Comparative analysis of free vascularized fibula grafting and Ilizarov bone transport in management of segmental long bone defect of the lower limb: A systematic review and meta-analysis

Introduction

Reconstruction of segmental defects of long bones is a daunting task for surgeons. Bone transport with the help of Illizarov external fixator and vascularized free fibula flap are some of the most discussed and valid options for the same. Both techniques have their limitations and overlapping indications. However, there has been no objective evidence in the manner of a systematic review supporting one treatment method over the other.

Aim

This systemic review is aimed to compare the bony union, functional outcomes, and complications of Illizarov bone lengthening and free fibula flap performed for segmental bone defects of long bones of the leg.

Methods

A comprehensive search was done for all studies published before May 2023. Any observational study comparing bone transport based on Illizarov external fixator and free vascularized fibula grafting techniques for treating lower limb long bone segmental defects was entailed in this study.

Results

This systematic review comprised of five retrospective studies. A total of 96 patients were treated by the Illizarov-based bone transport technique and 72 patients were treated by the free vascularized fibula grafting technique. The free vascularized fibula grafting technique yielded a shorter mean time to union (average difference 9.3 months), relatively shorter external fixator time (average difference 5.32 months), and external fixator index (average difference 0.57 months/cm). However, there was no difference in terms of bony and functional outcomes between both techniques when used for the reconstruction of bony defects in the lower limb. Total number of complications was 68 % higher in bone transport with Illizarov external fixator. However, the rates of non-union didn't differ between the groups.

Conclusion

The free vascularized fibula grafting technique had a lesser time to bony union, shorter time for external fixator application, and lower incidence of complications. However, the functional and bony outcomes didn't differ between both techniques.

Level of evidence

Level 4.

Infectious Disease Markers in Blood Donors

BACKGROUND

The infectious disease markers for which blood donors are screened include anti-human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (HCV), rapid plasma reagin (RPR) card test for syphilis and malarial parasites.

METHODS

A total of 6751 donors were screened over three years to assess the prevalence of infectious disease markers. Screening for anti-HIV I and II, HBsAg and anti-HCV was carried out by enzyme linked immunosorbent assay (ELISA). Syphilis was tested using RPR card test. Malarial parasite was tested by detection of genus specific plasmodium lactate dehydrogenase.

RESULT

The overall seropositivity for anti-HIV I and II was nine (0.13%), for HBsAg 67 (0.99%), for anti-HCV 13 (0.19%) and for syphilis 42 (0.62%). No sample showed malarial parasites. There was no significant difference (p>0.05) in the seropositivity of various markers between voluntary and replacement donors. There was a significant decline (p<0.05) in the prevalence of seropositivity for HCV and syphilis, but not for HIV and HBsAg over the three year period of the study.

CONCLUSION

The prevalence of infectious disease markers was similar to that reported by other studies. However, no significant difference was seen in the marker positivity in voluntary and replacement donors, which is at variance from other studies.

Characterization of genetic polymorphism of the bovine lymphocyte antigen DRB3.2 locus in Kankrej cattle (Bos indicus)

Bovine lymphocyte antigen DRB 3.2 (BoLA-DRB3.2) gene encodes for the beta chain of the major histocompatibility complex (MHC) class II molecule in cattle, which is a glycoprotein present on the surface of antigen-presenting cells. This locus shows extensive polymorphism in it. The objective of the present study was to genotype the BoLA-DRB3.2 locus in Kankrej cattle (n = 50) by PCR-RFLP. Bovine DNA was isolated from aliquots of whole blood. Primers specific for exon 2 of the bovine lymphocyte antigen (BoLA)-DRB3 gene were used to amplify the region. The 304-bp amplified product of the DRB3 gene was separately digested with restriction endonucleases RsaI, BstYI, and Hae III. Twenty-four BoLA-DRB 3.2 alleles were identified with frequencies ranging from 1 to 22.0%. Twenty-one alleles of the total 24 alleles were similar to those reported earlier; 3 alleles were new and had not been reported previously. The allele BoLA-DRB3.2*34 occurred at the highest frequency of 22% (approx.) in the Kankrej animals studied. Six alleles (BoLA-DRB3.2 *34, *15, *06, *20, *37, and *20) accounted for almost 71% of the total alleles observed to be present in the Kankrej animals. All the new alleles observed were present at frequencies of 1%. The results obtained in the present study demonstrated that the BoLA DRB3.2 locus is highly polymorphic in the Kankrej cattle.

