**2. Prokineticins and their receptors**

Prokineticins are anorexigenic and angiogenic hormones. Because of the structural, signaling and functional similarities, prokineticins are considered as cytokines/chemokines [5]. They are released principally by macrophages and reproductive organs [6]. Recently, prokineticin is considered as an adipokine because a high level of prokineticins has been found in obese human WAT [7]. These small peptides (80–120 amino acids) are called prokineticins, because these molecules were first identified as potent contractile factors in the gastrointestinal tract [8]. Two isoforms of prokineticins have been identified: prokineticin‐1 and prokineticin‐2. Prokineticin‐1 has been originally called as endocrine gland‐derived vascular endothelial growth factor (EG‐VEGF), [9] because of its functional similarity to VEGF. Prokineticin‐2 is also called as Bv8. Both of these peptides are 45% identical with highly conserved N‐terminal AVITGA motif essential for their biological activity [6, 10]. Prokineticin activity is mediated by two G‐protein‐coupled receptors, PKR1 and PKR2 [11].


**1. Introduction**

The dynamic changes in nutrition in terms of food quality and health safety requirements prompt the consumer to look for food produced in strictly defined systems, e.g., in the organic farming system [1,2]. This is confirmed by the continuous increase in the global organic food market [3–5] and the frequency of purchase of such products [6]. There is a common belief that organic food has higher nutritional values, is healthier and safer [7–10], and reduces the risk of overweight and obesity [11]. Recent literature reviews and metaanalyses have revealed significant differences in the nutritional composition of organic and conventional food [5,8]. Organic meat has better nutritional properties than industrially produced meat, which is reflected in a considerably improved composition of animal fats (higher concentrations of n-3 fatty acids), higher content of biologically active compounds, and lower cholesterol levels [1,12]. A higher frequency of consumption of organic meat in the diet can significantly reduce the prevalence of various lifestyle diseases [13].

Meat from game animals is a highly valued culinary and processing raw material due to its flavor, excellent nutritional properties, and high pH stability in the maturation process [14–16]. It can be classified as very lean meat [16–18]. Over the last few years, the interest in this meat has been increasing as it is regarded as "natural and sustainable" [19]. Wild-living animals experience a high standard of welfare and eat mainly natural food. Their meat is free of antibiotics and hormones [20]. Meat of various cervid species is also

**Citation:** Kilar, J.; Kasprzyk, A. Fatty Acids and Nutraceutical Properties of Lipids in Fallow Deer (*Dama dama*) Meat Produced in Organic and Conventional Farming Systems. *Foods* **2021**, *10*, 2290. https://doi.org/ 10.3390/foods10102290

Academic Editors: Benjamin W. B. Holman and Eric Nanthan Ponnampalam

Received: 6 August 2021 Accepted: 23 September 2021 Published: 27 September 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

produced on farms. In Poland, the red deer (*Cervus elaphus*), the sika deer (*Cervus nippon*), and especially the fallow deer (*Dama dama*) are reared quite commonly [21]. Compared with other cervid species, fallow deer meat is regarded as a healthier product due to the higher content of n-3 polyunsaturated fatty acids (PUFAs) [17]. It is high in protein, heme iron, copper, zinc, and potassium and low in saturated fatty acids [17,18,22–25]. The meat of cervids is also a good source of nutritionally important conjugated linoleic acid (CLA) [25]. Due to the essential role of fat in the human diet, the quantity and quality of lipids in meat from various animal species are the focus of considerable research interest [7,26–31].

The aim of the study was to evaluate the fatty acid profile and nutraceutical properties of lipids in fallow deer (*Dama dama*) meat produced in organic and conventional farming systems. Additionally, an attempt was made to estimate the nutritional contribution of this type of meat in the diet of adults in terms of the levels of total fat, fatty acids, and cholesterol.


*1.1.2 The Patient Cart*

This presents an adjustable support structure named boom which offers flexibility in positioning his arms over the surgical table. It has universal arms which allow the assignment and re-configuration of endoscope and instruments to desired ports during a surgical procedure.

The Helm touchpad allows non-sterile OR Staff to select the Patient Cart setting and adjust boon height or position for the best efficiency.


