Types Of Branching Patterns Research Articles

Portal Vein Variations, Clinical Correlation, and Embryological Explanation: A Review Article.

Portal vein(PV) is a large vein that collects blood from the abdominal part of gall bladder, pancreas, alimentary tract, and spleen and transports to the liver. One of the parts of the extraembryonic venous system, the vitelline veins, is where PV starts.In about five weeks of gestation, a venous plexus is formed, and variations in this plexus lead to portal variance.Thejunction of superior mesenteric and splenic veins is typically where the vein begins to network. There are five types of branching patterns of the right PV: conventional branching, trifurcation branching, early branching, separate segment 7 branching, and separate segment 6 branching.To perform pancreatic, duodenal, and liver surgeries, knowledge of variations in PV formation is important.For surgical and interventional operations to be accurate, it is crucial to understand the architecture of the PV and its anomalies. As distinct regions of the brain connect with one another, portal architecture is frequently observed in imaging investigations. Portal hypertension is characterized as an increase in blood pressure in the portal venous system (PVS) in the context of severe liver disease, such as cirrhosis. Non-invasive methods for examining the anatomy and anomalies of the PV include ultrasound, computed tomography (CT), and magnetic resonance (MR). There are many abnormalities of PVS that have been discussed in the articles such as Congenital PV Absence; PV Branches Congenitally Grow in Structure; Hypoplasia, Atresia, and Stenosis of the PV; and Portosystemic Shunts.

Surgeon's role in CT-based preoperative determination of inferior mesenteric artery anatomy in colorectal cancer treatment

The inferior mesenteric artery (IMA) is a blood vessel of great importance in left colon and rectal cancer surgery. We aimed to determine the role of surgeons in computed tomography (CT) based vascular anatomy interpretation. Patients with left colon and rectal cancer treated surgically with D3 lymph node dissection and selective vascular ligation were included in this study. All patients (n=250) underwent preoperative CT with intravenous contrast. The IMA anatomy was schematically depicted by surgeon based on CT interpretation. Intraoperatively anatomy was defined by skeletonisation of the IMA. All patients had segmental resection with selective vascular ligation. The concurrence of prospectively obtained results were evaluated by intraclass correlation and Kendall's tau-b test. Misinterpretation of IMA anatomy was analysed by CT-specialist. The preoperative and intraoperative IMA anatomy features were correctly interpreted in 237 cases (in 94.8%) within skeletonisation extent, which is supported by high level of agreement and concordance of preoperative data regards to intraoperative findings (K=0.926; p<0.001; CC=0.912; p<0.001). As a result of the CT-based evaluation of the IMA, E, K, and H types of branching patterns were proposed. IMV position was mistakenly identified in 2.6% of cases. Surgeons are able to evaluate the IMA anatomy accurately with CT and use it in routine preoperative planning. The E, K, and H branching types may be used when defining approach to skeletonisation and level of vascular ligation.

Influence of Placental Metalloproteinase-9 Protein on the Branching Architecture of Chorionic Blood Vessels of Human Placenta

Introduction: In human placenta, two different branching patterns of chorionic blood vessels exist. In the dispersal type, the chorionic blood vessels undergo successive divisions with gradually diminishing caliber as the blood vessels traverse towards the placental margins. In the magistral type, the blood vessels traverse without appreciable decrease in diameter. We hypothesize, that matrix-degrading enzymes secreted by cytotrophoblasts may influence the branching patterns of these chorionic blood vessels. We, therefore, determined if placental expression of matrix metalloproteinase-9 (MMP-9) protein differed between the two vascular patterns of chorionic blood vessels of human placenta. Methods: 26 full-term delivered placentas were collected from normotensive women. Chorionic villi (CV) were isolated. CV MMP-9 protein was analyzed using human MMP-9 monoclonal antibody based ELISA kits. A novel method was used to determine the vascular patterns of the placentas from placental photographs. Independent t test was used for statistical analysis. P&lt; 0.05 was considered significant. Results: The branching pattern of the chorionic blood vessels was 54% dispersal and 46% of the magistral types. In placentas with dispersal type of branching pattern, MMP-9 protein expression was significantly higher (p=0.035). Women who delivered placentas with magistral type of branching pattern, the mean newborn weight was found to be significantly higher (p=0.039). Conclusion: The study introduces a novel method to investigate chorionic vascular network of human placenta. Our findings underscore the importance of CV MMP-9 protein in affecting the placental branching architecture of chorionic blood vessels in humans. In the magistral type, the calibers of the chorionic blood vessels from the point of insertion of the umbilical cord to the placental margins remained more or less unchanged. We suggest, that this unchanged caliber of blood vessels in the magistral type, may have allowed better nourishment and oxygen to be catered to the fetus; resulting in fetal weight gain.