Genetic analysis of Ankamali pigs of India using microsatellite markers and their comparison with other domesticated Indian pig types

Ankamali pigs, the domesticated native pigs of Kerala province of India were genetically characterized using 23 FAO recommended microsatellite markers and were compared with other native Indian pig types and Large White pigs. Twenty-six blood samples were collected from genetically unrelated animals from their breeding tract and DNA was isolated by standard procedure of phenol/chloroform. The genomic DNA was amplified by polymerase chain reaction (PCR) at these 23 microsatellite loci, which were also used earlier to characterize Desi (North Indian) and Gahuri (North-East Indian) pigs, the other two native domesticated pig types of India. The PCR products were resolved by denaturing urea-polyacrylamide gel electrophoresis and alleles were visualized after silver nitrate staining. The data were analysed for allele size range, number of alleles, allelic frequencies, heterozygosity and polymorphism information content for each locus. The allele size range varied between 92-108 bp at locus S0026 and 280-296 bp at locus IGF-1. The total number of alleles varied between five (S0178 and S0386) and 11 (S0355). The mean observed and expected heterozygosities were found to be 0.74 +/- 0.09 and 0.83 +/- 0.03 respectively. In the neighbour-joining dendrogram based on D(A) genetic distances developed after 1000 bootstraps, the Ankamali pigs did not show genetic closeness either with other native Indian pig types or exotic Large White pigs with high bootstrap values indicating genetic distinctness of Ankamali pigs.

Possible Role of Neonatal Infection with the Asymptomatic Reassortant Rotavirus (RV) Strain I321 in the Decrease in Hospital Admissions for RV Diarrhea, Bangalore, India, 1988–1999

We sought to determine the proportion of rotavirus (RV) infections among children with severe diarrhea in Bangalore, India, and to determine the role of neonatal infection with the asymptomatic RV strain I321 in protection against subsequent RV diarrhea. At 2 major hospitals, there was a >42% decrease in diarrhea-specific admissions during the study period. At 6 hospitals, asymptomatic infections were found in 25%-50% of neonates, when screening was performed randomly, and in >58% of neonates, when screening was performed daily, with the majority of infections occurring within the first 7 days of life. All the RVs found in asymptomatic neonates were strain I321. A 24-month follow-up of a cohort of 44 children who had been neonatally infected with strain I321 and 28 children who had not (control group) revealed comparable rates of RV detection but a marked decrease in the number of RV diarrhea episodes in the strain I321-infected group (2.3%), compared with the control group (39.3%) (P<.0001). This preliminary study suggests a possible association between neonatal infection with strain I321 and protection against subsequent RV illness.

Evaluation of the genetic variability of 13 microsatellite markers in native Indian pigs

We analysed polymorphism of 13 microsatellites in two Indian domesticated pig types (North Indian and Northeast Indian). Heterozygosity, polymorphism information content, and probability of identity of two random individuals were calculated for all microsatellites in both types. The number of alleles observed at a locus varied between five and 12. The evaluated microsatellites exhibited a very high heterozygosity and polymorphism information content. The probability of identity of two random individuals from different populations taking into account all the 13 microsatellites was as low as 3.51 x 10(-19). On the basis of these results, we propose that these microsatellite markers may be used with reliability for studying the genetic diversity and for identification of individuals in Indian pig types.