**Author details**

Eiman Mohammad Shahrour Faculty of Pharmacy, Department of Biochemistry and Microbiology, Ministry of High Education, Tishreen University, Lattakia, Syria

\*Address all correspondence to<EMAIL_ADDRESS>
© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


*3.5. Intermittent Structure Model*

In order to understand the peaks and valleys of turbulence intensity and high-order moments during the transition, an intermittent structure model is constructed as follows. For convenience, the characteristic velocity is chosen as 1.5*U*∗ *b* instead of *U*∗ *c* in this subsection. The velocity during the turbulent period is decomposed into two parts: the turbulent mean velocity, *UT*, representing the behavior of low-frequency and large-scale structures, and the turbulent perturbation velocity, *uT* (relative to *UT*), denoting the high-frequency and small-scale components. *U* = *UT* + *uT*, and it is assumed that *uT* satisfies Gaussian distribution, i.e., the time averaged values *uT* = 0, *u*3 *T* = 0, and *u*4 *T* = 3 *u*2 *T* 2 , but its temporal and spatial distribution is strongly asymmetric and aperiodic just like the measured velocity (gray curve) shown in Figure 9a. Assuming that *UT* and *u*2 *T* are the same for all localized turbulent patches in a given case and *FT* is known, it can be derived that the mean velocity *Uc* = *U*0 − *FT*(*U*0 − *UT*) and the fluctuation velocity relative to *Uc* is as follows:

$$
\mu = \mathcal{U} - \mathcal{U}\_c = \begin{cases}
\, \, \, \_T (\mathcal{U}\_0 - \mathcal{U}\_T)\_\prime & \text{laminar periods}, \\
\, \, (\mathcal{U}\_0 - \mathcal{U}\_T) (\mathcal{F}\_T - 1) + \mu\_T & \text{turbulent periods}.
\end{cases} \tag{1}
$$

**Figure 9.** (**a**) The simplified velocity signal (thick solid line) of the intermittent structure model at midplane, and the time averaged (**b**) *U*0 − *UT* and (**c**) *u*2 *T* sampled at the midplane during the turbulent periods. A measured midplane velocity signal is shown in (**a**) by the gray curve for a reference.

Consequently, the turbulence intensity and the high-order moments can be derived as follows:

$$\begin{cases} I\_{\rm u} = \frac{\sqrt{\{\mu^2\}}}{\mathcal{U}\_{\rm c}} = \frac{\sqrt{F\_T(1-F\_T)(\mathcal{U}\_0 - \mathcal{U}\_T)^2 + \{\mu\_T^2\}F\_T}}{\mathcal{U}\_0 - F\_T(\mathcal{U}\_0 - \mathcal{U}\_T)}\\ \{\mu^3\} = 3F\_T(\mathcal{U}\_0 - \mathcal{U}\_T) \{\mu\_T^2\}(F\_T - 1) - F\_T(\mathcal{U}\_0 - \mathcal{U}\_T)^3 \{2F\_T^2 - 3F\_T + 1\} \\ \{\mu^4\} = F\_T(1-F\_T) \left(1 - 3F\_T + 3F\_T^2\right) \left(\mathcal{U}\_0 - \mathcal{U}\_T\right)^4 + 3F\_T \{\mu\_T^2\}^2 + 6F\_T \{\mu\_T^2\}(F\_T - 1)^2 \left(\mathcal{U}\_0 - \mathcal{U}\_T\right)^2 \end{cases} \tag{2}$$

*UT* is estimated by the mean value of low-pass filtered midplane velocity during the turbulent periods at each *Re*, and the cutoff frequency, *fc*, used for the filtering is the same as those used for calculating *FT*. It is shown in Figure 9 that *U*0 − *UT* increases with *FT*, while the variance *u*2 *T* increases first then decreases with the growth of *FT*, reflecting the fact that the localized turbulent structures are influenced to some degree by the entrance disturbances, *FT*, and then *Re*. *U*0 − *UT* and *u*2 *T* may be fitted as follows:

$$
\Delta l\_0 - \mathcal{U}\_T = 0.06 \left( 1 + F\_T^4 \right)\_\prime \quad \left\langle u\_T^2 \right\rangle = 0.0026 + 0.01 \left( F\_T - 0.64 F\_T^7 \right)\_\prime \tag{3}
$$

which are shown in Figure 9b,c as solid curves.

