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O RI G I N A L A RT I CL E

Early and late postoperative inflammatory and collagendeposition responses in three different meshes: an experimental

study in rats

C. G. Pereira-lucena • R. Artigiani Neto •

D. T. de Rezende • G. de J. Lopes-Filho •

D. Matos • M. M. Linhares

Received: 12 January 2013 / Accepted: 12 December 2013 / Published online: 27 December 2013

Springer-Verlag France 2013

Abstract

Purpose Although meshes reduce abdominal herniarecurrence, they increase the risk of inflammatory com-

plications. This study aimed to compare the early and late

postoperative inflammation and collagen deposition

responses induced by three meshes.

Methods Rats were allocated into three groups. In group

I, a polypropylene (PP) mesh was implanted in the

abdominal wall. In groups II and III, PP ? polyglactin

(PP ? PG) and PP ? titanium (PP ? TI) meshes were

employed, respectively. On the seventh (7th) postoperative

day, collagen deposition and inflammation were evaluated,

and immunohistochemistry was performed on abdominal

wall biopsies. These data were compared with those

obtained on the fortieth (40th) postoperative day in a pre-

vious study.

Results The early inflammatory responses were the same

in all groups. With time, it decreased in group I

( p = 0.047) and increased in group II ( p = 0.003). Group I

exhibited early elevated VEGF ( p\ 0.001), COX2

( p\ 0.001), and collagen ( p = 0.023) levels, and group II

exhibited the most severe inflammatory tissue response. On

the 40th postoperative day, the VEGF ( p\ 0.001) and

collagen ( p\ 0.005) were reduced as compared with the

7th postoperative day in all groups.Conclusions Belatedly, the inflammatory reaction

decreased in PP mesh group and increased in PP ? PG

mesh group. The PP mesh induced early great elevations in

VEGF, COX2 and collagen levels, whereas the PP ? PG

mesh caused severe tissue inflammation with small eleva-

tion in these levels. PP ? TI mesh induced inflammatory

response levels between the others. In conclusion, the

inflammatory response depends on the mesh density and

also the mesh material with clinical implications.

Keywords Hernia Mesh Inflammatory response

Collagen VEGF COX2.INFLAMMATORY

Introduction

Cytokines are synthesized by injured tissue to modulate the

inflammatory cascade during the initial phase of repair in the

abdominal wall [1]. Cytokines are fundamental to cell pro-

liferation, the extracellular matrix, and collagen synthesis [2].

Meshes were developed due to the high rate of recur-

rence after hernia surgery with primary sutures, and mesh

application in abdominal wall repairs has reduced the

recurrence indexes from over 50 % to approximately 10 %,

particularly in ventral hernias [3]. Although meshes are the

most commonly used biomaterials in medical practice,

with approximately 1.5 million implants used per year [4],

numerous questions remain about the host inflammatory

response induced by mesh implants [3–10]. Despite the

frequent use of mesh implants, there remains no consensus

regarding their classification and nomenclature [11].

Polypropylene (PP) is the most commonly material

used to manufacture meshes, but other absorbable and

C. G. Pereira-lucena R. Artigiani Neto

D. T. de Rezende G. de J. Lopes-Filho D. Matos

M. M. Linhares

Pós-Graduação em Ciência Cirúrgica Interdisciplinar,

Universidade Federal de São Paulo, Rua Napoleão de Barros,

610-Vila Clementino, São Paulo, SP CEP 04024-002, Brazil

C. G. Pereira-lucena (&)

Rua Volney Loureiro Tavares, No. 27-bairro Inácio Barbosa,

Aracaju, SE CEP 49040-670, Brazil

e-mail: [email protected]

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Hernia (2014) 18:563–570

DOI 10.1007/s10029-013-1206-4


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non-absorbable materials are also used [11, 12]. Theo-

retically, the increased diameter of the pores and the

reduction in the density of meshes could minimize

inflammation and, therefore, the complications related

to this implant [8]. However, several studies have

reported conflicting results, including reports of the

reduction of early complications and reports of a pos-

sible increase in recurrences [13–18]. Unexpectedcomplications, such as the reduced sperm mobility in

response to lightweight mesh implanted in the inguinal

region [17] and mechanical failure with fracture of a

lightweight mesh in the surgical repair of a recurrent

median ventral hernia [18], have been reported.