Lack of neighborhood effects from a transcriptionally active phosphoglycerate kinase-neo cassette located between the murine beta-major and beta-minor globin genes

For the treatment of beta-globin gene defects, a homologous recombination-mediated gene correction approach would provide advantages over random integration-based gene therapy strategies. However, "neighborhood effects" from retained selectable marker genes in the targeted locus are among the key issues that must be taken into consideration for any attempt to use this strategy for gene correction. An Ala-to-Ile mutation was created in the beta6 position of the mouse beta-major globin gene (beta(6I)) as a step toward the development of a murine model system that could serve as a platform for therapeutic gene correction studies. The marked beta-major gene can be tracked at the level of DNA, RNA, and protein, allowing investigation of the impact of a retained phosphoglycerate kinase (PGK)-neo cassette located between the mutant beta-major and beta-minor globin genes on expression of these 2 neighboring genes. Although the PGK-neo cassette was expressed at high levels in adult erythroid cells, the abundance of the beta(6I) mRNA was indistinguishable from that of the wild-type counterpart in bone marrow cells. Similarly, the output from the beta-minor globin gene was also normal. Therefore, in this specific location, the retained, transcriptionally active PGK-neo cassette does not disrupt the regulated expression of the adult beta-globin genes. (Blood. 2001;98:65-73)

Effect of epidermal growth factor on steroidogenesis by caprine granulosa cells in culture: interaction with FSH

Besides gonadotrophins various peptide growth factors have been implicated in the ovarian folliculogenesis. In this study, the effect of epidermal growth factor (EGF) (0, 0.1, 1.0, 10ng/ml culture medium) on steroidogenesis by caprine granulosa cells at various stages of maturation was investigated using serum free culture medium. Caprine granulosa cells were obtained from ovarian follicles and classified into three classes: small (<3mm), medium (3-6mm) and large (>6mm in diameter). EGF (10ng/m culture medium) alone reduced estradiol secretion in granulosa cell from small, medium and large follicles by 62, 48 and 29%, respectively, as compared with control. This inhibition was 50, 36 and 21%, respectively, when EGF (10ng/ml culture medium) was applied in combination with FSH (100ng/ml culture medium). EGF alone stimulated the secretion of progesterone in granulosa cells from all the three categories of follicles only at highest dose tested (10ng/ml culture medium). FSH acted synergistically with EGF in stimulating progesterone secretion by cultured granulosa cells. EGF in combination with FSH (100ng/ml culture medium) significantly (P<0.05) stimulated progesterone secretion by cultured granulosa cells from all three categories of follicles even at the lowest dose (0.1ng/ml culture medium) tested. In conclusion, EGF significantly influences the steroidogenesis by caprine granulosa cells in vitro and may play important role in the follicular growth and maturation.

Induction of tissue factor procoagulant activity in myelomonocytic cells inoculated by the agent of human granulocytic ehrlichiosis

Human granulocytic ehrlichiosis (HGE) is a recently recognized rickettsial tick-borne febrile illness that may occasionally be complicated by coagulopathy. The agent of HGE (aHGE) is an obligate intracellular pathogen, which replicates in endosomes within neutrophils and their precursors. We hypothesized that aHGE might cause DIC via induction of monocyte tissue factor procoagulant activity (TF PCA). Peripheral blood mononuclear cells (PBMNC) and HL-60 cells were used to model the effect of aHGE infection on monocytes/macrophages. Mononuclear cells inoculated with aHGE in vitro demonstrated approximately a 12-15-fold increase in TF PCA, with peak activity occurring at 8-12 h. HL-60 cells inoculated with aHGE also manifested a 4-6 fold induction of TF PCA, with maximal activity occurring at about 8 h. By comparison, E. Coli lipopolysaccharide (LPS) also induced an increase in TF PCA of an equivalent magnitude, and with a similar time course. Induction of TF did not require inoculation of HL-60 cells with live organism, since heat-inactivated aHGE still stimulated TF PCA expression in the target cells. Furthermore, filtered supernatants from heat-inactivated organisms induced TF PCA suggesting that the effect is due to a soluble mediator produced by the organism. Although aHGE is a gram negative organism, the soluble mediator did not appear to be classic endotoxin in that the supernatants tested negative for endotoxin by the Limulus Amoebocyte assay, and polymixin had no inhibitory effect on aHGE supernatants. We conclude that aHGE induces cells of the myelo-monocytic lineage to synthesize TF, which may contribute to the clinical coagulopathy that can be observed in this condition. An atypical soluble mediator or cellular component of the organism appears to be critically important in TF induction by aHGE.