A Study on Variation of Origin of Gastroduodenal Artery

Aim: The aim of the study is to note the variation in the origin of Gastroduodenal artery (GDA).&#x0D; In a study done on 30 cadavers at Seth G.S. Medical College and K.E.M. Hospital, Mumbai, India, during the period 2011–2012, it was found that there was a rare type of branching pattern of the gastroduodenal artery (GDA). The knowledge of variations is very important during the operative, diagnostic and endovascular procedures. Variations in the branching pattern of the cystic artery often occur and may be encountered during cholecystectomy or laparoscopic cholecystectomy and hepatobiliary surgeries. This study describes unusual origin of cystic artery from the gastro duodenal artery as found during routine dissection in a cadaver. The embryological development and clinical importance of such a variation have been emphasized.

A study of the anatomical variations in branching pattern of middle cerebral artery

Middle cerebral artery (MCA) is the largest and most complex arterial system of the brain. Variations of the aortic arch branches are due to alteration in the development of specific branchial arch arteries during the embryonic period. Knowledge of these variations is important during aortic instrumentation, thoracic, and neck surgeries. The anatomy of the anterior cerebral artery branches and the anterior communicating artery complex needs to be investigated individually to minimise neurovascular morbidity before iatrogenic procedures. The study aimed to study the variations in the microsurgical anatomy of the MCA in our population and compare the variables and discuss their importance with anatomic and surgical considerations. Specimens were collected from the embalmed cadavers and the post-mortem bodies in the department of forensic medicine of Thanjavur Medical College. The different variables regarding the MCA in our population were analysed and compared with the studies in the Western population and other Indian studies. The mean length of the MCA in this study was 12.8 mm with a standard error of 3.79 mm. The outer diameter of the M1 segment was with a mean length of 3.75mm. In 69.2% middle, Cerebral Artery shows bifurcation and in 20%, it shows trifurcation and in 10.8%, it shows ramification types of branching patterns. The 39.1% cases show Temporo polar, 21.7% orbitofrontal, 9.1% anterior temporal, 6.6% prefrontal, and 4.1% middle temporal branches. Our results also reveal that the origin of the lenticulostriate branch in the middle cerebral artery was 85.85% from the trunk and 14.2% from division, respectively. MCA branching pattern is slightly higher in trifurcation pattern as compared to bifurcation and ramification. Thorough knowledge of the microvascular anatomy and the myriads of variations is essential for the operating surgeon to choose the ideal technique to avoid any catastrophe during and after surgery and give the best possible functional outcome.

Study on branching pattern of segmental branches of splenic artery in human cadaveric spleens by dissection method

Spleen is the largest lymphoid organ. It is supplied by splenic artery the largest branch of coeliac trunk. It traverses through the lienorenal ligament to reach near the hilum of the spleen, where it divides into two or three primary branches, each of which is subdivided mostly into two or four secondary branches. Moreover, a superior polar arteries and inferior polar arteries are given from splenic trunk or from one of its primary branches, which goes to the poles of the spleen, without entering the hilum. It can be named as superior and inferior polar artery. The human spleen is divided accordingly into two or three main segments. The segments of spleen are separated by a definite avascular plane. Hence the partial removal of the spleen is possible, as the spleen is divided into segments, separated by fibrous septa and each segment is supplied by its own main artery. The present study was undertaken to study in detail the segmental branches of splenic artery which divide the spleen into various segments, its pattern of distribution and also to find out any inter-segmental arterial anastomosis by dissection method.1.To study segmental branches of splenic artery. 2. To study the anastomosis between the segmental branches. 3. To study the branching pattern of terminal division of splenic artery.The present study was conducted on 79 adult human cadaver spleens by dissection method, irrespective of their age and sex, fixed in 10% formalin solution, collected from the Department of Anatomy and Forensic Medicine, Mysore Medical College and Research Institute, Mysore. 1. Two primary segmental branches were seen in 56 (70.9%) specimens, three primary segmental branches were seen in 19 (24.1%) specimens and four primary segmental branches were seen in 4 (5.1%) specimens. 2. Superior polar artery was present in 18 (22.8%) specimens and inferior polar artery was present in 32 (40.5%) and both superior and inferior polar artery was seen in 5 (6.3%) specimens. 3. Anastomosis between the primary segmental branches were seen in 11(13.9%) specimens. 4. The distributive type of branching pattern of terminal division of splenic artery was present in 50 (63.3%) specimens, and the marginal type of branching pattern was present in 29 (36.7%) specimens.The present study adds up to the existing knowledge regarding the segmental branches of splenic artery, the better anatomical knowledge about segmental distribution of splenic artery and its variations are important for the partial removal of the spleen.