Klinge et al. [11] evaluated the indications for explant-

ing mesh implants in 1,000 cases. Infection was the main

reason for removing small pore PP meshes, which were

prevalent in the reviewed data. Hernia recurrence was the

main reason for explanting large-pore meshes [11].

Pascual et al. [19] observed that an intense inflammatory

reaction was related to the presence of absorbable material;additional characteristics include low expression of growth

factors, worse collagen deposition, and worse mesh inte-

gration in host tissue [19].

Some authors have studied mesh modified with a coat-

ing film or the use of various substances, including those

from hormonal sources, like aldosterone. Although these

authors shared the goals of reducing the formation of

adhesions or modulating the inflammatory process, e.g., the

action of mast cells, foreign body reactions, or fibrosis [12,

20–22], their results are varied.

In a previous study, we assessed the serum, inflam-

matory response, and collagen deposition in rats on the

40th postoperative day after mesh implantation, includ-

ing conventional PP, lightweight PP ? polyglactin

(PG ? PG), and lightweight PP ? titanium (PP ? TI).

Serum cytokines were similar in all groups. The heavy-

weight PP mesh belatedly induced the least inflammation

and improved collagen deposition. The PP ? PG mesh

was correlated with the most intense tissue inflammatory

response and low, irregular, and heterogeneous collagen

deposition. The PP ? TI mesh led to an intermediate

result [23].

The above results prompted further questions. The

results appear contradictory with respect to whether

collagen deposition depends on an inflammatory reac-

tion. PP mesh belatedly induces a subdued inflammatory

reaction but leads to greater collagen deposition, which

is in direct contrast with the results observed for the

PP ? PG mesh. Would it be possible to demonstrate a

more intense early tissue inflammatory response with PP

mesh? Could the kind of inflammatory reaction induced

by the PP ? PG mesh be the key factor for the belated

inhibition of collagen deposition? Could the differences

be due to pro-inflammatory molecules present in the

host tissue, especially growth factors related to collagen

deposition that were not detected in the blood of

animals?

This study aimed to compare the early (7th postopera-

tive day) and late (40th postoperative day) inflammatory

tissue response (histological changes and immunohisto-

chemistry for inflammatory substances) and collagenmorphology in response to conventional PP, lightweight

PP ? PG, and lightweight PP ? TI meshes.

Methods

This research was an experimental study in which it was

employed an acute wound model, not a hernia model.

Thirty male adult Wistar rats weighing 250–300 g were

randomly allocated into groups I, II and III. Each group

comprised 10 animals. An intraperitoneal injection of 10 %

ketamine hydrochloride and 2 % xylazine solution wasapplied for anesthesia.

After a 4-cm longitudinal incision was made along the

animal’s flank, a fragment of the anterior abdominal

musculature measuring 2 cm2 (2.0 9 1.0 cm) was

removed. The mesh was positioned to replace the defect

that had been produced and was fixed by six PP 3-0

switches sutures. In group I, the mesh was made of

heavyweight monofilament PP and had small pores (In-

tracorp, Venkuri, Brazil). In group II, the mesh contained

large pores and was made of lightweight PP and an

absorbable material, PG (VyproII, Ethicon, USA). In

group III, a large-pore lightweight mesh made of PP and a

nonabsorbable material, TI, was used (Timesh, GfE,

Germany).

Group I, the group in which the animals were implanted

with the most commonly used type of mesh [11], was

considered the control group.

On the 7th postoperative day, the rats were killed by

means of a lethal dose of ketamine. A fragment was

removed from the central region of the prosthesis as far as

possible from the mesh stitches. The tissue sample was sent

for a histological inflammatory response analysis, includ-

ing hematoxylin-eosin, Masson trichrome, and picrosirius

(under polarized light to assess collagen deposition), and

the immunohistochemical analysis of Vascular Endothelial

Growth Factor (VEGF-Dbs rabbit polyclonal antibody,

Santa Cruz Biotechnology, Inc.) and Cyclooxygenase 2

(COX2-rabbit polyclonal antibody, Spring Cold Spring

Harbor Laboratory, USA).

To objectively evaluate the tissue reaction and expres-

sion of VEGF and COX2, numeric scales were employed

[23–25], and the scoring scales are presented in Tables 1,

2.