According to the previous studies [42], the characteristics of localized turbulent bands, e.g., the band's tilt angle, width, and convection velocity, do not change much during the transition. Similar properties are shown in Figure 4d, as well: The midplane velocity defects of localized turbulent structures are similar and not very sensitive to the Reynolds number, the entrance disturbances, and the turbulence fractions. Therefore, these localized turbulent structures may be simplified to a unified structure, whose statistical dimensionless properties are independent of time, *FT*, and the initial or upstream disturbances. This unified structure is referred as turbulence unit hereafter. Consequently, *U*0 − *UT* and *u*2 *T* are chosen for mature structures and are set as the values when *FT* reaches 1, and then Equation (3) is simplified as follows:

$$\begin{aligned} lL0 - lL\tau &= 0.12, \quad \left\langle u\_T^2 \right\rangle = 0.006. \end{aligned} \tag{4}$$

For all three test cases, it is shown in Figure 10a–i by the solid lines that the main features of the second-, third-, and forth-order moments predicted by the model are consistent acceptably with the experimental results when the relations between *FT* and *Re* shown in Figure 8b are applied. The variance of the midplane streamwise velocity *u*2 is *FT*(1 − *FT*)(*U*0 − *UT*) 2 + *uT* 2 *FT*, where the contribution of fluctuations (the second term) increases with *FT*, while the first term increases first and then decreases with *FT* due to the fact that the mean velocity, *Uc*, leaves *U*0 for *UT*, leading to a peak value of *u*2 . Consequently, there exist peak values of *Iu* and *u*4 during the transition. Furthermore, when *FT* is close to 1 and the flow field is nearly fully occupied by the localized turbulent structures, *Uc* is almost as low as *UT*, and *u*2 and *u*3 are close to *uT* 2 and *uT* 3 , respectively. Therefore, at the

late transition stage, *u*3 should be close to zero again, and then there must exist a minimum *u*3 during the transition. Similarly, the asymptotic values for *Iu* and *u*4 should be finite ( *uT*2 /*UT* and 3 *uT* 2 2 in the model), just as shown by the experimental data in Figure 10. The consistencies of the model curves with the experimental data indicate that, not only the turbulence fraction, but also the characteristics of localized structures is required in order to describe properly the statistical properties of transitional flows.

**Figure 10.** Turbulence intensity (**a**–**c**), the third (**d**–**f**) and the fourth (**g**–**i**) order moments of the midplane velocity, and the friction coefficient (**j**–**l**) for different disturbance cases. The symbols of different cases shown in (**a**–**i**) are experimental data measured at (*x*, *y*, *z*) = (780, 0, 0), and *Cf* symbols shown in (**j**–**l**) are the same as those shown in Figure 3a. The solid curves are the results of the intermittent structure model.

Recently, it is found that, for a channel flow with constant pressure gradient, the kurtosis of the bulk velocity, which fluctuates during the transition and is represented by *Re*b in the simulations [34], increases abruptly as the Reynolds number decreases to the threshold value. However, the kurtosis obtained in experiments is close to zero near the onset of turbulence, as shown in

Figure 6. This discrepancy may be explained to some degree with the present model. Considering that, in simulations, the velocities in the laminar periods are as clean as the present model and have no background random noise, an inevitable factor in experiments, then when *FT* is close to 0, *u*4 ∼ *FT* while *u*2 2 ∼ *FT* 2 according to Equation (2), and hence the kurtosis will increase sharply.

Next, we use this model to study the dynamic property. Considering a turbulence unit with volume, *V*, mean velocity, *UT*(*y*), and mean pressure, *PT*, the perturbation velocities are *uT*, *vT*, and *wT*, and then the volume averaged friction coefficient is obtained from the mean x-momentum equation:

$$\mathcal{L}\_{fT} = -\frac{2}{V} \int \frac{\partial \mathcal{P}\_T}{\partial \mathbf{x}} \mathrm{d}\mathbf{V} = -\frac{2}{\mathrm{Re}V} \int \frac{d^2 \mathcal{U}\_T}{dy^2} \mathrm{d}\mathbf{V} + \frac{2}{V} \int \left[ \frac{\partial \left}{\partial \mathbf{x}} + \frac{\partial \left< \mu\_T \mathbf{u} \mathbf{r} \right>}{\partial \mathbf{z}} \right] \mathrm{d}\mathbf{V}.\tag{5}$$