Quadrifurcation of Coeliac Trunk- A Case Report

During routine dissection of a cadaver in the department of anatomy at Seth GS Medical College and KEMHospital, we discovered a very rare type of branching pattern of the Coeliac Trunk (CT). The CT measured3cm in length and was quadrifurcating into replaced right hepatic artery, common hepatic artery, left gastricartery and splenic artery. The replaced right hepatic artery had unusual course where it ran behind theportal vein and bile duct to reach the right lobe of liver. Common hepatic artery after giving gastroduodenaland right gastric artery continued as middle hepatic artery while left hepatic artery originated from leftgastric artery. A complete knowledge of these variations are helpful for hepatobiliary surgeons and also forradiologists.

Anatomical Variations in the Origin of the Lingual Artery in the Kenyan Population.

Descriptive cross-sectional study. To determine the variations in origin of the LA and its relationship to surgical landmarks. The Lingual artery (LA) is a branch of the External Carotid Artery (ECA) that constitutes the principal supply to structures within the oral cavity and floor of the mouth. Knowledge of its variant anatomy is therefore vital during radiological and surgical procedures performed in the head and neck region since they may predispose it and other branches of the ECA to iatrogenic injury. There is, however, a dearth of regional data on the same. A total of 70 LA dissections were performed bilaterally on 35 human cadavers. The borders of the carotid triangle were identified after which the external carotid artery and its branches were exposed. The pattern of origin and the diameter of the LA was noted and distances from its origin to the CB, GCHB and the HN were measured. Similar measurements were carried out for any variant trunks. Data was collected and analyzed using SPSS (IBM version 27). A paired t-test was used to compare side differences. Representative photos of the vessel and its variations were taken. The LA was found to be present in all cadavers dissected and was bilaterally symmetrical in 43% of cases. Four (4) types of branching patterns were encountered in the present study, the most commonly observed being the solitary LA followed by the LFT, TLT and finally the TLFT. The average diameter was least in the solitary pattern and greatest in the TLT. In relation to the CB, the solitary LA originated at a distance of 1.51 ± 0.89 cm while the LFT, TLT and TLFT originated at a distance of 1.80 ± 0.73 cm, 1.02 ± 0.64 cm and 1.25 ± 0.01 cm respectively from the CB. The mean distance from the origin of the LA to the GCHB was least in the TLT and greatest in the TLFT. With reference to the hypoglossal nerve, the LA was at an average, 0.82 ± 0.15 cm from the HN for the solitary pattern, 1.34 ± 0.86 cm for the LFT, 1.34 ± 0.90 cm for the TLT and 1.38 ± 0.93 cm for the TLFT. The LA in the Kenyan population exhibited a high frequency of variation in comparison to other populations regarding its pattern of origin and relationship to landmarks such as the CB, GCHB and HN. These findings may provide further insight into the understanding of the vascular anatomy to the radiologist and the surgeon to avert complications and improve overall treatment outcome.

Intramuscular Nerves of the Inferior Rectus Muscle: Distribution and Characteristics

ABSTRACT Purpose Knowledge of the distribution of intramuscular nerves of the extraocular muscles is crucial for understanding their function. The purpose of this study was to elucidate the intramuscular distribution of the oculomotor nerve within the inferior rectus muscle (IRM) using Sihler’s staining. Method Ninety-three IRM from 50 formalin-embalmed cadavers were investigated. The IRM including its branches of the oculomotor nerve was finely dissected from its origin to the point where it inserted into the sclera. The intramuscular nerve course was investigated after performing Sihler’s whole-mount nerve staining technique that stains the nerves while rendering other soft tissues either translucent or transparent. Results The oculomotor nerve enters the IRM around the distal one-fourth of the muscle and then divides into multiple smaller branches. The intramuscular nerve course finishes around the distal three-fifth of the IRM in gross observations. The types of branching patterns of the IRM could be divided into two subcategories based on whether or not topographic segregation was present: (1) no significant compartmental segregation (55.9% of cases) and (2) a several-zone pattern with possible segregation (44.1% of cases). Possible compartmentalization was less clear for the IRM, which contained overlapping mixed branches between different trunks. Conclusion Sihler’s staining is a useful technique for visualizing the gross nerve distribution of the IRM. The new information about the nerve distribution and morphological features provided by this study will improve the understanding of the biomechanics of the IRM, and could be useful for strabismus surgery.