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Pixels corresponding to collagen were counted on amicrocomputer after image capture using Image Tool

software, version 3.0, according to the following steps:

• gray scale conversion;

• automatic threshold;

• image inversion for better viewing;

• automatic collagen pixels count by the computer

program.

These data were compared with previously obtained

data from our group using the same methodology on the

40th postoperative day [23].

For the statistical analyses of the histological and

immunohistochemistry scores, the nonparametric Kruskal–

Wallis test was used. For the morphometric analysis of the

collagen and the inflammatory score, a sum ANOVA was

used. To compare early and late postoperative results, the

Mann–Whitney (tissue response, VEGF, and COX2) and

student’s t (tissue response score sum and collagen) tests

were employed. Statistical calculations were performedusing the Statistical Package for the Social Sciences

(SPSS) 19.0 for Windows, R-Program 2.11.1.

Results

In this research, we studied some aspects of the host

response resulting from the implantation of three different

meshes (PP, PP and PP ? PG ? TI) in the abdominal wall

on early (7th PO) and late postoperative period (40th PO).

The obtained results are described below:

• Tissue inflammatory response: The early sum score of

histologic inflammation was quantitatively similar in all

groups ( p = 0.509). But, compared with the 7th post-

operative day, the scores on the 40th postoperative day

were decreased in group I (PP) ( p = 0.047) and

increased in group II (PP ? PG) ( p = 0.003). In group

III (PP ? TI), the early and late inflammatory responses

were the same ( p = 0.341). The results of the analyses

and the inflammatory parameters are shown in Fig. 1.

• Immunohistochemical expression of pro-inflammatory

substances: Group I exhibited early elevated expression

ofVEGF( p\ 0.001) and COX2 ( p\0.001), and groupII exhibited the lowest levels. On the 40th postoperative

day, VEGF decreased ( p\ 0.001) in all groups, and

reductions in COX2 were observed only in group I

( p = 0.011). These data are presented in Figs. 2, 3 and 4.

• Collagen deposition: On the 7th postoperative day,

group I exhibited the best collagen deposition

( p = 0.023), while group II exhibited the worst. When

we compared the early and late samples, collagen

deposition decreased over time in all groups, but the

reduction was more intense and organized in group I.

Figures 5, 6 and 7 demonstrate this comparison.

Table 1 Numeric scales to value tissue inflammatory response in

groups I (PP), II (PP ? PG) and (PP ? TI)

Points Legend

A: Cell layers at the margins of the granulomas

1 1–4 layers

2 5–9 layers

3 10–30 layers4 [30 layers

B: Inflammatory reaction in the host tissue

1 Non-dense, mature fibrous tissue

2 Immature fibrous tissue with fibroblasts and little collagen

3 Dense granular tissue with fibroblasts and many

inflammatory cells

4 Mass of inflammatory cells with disorganized connective

tissue

C: Inflammatory response on the mesh surface

1 Fibroblasts without macrophages or foreign body cells

2 Isolated foci of macrophages or foreign body cells

3 One layer of macrophages and foreign body cells4 Multiple layers of macrophages and foreign body cells

D: Tissue maturation

1 Dense, mature interstitial tissue, similar to normal connective

or adipose tissue

2 Interstitial tissue with blood vessels, fibroblasts, and a few

macrophages

3 Interstitial tissue with giant inflammatory cells but with

permeating connective tissue

4 Mass of inflammatory cells without permeating connective

tissue

Table 2 Numeric scales to value VEGF and COX2 imunohistochemistry expression in groups I (PP), II (PP ? PG) and (PP ? TI)

VEGF COX2

% cells Score Intensity Score % cells Score Intensity Score

0–25 1 Weak 1 0–25 1 Weak 1

26–50 2 Moderate 2 26–50 2 Moderate 2

51–75 3 Strong 3 51–100 3 Strong 3

76–100 4

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Discussion

The main reason for the subject and the design of this

research was our need to continue investigating the ques-

tions raised in our previous study, in which conventional

PP mesh placement unexpectedly and belatedly resulted in

less tissue inflammation and increased late collagen depo-

sition compared with PP ? PG and PP ? TI meshes.

The first phase of the healing process of the abdominal

wall (hemostasis ? inflammation) is indispensable for the

deposition of collagen and scar formation [2]. We won-

dered whether an early intense reaction, with the release of

pro-inflammatory cytokines, particularly growth factors,

could result in later collagen deposition resulting from PP

mesh.