Note that 1 −1 ∂*uTvT* ∂*y dy* = 0. Since the velocity fluctuations are strongly asymmetric and there is nearly a velocity discontinuity at the later edge of time series (upstream edge) of the structure and the present model (Figure 9a), the Reynolds stresses, e.g., *u*2 *T* , are different at the upstream and the downstream edges of the turbulence unit. In fact, the Reynolds stresses of a localized turbulent band are aperiodic in both the streamwise and the spanwise directions, as shown by the disturbance velocity structures in Figure 2b of Reference [23], due to its oblique manner. Since the transition occurs at relatively high Reynolds numbers and the properties of turbulence unit are assumed to be weak functions of *Re*, − 2 *ReV d*2*UT dy*2 dV may be expanded with 1/*Re* as 4 *Re* − 2 *Re*- *A*0 + *A*1 1 *Re* + *A*2 1 *Re*2 + ... , where 4 *Re* corresponds to the laminar state, and the constants *Ai* represent the contribution of mean flow modification. Similarly, the Reynolds stress term (the second term on the right hand side of Equation (5)) is expanded as *B*0 + *B*1 1 *Re* + *B*2 1 *Re*2 + ..., where the constants *Bi* reflect the aperiodicity of the Reynolds stress. Consequently, Equation (5) can be expressed as follows:

$$C\_{fT} = B\_0 + \frac{1}{Re}(4 - 2A\_0 + B\_1) + \frac{1}{Re^2}(B\_2 - 2A\_1) + \dots = B + \frac{A}{Re} + O\left(\frac{1}{Re^2}\right) \tag{6}$$

where *A* and *B* are constants for the turbulence unit. For a transitional flow with a turbulence fraction, *FT*, the total friction coefficient can be obtained as follows, after ignoring the higher orders terms in Equation (6):

$$C\_f = (1 - F\_T)\frac{4}{Re} + C\_{fT}F\_T = \left(1 - F\_T + \frac{A}{4}F\_T\right)\frac{4}{Re} + F\_TB. \tag{7}$$

It is shown in Figure 10j–l and that Equation (7) describes well the variations of *Cf* data for different entrance disturbance cases when the measured relation between *FT* and *Re* are applied. *A* and *B* are determined by fitting the data between *Re* = 1300 and 2000 as 0.78 and 0.00426, respectively.

At the initial and middle stages of transition, *Cf* may have different variation scenarios. If the external disturbances are not effective to trigger the turbulent patches and the transition starts at high Reynolds numbers, - 1 − *FT* + *A* 4 *FT* 4 *Re* may become smaller than *FTB* after a short *Re* range, and then there will be a stage where *Cf* increases with *FT* and *Re*, as shown in Figure 10. Note that *A* < 4 and - 1 − *FT* + *A* 4 *FT* 4 *Re* decreases with the increase of *FT* and *Re*. Consequently, there will be a maximum of *Cf* during the transition as illustrated by the present data shown in Figure 10l and the data of Patel and Head [6] shown in Figure 10k. If the transition begins at low Reynolds numbers, the variation of - 1 − *FT* + *A* 4 *FT* 4 *Re* may be comparable with that of *FTB*. Depending on the variation feature of *FT*, the stage of *Cf* growth may be short or even disappear, and a *Cf* plateau may appear, where *Cf* remains nearly constant in a finite range of *Re*. The *Cf* plateaus were observed in the previous numerical simulations [22,24,34] and are shown in Figure 10k for references. According to Equation (7), provided that the decrease of - 1 − *FT* + *A* 4 *FT* 4 *Re* is balanced by the rise of *FTB*, *Cf* will keep constant, though this constant value may be different for different entrance or initial disturbances, domain sizes, and computational periods. At the late stage of transition, *FT* tends to 1, and *Cf* is close to *A*/*Re* + *B* according to Equation (7) and then decreases with *Re*. The dashed lines in Figure 10j–l, *Re* = 2 *Cf* exp 0.41 8 9*Cf* − 2.4, represent the fully developed turbulence [22,37], where the Reynolds stresses are assumed to be uniform in the streamwise direction. According to the experiments, *FT* is close to 1 as *Re* > 1100, but *Cf* still deviates from the dashed line as *Re* < 1750, indicating a moderately developed turbulent state. By extrapolating *A*/*Re* + *B* to the laminar value 4/*Re*, as shown by the dot-dash line in Figure 10l, we get *Re* = 756, corresponding to an asymptotic threshold for the moderately developed turbulence.


Section 3 Biliary System

therapy with endoscopic band ligation: A randomized double-blind placebocontrolled trial. The American Journal of Gastroenterology. 2009;104(3):617-623

Digestive System - Recent Advances

[18] Escorsell A, Ruiz del Arbol L, Planas R, et al. Multicenter randomized controlled trial of terlipressin versus sclerotherapy in the treatment of acute variceal bleeding: The TEST study. Hepatology. 2000;32(3):471-476

[19] Feu F, Ruiz del Arbol L, Banares R,

[20] Lo GH, Chen WC, Wang HM, et al. Low-dose terlipressin plus banding ligation versus low-dose terlipressin alone in the prevention of very early rebleeding of oesophageal varices. Gut.