Genetic Analysis of the Organization, Development, and Plasticity of Corneal Innervation in Mice.

The cornea has the densest sensory innervation of the body, originating primarily from neurons in the trigeminal ganglion. The basic principles of cornea nerve patterning have been established many years ago using classic neuroanatomical methods, such as immunocytochemistry and electrophysiology. Our understanding of the morphology and distribution of the sensory nerves in the skin has considerably progressed over the past few years through the generation and analysis of a variety of genetically modified mouse lines. Surprisingly, these lines were not used to study corneal axons. Here, we have screened a collection of transgenic and knockin mice (of both sexes) to select lines allowing the visualization and genetic manipulation of corneal nerves. We identified multiple lines, including some in which different types of corneal axons can be simultaneously observed with fluorescent proteins expressed in a combinatorial manner. We also provide the first description of the morphology and arborization of single corneal axons and identify three main types of branching pattern. We applied this genetic strategy to the analysis of corneal nerve development and plasticity. We provide direct evidence for a progressive reduction of the density of corneal innervation during aging. We also show that the semaphorin receptor neuropilin-1 acts cell-autonomously to control the development of corneal axons and that early axon guidance defects have long-term consequences on corneal innervation.SIGNIFICANCE STATEMENT We have screened a collection of transgenic and knockin mice and identify lines allowing the visualization and genetic manipulation of corneal nerves. We provide the first description of the arborization pattern of single corneal axons. We also present applications of this genetic strategy to the analysis of corneal nerve development and remodeling during aging.

Facial nerve branching pattern as seen in parotidectomy in Kashmiri population: our experience

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; A prospective study to analyze the facial nerve branching pattern as seen in various parotidectomy surgeries in Kashmiri population. Main objective was to find out various branching patterns among peripheral branches of facial nerve in parotid tissue so that new young ENT surgeons could get benefited and it should be easy for them to perform parotid surgeries with less complications and unpredictable outcome.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; The prospective study was conducted in 35 patients undergoing superficial parotidectomy in our department of otorhinolaryngology GMC Srinagar over a period of one and half year. Facial nerve branching pattern was classified according to the description given by Davis et al. Branching pattern of main trunk was also observed in all cases. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The most common type of branching pattern of facial nerve in our study was type I seen in 12 (34.2%) patients, followed by type III seen in 9 (25.7%), followed by type II in 5 (14.2%), type IV in 4 (11.4%) patients, followed by type V in 3 (8.5%) and VI in 2 (5.7%).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Type I branching pattern is the most common branching pattern of the facial nerve (34.2%) followed by type III (25.7%), following the pattern as described by Davis. Main trunk was found single in 32 (91.4%%) patients however in 3 (8.57%) patients trunk was dividing in 2 branches before dividing in peripheral branching pattern as described above. &lt;/p&gt;

Effect of Prandtl number on the linear stability of compressible Couette flow

Accurate prediction of laminar to turbulent transition in high-speed flows is a challenging task. Compressibility, and the resultant large variations in the transport properties can affect the transition process significantly. In this paper, we study the influence of Prandtl number, the ratio of momentum to heat diffusivity, in Couette flows at high Mach numbers. It is a part of an ongoing research programme to isolate and understand the transport property effects on the stability of high-speed flows. As a first step, we neglect the high-temperature effects and vary the Prandtl number in the range 0.9 to 0.2, by changing the relative magnitudes of viscosity and conductivity. A temporal linear stability analysis shows that the variation of phase speed with Prandtl number leads to synchronization between two acoustic modes, with peaks in growth rate at the synchronization points. Two types of branching patterns are observed depending on the Prandtl number, and the branch type determines which of the two modes is destabilized and which one is stabilized due to synchronization. Further, the mode shapes are either retained as earlier or interchanged between the two acoustic modes depending on the branching pattern. The stability diagrams for varying Mach and Reynolds numbers show a destabilizing role of decreasing the Prandtl number, both in terms of increased disturbance growth rates, and of larger regions of instability in the parameter space. It also results in a significant reduction in the critical Reynolds number of the flow, especially at high Mach numbers with wall cooling.