We were also interested in exploring the effects of mesh

coated with an absorbable material on maintaining a for-

eign body-type inflammation, with granulomas formation

and reduced growth factors expression, potentially resulted

in less collagen deposition. Thus, we asked whether thepore size, mesh density, or type of material affected the

intensity and characteristics of the inflammatory response.

Previous research demonstrated that PP can induce a fast

inflammatory reaction, especially in the early phase after

surgery [26]. Some authors have noted that PP mesh causes

an elevated short-term inflammatory reaction, resulting in

more discomfort for patients. However, in the long term,

various kinds of meshes exhibit similar behavior, and

higher rates of hernia recurrence have been reported with

lightweight mesh [6, 9, 11, 13, 14, 27]. Other studies,

however, have reported no differences in the inflammatory

response between various materials and have reported that

the mesh density is the most important factor affecting the

inflammatory response [5–8]. These diverse results could

be explained by the heterogeneity in the study designs and

the parameters studied.

In this research study, the results of the histological

analysis of inflammatory process were similar between the

groups on the 7th postoperative day. However, when we

compared the early and late postoperative periods, we

observed that, although there was no accentuation of the

Fig. 1 Boxplot graph that demonstrates the sum

(S = A ? B ? C ? D) of the items related to inflammatory tissue

reaction on 7th and 40th postoperative days (PO) in groups I, II and

III, where A is the layer of cells on granulomas, B is the inflammatoryreaction in host tissue, C is the inflammatory response on the surface

of the mesh, D is the tissue maturation

Fig. 2 Boxplot graph that demonstrates VEGF imunohistochemistry

expression on 7th and 40th postoperative days (PO) in groups I (PP),

II (PP ? PG) and III (PP ? TI)

Fig. 3 Boxplot graph that demonstrates COX2 imunohistochemistry

expression on 7th and 40th postoperative days (PO) in groups I (PP),

II (PP ? PG) and III (PP ? TI)

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inflammatory response over time in group III (PP ? TI), a

significant increase in the inflammatory response was

observed belatedly in group II (PP ? PG) ( p = 0.003), as

shown in Figs. 1, 2, 3. These results suggest that the

absorbable material may be the key determinant in the

intensity of the inflammatory process in meshes made of

PG, similar to the results of Pascual et al. [19]. However,

the late inflammatory response in group I (PP) was smaller

than the early response ( p = 0.047), supporting the idea

that this material induced a rapid inflammatory reaction.

VEGF expression has been used previously to evaluate

the healing process after abdominal wall hernia surgery.

Some authors have reported increased expression of this

cytokine in response to PP meshes and lower expression in

response to meshes containing biodegradable material(e.g., PG) [19]. Our results corroborate the findings

described above. In group I (PP), the average VEGF

immunohistochemistry score was elevated on the 7th

postoperative day with respect to the other groups

( p\ 0.001), and all animals in this group, except one,

exhibited the maximum assessment scores. Group III

(PP ? TI) exhibited intermediate scores, whereas group II

(PP ? PG) exhibited the lowest scores.

With respect to the late inflammatory response, all

groups exhibited reductions in the late VEGF score com-

pared with the earlier score. These results are compatible

with the results obtained by Di Vita et al. [26] in their studyof serum VEGF levels in humans. The authors observed

higher cytokine levels during the early postoperative period

in patients undergoing surgical repair of hernias of the

abdominal wall, which could explain the rapidity of the PP-

receiving host response. We believe that new researches

could clarify this response and other questions, including

the COX2 involvement in the tissue inflammatory response

caused by mesh use and abdominal wall healing.

Fig. 4 Photomicrography (9100). Immunohistochemical analysis of COX2 (narrows) in groups I (PP), II (PP ? PG) and III (PP ? TI) on the

7th postoperative day. Observe mesh filaments (stars)

Fig. 5 Boxplot graph that demonstrates the score of the collagen

representative pixels on 7th and 40th postoperative days (PO) on

groups I (PP), II (PP ? PG) and III (PP ? TI)

Fig. 6 Photomicrgraphy (940). Picrosirius demonstrates collagen deposition (narrows) on the 7th postoperative day in groups I (PP), II

(PP ? PG) and III (PP ? TI). Observe mesh filaments (stars)

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Conflicting findings about collagen deposition in mesh

implants have been reported. Although some authors state

that there is increased collagen deposition in heavyweight

meshes, others claim the opposite [11, 26]. A recentlypublished study reports that PP meshes can result in a

higher density of collagen in the host scar tissue [ 28]. In the

current study, collagen reduction was observed in all

groups when we compared the evolution of the morphology

of collagen between the 7th and the 40th postoperative

days. However, on the 40th postoperative day, the collagen

deposition remained more intense and more organized in

response to PP mesh than for the other meshes (Fig. 6).