Effect of insulin-like growth factor-1 on steroidogenesis in cultured carp ovarian follicles: interactions with estradiol

The biological action of insulin like growth factor-1 (IGF-1) on follicular steroidogenesis during follicular development in common carp was examined. Studies were carried out by culturing small (1-2 mm diam.) and large (> 2 mm diam.) follicles. IGF-1 (0.3-100 ng/ml) had no effect on progesterone accumulation or aromatase activity during 48 hr culture of small follicles. Progesterone accumulation by large follicles was also unaffected by IGF-1 over the same period, although aromatase activity was stimulated in a dose dependent manner (8-fold increase over basal levels with a maximum stimulatory dose of 30 ng IGF-1/ml). In contrast, small and large follicles responded to IGF-1 in terms of both progesterone accumulation and aromatase activity after longer periods of culture (4 days for progesterone and 6 days for aromatase). Concurrent treatment of small follicles with estradiol (10(-7) M) enhanced the action of IGF-1 on both indices of steroidogenesis and advanced the time at which IGF-1 stimulated activity was first detectable. The effect of estradiol on follicular IGF-1 responsiveness were independent of cell number. In summary, these results demonstrate varied actions of IGF-1 carp ovarian follicular steroidogenesis in vitro. The results indicate that carp follicles acquire responsiveness to IGF-1 in terms of aromatase activity during follicular development in vivo and that estradiol can induce the response in vitro. The results also suggest that estrogen and progesterone biosynthesis by cultured carp ovarian follicles is differentially regulated by IGF-1. Together, these results provide new insights into the biological actions of IGF-1 in fish ovary.

Hepatic pyridine nucleotides content in rat--a better indicator for determining available niacin values of food

After 10 days depletion period with niacin free diet, weanling rats were repleted with either reference diets containing niacin at four levels (2, 4, 8 and 12 mg/kg diet) or test diets containing test material at two levels as source of niacin. Gains in body weight and hepatic pyridine nucleotides content increased with increase in niacin intake. The correlation coefficient for hepatic pyridine nucleotides content and niacin intake was 0.98, whereas for weight gain and niacin intake was 0.89. Dried skim milk and pearl millet were taken as test materials. Dried skim milk with most of its niacin in free form showed 98% niacin equivalent to be bioavailable whereas in pearl millet niacin was in bound form and bioavailability equivalent was only 48 per cent.

Early results of direct repair of aortic interruption by the lateral approach

Eleven consecutive patients were operated on for interruption of the aortic arch by direct aortoplasty through a lateral approach. Median age was 5 days and median weight, 3.52 kg. All received prostaglandin E. Four of the 11 required preoperative ventilatory and inotropic support. Diagnosis was by echocardiography with one confirmed by angiography. There were five type B and six type A interruptions. Aortic continuity was achieved through a left thoracotomy. The aorta and great vessels were mobilized, and after clamps were placed above and below the interruption, ductal tissue was excised and direct anastomosis performed. There was one death from sepsis. One patient died of pulmonary hypertension early after the second operation for correction of other anomalies, and 1 died of hypoplastic lungs after 6 months of ventilation. In 10 of the 11 patients there was no postoperative gradient. Palliative staged approach for correction of this malformation is advocated. The need for bypass and profound hypothermia is removed. This approach restores aortic continuity without sacrifice of the major vessels, use of ductal tissue, or use of prosthetic grafts that will necessitate reoperation.

In vitro capacitation of goat spermatozoa

Goat epididymal and ejaculated spermatozoa were incubated in Krebs-Ringer bicarbonate buffer containing pyruvate and lactate as energy source. A 3 hr incubation for epididymal and 4 hr for ejaculated spermatozoa was required for the capacitation and acrosome reaction to take place. Calcium is an essential requirement which was needed for motility maintenance/activation and for the initiation of acrosome reaction. A 2-fold increase in cAMP content was measured over 3 hr period of incubation of goat epididymal spermatozoa which was not seen when calcium ions were either omitted or chelated with EGTA. There is thus a definite involvement of Ca2+ ions and cAMP in capacitation and acrosome reaction of goat spermatozoa.