Coronary artery anomaly: Rare and anomalous branching of left coronary artery

Coronary artery anomalies are rare, but still rarer is anomalous branching pattern of the left coronary artery (LCA) alone, without any congenital anomalies. We report the case of a 50-year-old man who presented with dyspnea on exertion New York Heart Association (NYHA) class II, had a positive stress test, and his coronaryangiogram revealed the left main coronary artery (LMCA) dividing into four branches. This type of branching pattern is quite rare. He had type I dual left anterior descending (LAD) artery in addition to a fairly large ramus intermedius (RI) and a nondominant left circumflex (LCx) arising from the LCA. Awareness and recognition of dual LAD is of importance to surgeons and interventionalists alike in planning the revascularization strategy.

Angiographic evaluation of branching pattern and anatomy of the aortic arch

The study aimed to investigate anatomical variations in branching pattern and anatomy of the aortic arch, and the prevalence of each type. Between September 2011 and November 2013, angiographic studies of 270 patients (144 male, 126 female) were analyzed retrospectively for variations in branching pattern and anatomy of the aortic arch. Patient mean age was 59.8 years (range, 13-88). Branching variations were found and divided into subtypes. Patients were also classified according to arch anatomy. Incidence of variations and types of aortic arch were statistically analysed. Analysis of the 270 patients revealed six types of branching pattern. Type I, classical pattern arch with three branches (TB, LCC, LS), was observed in 198 cases (73.3%). Type II (bovine arch), the most commonly observed variation, in which LCC originates from TB, was observed in 58 cases (21.5%). Type III, in which the left vertebral artery arises from the arch, was seen in seven cases (2.6%). Type IV, a combination of types II and III, was observed in three cases (1.1%). Type V, common origin of common carotids, LS and aberrant RS, was found in three cases (1.1%). Type VI (avian type), arch with only two branches, was observed in one case (0.4%). When patients were classified according to aortic arch anatomy, Type 1, Type 2 and Type 3 were observed in 195, 40 and 35 patients respectively. Knowledge of the variations and anatomy of the aortic arch is essential during interventional procedures and neck-thorax surgery.

A Failsafe Method to Avoid Injury to the Great Auricular Nerve

The great auricular nerve (GAN) is the most commonly injured nerve during facelift surgery. Although rare, injury can result in long-term sequelae. Previous reports have described the nerve's location at the midbelly of the sternocleidomastoid muscle (SCM) or at its emergence from underneath the SCM. The purpose of our study was to identify the superior course of the great auricular nerve as it applies to facelift. Thirteen fresh cadavers were dissected. A vertical line through the midlobule was drawn perpendicular to the Frankfort's horizontal, acting as a reference to the course of the GAN. Transparent paper overlay tracings were then done to record each nerve's location. The distance from the bony external auditory canal (EAC) to the nerve was measured at the anterior muscle border, at the midbelly of the SCM, and as the nerve emerged from under the SCM. Branching patterns of the nerve and its relation to the external jugular vein were identified. In 100% of the dissections, the superior course of the GAN fell within a 30-degree angle constructed using the vertical limb perpendicular to the Frankfurt horizontal and a second limb drawn posteriorly from the midlobule. The distance from the EAC to the nerve was 4.9 ± 1.1 cm at the anterior muscle border, 7.3 ± 1.0 cm at the midbelly of the SCM, and 9.8 ± 1.2 cm at the GAN's emergence from under the SCM. Four types of branching patterns were identified. The 30-degree angle described above rapidly and accurately identifies the nerve's location.

Various types of branching patterns of celiac trunk

According to conventional anatomy, the celiac trunk divides into left gastric artery, common hepatic artery and splenic artery. The variations of branching patterns of celiac trunk may create surgical complications. Therefore the study has been carried out to identify and evaluate the spectrum of normal and variant anatomy of celiac axis by spiral computed tomography in the Departments of Anatomy and Radio‐diagnosis, C.S.M. Medical University, U.P., Lucknow, India. CT‐angiograms of 50 subjects were analyzed. In the present study, the celiac artery displayed classical trifurcation (28%), bifurcation (8%), quadrifurcation (36%), pentafurcation (20%) and hexafurcation (4%). Celiac trunk was absent in 4% cases. Knowledge of such variations can revolutionise successful surgical procedures around celiac trunk and the planning of image‐guided interventions.No financial support is obtained from any source.