This amendment is consistent with some authors’

descriptions [2]. Vaz et al. [29] studied collagen deposition

in Wistar rats after PP mesh implantation. The authors’

results demonstrated that, on the 30th postoperative day,type III collagen (immature) was replaced by type I col-

lagen (mature) [2, 29]. Thus, in this study, we chose the

40th postoperative day as the endpoint of the late evalua-

tion. Moreover, 40 days in a rat’s life correspond to 3 years

and 3 months in humans, which is sufficient time for the

scar remodeling process [30]. This experimental design

minimizes the differences between the host response after

mesh implantation in rats and humans but cannot avoid

them completely. To evaluate tissue inflammation induced

by mesh implants over time, serial biopsies of the

abdominal wall would be necessary, which would be eth-

ically unacceptable. After experimental studies in animals,

new studies in humans could use other methods to analyze

abdominal wall healing, including computer tomography or

magnetic resonance.

Group II, which was characterized in the histological

studies by an intense inflammatory process, exhibited poorexpression of VEGF, which is a well-established important

inflammatory marker; this observation reinforces the

hypothesis that each mesh type induces a different reaction.

The observation that the mesh that induced lower VEGF

expression also induced less collagen deposition strength-

ens the probable relationship between this growth factor

and collagen. Our results strengthen the conclusions of

Pascual et al. [6], who reported that a material that stim-

ulates a foreign body-type reaction would, with the mini-

mal release of VEGF, result in a frail and disabled scar in

terms of collagen deposition. Further studies may shed

light on this topic.To synthesize the basic characteristics exhibited by the

mesh studied in this research, we have observed the

following:

• The conventional mesh, made of heavyweight PP with

small pores, exhibited an intense initial tissue inflam-

matory reaction, strong expression of VEGF and

COX2, and increased collagen deposition. Over time,

there was a reduction in the inflammatory response, the

levels of VEGF and COX2, expression, and collagen

deposition. On the 40th postoperative day, collagen

fibers were grouped into organized bundles, and thismesh exhibited the greatest collagen deposition among

the meshes studied.

• The lightweight mesh made of large pores consisting of

PP ? PG exhibited an intense initial inflammatory

reaction, predominantly of the foreign body type, with

the presence of abundant granulomas and giant cells.

Characteristically, faint VEGF and COX2 expression

and an erratic deposition of collagen were observed.

This reaction can be perpetuated, becomes even more

pronounced over time, and is likely related to the

presence of an absorbable material in the implant.

• The large pores and lightweight mesh made of PP andcovered with TI resulted in an intermediate histolog-

ically defined inflammatory response, intermediate

VEGF and COX2 expression, and intermediate colla-

gen deposition with respect to the other groups.

Although this mesh contains a an inert material that

is used in orthopedic and endovascular prosthesis, it led

to an early inflammatory reaction similar to other

meshes and long-term inflammation that was more

severe than that induced by the PP mesh.

Fig. 7 Photomicrography (9400): Picrosirius demonstrates collagen

deposition (arrows) on 7th and 40th postoperative days (PO) in

groups I (PP), II (PP ? PG) and III (PP ? TI). Note the organized

collagen deposition in group I and irregular collagen deposition in

group II

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Therefore, we conclude the following:

• Although the early inflammatory response was the

same in all groups, the late inflammatory response was

elevated in the PP ? PG mesh group and decreased in

the PP mesh group.

• On the 7th postoperative day, the greatest COX2

expression occurred in PP mesh. However, on the 40thpostoperative day, it decreased in the PP mesh group

but not in the PP ? PG and PP ? TI mesh groups.

• The mesh that resulted in the highest early VEGF

expression (PP) resulted in better collagen deposition,

whereas the mesh that resulted in the lowest VEGF

expression (PP ? PG) resulted in the worse collagen

deposition.