[21] Bhutta AQ, Garcia-Tsao G. The role of medical therapy for variceal bleeding. Gastrointestinal Endoscopy Clinics of North America. 2015;25(3):479-490

[22] Bruha R, Marecek Z, Prochazka V, et al. Double-blind randomized multicenter study comparing the efficacy and safety of 10-day to 5-day terlipressin treatment of bleeding esophageal varices. Hepato-

Gastroenterology. 2009;56(90):390-394

[23] Chang TT, Lee FY, Tsai YT, et al. A randomized controlled study of lowdose and high-dose terlipressin in the control of acute oesophageal variceal

Gastroenterology and Hepatology. 1991;

[24] Cavallin M, Piano S, Romano A, et al. Terlipressin given by continuous intravenous infusion versus intravenous boluses in the treatment of hepatorenal syndrome: A randomized controlled study. Hepatology. 2016;63(3):983-992

haemorrhage. Journal of

6(5):481-484

86

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1291-1299

2009;58(9):1275-1280

**89**

**Chapter 6**

**1. Introduction**

by gall stones.

history books.

and Background

*Sam Koruth and Sooraj Sankar*

most patients with symptomatic gallstones.

operative therapy of gallstone diseases.

Prologue: Biliary System - History

Cholecystectomy is one of the most common surgeries performed all around the world; over 600,000 people in the US undergo cholecystectomies each year. It is the treatment of choice for inflammation of the gallbladder (cholecystitis), pain and inflammation related to gall stones (calculus cholecystitis) and pancreatitis caused

Carl Johann August Langenbuch, a 27-year-old director of the Lazarus Hospital in Berlin, first practiced cholecystectomy on a cadaver, and then in the year 1882, he performed a cholecystectomy on a man who had suffered from gallstones for 16 years and cured his painful condition overnight. He was initially frustrated and disturbed that his patients continued to suffer after minor procedures to drain or clean the gallbladder, and then he became determined to give these patients a cure rather than temporary relief, and thus the first open cholecystectomy captured the

By 1897, over 100 cholecystectomies had been performed, and it turned out that the removal of the gallbladder not only would not take life but could in fact provide a pain-free future. Then in 1985, the modern era of cholecystectomies began when the surgeon Erich Mühe of Böblingen, Germany, did the first endoscopic cholecystectomy. Thereafter the pioneers in France and the US surgeons attached a CCD video camera to a laparoscope allowing the surgical team to view the operative field and perform with laparoscopic instruments. A French gynecologic surgeon performed a laparoscopic gallbladder removal in 1987. Soon after that in just 2 years, demand for the laparoscopic approach transformed surgical practice in the US and other countries and subsequently recognized laparoscopic cholecystectomies as the gold standard treatment for gallstone disease. The benefits of the laparoscopic approach were ultimately codified in the new National Institutes of Health (NIH) guidelines in 1992, and they stated that it provided a safe and effective treatment for

To date, it is documented that more than 80% of the cholecystectomies are done via laparoscopic approach. The advantages of laparoscopic over open surgeries are quite clear. These advantages include shorter length of hospital stay, very less operative pain, avoiding a big scar over the abdomen, earlier return of bowel function, improved cosmesis, earlier return to normal activities and overall decreased cost. The rates of cholecystectomies have increased subsequently with the introduction of laparoscopic procedures accompanied by evidence of lower clinical thresholds for


6.3 Surgical approach: Access

The first puncture is performed in the umbilical scar where a 10 mm trocar is placed to introduce the optic (Figure 4–black circle) and the patient is kept in dorsal decubitus. After exploration of the cavity, the patient is placed in Trendelenburg (Lloyd Davies) position and the surgeon inserts two 5 mm trocars (Figure 4–blue circles) and a fourth trocar for the first assistant. The second assistant stands between the patient's legs to manipulate the uterus after placement of the uterine manipulator (Figure 4–second assistant). With the surgical team members in these positions it is possible to perform ureterolysis, uretero-ureteral anastomosis and ureterovesical reimplantations on the right (Figure 4-A) or on the left (Figure 4-B).

#### Figure 4. Trocar sites. Position of surgeons for access to the right distal ureter (A) and for access to the left distal ureter (B).