USE OF MR CHOLANGIOGRAPHY IN LIVING-RELATED LIVER DONORS — COMPARISON WITH INTRAOPERATIVE CHOLANGIOGRAPHY

Magnetic resonance (MR) imaging plays an important role in the preoperative evaluation of the living-related liver donors to reduce postoperative morbidity and complications. Though invasive, intraoperative cholangiography is still the golden standard in demonstrating anatomical variation of bile ducts. We design this study to compare the validity and reliability between these two imaging modalities and retrospectively searched the database of living-related liver transplantation (LRLT) center during the period from April 2005 to September 2008. The clinical information and images of total 58 donors (female : male = 35 : 23) were reviewed. Five types of branching patterns of the bile ducts were encountered. The rate of disagreement in the classification of branching pattern between MR and intraoperative cholangiography was 5% (3/58). Intraoperative cholangiography could detect significantly more division degree of right hepatic ducts (mean degree: 7) than MR cholangiography (mean degree: 4) (using paired t-test, p &lt; 0.05). No significant difference existed in the detection of division degree of left hepatic ducts. However, MR cholangiography was significantly better than intraoperative cholangiography in demonstrating major branches of the left hepatic ducts including tributaries of segment 2 and 3 (58/58 versus 35/58) (using McNemar's chi-square test, p &lt; 0.05). We conclude that MR cholangiography is nearly as good as intraoperative cholangiography in identifying the branching pattern of bile ducts, and demonstrates the major left hepatic ducts better.

Diversity of panicle branching patterns in wild relatives of rice

Panicle branchiness is one of the key characters specifying rice yield. To understand the potential of panicle branchiness, the diversity of panicle branching patterns was investigated in 43 accessions of 19 wild Oryza species and 27 accessions of O. rufipogon, which is the wild ancestor of the Asian cultivated species O. sativa. All these accessions were selected from a core collection of wild relatives of rice maintained at the National Institute of Genetics (NIG), Mishima, Japan. We found that panicles of wild Oryza species closely related to O. sativa generated primary branches with homogeneously large numbers of secondary branching organs, resulting in a truncated conical type of branching pattern. In contrast, panicles of distantly related wild species had primary branches with acropetally declining numbers of secondary organs toward the distal end of panicles, resulting in a conical type of branching pattern. The main axis meristem, which was aborted in closely related species, was converted into a terminal spikelet in distantly related species. Our data suggested that the panicle branching pattern evolved from conical to truncated conical in the genus Oryza. The possible advantage of a truncated-conical type of branching pattern for rice yield will be discussed.

Anatomy of branches of the musculocutaneous nerve to the biceps and brachialis in human fetuses

Forty upper limbs (20 right and 20 left) of spontaneously aborted human fetuses were examined to determine the branching patterns of the musculocutaneous nerve. The mean age of the fetuses was 21.3 weeks. We identified three branching patterns of the musculocutaneous nerve to the biceps muscle. Type I with a single primary branch occurred in 47.5% of cases. Type II with two primary branches each to a separate head of the biceps muscle was observed in 42.5% of cases. Type III consisted of two primary branches, the proximal dividing into two branches, each to a different head of the biceps, and the distal branch supplying the common belly. Type III was present in 10% of cases. We found only one branching pattern for the brachialis muscle, a single primary branch. In our material communicating branches between the median and musculocutaneous nerves were found in 20% of specimens. We measured the distances between the acromion and the exit points of the first and second branch to the biceps, which averaged 36.3% for the first branch regardless of the type of branching pattern, 54.2% for the second branch in Type II, 60.7% for the second branch in Type III and 60.9% for the branch to brachialis, expressed as a percentage of the distance between the acromion and the lateral epicondyle.

Separated components of root exudate and cytosol stimulate different morphologically identifiable types of branching responses by arbuscular mycorrhizal fungi

Two morphologically distinct hyphal branching responses by the AM fungus, Glomus intraradices, were stimulated by separated components of carrot root exudate. Complex branching up to the sixth order was induced by compounds most soluble in 35 % methanol, whereas the formation of more lateral branches (second order) was stimulated by compounds most soluble in 70 % methanol. This same 70 % alcohol soluble fraction also stimulated a completely different type of branching pattern in another fungus, Gigaspora gigantea. This pattern consisted of a very periodic distribution of dense clusters of hyphal branches that had a very high degree of complexity. In contrast to exudate components, separated cytosolic components of carrot roots did not stimulate any of the observed hyphal branching patterns. Alcohol-soluble fractions actually inhibited hyphal tip growth of G. gigantea and induced the formation of “recovery” branches that were identical to those induced by an inhibitor found in the exudate of Chard ( Beta vulgaris ssp. cicla), a non-host plant.