• The mesh density, pore diameter, and material can

influence the host inflammatory response resulting from

its implantation in the abdominal wall, with clinical

implications for wall rigidity, foreign body reaction,

abscesses, and infection.

Acknowledgments This research was funded by Fundação de

Amparo à Pesquisa do Estado de São Paulo (FAPESP) and the Co-

ordenação de Aperfeiçoamento de Pessoal de Nı́vel Superior

(CAPES).

Conflict of interest The authors declare no conflict of interest.

References

1. Dubay DA, Wang X, Kuhn A, Robson MC, Franz MG (2004)

The prevention of Incisional hernia formation using a delayed-

release polymer of basic fibroblast growth factor. Ann Surg

240:179–186

2. Whitte MB, Barbul A (1997) General principles of wound heal-

ing. Surg Clin N Am 77:509–528

3. Dubay DA, Wang X, Adamson B, Kuzon WM Jr, Dennis RG, Franz

MG (2006) Mesh incisional herniorrhaphy increses abdominal wall

elastic properties: a mechanism for decreased hernia recurrences in

comparinson with suture repair. Surg 140:14–24

4. Weyhe D, Belyaev O, Muller C, Meurer K, Bauer K, Papapstolou

G, Uhl W (2007) Improving outcomes in hernia repair by the use

of the light meshes: a comparison of different implant construc-

tions based on a critical appraisal of the literature. World J Surg

31:234–244

5. Asarias JR, Nguyen PT, Jr Mings, Gerrich AP, Pierce LM (2001)

Influence of mesh materials on the expression of mediatorsinvolved in wound healing. Invest Surg 24:87–98

6. Pascual G, Hernández-Gascón B, Rodrı́guez M, Sotomayor S,

Peña E, Calvo B, Bellón JM (2012) The long-term behavior of

lightweight and heavyweight meshes used to repair abdominal

wall defects is determined by host tissue repair process provoked

by the mesh. Surgery 152(5):886–895

7. Orestein SB, Saberski ER, Kreutzer DL, Novitski YW (2012)

Comparative analysis of histopathologic effects of synthetic

meshes based on material, weight and pore size in mice. J Surg

Res 176:423–429

8. Laschke MW, Hãufel JM, Scheuer C, Menger MD (2009)

Angiogenic and inflammatory host response to surgical meshes of

different mesh architecture and polymer composition. J Biomed

Res B Appl Biomater 91:497–507

9. Bellón JM, Rodrı́guez M, Garcı́a-Honduvilla N, Gómez-gil V,

Pascual G, Buján J (2009) Comparing the behavior of different

polypropylene meshes (heavy and lightweight) in an experi-

mental model of ventral hernia repair. J Biomed Mater Res B

Appl Biomater 89:448–455

10. Pascual G, Rodrı́guez M, Góez-Gil V, Garcı́a-Honduvilla N,

Buján J, Bellón JM (2008) Early tissue incorporation and colla-

gen deposition in lightweight polypropylene meshes: bioassay in

an experimental model of ventral hernia. Surgery 144:427–435

11. Klinge U, Klosterhalfen B (2012) Modified classification of

surgical meshes for hernia repair based on the analyses of 1,000

explanted meshes. Hernia 16:251–258

12. Regis S, Jassal M, Mukherjee N, Bayon Y, Scaborough N,

Bhowmick S (2012) Altering surface characteristics of polypro-

pylene mesh via sodium hydroxide treatment. J Biomed Mater

Res A 100:1160–1167

13. Gao M, Han J, Tian J, Yang K (2010) Vypro II mesh for inguinal

hernia repair: a meta-analysis of randomized controlled trials.

Ann Surg 251:838–842

14. Ladurner R, Chlapponi C, Linhuber Q, Mussack T (2011) Long

term outcome and quality of life after open incisional hernia

repair: light versus heavy weight meshes. BMC Surg 14:11–25

15. Smietański M, Smietańska IA, Modrzejewski A, Simons MP,

Aufenacker TJ (2012) Systematic review and meta-analysis on

heavy and lightweight polypropylene mesh in Lichtenstein

inguinal hernioplasty. Hernia 16:519–528

16. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW (2008) Open

surgical procedures for incisional hernias. Cochrane Database

Syst Rev 3:CD006438

17. Peeters E, Spissens C, Oyen R, De wever L, Vanderscheueren D,

Pennickx F, Miserez M (2010) Laparoscopic inguinal hernia

repair in men with lightweight meshes may significantly impair

sperm motility: a randomizes control trial. Ann Surg 252:

240–246

18. Lintin La, KIngsnorth NA (2012). Mechanical failure of a

lightweight polypropylene mesh. Hernia [Epub ahead of print]

19. Pascual G, Rodrigues M, Soromayor S, Pérez-Köhler B, Bellón

JM (2012) Inflammatory reaction and neotissue maturation in the

early host tissue incorporation of polypropylene prostheses.