Induction of a high-capacity nitrate-uptake mechanism in barley roots prompted by nitrate uptake through a constitutive low-capacity mechanism

Roots of nitrate-starved and nitrate-pretreated seedlings of Hordeum vulgare were used to investigate the induction of a high-capacity uptake mechanism for nitrate. When exposed to 0.2 mmol·l(-1)KNO3, nitrate-starved roots took up nitrate at a rate of approx. 1 μmol·(g FW)(-1)·h(-1); K(+) was absorbed at a rate ten-times higher. Nitrate uptake accelerated after a lag of about 1 h, until it matched the rate of K(+) uptake about 4 h later. p-Fluorophenylalanine (FPA), which prevents the synthesis of functioning proteins, suppressed the development of the high-capacity mechanism. Pretreatment of the roots with 0.2 mmol·l(-1) Ca(NO3)2 for 24 h established the high-capacity mechanism. Pretreated roots were able to absorb nitrate at high rates immediately upon exposure to 0.2 mmol·l(-1)KNO3, in the absence or presence of FPA. The high-capacity mechanism, once established, appeared to have a protein turnover as slow as that of the low-capacity mechanism or that of the mechanism involved in the uptake of K(+). In contrast, the mechanisms for the transport of nitrate and K(+) into the xylem vessels were completely blocked by FPA within 1 h of application, confirming earlier evidence for a rapid turnover of the transport proteins in the xylem parenchyma.Nitrate reduction proceeded at rates which were roughly one-tenth as large as the rates of the respective nitrate-uptake processes, indicating that nitrate-reductase activity was determined by the rate of nitrate uptake and not vice versa.We conclude that the formation of a high-capacity nitrate-uptake mechanism in barley roots occurs in response to nitrate uptake through a constitutive mechanism of low capacity which appears to function as a sensing mechanism for nitrate in the environment of the roots.

Close coupling between extrusion of H(+) and uptake of K (+) by barley roots

Extrusion of H(+) by intact barley (Hordeum vulgare L.) roots was automatically titrated. Simultaneously, uptake of K(+) into the roots, transport of K(+) through the roots, and (as a residual term) accumulation of K(+) within the root tissue were determined. When no monovalent cation was present in the medium the steady rate of H(+) release was close to zero. Addition of K(+) stimulated H(+) extrusion within less than 1 min. The stimulation of H(+) release was apparently limited only by the movement of K(+) through the apoplast of the roots. The steady rate of H(+) extrusion depended on the availability of external K(+) and saturated at a K(+) concentration of about 100 μmol· dm(-3). Half-maximum rates of net K(+) uptake and H(+) extrusion were reached at a K(+) concentration of about 10 μmol·dm(-3). With (slowly absorbable) sulfate as the only anion present, the stoichoimetry between H(+) release and net K(+) uptake was one. In conclusion, the uptake of K(+) across the plasmalemma of the cells of the root cortex is electrically coupled to H(+) extrusion.

Movement and compartmentation of abscisic acid in guard cells of Valerianella locusta: Effects of osmotic stress, external H(+)-concentration and fusicoccin

Epidermal peels of Valerianella locusta were acid-treated for 1 h at pH 3.9 to kill all cells other than guard cells. These guard-cell preparations were used to explore the steady-state one-way fluxes and the cytoplasmic and vacuolar contents of abscisic acid (ABA). The method of compartmental analysis has been applied. The intracellular ABA concentrations were surprisingly high. At an external pH of 5.8 the cytoplasm contained 1.28 mmol·dm(-3) of ABA, twice of the amount which accumulated in the vacuoles (0.57 mmol·dm(-3)). The fluxes of ABA at the plasmalemma (ϕoc=ϕoc=0.43 fmol · cell (-1) · h (-1)) were higher than those at the tonoplast (ϕcv=ϕvc=0.12 fmol · cell (-1) · h (-1)). Moderate stress (0.1 and 0.3 mol·dm(-3) sorbitol in the medium) caused a change in the kinetics of ABA movement. The rate constants of the fluxes from the cytoplasm into the vacuole (ϕcv) and into the apoplast (ϕco) were increased while the rate constant of the flux from the vacuoles into the cytoplasm (ϕvc) was decreased. As a consequence the amount of ABA sequestered in the vacuole remained unchanged; the cytoplasmic ABA content, however, was reduced to only 20% of that found in the control treatments (no sorbitol in the medium). Under moderate stress, one Valerianella guard cell released rapidly about 0.36 fmol·cell(-1) to its direct cell-wall space. This surprising result is discussed in regard to rapid stomatal closure under reduced water supply.

