdominal wound abscess formation were almost identical in the two groups of patients.

Absence of upper limbs (amelia) in surviving intrauterine twin after salpingectomy for ectopic pregnancy

A patient is described who had simultaneous tubal and intrauterine pregnancies. The tubal pregnancy was treated by salpingectomy at 51 days after the onset of the last menstrual period. The surviving twin was born after 42 weeks gestation and had no upper limbs (amelia).

A randomized controlled trial of bed rest and sedation or normal activity and non-sedation in the management of non-albuminuric hypertension in late pregnancy

One hundred and thirty-five patients took part in a randomized controlled trial designed to determine whether bed rest and sedation are of any general benefit to either the mother or the baby in pregnancies complicated by mild non-albuminuric and non-symptomatic hypertension after the 28th week. The results suggest that they are not.

A randomised controlled trial of an oral solution of prostaglandin E2 and oral oxytocin used immediately after low amniotomy for induction of labour in the presence of a favourable cervix

A randomised controlled trial was carried out in 50 primigravidae and 50 multigravidae to compare the effectiveness in induction of labour after low amniotomy of prostaglandin E2, given as an oral solution, and oxytocin, given as buccal tablets. The results showed that in dosages recommended by the manufacturers, both oxytocic preparations were almost equally effective. With oral oxytocin, once labour had been established and dosage was left to the discretion of the staff, there appeared to be a potentially dangerous tendency to continue giving large doses despite adequate uterine contractions. The authors comment that this was probably the reason why oxytocin-treated multigravidae having normal deliveries within 24 hours had labours significantly shorter on average than those of other successfully induced patients.

Maternal assessment of fetal activity in small-for-dates infants

Fifty consecutive obstetric cases have been analyzed in which there was a clear history of either vigorous or reduced fetal activity during the week preceding delivery resulting in the birth of an infant weighing 2.5 kg or less after the 37th week. Especially in such hypertensive pregnancies, a maternal history of reduced overall fetal activity is very suggestive of impending fetal death, while a history of vigorous fetal activity tends to denote that the fetus is in no immediate danger. A plea is made for a greater awareness of this econimical "test" of fetal well-being. It is suggested that in some circumstances both impaired fetal growth and reduced fetal activity may be teleologic adaptations to the threat of a negative energy balance.