Hernia 16(6):697–707

20. Altınel Y, Oztürk E, Ozkaya G, Akyıldız EU, Ulcay Y, Ozgüç H

(2012) The effect of a chitosan coating on the adhesive potential

and tensile strength of polypropylene meshes. Hernia 16(6):

709–714

21. Schug-Pass C, Sommerer F, Tannapfel A, Lippert H, Köckerling

F (2008) Does the additional application of a polylactide film

(SurgiWrap) to a lightweight mesh (TiMesh) reduce adhesions

after laparoscopic intraperitoneal implantation procedures?

Experimental results obtained with the laparoscopic porcine

model. Surg Endosc 22:2433–2439

22. Orenstein SB, Saberski ER, Klueh U, Kreutzer DL, Novitsky YW

(2010) Effects of mast cells modulation on early host response toimplanted synthetic meshes. Hernia 14:511–516

23. Pereira-Lucena CG, Artigiani Neto R, Frazão CVG, Goldenberg

A, Lopes-Filho GJ, Matos D, Linhares MM (2010) Experimental

study comparing meshes made of polypropylene, polypropyl-

ene ? polyglactin and polypropylene ? titanium: inflammatory

cytokines, histological changes and morphometric analysis of

collagen. Hernia 14:299–304

24. Madhusudan A, Asha J, Gayathri R, Rashmi M (2012) Expres-

sion of vascular endothelial growth factor and microvessel den-

sity in oral tumorigenesis. J Oral Maxillofac Pathol 16:22–26

25. Wang D, DuBois RN (2010) The role of COX-2 in intestinal

inflammation and colorectal cancer. Oncogene 29:781–788

Hernia (2014) 18:563–570 569

1 3


8/9

26. Di Vita G, D0Agostinho P, Patti R, Arcara, Caruso G, Davi,

Cillari E (2005) Acute inflammatory response after inguinal and

incisional hernia repair with implatation of polypropylene mesh

of different size. Langenbeecks Arch Surg 390:306–311

27. Brittner R, Schmedt CG, Leibi BJ, Schwartz J (2011) Early

postoperative and 1 year results of a randomized controlled trial

comparing the impact of extralight titanized polypropylene mesh

and traditional heavyweight polypropylene mesh on pain and

seroma production in laparoscopic hernia repair (TAPP). World J

Surg 35:1791–1797

28. Baktir A, Dogru O, Girgin M, Aygen E, Kanat BH, Dabak DO,

Kuloglu T (2012) The effects of different prosthetic materials on

the formation of collagen types in incisional hernia. Hernia

17(2):249–253

29. Vaz M, Krebs RK, Trindade EN, Trindade MR (2009) Fibro-

plasia after polypropylene mesh implantation for abdominal wall

hernia repair in rats. Acta Cir Bras 24:19–25

30. Quinn R (2005) Comparing rat’s to human’s age: How old is my

rat in people years? Nutrition 21:775–777 Editorial opinion

570 Hernia (2014) 18:563–570

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9/9

C o p y r i g h t o f H e r n i a i s t h e p r o p e r t y o f S p r i n g e r S c i e n c e & B u s i n e s s M e d i a B . V . a n d i t s

c o n t e n t m a y n o t b e c o p i e d o r e m a i l e d t o m u l t i p l e s i t e s o r p o s t e d t o a l i s t s e r v w i t h o u t t h e

c o p y r i g h t h o l d e r ' s e x p r e s s w r i t t e n p e r m i s s i o n . H o w e v e r , u s e r s m a y p r i n t , d o w n l o a d , o r e m a i l

a r t i c l e s f o r i n d i v i d u a l u s e .

early and late postoperative inflammatory and collagen

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