Effects of abscisic acid on sequestration and exchange of Na(+) by barley roots

Excised Na(+)-starved barley roots were suspended in solutions of Na(+) in combination with NO 3 (-) , Cl(-), and SO 4 (2-) , and effects of the added phytohormone, abscisic acid (ABA), to the medium were determined. Abscisic acid increased the rate of Na(+) ((22)Na(+)) accumulation and the amount of Na(+) deposited in the vacuoles. These stimulating effects of ABA were modified by anions following the sequence NO 3 (-) >Cl(-)>SO 4 (2-) . Testing whether the magnitude of the pH gradient across the plasmalemma of the cells of the root cortex affects rates of Na(+) accumulation and their dependence upon ABA, we observed that, in the pH range from 4 to 8, the ABA-induced stimulation was strongest at pH 5.8, and least at pH 4. Changes in pH during the experiment caused changes in the rates of Na(+) accumulation in agreement with experiments performed at constant pH values. Simultaneously with ABA-enhanced accumulation, loss of Na(+) occurred. Loss of Na(+) was strongest at pH 4 and was affected by anions, being greatest with SO 4 (2-) and following the sequence SO 4 (2-) >Cl(-)>NO 3 (-) . On the basis of the finding that initial acceleration of uptake as well as loss of Na(+) depended on the pH of the medium we suggest that, in barley roots, ABA stimulates an exchange of Na(+) for H(+) at the plasmalemma of the cortical cells. The results indicate that ABA-stimulated expulsion of Na(+), in combination with ABA-stimulated sequestration in the vacuoles, constitutes one of the mechanisms which enable barley plants to tolerate higher than normal levels of Na(+).

[Effect of light on transport of 2-[(14)C]abscisic acid through root segments of runner beans]

Light promotes the acropetal movement of 2-[(14)C]ABA through root segments of Phaseolus coccineus L. The promotion occurs only when the segments are irradited during the transport period. Red light and blue light are as effective as white light. There is no significant promotion when the segments are irradiated with green light or when they are kept in darkness during the transport period after preceding light treatment. Light has no effect on basipetal ABA-transport.

[Localisation of acropetal transport of 2-[(14)C]abscisic acid in roots of Phaseolus coccineus L. and evidence for a radial ABA-translocation between stele and cortex]

Acropetal polarity of ABA-transport in roots of runner beans is found to be located strictly in the stele. ABA movement in the cortex is very slow and unpolar. Experiments on partly decorticated and desteled roots gave evidence for a radial ABA-transport between the stele and cortex. Thus an ABA distribution quotient stele/cortex of 12/1 (expressed on tissue volume basis) is established after 9 h ABA incubation. The radial ABA-translocation is strongly inhibited at low temperature.

[Transport and metabolism of 2-[(14)C]abscisic acid in root segments of Phaseolus coccineus L]

Movement of 2-[(14)C]ABA through 1.5 cm and 5 cm long root segments of P. coccineus L. was acropetally polarised. The velocity of acropetal transport of [(14)C]ABA in 1.5 cm long segments was 4-5 mm·h(-1). Up to 11 h after the start of incubation [(14)C]ABA could be extracted unchanged. Beyond this time radioactivity became associated to an unidentified compound, which shows chromatographic qualities similar to those of Milborrow's "Metabolite C" (Biochemistry & Physiol. Plant Growth Substances, 1531, Runge Press Ottawa, 1968; and Chem. Comm. 966, 1969).